Massive Science - Marnie Willman Newly published articles from Marnie on Massive Science en-US daily 1 Tue, 14 Sep 2021 08:55:00 EST Your saliva affects the way you spread pathogens Our saliva can vary depending on our physiological state, making us more or less likely to pass on bugs to others ittle baby with saliva on his lips ittle baby with saliva on his lips We've all been in a crowded place and seen someone sneezing or coughing nearby. You do your best to get away from them, but somehow they always end up right there beside you. The COVID-19 pandemic has increased our collective use of masks and other protective measures that have reduced the transmission of many viruses beyond coronaviruses, including influenza. 




]]> Thu, 29 Apr 2021 22:02:44 EST Researchers create an effective RNA vaccine for malaria Tech similar to COVID-19 mRNA vaccines might prevent one of the world's deadliest diseases An Anopheles stephensi mosquito is obtaining a blood meal from a human host through its pointed proboscis. Note the droplet of blood being expelled from the abdomen after having engorged itself on its host’s blood. This mosquito is a known malarial vector with a distribution that ranges from Egypt all the way to China. An Anopheles stephensi mosquito is obtaining a blood meal from a human host through its pointed proboscis. Note the droplet of blood being expelled from the abdomen after having engorged itself on its host’s blood. This mosquito is a known malarial vector with a distribution that ranges from Egypt all the way to China. Marnie Willman Malaria remains a significant problem facing Africa. Of the 409,000 worldwide malaria deaths estimated by the WHO in 2019, 94 percent of all cases occurred in Africa. 

Malaria is caused by a parasite, carried and transmitted to humans by female Anopheles mosquitoes (there are more than 400 species of this particular type of mosquito, and 30 of them can carry malaria). The battle between malaria and science remains because of a handy trick this parasite plays on the immune system. 

Our immune system has a component called "MIF" which stands for "cytokine macrophage migration inhibitory factor." The job of MIF is to regulate the movement of immune cells to the site of an infection (either attracting them to the site, or stopping them from continuing to arrive once the invader or injury is gone). Plasmodium, the one-celled parasite that causes malaria, can produce a nonfunctional "decoy" of MIF, causing our confused immune system to then fail to make the T cells that would normally be stimulated as a result of regular MIF activity during infection. The ultimate result is no production of T cells, which would normally make memory B cells that would generate long-lasting immunity against the malaria. 

Now you might be able to see why designing a vaccine is challenging for malaria. In a typical vaccine, a bit of protein or a deactivated virus or bacteria is used to stimulate the immune system. Your immune system then pumps out antibodies against that invader, and you're left with memory B cells that remember that infection; the body is then primed and ready to fight a future infection. The Plasmodium parasite interferes with the process of T cells leading to those long-lived memory B cells that would fight off future infections faster and more efficiently. So, your next encounter with this parasite would be the same as your first, with no built-up immunity from previous infections. 

Red blood cells infected with Plasmodium falciparum, the parasite that causes malaria in humans. During its development, the parasite forms protrusions called 'knobs' on the surface of its host red blood cell which enable it to avoid destruction and cause inflammation.


National Institutes of Health via Wikimedia Commons

Thankfully, there is hope. Yale researchers recently filed a patent for a malaria vaccine using a RNA platform. mRNA vaccines are a relatively new technology that uses non-infectious and non-integrating (this means it won't accidentally become part of your healthy cells) piece of genetic material from the pathogen of interest (in our case, malaria). 

mRNA is kind of like instructions for generating a protein. By delivering the mRNA as a vaccine, your body takes the genetic material up into cellular cytoplasm (the liquid inside of your cells), and begin to make the protein by following instructions within the mRNA. This new protein is then released, spotted by your vigilant immune system, and flagged. As your body becomes aware of the threat, your T cells and immune system are activated, and memory B cells are formed against the pathogen. Just like that — you're immune! 

While there is a vaccine currently available for malaria, it isn't very effective. For now, mosquito nets remain the best (and often only) preventative measure against this deadly disease.


Ivanna Mykhailiuk on Upsplash

This new vaccine, generated by Richard Bucala and Andrew Geall is an saRNA (similar to mRNA, but more efficient) vaccine that encodes the PMIF that Plasmodium normally uses to disarm our immune system. As Bucala and Geall discovered, immunizing patients with saRNA that encodes PMIF uses the parasite's own gene against it, and confers protection. These results were also seen in a study from 2018, in which MIF was tested successfully used as a treatment for malaria infection in a mouse model. 

Malaria and COVID-19 have two thin in common. Both are serious problems continuing to cause high caseloads and fatality rates globally. Both have had mRNA-based vaccines suggested as their solution (malaria is an experimental vaccine, COVID-19 mRNA vaccines have now been approved and are in use). Researchers continue to test mRNA vaccine candidates for a variety of diseases in the hopes that more solutions to deadly pathogens will be found. 

A newspaper article with the headline "mass vaccinations begin"

A newspaper article with the headline "mass vaccinations begin"

Little Plant on Unsplash

Bucala and Geall's new malaria vaccine candidate is a great example of a new technology being applied to a previously unsolvable problem. This is what science is all about. mRNA vaccines have been applied to a number of problematic pathogens including COVID-19, rabies, Zika virus. Perhaps the most famous mRNA vaccines are the ones developed in the last year to target the SARS-CoV-2 virus that causes COVID-19. The Pfizer Inc and BioNTech vaccine (almost 94 million doses have been administered in the US alone in recent months) is an mRNA vaccine, as is the Moderna vaccine, which is ramping up production and distribution. Researchers and doctors alike continue to hope that this technology will help us see the end of the most significant global outbreak in recent history. 

]]> Sat, 29 Aug 2020 09:26:00 EST Hepatitis C virus tracking could be made easier by next generation sequencing The information from sequencing would help epidemiologists trace the disease A person performing a genome sequencing to compare the genetic sequences of viruses A person performing a genome sequencing to compare the genetic sequences of viruses. An estimated 50,300 people in the United States are newly diagnosed with Hepatitis C each year. With approximately 2.4 million people in the US already living with the virus, this presents a large healthcare burden to the global medical economy. Within this group, there is a proportion of people so often forgotten in the shuffle: injection drug users. 

Researchers, doctors, and scientists have been working to eradicate Hepatitis C for decades, but one of the biggest barriers faced is injection drug use. Sharing of needles and other supplies frequently transfers bodily fluids between people, which is how Hepatitis C virus is transmitted. And, just 7.7% of people who inject drugs are tested for Hepatitis C. This, among other challenges, such as the fact that people who inject drugs may face stigma and judgement when they seek out health care, makes tracking Hepatitis C difficult.   

A recent study examined the feasibility of using a method called next-generation sequencing to determine similarity of Hepatitis C virus strains between individuals. They found this is a feasible option that could provide epidemiologists with information such as how different strains in populations of people are related and where one newly infected person's strain of the virus may have originated. 

While this doesn't completely solve the problem of track-treat-eradicate, it does help with the tracking portion, which has been severely lacking. Testing for the disease tends to take a few days at minimum, and may require follow-up testing. Each step brings us closer to being able to treat and eradicate the disease, eliminating Hepatitis C virus from the globe, preventing the 8,000-10,000 deaths each year that it causes. 

]]> Sat, 15 Aug 2020 08:33:00 EST New research on Nipah virus finds the virus spreads rapidly as patients approach death This science must be balanced with the rights of sick people and their loved ones cemetery a cemetery with a large tree in the middle If you followed the news during the Ebola Virus outbreak in the Democratic Republic of the Congo, you might remember reading that the funeral practices in the region were not compatible with outbreak control measures. Traditional funeral practices in Africa include washing and touching the body extensively after someone dies to prepare them for burial. This poses a problem because many viruses, including Ebola, are passed through bodily fluids such as sweat and blood and remain contagious after the infected person has died. 


Recently, scientists have turned to Nipah virus (an infectious respiratory illness) transmission in Bangladesh to understand disease transmission dynamics. Contact patterns, or contact tracing, is used to track how viruses spread from one person to another. Whether, like COVID-19, the virus is spread by respiratory droplets, or like Nipah or Ebola by bodily fluids, contact patterns show how the virus spread by examining the chain of infection. This aids epidemiologists in tracking how viruses move through populations, and can improve future outbreak preparedness. 

They found that, similar to Ebola, the number of personal contacts between a sick person and their friends and family increases rapidly as they person approach death. This is because family and friends want to visit the person, fearing it is their last chance to see them, and people begin to arrive for funeral preparations. The sickest (and likely most contagious) people had more contacts, leading the researchers to conclude that end-of-life preparations spread the virus rapidly. 

This suggests that disease control efforts should focus on funeral practices, an approach we have also seen during the current pandemic, with friends and family mourning their loved ones over Zoom. However, this is an instance where scientific best practices intersect with important human rights and ethics considerations — for example, in 2014 the WHO released a "safe and dignified burial" protocol to ensure that deceased Ebola patients, their families, and their cultural practices are treated respectfully.

]]> Fri, 31 Jul 2020 11:37:00 EST Wolbachia bacteria stop mosquitos from spreading viruses You may have never heard of Wolbachia, but these bacteria could save us from dengue and malaria wolbachia bacteria micrograph of the wolbachia bacterium The Aedes aegypti mosquito is one of the most notorious insects because of it can transmit tropical diseases such as dengue, yellow fever, malaria, and Zika virus. Climate change threatens to amplify their damage as increasing global temperatures enable the mosquitoes to survive in new geographical areas that were traditionally too cold. 





]]> Mon, 13 Jul 2020 17:25:00 EST Eating more fiber feeds whipworm parasites in our guts New research shows that interactions between diet and parasites might make people with whipworm infection sicker whipworm parasite microscope photo of an oblong parasite Has your doctor ever advised you to increase your fiber intake to improve your overall health? Well, if you've got a parasite, it turns out that is terrible advice! Researchers at University of Copenhagen have discovered that parasitic gut worms (in particular, Trichuris muris, a whipworm) survive and reproduce easier in mouse gut tracts that have higher levels of fermentable dietary fiber. 



Tiia Monto [CC BY-SA 3.0]




]]> Thu, 09 Jul 2020 22:44:48 EST The sugar in semen makes HIV drugs less effective High levels of the sugar can obstruct antivirals from linking with viruses Scanning electromicrograph of an HIV-infected T cell Scanning electromicrograph of an HIV-infected T cell Marnie Willman Well over half a million people die of HIV/AIDS each year, making it one of the leading causes of death in the world. According to data from 2019, 38 million people around the world live with HIV/AIDS. 

The good news is that in 1990, researchers found the first effective treatment for HIV/AIDS, called antiretroviral therapy. The therapy represents a cocktail of antiretroviral drugs, each designed to limit viral replication and infection. By the end of 2019, an estimated 25.4 million people accessed antiretroviral treatment for HIV/AIDS — about two-thirds of those infected — preventing a large portion of the deaths that this sexually transmitted infection previously caused. That said, antiretrovirals have to be taken every day, and resistance and progression from HIV to the historically untreatable AIDS can occur. 

HIV and AIDS antiretroviral therapy

HIV/AIDS antiretroviral therapy


Researchers at the University of Iowa have now found that semen, which is the primary mode of transportation of HIV between humans, can affect how well antivirals — including those used in antiretroviral therapy — work against the virus.

Semen contains fructose, the primary energy source that spermatozoa, or sperm, need to swim and survive. If sperm didn't have the energy they get from fructose, it would be like a runner trying to complete a marathon without eating anything prior to the event. For that reason, fructose in semen has long been the target of infertility studies, but could it have an effect on HIV transmission beyond simply slowing sperm?

According to the study published recently in the Journal of Virology, fructose can reduce HIV's ability to bind to 2G12, a human antibody that typically targets viruses like HIV for destruction. Instead of neutralizing HIV, the 2G12 antibody produced by a person's immune system is temporarily "clogged" with fructose, which sticks extremely well to the antibody. This means that, when semen is introduced to HIV, the two work together to prevent antibody functioning. This leaves the HIV free to go on infecting other healthy cells, free from immune detection. However, the effect of fructose is likely not permanent, as the fructose-laden semen becomes scarce as the HIV moves beyond the reproductive tract. This temporary partnership makes it easier for the HIV virus to get into the body without being immediately tagged for destruction by the 2G12 antibody, but is by no means a permanent key to freedom. 

An example of antibody (green) targeting a critical area (yellow) of a viral protein (red, in this case HIV).


National Institute of Allergy and Infectious Diseases, National Institutes of Health

They also investigated an HIV treatment called Griffithsin which is a protein that comes from algae. Griffithsin normally works by binding to molecules on the surface of the virus, and linking them all together in a complex matrix, so the HIV cannot bind to anything else. This ties up the surface with Griffithsin, restricting any ability of HIV to infect healthy cells. In a cellular model, they examined the effect of adding fructose to Griffithsin plus HIV, and found that fructose reduced the treatment's ability to bind with HIV. This suggested that fructose was interacting with Griffithsin the same way the surface molecules of HIV would, rendering it "full" and unable to bind to HIV. These findings suggest that fructose in semen may be able to inhibit attachment of HIV to target cells, but the authors say more investigation is needed to know that for certain.

The investigators chose to adopt a different cell model approach than most human semen studies which use human clinical samples for their work. They prepared a synthetic formulation which they called "simulant seminal plasma" (sSP) instead of human samples. This avoids the problem of attaining ethics approval for work with human samples, and the complications of differences between individual sperm samples — making it easier to replicate studies. The sSP formulation is made of many of major constituents of semen all at the right pH, and mimics human samples. The importance of this lies in repeatability of future work, and it's wide-reaching applications to future STI, infertility, and cancer studies. Imagine being able to further investigate these problems and potential treatments by using a formulation that is standardized and accurately mimics human semen. It would be a major step forward in the research world. 

Finding that fructose in human semen seems to make antivirals we use against HIV much less effective has important implications for antiretroviral therapy, used by millions of people. If the fructose naturally occurring in semen could render these less effective, scientists may need to reformulate these drugs. It may also be important to test future novel antivirals against HIV in the presence of elevated fructose, to ensure the fructose does not render them ineffective. Finally, the synthetic semen formulation outlined by this research introduces a novel approach to STI/infertility/cell culture research involving human semen. Together, this story packs one heck of a punch into the HIV research world, and provides hope for improvement of future studies and the treatments they may result in. 

]]> Thu, 02 Jul 2020 10:34:48 EST Researchers develop a better test for the parasite that causes river blindness The WHO estimates that 205 million people in African countries are at risk of infection onchocerca parasite a microscope slide of a nematode parasite A parasite prominent in sub-saharan African rivers called Onchocerca volvulus (pictured above) is one of the 17 neglected tropical diseases selected by WHO in 2003 for directed control or elimination. Transmitted by bites of Simulium blackflies that breed in rivers, the parasite causes 'river blindness'. Approximately 500,000 people are visually impaired by the disease, and many more have other symptoms of the disease. The WHO estimates that 205 million people in sub-Saharan Africa are at risk of infection. 




]]> Tue, 02 Jun 2020 09:42:00 EST Cytokines prevent the whooping cough bacteria from invading the rest of the body (in mice) Researchers hope that this finding will eventually lead to new treatment for the disease in infants cute baby a baby underneath a blanket looking at the camera Whooping cough, caused by Bordetella pertussis bacteria, causes 24.1 million cases and 160,700 deaths each year, according to the CDC. This is probably an underestimate, as many people don't report or aren't hospitalized for their illness, and thus are not counted in the total. Scientists are still trying to piece together the immune response we mount to the illness, particularly why whooping cough is most deadly in babies and toddlers.

Researchers from University of Maryland School of Medicine believe they have found part of the answer, and it lies in the differences in immune response between young children and adults. In this study, the researchers used lab mice infected with B. pertussis to mimic human infections, and studied the immune response following infection in infant and adult mice. 

Type I and III interferons are cytokines, substances that are secreted by immune cells to signal that an infection is occurring. The elevated levels of Type I and III interferon seen in adult mice post-infection were not present in the infant mice in the study. The adult mice showed a delayed but significant increase in their interferon levels in the lungs, which stopped the bacterial infection from spreading throughout the body. 

The infant mice had no interferon response, and as a result the B. pertussis bacteria were free invade the rest of the body. They eventually killed the young mice by stimulating an overwhelming, body-wide infection. 

Could boosting interferon levels in babies and children improve their survival, and reduce mortality from this devastating disease? This, excitingly, opens a new door for pediatric whooping cough treatments.  

]]> Mon, 11 May 2020 17:17:40 EST West Nile Virus-carrying mosquitos managed to survive a German winter Europe is usually too cold for tropical diseases to persist for long, but climate change helped it overwinter The house mosquito, Culex Pipiens, a common carrier of West Nile Virus The summer of 2018 in Germany was the second hottest and driest year on record, and while this made for a beautiful season of beach-side fun, it also brought a deadly disease with it. The West Nile Virus (WNV) outbreak of 2018 was a single-introduction event, thought to be from the Czech Republic. The infection was detected in wild and aviary birds such as owls and blackbirds, in addition to horses. This was the first documented occurrence of WNV in these birds in Germany. When the outbreak was declared over, a sigh of relief was felt across the country. But the problem was far from over. 





]]> Thu, 07 May 2020 11:10:54 EST Parasitic wasps murder insects with a smallpox-like virus ...and other words everyone is happy to hear Scared people scared people In the virus world, smallpox and other poxviruses are horrifying. Despite the fact that smallpox was successfully eradicated in the 1970s, the entire family of poxviruses still strike fear into the heart of scientists.


parasitic wasp

Parasitic wasp attacking an aphid

Wikimedia Commons




]]> Sun, 19 Apr 2020 09:35:00 EST Can hormone levels signal for autism in girls? New study moves against the current of gender bias in autism research puzzle penguin girl puzzle penguin girl Since the 1940's, when the word "autism" was introduced in the US, diagnoses and treatments have skyrocketed in prevalence and normalcy. In fact, the United States now estimates 1 in 54 American children have some form of Autism or Autism Spectrum Disorder (ASD). Despite the surge, the differences between people diagnosed makes pinpointing a specific cause nearly impossible. 

However, one thing all experts agree on is the fact that autism seems to occur more often in boys than in girls. While many girls with autism may be overlooked due to sex or gender biases, studies have found the prevalence in boys to be four times higher

Studies have looked at sex hormones, male-specific genes, and male vs. female brains to resolve this difference. And some have turned up answers. However, this disparity in research favoring boys neglects the girls with autism, whose struggles and needs are no less important, regardless of the fact that they are fewer in numbers.

A recent study from the University of Bern decided to instead tackle the question of cause with these girls in mind. The study analyzed certain hormones, particularly androgens such as testosterone, and their levels in teenage girls with autism. 

They found that these girls had higher levels of both testosterone and androstenediol. But, they also found that those levels weren’t elevated in their urine. Plus, they had the same or lower levels of enzymes used to process those hormones. 

This seems to implicate the brain’s hormone control center – the hypothalamus – in the cause. Their bodies seemed to be unaware of their elevated androgen levels, since they aren’t getting rid of them in urine or processing them with extra enzymes. 

Finally, this study also suggests that changes in the levels of androgen hormones may be used as a diagnostic marker for autism. Such a diagnostic tool is an important step forward, as autism diagnosis currently based on behavior, movements, and development in early years, all of which differ significantly between children with and without autism. 

]]> Tue, 14 Apr 2020 16:29:18 EST We could soon be harvesting anti-viral antibodies from tobacco plants "Plantibodies" represent a new avenue for treatments against fast moving viruses like influenza or coronavirus A tobacco plant genetically engineered with a firefly gene to glow bright green. Marnie Willman With infectious disease outbreaks such as COVID-19 remaining a continual threat, and cancer rates on the rise, we rely on modern medical treatments like antibodies more than ever before. Antibody production is a major source of research animal use. Scientists use what are called "humanized mice," which are mice that have immune machinery to make human antibodies, to create antibodies to human medical treatments. Antibodies function by tagging "foreign bodies" like cancer cells, bacteria, viruses, or anything that isn't human, marking them for destruction by the immune system.

Antibodies produced by mice are used for treating a wide variety of conditions, including cancer, Crohn's Disease, asthma, septicemia, and viral infections. However, obtaining these life-saving antibodies from the blood of mice is expensive, not to mention lethal for the animals themselves.

"Plantibodies" offer a new solution to this problem. These are antibodies made from plants that have been genetically engineered to express human antibodies. They've been in use, under the radar, for a while. Perhaps the most notable plantibody cocktail is the ZMapp Ebola vaccine that was used to try and stem the outbreak in the Dominican Republic of the Congo (though ultimately found to be less effective than other therapies).

A microscope image of H1N1 influenza virus particles, colored purple.

A microscope image of H1N1 influenza virus particles, the virus tested in the guinea pig study.

Centers for Disease Control

Jun-Gyu Park and colleagues from University of Rochester Medical Center recently showed that human antibodies produced in tobacco plants can lower influenza infection rates in guinea pigs. When sick guinea pigs were treated with plantibodies and housed with healthy guinea pigs, they were less likely to transmit the virus to their unprotected cage-mates. The researchers concluded that these particular plantibodies have the ability to protect the animals from catching and transmitting influenza, even when they only took the plantibodies 6 hours before infection (compared to influenza vaccination, which requires 2 weeks or more to become effective).

The same researchers previously isolated an antibody that effectively killed the influenza virus in several cell and animal models. Building on this exciting finding, this research ported the same antibody to be produced in tobacco plants instead in a lab. Given the antibody worked as well against influenza virus in guinea pigs when produced in tobacco plants compared to cell culture methods, this provides an alternative with a much lower manufacturing cost.

There are concerns about plantibodies being allergenic in animals and humans. Because of the slightly different ways that plants produce proteins in comparison to animals, plantibodies may be recognized by a patient's body as being foreign, triggering an allergy-like immune response. In addition, plantibodies cannot be produced in all plants, further limiting options for production. 

Crop researchers produce plantibodies by genetically altering corn, alfalfa, tobacco, and a variety of other crops. However, scientists and politicians agreed it would be safest to reduce contamination potential by restricting plantibody production and research to "non-consumptive crops." This would ensure food crops wouldn't be accidentally contaminated with antibody-producing genes.

While it rarely makes headlines, seasonal influenza continues to cause 12,000-61,000 deaths and millions of cases of illness each year. The current influenza vaccine is great, but it comes with a number of problems, like the low number of people who get the vaccine each year, and the ever-changing nature of seasonal influenza varieties circulating. With ever-growing resistance to antivirals, influenza remains a great threat for a future pandemic.

Plantibodies could be an alternative to vaccination, which is often skipped entirely because it's seen as being unnecessary or ineffective, and antivirals, which are resulting in resistance. Plantibody-based vaccines are more stable at a greater range of temperatures compared to standard vaccines, which must be kept at a specific temperature and have a short life. Another fear regarding influenza vaccination is how vaccines are made: using a lot of eggs. This is a problem for those allergic to eggs, and for avian influenza, which can wipe out egg supplies, creating a shortage for vaccine creation come flu season. A plantibody treatment does not face these same crises, and tobacco plants are extremely hearty, non-consumptive crops, making them an ideal plantibody source.


An example of an antibody (green) targeting a critical area (yellow) of a viral protein (red, in this case from HIV).

National Institute of Allergy and Infectious Diseases, National Institutes of Health

The finding that guinea pigs not only transmit viruses less efficiently to their cage-mates, but also become less sickened shows another benefit to using plantibodies. Vaccines are intended to prevent us from getting diseases by giving our immune system a chance to build immunity against a dead or pseudo-virus before we come in contact with the real virus. However, being vaccinated against influenza doesn't necessarily mean you won't catch the flu. Mismatches between the vaccine strain and the strain circulating during that particular season, lack of herd immunity from low vaccination, and a host of other problems can still lead to infection. However, if anti-flu plantibodies can make people less infectious if they do become infected, that can limit viral spread on its own.

Plantibody research is of great interest to the medical system, animal ethics groups, and the economy. For ethical reasons, they are better than using mice, ferrets, rabbits, or other animals that traditionally have been used for antibody production. They are also more inexpensive than traditional antibody production because of the limited processing required compared to harvesting antibodies from animals like mice. They can be scaled up and produced in high quantities for clinical use, as was done for the ZMapp Vaccine, making their use a feasible medical treatment.

Plantibodies have the potential to increase accessibility to medical treatments for a variety of ailments which previously required expensive or difficult-to-transport medications for example, vaccines often have to be kept at a low temperature during transport, which can be difficult in hot or developing countries. From influenza to Ebola, coronavirus to cancer, this new treatment is sweeping the pharmaceutical field, even claiming a line in the $7.2 million Euros Horizon 2020 project, which was awarded to the John Innes Center to fund their research on plantibody development.

]]> Thu, 05 Mar 2020 15:50:00 EST Children that go to school near major roadways experience more severe asthma New research reiterates that air pollution is a public health risk, and that children in cities are particularly at risk school bus school bus on a main road The correlation between pollution and lung health, particularly asthma, has been suspected since the industrial revolution, when cases of lung and respiratory illness skyrocketed with the rate of air pollution. A 2020 study by a group of researchers at Harvard Medical School has now looked at the many socioeconomic factors that come with this discovery in present day cities. For example, lower income families tend to live closer to major roadways, in densely populated cities, in regions with higher pollution

The study surveyed children living with asthma in urban northeastern American schools living in inner-city areas. The homes and schools of the children studied were mapped and their proximity to major roadways measured. The likelihood that a child experienced asthma symptoms, and the frequency that they experienced them, was shockingly different between children in schools close to major highways and those further away. 

In fact, for every 100 meters further from major roadways (in terms of school location), children were 29% less likely to report asthma symptoms in general, including need of an inhaler and asthma attacks. These results show us that children attending school near major highways, which are increasingly numerous across North America, have higher asthma rates and more severe symptoms, compared to students who do not go to school near major roadways.

Pollution is hard on our lungs, particularly when an underlying condition such as asthma is present. This study implies that more attention needs to be given to children attending school in inner-city, traffic-heavy districts, including monitoring of their lung health and asthma progression. These studies are difficult to perform because so many factors, such as socioeconomics and genetics, can also influence asthma and lung health, there is rarely a clear and direct cause-and-effect relationship. But, studies like this pave the way for future findings and improvement of conditions for asthmatics in city centers around the world. 

]]> Tue, 04 Feb 2020 12:52:38 EST Bats' unique immune systems make them stealthy viral reservoirs These ecologically important animals have been at the center of many major viral outbreaks, and we are beginning to understand why fruit bat in tree a large bat hanging in a pine tree Marnie Willman In 2001, Nipah virus emerged in India, causing an estimated 66 cases and 45 deaths after people unknowingly drank contaminated raw date palm sap. In 2002, SARS (a coronavirus termed Severe Acute Respiratory Syndrome) arose in Asia, resulting in 8,000 infections and almost 800 deaths globally. And from 2014-2016, the Ebola virus outbreak shocked the world, sickening over 28,000 people and killing over 11,000 across Africa

Coronaviruses (a family of closely related respiratory viruses) have now made headlines again, in the form of 2019-nCoV, the new coronavirus that emerged in Wuhan, China. As of February 2nd, there have been 14,564 cases and 305 deaths from 2019-nCoV, with cases confirmed in 25 countries. All of these alarming outbreaks have one intriguing factor in common: bats. 

bright green virus particle under microscope

Nipah virus is one example of a bat-borne disease that can spill over into humans

NIAID on Flickr

We have known for quite some time that bats were the primary source of both the SARS epidemic and the Nipah virus. The Ebola virus also originates in fruit bats, which can infect other forest animals who then pass the virus to humans. And evidence strongly suggests that bats have played this same role – which scientists term the "reservoir species" – in the coronavirus outbreak. There are over 1,300 known species of bats, making them the second largest group of mammals on Earth. But their strange immune systems that make them the reservoir species for so many viruses are what make them truly special. 

Humans aren't constantly exercising; we jog, or work out for a bit, but then we stop. As a result, unless we are very sick, our body temperature stays around 36.4 degrees Celsius. If we do have a fever, that stimulates an inflammatory response, and our immune system quickly kicks into action, eliminating the foreign pathogen from our bodies. However, bats are constantly exercising: they fly, which increases body temperature and metabolic rate. This led scientists to come up with an initial theory as to why bats have a strange immune system, known as the "Flight as Fever" hypothesis. Because bats' bodies are often put into what, for humans, is a "fever" state, they may be more resistant to viral damage, allowing them to become symptom-less carriers of viral disease. 

In a recent review, virologist Arinjay Banjeree and colleagues summarized the immunological differences between bats and humans to uncover why these animals make such effective viral reservoirs. The first difference they noted was interferon levels. Interferons (IFNs) are an immune substance animals secrete to eliminate viruses. Humans have them, and so do bats. When grown in labs, analysis showed that bat cell lines produce higher levels of type I IFNs than human cell lines. Type I IFN is responsible for a variety of anti-viral jobs including limiting viral replication, killing infected cells, and activating other immune cells. Though wild bats have been shown to carry high IFN levels as well, the link between bat cell line behavior in the lab and bat's natural immune system needs more work.

There's more strangeness, on top of their high interferon levels and flight-induced fevers. A study on Big Brown Bats revealed that bats have lower levels of inflammatory cytokines in their blood than we do. Inflammatory cytokines are substances in our bodies that race to the site of an infection, bringing immune cells with them, which helps to quench it locally before it can spread. This allows infected bats to keep spreading diseases to other animals without becoming victims themselves.

Bats are ecologically important and fascinating animals, but we must be conscious of limiting human-bat interactions to stop the spread of diseases

 Photo by Hans Veth on Unsplash

Environmental stressors – such as drought or extreme temperatures – can increase the rate at which bats pass diseases to humans. Not only does stress in general tend to reduce animals' immune functions, but stressors such as shortages of food or water can force bats to migrate, spreading disease further. In fact, a recent "spillover" (the passing of a virus from a reservoir species into a new host) of Hendra virus from fruit bats in Australia correlated with a food shortage for local bats due to a climate shift. Because the bats were under nutritional stress, they were more infectious, which coincided with their moving into new territories in search of food. This created a perfect storm of new hosts and infectious reservoirs, resulting in an outbreak of Hendra among horses.  

Attempts to study bat immune cells in the lab haven't made much progress. Many bats do not develop the symptoms of the viral diseases they carry, and when they do, attempts to culture their cells in the lab have been unsuccessful (essentially, the cells cannot survive in a laboratory environment, and they die). In 2018, a Gammaherpesvirus was isolated from Big Brown Bats and maintained in tissue culture, representing a huge leap forward in bat-virology research. However, progress has been slow and restricted to just a few cells types from a few species of bats. 

With the great diversity in bat species, their unique immune adaptations that support asymptomatic carriage of viral diseases, and the fact that bats are in close contact with humans around the world, it is no great surprise that bat-borne diseases have followed humans throughout history. From Ebola to herpes, bats represent a reservoir for a number of devastating diseases and viral outbreaks due to these animals is likely to continue increasing. With so much left to learn and discover about these little creatures, it's no wonder they remain at the forefront of human health headlines. 

]]> Tue, 07 Jan 2020 14:16:36 EST Viruses can infect the brain, hide out for decades, and then cause Viral Parkinsonism How do you study a disease that takes decades to reveal itself? In this case, scientists used mice, viruses, and a little immunotherapy brain scan photo scientist Marnie Willman In recent years, a mysterious surge of a Parkinson's-like disorder spread around the world, causing an estimated 10-15% of the ten million worldwide Parkinson's Disease diagnoses , baffling doctors and stunning scientists. For years, no one had any idea where the disease was coming from. 

Many of these patients were survivors of viral diseases that had infected the brain and led to viral encephalitis. Viral encephalitis is brain swelling and damage, which can occur when a virus infects the central nervous system and ends up in the brain, a condition which can be disabling and often fatal. In fact, nearly every Spanish Influenza patient who had an acute episode of encephalitis (brain swelling and damage during infection) from the influenza virus went on to develop what was later termed "Viral Parkisonism". Epidemiologists have determined that Spanish Influenza survivors have a 2-3x higher risk of developing Parkinson's Disease, now termed Viral Parkinsonism, compared to those who did not come into contact with the virus. Since this time, viruses like the West Nile Virus, HIV, and Western Equine Virus have all been attributed to Viral Parkinsonism development later in life. 

Viral Parkinsonism is a disease of neural degeneration from a viral infection that causes encephalitis, or brain inflammation. The strange thing about this illness is how long the delay between infection and disease can be, throwing off a doctor's diagnosis (it's hard to diagnose a cause when it occurred decades before symptoms). There are Parkinson's-like symptoms such as loss of motor control, stiff movements, and loss of balance or difficulty walking. These symptoms arise in eerily high rates post-viral-infection, including in more than 50% of West Nile Virus survivors and nearly 25% of Western Equine Encephalitis Virus patients in a recent Colorado epidemic. But what causes this development of brain damage and its late onset remains a mystery to scientists and doctors alike. 

Researchers Colin Bantle and colleagues primarily from the Department of Environmental and Radiological Health Sciences at Colorado State University, USA, set out to address these gaps. They published their findings in 2019 in the npj Parkinson's Disease journal. They were interested in Viral Parkinsonism caused by Western Equine Encephalitis Virus (WEEV), one of many viral infections known to cause encephalitis. WEEV is transmitted by mosquitoes, and can cause disease in a number of hosts including humans and horses. The worst WEEV outbreak recorded occurred in 1941, with over 3,000 confirmed human cases on record. In the last 50 years, approximately 700 symptomatic cases have been reported in the USA alone, with twice as many women as men affected

Bantle and colleagues were able to show that WEEV delivered through the nose of lab mice could cause 100% lethality in the mice. They then prevented this high mortality by introducing immunotherapy in the form of serum to allow the mice to recover. Serum isolated from blood of recovered animals carries antibodies to infection, which can help an animal fight off an overwhelming viral infection. This animal model now serves as a mimicry of human infection and recovery from WEEV. This could solve the animal model barrier for future research of a variety of disorders, including Viral Parkinsonism, Parkinson's Disease, and many others. 

A small brown mouse held in the palm of a hand.

 These little mice could hold the answers to how Viral Parkinsonism can arise from a viral infection.

 Rama on Wikimedia Commons

Spread of WEEV in the mice was extremely rapid, with untreated mice (those not receiving serum treatment) not surviving longer than 96 hours post-infection. The virus quickly moved from the nose to the brain, where it caused hypokinesia (decreased bodily movement), lethargy (activity decrease due to tiredness), and hunched posture (a symptom of infection and illness in lab mice). A loss of dopamine neurons in the brain was also seen within 4 days of infection, a hallmark of Parkinson's-like neurological dysfunction development.

Brain images of infected mice showed infection of the substantia nigra (an important structure for movement), and ventral tegmental area (the area of the brain responsible for dopamine production and circulation). Loss of dopaminergic neurons (neurons, or signal-transducing brain cells that transmit dopamine) are also a hallmark sign of Parkinson's-like disease progression.

Michael J Fox on stage

In the USA alone, over 50,000 people are diagnosed with Parkinson's disease each year, where people with Parkinson's include actor Michael J. Fox.

 Paul Hudson on Flickr

An increase in microglia levels is also a hallmark of Parkinson's-like disease progression. Microglia are a type of immune cell in the central nervous system, and one of the first contacts of invading pathogens, such as viruses. So, an increased level of these immune "superheros" indicate a disease of the central nervous system, including the brain. In this study, Bantle and colleagues found a 31-46% increase in microglia throughout the brain, indicating infection of the central nervous system. An increase in astrocytes (similar to microglia, these are another first-responder immune cell of the central nervous system) was also noted to increase 56-79% in various areas of the brain. What this virus has in common with other Parkinsonism-inducing viruses is that they are all capable of directly infecting the brain, leading researchers to believe that central nervous system viral infections can often to lead to development of a Parkinson's-like disease later in life.

One fact all scientists can agree on is that protein aggregates in the brain, specifically alpha-synuclein aggregates post-infection are almost always present in Parkinson's Disease development. Consistent with previous findings, Bantle et al. also found these alpha-synuclein aggregates in the brains of surviving mice (those that had been infected with WEEV then treated with serum immunotherapy).

The first is the new potential mouse model for study of Viral Parkinsonism. Researchers were able to stimulate disease symptoms in mice exclusively in the brain. This strengthens the model for research, as widespread disease would be difficult to study (when everything is infected, it's hard to narrow down results to a specific area and function, in addition to the fact that Viral Parkinsonism is seems to be stimulated by encephalitis, which is exclusive to the brain).

The researchers suggest that the increased number of immune cells in the brain could promote inflammation, causing more damage post-infection, also potentially leading to Viral Parkinsonism. The final findings together suggest that the loss of dopamine-producing nerve cells combined with alpha-synuclein aggregates from the viral infection partially explain how encephalitis from a virus can lead to Viral Parkinsonism later in life. 

Though we know there is a connection between these viral infections and disease progression decades later, many mechanisms remain unknown. However, this study suggests a potential new cause of Viral Parkinsonism, and presents a new animal model for future research. In the USA alone, over 50,000 people are diagnosed with Parkinson's disease each year, 10-15% of whom are Parkinsonisms, diseases that share Parkinson's-like symptoms but progress more quickly, a category that includes Viral Parkinsonism. This study could pave the way for future research on how we can prevent encephalitis from leading to future brain disease, restoring quality of life to those suffering from the condition. 

]]> Tue, 19 Nov 2019 08:25:00 EST CRISPR technology for human gene editing is promising, but serious scientific and ethical concerns remain Multiple sectors of society must be involved in the regulation and applications of CRISPR to medicine striped bar pattern red, yellow, and white bars arranged in a pattern CRISPR-Cas9 has received global attention for its potential to  eliminate genetic disorders, infectious diseases, and many other  ailments that plague humans (pun intended). But in the realm of science, when something seems too good to be true, there are often important caveats. The current standing of gene editing technologies leaves many scientists wondering if we know enough about the genome and consequences of “genetic tampering” to do it in the name of betterment of mankind. 




]]> Sun, 13 Oct 2019 22:52:00 EST Pregnant women must get their flu shots to help avoid future influenza epidemics The flu virus treats the altered immune systems of pregnant individuals as its training ground to get stronger, making vaccination an imperative pregnancy pregnant woman standing against a black background Marnie Willman The international healthcare and economic burden of influenza in the United States alone is approximately $11.2 billion annually. Our best defense, the flu shot, takes almost a full year of planning to produce, made by groups such as the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC). This flu shot is generated months in advance of flu season (which runs from October to March in North America), based on the three "biggest risk" strains in southern hemisphere countries that have already experienced their flu season for the year.

Contrary to popular belief, the flu shot does not have any live influenza virus in it. Exposure to dead flu virus particles stimulates an immune response, and makes immune cells and antibodies able to fight off the virus. These antibodies are "remembered" by the immune system, so that if your body comes in contact with that particular flu strain again, it has specialized immune cells waiting in the wings to quickly combat the invader. Some people may feel slightly ill or warm after getting their flu shot, but this is the immune system building up its defense for future fights against this bug, not an actual flu infection itself. 

Given this potential protection, it is surprising that the proportion of people who get the flu shot in a given season is low in North American countries, where the shot is readily available. During the U.S. 2017-2018 influenza season, just 45-50% of the U.S. population reported getting their flu shot. Vaccination rates in Canada are even lower, at approximately 37% of the population. 

Vaccination rates matter because those of us who do get our flu shots protect those who are unable to get the shot for medical reasons, like immunocompromised individuals. This is called "herd immunity", meaning that enough people in a population are vaccinated to protect the unimmunized from getting the flu. The vaccination rate required to achieve herd immunity for flu is about 80%, far greater than current vaccination rates in the U.S. and Canada. 

There are two predominant vaccine formulations available in North America: a live, weakened version of the virus (for example FluMist, available as a nasal spray), and a killed, injectable vaccine (the flu shot). While women are not encouraged by healthcare professionals to get the live vaccine during pregnancy, it is safe for them to receive the killed vaccine. Because their bodies need to protect the growing fetus as well as themselves, pregnant women have altered immune responses compared to non-pregnant individuals that make them more susceptible to severe influenza infection.

In a study published in the journal Cell Host and Microbe at the end of the 2016-2017 flu season, a team of German scientists led by Géraldine Engels set out to understand how pregnant women's bodies respond to flu infections. They infected pregnant mice with the H1N1 flu strain (commonly known as Swine Flu) to test their immune responses to the virus. They measured amounts of several immune cells and the amount of virus detected in the lung tissue of the pregnant mice after infection. They found that that pregnant mice tended to harbor more virulent (i.e. more harmful) flu viruses than non-pregnant mice. In other words, the viruses are able to take advantage of a "distracted" host immune system and turn the body into their playground, becoming more pathogenic and capable of causing severe disease as they replicate.

a smiling baby getting a shot

Getting a flu shot is safe and important for healthy people of all ages

Heather Hazzan, SELF Magazine 

The results of this study make the problem of low vaccination rates even more alarming. The CDC reported a vaccination rate of approximately 54% for pregnant women in the U.S., similar to the national average, but according to Engels' research, the remaining 46% of unvaccinated pregnant women may be at higher-than-average risk of passing more dangerous flu viruses to others.

A large reason why many people in developed countries do not vaccinate against seasonal influenza is because they believe it is a low threat virus. We vaccinate for chicken pox, measles, mumps, and polio because they are life-threatening illnesses, but are less fearful of the flu because it has a low death rate among healthy people. But practice makes perfect, and viruses get a lot of practice, randomly swapping out different genetic information across generations to get the perfect combination to infect as many hosts as possible. The flu this year is different from the flu of last year, and some strains of flu can lead to high death rates even in healthy people.

Some propaganda says the influenza vaccine is harmful to pregnant mothers and developing fetuses. But many clinical studies have shown that these side-effects are not linked to the seasonal flu shot. The CDC advises women at any stage of their pregnancy to receive the seasonal influenza vaccination, due to the many adverse effects that influenza infection can have on a fetus, such as neural tube defects, a serious and often fatal developmental problem.

Prevention is key when it comes to influenza infections, particularly seasonal influenza. Even if you got your flu shot last year, you should know that the dominant seasonal flu strains change from year-to-year, so each year is a fresh slate. Getting your vaccination is as important for those who cannot be vaccinated as it is for you. The flu shot is low-cost, readily available, and safe for pregnant and non-pregnant individuals alike. The power to prevent the next deadly flu epidemic — and protect the next generation — could be in your (pharmacist's) hands. 

]]> Sat, 14 Sep 2019 13:00:00 EST The rise of a mysterious lung illness begins to expose the dangers of vaping The U.S. Centers for Disease Control have reported at least 450 cases in 33 U.S. states, as policy makers call for action vaping a woman against a gray background blowing smoke Walking through a park, across a street, or heading to work, all of us have suddenly caught the scent of fruit, chocolate, peppermint, or some other flavor coming from someone vaping nearby. As vaping has rapidly gained popularity since it’s invention in 2003, little has been said or written about its potentially dangerous health impacts. Many shops and restaurants in the U.S. and Canada have banned vaping on patios, near doors of establishments, and other public areas where smoking cigarettes is not permitted. Now, vapes have made the news in a negative light for the second time.

 As CBC reported on August 23, 2019, an Illinois resident passed away following severe respiratory illness likely brought on by vaping, according to the U.S. Centers for Disease Control. Currently, the CDC is investigating at least 450 cases of severe respiratory illness across 33 states, all thought to be related to chronic vape use. The cause is yet unknown, and Canada's chief public health officer, Dr. Theresa Tam, reported to the media that the mysterious illness has not yet reached Canada. Tam also cautioned that everyone should be aware that the long-term effects of vaping, given that the number of chemical ingredients in vape oils, are unknown. 

We may not know the exact link between vaping and this lung disease, but we do know some things about the dangers of vaping. Vaping entails inhaling steam and other chemicals, like formaldehyde, into the lungs. Human lungs are coated with mucus inside that protects lung cells by catching particulates before they infiltrate the rest of the body. Exposure to these particles thickens the mucus layer inside the lungs, decreasing the lungs' ability to fight off respiratory infections. Inhaling steam also prevents the lungs from absorbing as much oxygen as they should.  Lower oxygen levels in the body decreases the health and functioning of major organs and muscles. In addition to these, the negative effects of ingredients in vape oil remain unknown and/or unreported.

These health risks of inhaling a foreign substance of any kind into your lungs point to potential dangers of long-term vaping use. While the cause of death and illness in individuals who vape isn't exactly clear yet, one thing is certain: Health officials and policy makers — and even Donald Trump — are beginning to worry about the correlation between the illnesses and increased vape use. We are probably just seeing the beginning of vaping-related diseases and deaths.

]]> Fri, 16 Aug 2019 10:04:00 EST A good defense is the best offense in medicine It may be perceived as "boring" or "routine," but preventative medicine should be a priority in today's health care system two women talking two women siting in a large bright room and one is taking notes A largely overlooked area of modern medicine is preventative medicine. In medical schools and rehabilitation fields, we are trained to fix problems, a skill which is hard to apply if the problem is still in the future. However, that is not the way that medicine used to be. Historically, the town doctor took time to know their patients and understand their lifestyle, which was possible because they interacted with their patients more frequently, both personally and professionally, than doctors do today. And while (or, perhaps, because) we see the doctor less than ever before, the collective health of the U.S. population is consistently poor. In fact, every year since 2004, the U.S. has come in last place in terms of life expectancy among the top 11 industrialized countries in the world.

