Zika Virus

As you may or may not be aware, the Centers for Disease Control and Prevention (CDC) recently issued a Health Advisory for travelers going to and from Central and South America, the Caribbean, Mexico, and Puerto Rico regarding the Zika virus.  Zika virus outbreaks have previously been reported in Africa, Asia, and islands in the Pacific.  The Zika virus is a mosquito-borne virus transmitted primarily by Aedes aegypti; Aedes albopictus mosquitoes might also transmit the virus.  Local transmission of the Zika virus has not been documented in the continental United States.  However, Zika virus infections have been reported in travelers returning to the United States from areas where infection has been identified.  There is some concern that imported cases may result in local spread of the virus in some areas of the continental United States, meaning the imported cases may result in human-to-mosquito-to human spread of the virus.  Experts believe additional spread is likely because the Aedes species mosquitoes that spread the virus are found in many locations throughout the world.

About one in five people infected with Zika virus become symptomatic, and those that do may see symptoms such as a fever, rash, joint pain, or conjunctivitis (pink eye) within 2 to 7 days of being bitten by an infected mosquito.  Clinical illness is usually mild, with symptoms lasting for several days to a week.  Severe disease requiring hospitalization is uncommon and fatalities are rare.  During the current outbreak in Brazil, Zika virus RNA (Ribonucleic acid) has been identified in tissues from several infants with microcephaly (smaller than normal heads as a result of abnormal brain development) and following fetal deaths in women infected during pregnancy.  The Brazil Ministry of Health has reported a marked increase in the number of babies born with microcephaly.  However, it is not known how many of the microcephaly cases are associated with Zika virus infection and what factors increase risk to the fetus.

No specific antiviral treatment is available for Zika virus disease.  Treatment is generally supportive and can include rest, fluids, and use of analgesics and antipyretics.  Because of similar geographic distribution and symptoms, patients with suspected Zika virus infections should also be evaluated and managed for possible dengue or chikungunya virus infection.

The CDC Health Advisory includes information and recommendations about Zika virus clinical disease, diagnosis, and prevention, and provides travel guidance for pregnant women and women who are trying to become pregnant.  Until more is known, and out of an abundance of caution, pregnant women and women of childbearing age should consider postponing travel to any area where Zika virus transmission is ongoing.  Pregnant women who do travel to these areas should talk to their doctors or other healthcare providers first and strictly follow steps to avoid mosquito bites during the trip.  Women trying to become pregnant should consult with their healthcare providers before traveling to these areas and strictly follow steps to avoid mosquito bites during the trip.  Zika virus usually remains in the blood of an infected person for only a few days to a week.  The virus will not cause infections in a baby that is conceived after the virus is cleared from the blood. 

No vaccine or preventive drug is available.  The best way to prevent Zika virus infection is to:

·         Avoid mosquito bites.

·         Use air conditioning or window and door screens when indoors.

·         Wear long-sleeved shirts, long pants, socks, and shoes.

·         Use Environmental Protection Agency (EPA)-registered insect repellants, as appropriate for you and according to product directions, when outdoors.  Most repellents, including DEET, can be used on children older than 2 months.  Pregnant and lactating women can use all EPA-registered insect repellents, including DEET, according to the product label.

For more information on the Zika virus, you can visit the CDC’s “Zika Virus” webpage at:  http://www.cdc.gov/zika/index.html/.  You can access the full CDC Health Advisory at:  http://emergency.cdc.gov/han/han00385.asp.