adapted to running water. eggs of species of mosquitoes from the temperate zones are more tolerant of cold than the eggs of species indigenous to warmer regions. many even tolerate subzero temperatures. in addition, adults of some species can survive the winter by taking shelter in suitable microhabitats such as buildings or hollow trees. pollination several flowers are pollinated by mosquitoes, including some members of the asteraceae, rosaceae and orchidaceae. activity in warm and humid tropical regions, some mosquito species are active for the entire year, but in temperate and cold regions they hibernate or enter diapause. arctic or subarctic mosquitoes, like some other arctic midges in families such as simuliidae and ceratopogonidae may be active for only a few weeks annually as melt-water pools form on the permafrost. during that time, though, they emerge in huge numbers in some regions and may take up to 300 ml of blood per day from each animal in a caribou herd. means of dispersal worldwide introduction of various mosquito species over large distances into regions where they are not indigenous has occurred through human agencies, primarily on sea routes, in which the eggs, larvae, and pupae inhabiting water-filled used tires and cut flowers are transported. they have also been carried by personal vehicles, delivery trucks, trains, and aircraft. man-made areas such as storm water retention basins, or storm drains also provide sprawling sanctuaries. sufficient quarantine measures have proven difficult to implement. in addition, outdoor pool areas make a perfect place for them to grow. seasonality in order for a mosquito to transmit a disease to the host there must be favorable conditions, referred to as transmission seasonality. seasonal factors that impact the prevalence of mosquitoes and mosquito-borne diseases are primarily humidity, temperature, and precipitation. a positive correlation between malaria outbreaks and these climatic variables has been demonstrated in china; and el niño has been shown to impact the location and number of outbreaks of mosquito-borne diseases observed in east africa, latin america, southeast asia and india. climate change impacts each of these seasonal factors and in turn impacts the dispersal of mosquitoes. past and future patterns climatology and the study of mosquito-borne disease have been developed only over the past 100 years. historical records of weather patterns and distinct symptoms associated with mosquito-borne diseases can be utilized to trace the prevalence of these diseases in relation to the climate over longer time periods. further, statistical models are being created to predict the impact of climate change on vector-borne diseases using these records, and these models can be utilized in the field of public health in order to create interventions to reduce the impact of these predicted outcomes. two types of models are used to predict mosquito-borne disease spread in relation to climate: correlative models and mechanistic models. correlative models focus primarily on vector distribution, and generally function in 3 steps. first, data is collected regarding geographical location of a target mosquito species. next, a multivariate regression model establishes the conditions under which the target species can survive. finally, the model determines the likelihood of the mosquito species to become established in a new location based on similar living conditions. the model can further predict future distributions based on environmental emissions data. mechanistic models tend to be broader and include the pathogens and hosts in the analysis. these models have been used to recreate past outbreaks as well as predict the potential risk of a vector-borne disease based on an areas forecasted climate. mosquito-borne diseases are currently most prevalent in east africa, latin america, southeast asia, and india. an emergence in europe was recently observed. a weighted risk analysis demonstrated associations to climate for 49% of infectious diseases in europe including all transmission routes. one statistical model predicts by 2030, the climate of southern great britain will be climatically suitable for malaria transmission plasmodium vivax for 2 months of the year. by 2080 it is predicted that the same will be true for southern scotland. vectors of disease anopheles albimanus mosquito feeding on a human arm – anopheline mosquitoes are the only vectors of malaria, so mosquito control is a very effective way of reducing the incidence. main article: mosquito-borne disease mosquitoes can act as vectors for many disease-causing viruses and parasites. infected mosquitoes carry these organisms from person to person without exhibiting symptoms themselves. mosquito-borne diseases include: viral diseases, such as yellow fever, dengue fever, and chikungunya, transmitted mostly by aedes aegypti. dengue fever is the most common cause of fever in travelers returning from the caribbean, central america, south america, and south central asia. this disease is spread through the bites of infected mosquitoes and cannot be spread person to person. severe dengue can be fatal, but with good treatment, fewer than 1% of patients die from dengue. work published in 2012 from baylor college of medicine suggested that for some diseases, such as dengue fever, which can be transmitted via mosquitoes and by other means, the severity of the mosquito-transmitted disease could be greater. the parasitic diseases collectively called malaria, caused by various species of plasmodium, carried by female mosquitoes of the genus anopheles. lymphatic filariasis (the main cause of elephantiasis) which can be spread by a wide variety of mosquito species. west nile virus is a significant concern in the united states but there are no reliable statistics on worldwide cases. dengue viruses are a significant health risk globally. severe cases of dengue often require hospitalization and can be life-threatening shortly after infection. symptoms include a high fever, aches and pains, vomiting, and rashes. warning signs of severe dengue infection include vomiting blood, bleeding from the gums or nose, and stomach tenderness/pain. equine encephalitis viruses, such as eastern equine encephalitis virus, western equine encephalitis virus, and venezuelan equine encephalitis virus, can be spread by mosquito vectors such as aedes taeniorhynchus. tularemia, a bacterial disease caused by francisella tularensis, is variously transmitted, including by biting flies. culex and culiseta are vectors of tularemia, as well as arbovirus infections such as west nile virus. zika, recently notorious, though rarely deadly, causes fever, joint pain, rashes and conjunctivitis. the most serious consequence appears when the infected person is a pregnant woman, since during pregnancy this virus can originate a birth defect called microcephaly. st. louis encephalitis, a mosquito-borne disease that is characterized by fever and headaches upon initial onset of infection, arises from mosquitoes who feed on birds who are infected with the illness, and can result in death. the most common vector of this disease is culex pipiens, also known as the common house mosquito. heartworm disease, a parasitic roundworm infection that affects dogs and other canids. mosquitoes transmit larvae to the definitive host through bites. adult heart worms infest the right heart and pulmonary artery, where they can cause serious complications including congestive heart failure. potential transmission of hiv was originally a public health concern, but practical considerations and detailed studies of epidemiological patterns suggest that any transmission of the hiv virus by mosquitoes is at worst extremely unlikely. various species of mosquitoes are estimated to transmit various types of disease to more than 700 million people annually in africa, south america, central america, mexico, russia, and much of asia, with millions of resultant deaths. at least two million people annually die of these diseases, and the morbidity rates are many times higher still. methods used to prevent the spread of disease, or to protect individuals in areas where disease is endemic, include: vector control aimed at mosquito control or eradication disease prevention, using prophylactic drugs and developing vaccines prevention of mosquito bites, with insecticides, nets, and repellents since most such diseases are carried by "elderly" female mosquitoes, some scientists have suggested focusing on these to avoid the evolution of resistance. control main article: mosquito controlmosquitofish gambusia affinis, a natural mosquito predator many measures have been tried for mosquito control, including the elimination of breeding places, exclusion via window screens and mosquito nets, biological control with parasites such as fungi and nematodes, or predators such as fish, copepods, dragonfly nymphs and adults, and some species of lizard and gecko. another approach is to introduce large numbers of sterile males. genetic modification methods including cytoplasmic incompatibility, chromosomal translocations, sex distortion and gene replacement, solutions seen as inexpensive and not subject to vector resistance, have been explored. according to an article in nature discussing the idea of totally eradicating mosquitoes, "ultimately, there seem to be few things that mosquitoes do that other organisms can't do just as well—except perhaps for one. they are lethally efficient at sucking blood from one individual and mainlining it into another, providing an ideal route for the spread of pathogenic microbes." the control of disease-carrying mosquitoes may in the future be possible using gene drives. repellents main article: insect repellent mosquito repellents (including a mosquito coil) in a finnish store insect repellents are applied on skin and give short-term protection against mosquito bites. the chemical deet repels some mosquitoes and other insects. some cdc-recommended repellents are picaridin, eucalyptus oil (pmd), and ethyl butylacetylaminopropionate (ir3535). pyrethrum (from chrysanthemum species, particularly c. cinerariifolium and c. coccineum) has been reviewed favorably in research published in 2021. others are indalone, dimethyl phthalate, dimethyl carbate, and ethyl hexanediol. electronic insect repellent devices that produce ultrasounds intended to keep away insects (and mosquitoes) are marketed. no epa or university study has shown that these devices prevent a human from being bitten by a mosquito. bites main article: mosquito bite allergies mosquito bites lead to a variety of mild, occasionally serious, and, rarely, life-threatening allergic reactions. these include ordinary wheal and flare reactions and mosquito bite allergies (mba). the mba, also termed hypersensitivity to mosquito bites (hmb), are excessive reactions to mosquito bites that are not caused by any toxin or pathogen in the saliva injected by a mosquito at the time it takes its blood-meal. rather, they are allergic hypersensitivity reactions caused by the non-toxic allergenic proteins contained in the mosquito's saliva. studies have shown or suggest that numerous species of mosquitoes can trigger ordinary reactions as well as mba. these include aedes aegypti, aedes vexans, aedes albopictus, anopheles sinensis, culex pipiens, aedes communis, anopheles stephensi, culex quinquefasciatus, ochlerotatus triseriatus, and culex tritaeniorhynchus. furthermore, there is considerable cross-reactivity between the salivary proteins of mosquitoes in the same family and, to a lesser extent, different families. it is therefore assumed that these allergic responses may be caused by virtually any mosquito species (or other biting insect). a warning sign about mosquitoes in sodankylä, finland the mosquito bite allergies are informally classified as 1) the skeeter syndrome, i.e. severe local skin reactions sometimes associated with low-grade fever; 2) systemic reactions that range from high-grade fever, lymphadenopathy, abdominal pain, and/or diarrhea to, very rarely, life-threatening symptoms of anaphylaxis; and 3) severe and often systemic reactions occurring in individuals that have an epstein-barr virus-associated lymphoproliferative disease, epstein-barr virus-negative lymphoid malignancy, or another predisposing condition such as eosinophilic cellulitis or chronic lymphocytic leukemia. mechanism visible, irritating bites are due to an immune response from the binding of igg and ige antibodies to antigens in the mosquito's saliva. some of the sensitizing antigens are common to all mosquito species, whereas others are specific to certain species. there are both immediate hypersensitivity reactions (types i and iii) and delayed hypersensitivity reactions (type iv) to mosquito bites. both reactions result in itching, redness and swelling. immediate reactions develop within a few minutes of the bite and last for a few hours. delayed reactions take around a day to develop, and last for up to a week. treatment several anti-itch medications are commercially available, including those taken orally, such as diphenhydramine, or topically applied antihistamines and, for more severe cases, corticosteroids, such as hydrocortisone and triamcinolone. aqueous ammonia (3.6%) has also been shown to provide relief. both topical heat and cool may be useful to treat mosquito bites. in human culture greek mythology ancient greek beast fables including "the elephant and the mosquito" and "the bull and the mosquito", with the general moral that the large beast does not even notice the small one, derive ultimately from mesopotamia. origin myths the peoples of siberia have origin myths surrounding the mosquito. one ostiak myth tells of a man-eating giant, punegusse, who is killed by a hero but will not stay dead.