Expect a U.S. Zika Outbreak This Summer, Says Top Health Official

Mosquito season is arriving, and so is Zika in the U.S. Alvin Baez/REUTERS

As Zika continues to spread throughout Central and South America, the Caribbean and Pacific Islands, the question on many people's minds is if—and when—the U.S. might also experience an outbreak.

On Sunday, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Disease, said Americans should prepare for local transmission of the mosquito-borne virus. Fauci and other public health officials from the National Institutes of Health (NIH) suspect dozens of people will be infected. So far, local and state health authorities have only reported travel-related cases of Zika. While the virus spreading on American soil is a scary idea to many, Fauci doesn't believe the outbreak will become widespread.

Fauci's warning comes just a few days after the U.S. Centers for Disease Control and Prevention (CDC) confirmed Zika can cause microcephaly and other birth defects in infants born to women affected by the virus in her first trimester of pregnancy. In Brazil, where the outbreak first began, more than 4,000 infants have been born with serious birth defects. It's also suspected that Zika may cause stillbirths and miscarriages, and some adults have developed Guillain-Barré syndrome and acute disseminated encephalomyelitis, both autoimmune conditions that target the central nervous system.

Fauci's comments also come less than a week after he and Dr. Anne Schuchat, principal deputy director for CDC, held a press conference urging Congress to pass legislation that would set aside approximately $1.9 billion in emergency funding to combat Zika.

"Everything we look at with this virus seems to be a bit scarier than we initially thought," Schuchat said.

The CDC has issued travel advisories on more than 40 countries and territories where local transmission has been reported; most warn pregnant women and women wishing to conceive to avoid visiting.

Other public health experts have forecasted the virus would migrate to the U.S. at some point as the weather heats up in parts of the country and mosquito season begins. A report, published in PLOS Currents Outbreaks on March 16 by the University Corporation of Atmospheric Research (UCAR), suggested factors such as heat, humidity and heavy rains in the summertime will provide an ideal climate for the Aedes aegypti mosquitoes to thrive in the States.

They concluded that cities in southern Florida and Texas are at especially high risk for local transmission of the virus. Additionally, the virus is likely to be seen on the East Coast—as far up as New York—and cities in the southern region. Cities along the eastern seaboard, such as New York City, Philadelphia and Washington, D.C., will likely be affected, though the threat is much smaller there, the report said.