By Shawn Kennedy, AJN editor-in-chief. Accompanying map via PAHO/WHO.
The media is full of headlines and photos about the recent increase in the number of Brazilian children born with microcephaly, thought to be due to maternal exposure to the Zika virus. If you’re like most nurses, you’ve had family members and friends asking you about it, especially if they’re considering a winter escape to the Caribbean or Mexico. Here are some resources and information to help you stay up to date so you can provide your patients (and families and neighbors) with evidence-based information.
Zika basics. Zika virus was first discovered in 1947 in monkeys in the Zika forest of Uganda and the first documented case in humans was in 1952. An outbreak on Yap Island in Micronesia in 2007 showed that it had spread beyond Africa. The virus is spread by the Aedes mosquito, the same mosquito that transmits yellow fever, dengue, and chikungunya.
Outbreaks of Zika have been spreading northward from Brazil through the Americas since 2014. (See above PAHO/WHO map of confirmed cases, 2015-2016.) While most transmission is believed to occur via mosquito bites, according to the CDC, “Perinatal, in utero, and possible sexual and transfusion transmission events have also been reported. Zika virus RNA has been identified in asymptomatic blood donors during an ongoing outbreak.”
Symptoms and course are similar to those of other viruses: a few days to a week of fever, headache, arthralgia, rash. Conjunctivitis has also been reported. Treatment is usually limited to supportive care (fluids, rest, etc). Only one-fifth of those infected become symptomatic, and death is rare. However, outbreaks of Zika virus have also been recently associated with neurologic syndromes (Guillain-Barré, meningitis, meningoencephalitis, myelitis).
Zika and pregnancy: emerging concerns. Everyone paid attention when, in late 2015, Brazil reported a sharp increase in the number of infants born with microcephaly. According to reports from WHO, from 2010 to 2014 the national average number of microcephalic infants born was 163. But in 2015, there were 3,530, with most occurring in northeast Brazil and late in the year. Zika virus was found during autopsy in microcephalic infants with other anomalies and in the amniotic fluid of some of the mothers, suggesting an association. (It’s important to note, however, that there may be other factors involved, given the clustering of cases in northeast Brazil while increased incidence of microcephaly have not been widely reported elsewhere. This is an evolving story and the investigation is ongoing.) Read the rest of this entry ?