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zika
Verbete em inglês: https://en.wikipedia.org/wiki/Zika_virus
Verbete em francês: https://fr.wikipedia.org/wiki/Virus_Zika
Verbete em português: https://pt.wikipedia.org/wiki/V%C3%ADrus_Zika
Transmissão
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 virus "rarely caused recognized 'spillover' infections in humans, even in highly enzootic areas". Infrequently, other arboviruses have become established as a human disease though, and spread in a mosquito–human–mosquito cycle, like the yellow fever virus and the dengue fever virus ( both flaviruses), and the chikungunya virus (a togavirus).[8]
Os hospedeiros vertebrados do vírus foram primeiramente macacos na então chamado ciclo enzoótico mosquito-macaco-mosquito, com transmissão para humanos apenas ocasionalmente. Antes da atual pandemia iniciada em 2007, o vírus zica "raramente causou infecções 'por transpordamento' em humanos, mesmo em áreas altamente enzoóticas". Raramente, outros arbovirus tornaram-se estabelecidos como uma doença humana, e espalharam num ciclo mosquito-humano-mosquitoo, como o virus da febre amarela e o vírus da dengue (ambos flavivírus), e o virus chikingunya (um togavírus).
- spillover infections?
Vetor
The Zika virus is transmitted by daytime-active mosquitoes as its vector. It is primarily transmitted by Aedes aegypti, but has been isolated from a number of arboreal mosquito species in the Aedes genus, such as A. africanus, A. apicoargenteus, A. furcifer, A. hensilli, A. luteocephalus and A. vitattus with anextrinsic incubation period in mosquitoes of about 10 days.[23]
The true extent of the vectors is still unknown, as the Zika virus has been detected in many more species of Aedes, along with Anopheles coustani, Mansonia uniformis, and Culex perfuscus; though this alone does not incriminate them as a vector.[24]
O virus zica é transmitido por mosquitos ativos durante o dia com o seu vetor. É transmitido primariamente pelo Aedes aergypti, mas foi isolado em alguns mosquitos aboreais do 'genus'(?) Aedes, como ao Aedes africanus, o Aedes apicoargenteus, o Aedes Furcifer, o Aedes hensilli, o Aedes luteocephalus e o Aedes vitattus com um período de incubação 'anextrinsic' (?) em mosquitos em torno de 10 dias. A verdadeira extensão dos vetores ainda é desconhecida, já que o virus Zica foi detectado em muito mais espécies do Aedes, junto com o Anopheles cuostani, Mansonia uniformis, e o Culex perfuscus; embora este sozinho não os comprova(?) como um vetor.
Transmission by Aedes 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.[25] there is concern for autochthonous infections in urban areas of European countries infested by A. albopictus since the first two cases of laboratory confirmed Zika virus infections imported into Italy were reported from viremic travelers returning from French Polynesia.[26]
A transmissão pelo Aeder albopictus, o mosquito tigre(?), foi relatada a partir de um surto urbano no Gabão em 2007, onde ele havia invadido o país há pouco tempo e se tornado o vetor primário para os surtos concomitantes dos vírus da Chikunganya e da dengue. Há preocupaçao para infecçoes 'autochthnous' (?) em áreas urbanas de países europeus infestados pelo Aedes albopictus desde
The potential societal risk of Zika virus can be delimited by the distribution of the mosquito species that transmit it . The global distribution of the most cited carrier of Zika virus, A. aegypti, is expanding due to global trade and travel.[27] A. aegypti distribution is now the most extensive ever recorded – across all continents including North America and even the European periphery.[28] A mosquito population capable of carrying the Zika virus has been found in a Capitol Hill neighborhood of Washington, D.C., and genetic evidence suggests they survived at least the last four winters in the region. The study authors conclude that mosquitos are adapting for persistence in a northern climate.[29]
Since 2015 news reports have drawn attention to the spread of Zika in Latin America and the Caribbean.[30] The countries and territories that have been identified by the Pan American Health Organisation (PAHO) as having experienced "local Zika virus transmission" are Barbados, Bolivia, Brazil, Colombia, the Dominican Republic, Ecuador, El Salvador, French Guiana, Guadeloupe, Guatemala, Guyana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Saint Martin, Suriname, and Venezuela.[31][32]
Sexual
As of February 2016 five cases, reported only in symptomatic men, suggest Zika virus can be sexually transmitted. The first case was published by a biologist who after visiting Senegal in 2009 to study mosquitoes and was bitten, fell ill a few days after returning to the United States, but not before having had unprotected intercourse with his wife. She subsequently showed symptoms of Zika infection, and Zika antibodies confirmed the diagnosis in both the biologist's and his wife's blood.[33][34] The second case was reported in early February 2016 by the Dallas County Health and Human Services department after sexual contact with an ill person returning from a high risk country and is still under investigation.[35][36] The third case was the finding of Zika virus in semen and urine by RT-PCR of a Tahitian man two weeks and possibly up to 10 weeks after he fell ill with Zika, and had noticed blood in his semen. Zika virus grew from semen samples, but not blood or urine.[37]
Cases four and five are of Irish nationals who returned to Ireland from Dallas in February 2016.[38]
It is unknown whether women can transmit Zika virus to their sexual partners. As of February 2016, the CDC recommends that men living or having traveled to an area of active Zika virus transmission "should abstain from sexual activity or consistently and correctly use condoms during sex", while infected men and their non-pregnant sex partners should only "consider". The CDC did not specify how long to do so after the infection, as both incidence and duration of seminal shedding are unknown and that "testing of men for the purpose of assessing risk for sexual transmission is not recommended".[39]
Durante a gravidez
In 2015, Zika virus RNA was detected in the amniotic fluid of two fetuses, indicating that it had crossed the placenta and could cause a mother-to-child infection.[40] There is a possible link between Zika fever and abnormalities of brain (microcephaly) and eye in newborn babies by mother-to-child transmission.[5][6][7] On February 5, 2016 the CDC updated its health care provider guidelines for pregnant women in various scenarios of potential Zika virus exposure (travel, residence), newly recommending serologic testing to asymptomatic pregnant women with the start of prenatal care and follow-up testing mid-second trimester.[41]