Zika in the U.S: Can We Manage the Risk?

While no local transmissions of Zika have occurred to date in the continental United States, more than 500 travel-based cases have been officially diagnosed so far and a fetus in Puerto Rico was diagnosed with Zika and microcephaly this month. Health officials believe the actual number of cases in the United States may be much higher, however, into the many thousands, as 80 percent of Zika infections present no symptoms.

Public health officials warn the virus poses an imminent threat and they may only be a few steps closer to understanding the full spectrum of risks.

On May 24, representatives from the National Institutes of Health, Centers for Disease Control and Prevention, and Google joined a conversation with NPR Global Health and Development Correspondent Jason Beaubien to give an update on how the United States is managing the disease.

While the virus is primarily transmitted by the difficult-to-control Aedes aegypti mosquito, it can also be transmitted sexually by people from males to partners of either sex. Over the summer of 2016, local outbreaks are likely to occur in the southern United States as mosquito populations multiply, said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

The Centers for Disease Control and Prevention confirmed in April that Zika can cause microcephaly and other fetal brain defects, but research into the exact effects of the virus continues. “We don’t yet know whether babies that are born looking healthy following a Zika infection will continue to develop normally,” said Rear Admiral Dr. Anne Schuchat, principal director of the Centers for Disease Control and Prevention.

Meanwhile, the earliest date for a vaccine is estimated to be late 2017.

“We have made successful vaccines against other flaviviruses... So conceptually, I don’t see any scientific roadblock to developing a vaccine for Zika,” said Dr. Fauci. “As soon as the CDC and the NIH realized that we were going to have to put a full-court press on this, we started working on a Zika vaccine.”

A lack of funding for research coupled with cutbacks in mosquito control and surveillance infrastructure is an issue, however, said Rear Admiral Schuchat. After delays and debates over dollar amounts, Congressional funding for Zika research and containment appears to be forthcoming, but in the meantime progress has been slow.

Zika remains first and foremost a concern for pregnant women and those who are vulnerable to Guillain-Barre syndrome, an immune system disorder that is not well understood. In addition, poor and marginalized groups are most at risk due to their lack of access to protective measures and information about the disease.

Former New York Congresswoman Susan Molinari, now vice president of public policy at Google, said they have recorded a surge of interest in the virus globally. “We have seen…since November a 3,000 percent increase in searches.” These trends can be predictive of the actual spread of a disease, as Google has observed with flu each year.

Many Americans are unaware of the simple steps they can take to minimize their exposure and prevent the spread of the virus, said Rear Admiral Schuchat. Social engagement and public information campaigns will therefore be an important part of the response as a vaccine is developed. Basic measures include covering exposed skin while traveling to infected areas and wearing insect repellant for three weeks upon return to the U.S. to prevent local mosquitoes from becoming infected. Men should also be cautious about engaging in sexual activity for eight weeks after returning from an affected region, said Dr. Fauci, since infections often do not present symptoms.

“The media has been responsible,” said Schuchat. “Frankly, this virus is scary enough on its own. You don’t actually have to hype this.” 

Photo Credit: A woman in the Dominican Republic participates in an outreach program by the Office of the First Lady, courtesy of the Presidency of the Dominican Republic.