zika fever zika fever zika fever, also known as zika virus disease or simply zika, is an infectious disease caused by the zika virus. most cases have no symptoms, but when present they are usually mild and can resemble dengue fever. symptoms may include fever, red eyes, joint pain, headache, and a maculopapular rash. symptoms generally last less than seven days. it has not caused any reported deaths during the initial infection. mother-to-child transmission during pregnancy can cause microcephaly and other brain malformations in some babies. infections in adults have been linked to guillain–barré syndrome (gbs). zika feverother nameszika virus disease, zika, zika virus infectionrash during zika fever infectionpronunciationzika /ˈziːkə/ specialtyinfectious diseasesymptomsfever, red eyes, joint pain, headache, maculopapular rash, sometimes nonecomplicationsguillain–barré syndrome, during pregnancy can cause microcephaly in the babydurationshort-termcauseszika virus mainly spread by mosquitoes, can also be sexually transmitteddiagnostic methodtesting blood, urine, or saliva for viral rna or blood for antibodiesdifferential diagnosischikungunya, malaria, dengue, leptospirosis, measlespreventionpermethrin, deet, picaridin, male condomstreatmentsupportive care, generally not needed in mild casesdeaths≥ 51 (2016–19) zika fever is mainly spread via the bite of mosquitoes of the aedes type. it can also be sexually transmitted and potentially spread by blood transfusions. infections in pregnant women can spread to the baby. diagnosis is by testing the blood, urine, or saliva for the presence of the virus's rna when the person is sick, or the blood for antibodies after symptoms are present more than a week. prevention involves decreasing mosquito bites in areas where the disease occurs and proper use of condoms. efforts to prevent bites include the use of insect repellent, covering much of the body with clothing, mosquito nets, and getting rid of standing water where mosquitoes reproduce. there is no effective vaccine. health officials recommended that women in areas affected by the 2015–16 zika outbreak consider putting off pregnancy and that pregnant women not travel to these areas. while there is no specific treatment, paracetamol (acetaminophen) may help with the symptoms. admission to hospital is rarely necessary. the virus that causes the disease was first isolated in africa in 1947. the first documented outbreak among people occurred in 2007 in the federated states of micronesia. an outbreak started in brazil in 2015, and spread to the americas, pacific, asia, and africa. this led the world health organization to declare it a public health emergency of international concern in february 2016. the emergency was lifted in november 2016, but 84 countries still reported cases as of march 2017. the last proven case of zika spread in the continental united states was in 2017. signs and symptoms rash on an arm due to zika fever most people who are infected have no or few symptoms. otherwise the most common signs and symptoms of zika fever are fever, rash, conjunctivitis (red eyes), muscle and joint pain, and headache, which are similar to signs and symptoms of dengue and chikungunya fever. the time from a mosquito bite to developing symptoms is not yet known, but is probably a few days to a week. the disease lasts for several days to a week and is usually mild enough that people do not have to go to a hospital. due to being in the same family as dengue, there has been concern that it could cause similar bleeding disorders. however that has only been documented in one case, with blood seen in semen, also known as hematospermia. guillain–barré syndrome zika virus infections have been strongly associated with guillain–barré syndrome (gbs), which is a rapid onset of muscle weakness caused by the immune system damaging the peripheral nervous system, and which can progress to paralysis. while both gbs and zika infection can simultaneously occur in the same individual, it is difficult to definitively identify zika virus as the cause of gbs. though zika virus has been shown to infect human schwann cells. several countries affected by zika outbreaks have reported increases in the rate of new cases of gbs. during the 2013–2014 outbreak in french polynesia there were 42 reported cases of gbs over a 3-month period, compared to between 3 and 10 annually prior to the outbreak. pregnancy microcephaly