This vaccine consists of a small circular piece of dna, known as a plasmid, that expresses the genes for the zika virus envelope proteins. As the vaccine does not contain the full sequence of the virus, it cannot cause infection. 73 As of April 2017, both subunit and inactivated vaccines have entered clinical trials. 74 History edit see also: zika fever Epidemiology, and zika virus outbreak timeline countries that have past or current evidence of zika transmission (as of January 2016) 75 Spread of zika in Africa and Asia, based on molecular sequence data. 78 Virus isolation in monkeys and mosquitoes, 1947 edit The virus was first isolated in April 1947 from a rhesus macaque monkey placed in a cage in the ziika forest of Uganda, huidzorg near lake victoria, by the scientists of the yellow fever Research Institute. 79 A second isolation from the mosquito. Africanus followed at the same site in January 1948. 80 When the monkey developed a fever, researchers isolated from its serum a "filterable transmissible agent" which was named zika in 1948. 81 First evidence of human infection, 1952 edit zika was first known to infect humans from the results of a serological survey in Uganda, published in 1952. 82 Of 99 human sera tested,.1 had neutralizing antibodies. As part of a 1954 outbreak investigation of jaundice suspected to be yellow fever, researchers reported isolation of the virus from a patient, 83 but the pathogen was later shown to be the closely related Spondweni virus.
Symptoms, zika virus, cDC
65 diagnosis is by testing the blood, urine, or saliva for the presence of zika virus rna when the person is sick. 64 66 Prevention involves decreasing mosquito bites in areas where the disease occurs, and proper use of condoms. 66 68 Efforts to prevent bites include the use of insect repellent, covering much of the body with oefeningen clothing, mosquito nets, and getting rid of standing water where mosquitoes reproduce. 64 There is no effective vaccine. 66 health officials recommended that women in areas affected by the 201516 zika outbreak consider putting off pregnancy and that pregnant women not travel to these areas. 66 69 While there is no specific treatment, paracetamol (acetaminophen) and rest may help with the symptoms. 66 Admission to hospital is rarely necessary. 65 Vaccine development edit main article: zika virus vaccine The world health Organization (WHO) has suggested that priority should be to develop inactivated vaccines and other non-live vaccines, which are safe to use in pregnant women. 70 As of March 2016, 18 companies and institutions were developing vaccines against zika but they state a vaccine is unlikely to be widely available for about ten years. 70 the fda granted the first approval for a human clinical trial for a zika vaccine. 72 In March 2017, a dna vaccine was approved for phase 2 clinical trials.
After 510 days, the virus can be found in the mosquitos saliva. If the mosquitos saliva is inoculated into human skin, the virus can infect epidermal keratinocytes, skin fibroblasts in the skin and the langerhans cells. The pathogenesis of the virus is hypothesized to continue with a spread to lymph nodes and the bloodstream. 18 62 Flaviviruses replicate in the cytoplasm, but zika antigens have been found in infected cell nuclei. 63 zika fever edit main article: zika fever Rash on an arm due to zika zika fever (also known as zika virus disease) is an illness caused by the zika virus. 64 Most cases have no symptoms, but when present they are usually mild and can resemble dengue fever. 64 65 Symptoms may include fever, red eyes, joint pain, headache, and a maculopapular rash. Symptoms generally last less than seven days. 66 It has not caused any reported deaths during the initial infection. 65 Infection during pregnancy causes microcephaly and other brain malformations in some babies. 7 8 Infection in adults has been linked to guillainBarré syndrome (GBS).
Virus, symptoms, countries, risk, and Prevention
C., and genetic evidence suggests they survived at least four consecutive winters in the region. The study authors conclude that mosquitos are adapting for persistence in a northern climate. 51 The zika goji virus appears to be contagious via mosquitoes for around a week after infection. The virus is thought to be infectious for a longer period of time after infection (at least 2 weeks) when transmitted via semen. 52 53 Research into its ecological niche suggests that zika may be influenced to a greater degree by changes in precipitation and temperature than Dengue, making it more likely to be confined to tropical areas. However, rising global temperatures would allow for the disease vector to expand their range further north, allowing zika to follow. 54 Sexual edit zika can be transmitted from men and women to their sexual partners; most known cases involve transmission from symptomatic men to women. As of April 2016, sexual transmission of zika has been documented in six countries Argentina, chile, france, italy, new zealand, and the United States during the 2015 outbreak. 9 Since October 2016, the cdc has advised men who have traveled to an area with zika should use condoms or not have sex for at least six months after their return as the virus is still transmissible even if symptoms never develop. 57 Pregnancy edit The zika virus can spread by vertical (or "mother-to-child transmission, during pregnancy or at delivery. 58 7 Blood transfusion edit As of April 2016, two cases of zika transmission through blood transfusions have been reported globally, both from Brazil, 37 after which the us food and Drug Administration (FDA) recommended screening blood donors and deferring high-risk donors for 4 weeks. 59 60 A potential risk had been suspected based on a blood-donor screening study during the French Polynesian zika outbreak, in which.8 (42) of donors from november 2013 and February 2014 tested positive for zika rna and were all asymptomatic at the time.
Zika has been detected in many more species of Aedes, along with Anopheles coustani, mansonia uniformis, and Culex perfuscus, although this alone does not incriminate them as a vector. 45 Transmission. Albopictus, the tiger mosquito, was reported from a 2007 urban outbreak in Gabon where it had newly invaded the country and become the primary vector for the concomitant chikungunya and dengue virus outbreaks. 47 There is concern for autochthonous infections in urban areas of European countries infested. Albopictus because the first two cases of laboratory-confirmed zika infections imported into Italy were reported from viremic travelers returning from French Polynesia. 48 The potential societal risk of zika can be delimited by the distribution of the mosquito species that transmit. The global distribution of the most cited carrier of zika,. Aegypti, is expanding due to global trade and travel. Aegypti distribution is now the most extensive ever recorded across all continents including North America and even the european periphery ( Madeira, the netherlands, and the northeastern Black sea coast). 50 A mosquito population capable of carrying zika has been found in a capitol Hill neighborhood of Washington,.
Zika virus : Symptoms, facts, and diagnosis38 In 2015, news reports drew attention to the rapid spread of zika in Latin America and the caribbean. 39 At that time, the pan American health Organization published a list of countries and territories that experienced "local zika virus transmission" comprising Barbados, bolivia, brazil, colombia, the dominican Republic, Ecuador, El Salvador, French guiana, guadeloupe, guatemala, guyana, haiti, honduras, martinique, mexico, panama, paraguay, puerto. By august 2016, more than 50 countries had experienced active (local) transmission of zika virus. 43 Mosquito edit Global Aedes aegypti predicted distribution. The hals map depicts the probability of occurrence (bluenone, redhighest occurrence). Zika is primarily spread by the female aedes aegypti mosquito, which is active mostly in the daytime. 44 45 The mosquitos must feed on blood in order to lay eggs. 46 :2 The virus has also been isolated from a number of arboreal mosquito species in the genus Aedes, such. Vittatus, with an extrinsic incubation period in mosquitoes of about 10 days. 21 The true extent of the vectors is still unknown.
Once the cell has been infected, the virus restructures the endoplasmic reticulum, forming the large vacuoles, resulting in cell death. 28 There are two zika lineages: the African lineage and the Asian lineage. 29 Phylogenetic studies indicate that the virus spreading in the Americas is 89 identical to African genotypes, but is most closely related to the Asian strain that circulated in French Polynesia during the outbreak. The Asian strain appears to have evolved about 1939. 32 Transmission edit The vertebrate hosts of the virus were primarily monkeys in a so-called enzootic mosquito-monkey-mosquito cycle, with only occasional transmission to humans. Before the current pandemic began in 2007, zika "rarely caused recognized 'spillover' infections in humans, even in highly enzootic areas". Infrequently, however, other arboviruses have become established as a human disease and spread in a mosquitohumanmosquito cycle, like the yellow fever virus and the dengue fever virus (both flaviviruses and the chikungunya virus (a togavirus ). 33 Though the reason for the pandemic is unknown, dengue, a related arbovirus that infects the same species of mosquito vectors, is known in particular price to be intensified by urbanization and globalization. 34 zika is primarily spread by aedes aegypti mosquitoes, 35 and can also be transmitted through sexual contact 36 or blood transfusions. 37 The basic reproduction number ( R 0, a measure of transmissibility) of zika virus has been estimated to be between.4 and.6.
Zika, virus 6 Antworten zu, symptomen vorbeugung!
As in other flaviviruses, such haar as the similarly sized West Nile virus, the rna genome encodes seven nonstructural proteins and three structural proteins. 24 One of the structural proteins encapsulates the virus. This protein is the flavivirus envelope glycoprotein, that binds to the endosomal membrane of the host cell to initiate endocytosis. 25 The rna genome forms a nucleocapsid along with copies of the 12-kda capsid protein. The nucleocapsid, in turn, is enveloped within a host-derived membrane modified with two viral glycoproteins. Viral genome replication depends on the making of double stranded rna from the single stranded positive sense rna (ssrna genome followed by transcription and replication to provide viral mRNAs and new ssrna genomes. 26 27 A longitudinal study shows that 6 hours after cells are infected with the zika virus, the vacuoles and mitochondria in the cells begin to swell. This swelling becomes so severe, it results in cell death, also known as paraptosis. This form of programmed cell death requires gene expression. Ifitm3 is a trans-membrane protein in a cell that is able to protect it from viral infection by blocking virus attachment. Cells are most susceptible to zika infection when levels of ifitm3 are low.
This can result in microcephaly, severe brain malformations, and other birth defects. 7 8 zika infections in adults may result rarely in guillainBarré syndrome. 9 In January 2016, the United States Centers for Disease control and Prevention (CDC) issued travel guidance on affected countries, including the use of enhanced precautions, and guidelines for pregnant women including considering postponing travel. 10 11 Other governments or health agencies also issued similar travel warnings, while colombia, the dominican mellékhatásai Republic, puerto rico, ecuador, el Salvador, and Jamaica advised women to postpone clinic getting pregnant until more is known about the risks. 13 15 zika is pronounced /zikə/ or /zɪkə/. 16 17 Contents Virology edit The zika virus belongs to the family Flaviviridae family and the genus Flavivirus, and is thus related to the dengue, yellow fever, japanese encephalitis, and West Nile viruses. Like other flaviviruses, zika virus is enveloped and icosahedral and has a nonsegmented, single-stranded, 10 kilobase positive-sense rna genome. It is most closely related to the Spondweni virus and is one of the two known viruses in the Spondweni virus clade. Cross-section of zika virus, showing the viral envelope composed of envelope proteins (red) and membrane proteins (purple) embedded in the lipid membrane (white).The capsid proteins (orange) are shown interacting with the rna genome (yellow) at the center of the virus. 23 A positive-sense rna genome can be directly translated into viral proteins.
Zika, virus -Infektion: Symptome, risiken, Ansteckungsgefahr - netDoktor
This article is about the virus. For the disease, see. For the recent outbreak, see 201516 zika virus epidemic. Zika virus zikv ) is a member of the virus family, flaviviridae. 3, it is spread by daytime-active, aedes mosquitoes, such as,. 3, its name comes from the, ziika forest of Uganda, where the virus was first isolated in 1947. Zika virus is related to the dengue, yellow fever, japanese encephalitis, and, west Nile viruses. 4, since the 1950s, it has been known to occur within a narrow equatorial belt from Africa to Asia. From 2007 to 2016, the virus spread eastward, across the pacific Ocean to the Americas, leading to the 201516 zika virus epidemic. 5, the infection, known as, zika fever or zika virus disease, often causes pillen no or only mild symptoms, similar to a very mild form of dengue fever. 3 While there is no specific treatment, paracetamol (acetaminophen) and rest may help with the symptoms., the illness cannot be prevented by medications or vaccines. 6 zika can spread from a pregnant woman to her baby.