Sexual transmission of Zika virus may be more frequent than previously reported

State health officials continue to provide information regarding Zika virus as more is learned about transmission and prevention of infections. Recent reports from the federal Centers for Disease Control and Prevention (CDC) suggest that sexual transmission from men to women may be more common than was known before the recent outbreak in the Americas.   


Zika virus is spread to people primarily through mosquito bites. While illness is usually mild, the possible link with birth defects and miscarriages makes prevention of infection among pregnant women essential. To avoid infections in pregnant women recommendations include: 1) postponing travel to areas where Zika virus is circulating among mosquitoes, 2) adopting precautions to avoid mosquito bites if travel is necessary, 3) men who travel to endemic areas should abstain from sexual activity with a pregnant partner, or use condoms, for the duration of the pregnancy.


“With no vaccine or antiviral drug currently available to prevent infection or protect a developing fetus, it is imperative that women in any trimester of pregnancy, women who are planning to become pregnant, and their male sexual partner follow recommendations for prevention,” said DPH Commissioner Dr. Raul Pino. 


Testing of pregnant women who have travelled to Zika virus affected countries is offered by the CDC. The DPH Public Health Laboratory facilitates shipping of blood samples from patients who satisfy travel and pregnancy criteria. So far, 127 patients were approved for testing and 50 specimens were processed and sent to CDC. Results have been received for 5 patients and none have been identified with Zika virus.


“We are working with the CDC, obstetricians and physicians throughout the state to test any pregnant woman who has recently returned from countries where Zika is present, and I encourage any woman who is pregnant or planning to become pregnant and returning from one of those countries to consult with their physician to determine if testing is appropriate,” said Commissioner Pino.  “While we have not had any positive Zika tests in Connecticut, we remain vigilant in our monitoring of this situation and will continue to keep the public informed.”


According to Medical Entomologist, Dr. Philip Armstrong, at the Connecticut Agricultural Experiment Station (CAES) the mosquito species that is primarily responsible for transmission of Zika virus to people is not found in Connecticut. A closely related species is found in parts of the state, however, it is present in low numbers and unlikely to present a risk of Zika virus infection to people. The CAES conducts mosquito trapping and testing from June to October and will be looking for Zika virus.


The most common symptoms of Zika virus disease are fever, rash, joint pain, and conjunctivitis. The illness is usually mild with symptoms lasting from several days to a week. Infection is thought to provide lifelong immunity. Severe disease requiring hospitalization is uncommon. Deaths are rare.


Travelers can protect themselves from this disease by taking steps to prevent mosquito bites. When traveling to countries where Zika virus (see map) or other viruses spread by mosquitoes have been reported, use insect repellent, wear long sleeves and pants, and stay in places with air conditioning or that use window and door screens.


For more information, please visit