“Zika!” It started as a whisper and turned into a roar heard ‘round the globe. First discovered in the Zika Forest of Uganda in 1947, the mosquito-borne Zika virus has spread to more than 30 countries and territories in the Americas and South Pacific since being detected in Brazil in mid-2015. As of March 2, 2016, Zika had been linked in Brazil to more than 4,800 cases of microcephaly, a serious birth defect that in many cases hinders brain development. Last month the World Health Organization (WHO) officially declared the Zika outbreak to be an international public health emergency; the Centers for Disease Control and Prevention (CDC) has urged pregnant woman to avoid traveling to countries affected by Zika.
So, what do you need to know about the virus? Read on to get the bottom line about Zika.
How Zika Virus Spreads
Zika virus spreads primarily through bites from the Aedes aegypti mosquito, the same mosquito that spreads dengue and chikungunya infections. These mosquitoes mostly bite during the daytime but also bite at night. When an uninfected mosquito bites a person who has already been infected, this mosquito can then transmit the virus to others.
In terms of human-to-human transmission, Zika can be passed from mother to child during pregnancy and childbirth. Pregnancy-related complications from Zika will be discussed at length later in this article. In rare cases, a man can spread the virus through sexual intercourse. Doctors are currently investigating whether Zika can be spread through blood transfusions.
Symptoms, Diagnosis and Treatment
According to the CDC, common symptoms of Zika include fever, joint pain, conjunctivitis, headache and muscle pain. Since only 20 percent of people infected by Zika actually experience symptoms, people are often unaware that they’ve been infected. For those who do become ill, symptoms usually last for several days to a week.
Doctors can use a blood test to diagnose Zika. In the event of an infection, patients are encouraged to rest, drink lots of fluid and take a medication like acetaminophen to relieve pain and reduce fever. To prevent the further spread of the virus, infected people should take special precautions to avoid more mosquito bites during the first week of illness.
Besides microcephaly, Zika has also been linked to a nervous system disorder called Guillain-Barré syndrome, which causes muscle weakness and, in severe cases, temporary paralysis. While scientists are still working to confirm the link, it has been reported that countries heavily affected by Zika, including Brazil, Colombia and El Salvador, have seen a spike in cases of Guillain-Barré in recent weeks.
Zika Virus and Pregnancy
The “doença misteriosa” (mystery disease) crashed like a wave upon Recife, a city on Brazil’s northeastern coast. As described in the New York Times, in August 2015 doctors at hospitals around the city doctors began noticing an alarming trend: “[Babies] with normal faces up to the eyebrows, and then you have no foreheads and very strange heads.”
Soon, medical experts connected the rash of microcephaly cases in Recife with an illness that had been sweeping across the country: Zika. By the end of the year, some doctors in Recife and elsewhere were advising women to avoid getting pregnant until the Zika outbreak was over. Once Zika had spread beyond Brazil, health ministers in El Salvador called for women to delay pregnancy until 2018.
At present, the CDC is advising that women who are currently pregnant or are planning to have a baby avoid all areas affected by Zika (Full list here). The link between microcephaly and birth effects is suspected but not proven — yet. Complications of microcephaly, which causes a child to have a smaller than normal head, can range hearing and vision problems to intellectual disability, depending on the severity of the case. It also possible that there are no problems besides a smaller head size.
Because Zika virus can be passed from mother to child during pregnancy, women who have traveled to Zika-affected areas (and their male partners) should consult with their doctors, especially if they develop a rash or other symptoms within two weeks of returning the U.S.
Though there have yet to be any mosquito-borne Zika cases in the U.S., more than 100 people have been infected while traveling. The Zika risk is likely to increase as temperatures during the spring and summer.
Zika Virus Prevention
There is currently no vaccine or medication to treat the Zika virus. The best prevention method is to avoid mosquito bites. The CDC recommends wearing long-sleeved shirts and long pants, staying indoors in a place that has air conditioning and window and door screens, if possible. People should also use EPA-registered bug spray, which is safe for pregnant and breastfeeding women.
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