Major Zika Outbreak Unlikely in Continental U.S.: Fauci

Stay ahead of developments in federal and state health care law, regulation and transactions with timely, expert news and analysis.

By Jeannie Baumann

Jan. 29 — A major outbreak of the Zika virus is unlikely to occur in the contiguous U.S., the head of the nation's infectious disease programs said Jan. 29.

Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, stopped short of saying an outbreak of the mosquito-borne virus—which has been spreading throughout the Americas and has been linked to a serious brain birth defect—would never occur. But he said past experience indicates the U.S. has been able to contain locally acquired cases of similar viruses.

“You never say never, and you never say always,” he said. “So what we do is we prepare for the possibility of a major outbreak. But in reality, you have to say, we believe—we don’t know, we believe—that it is unlikely that it would happen.”

At the same time, he said, the NIAID is working on developing vaccines, better diagnostic tests and better methods to limit or eradicate the mosquito that is transmitting Zika.

“You don’t just want to walk away and be very cavalier,” he said. “We’re doing everything that you would do if you were anticipating that there is going to be an outbreak.”

Fauci made his remarks during a luncheon organized by the Economic Club of Washington, a nonprofit business organization that holds forums on public policy issues. A Senate health panel announced the same day that it would hold a hearing on Zika, while another senator earlier called for emergency funding to develop a vaccine and treatment.

Dengue Fever

While there have been cases of U.S. travelers acquiring Zika abroad and bringing an infection home, the Centers for Disease Control and Prevention said there have been no reports of a Zika infection occurring within the continental U.S.

Fauci said his assessment that a major outbreak is unlikely is based on past experience with handling locally acquired cases of the dengue virus, which falls into the same class of viruses and is transmitted by the same type of mosquito. There have been small, mini outbreaks in Florida and on the Gulf Coast of Texas of dengue fever, but he said those cases have been contained with public health interventions and by controlling the mosquito population.

“We’ve had these infections lapping on our shores for years and years and years,” he said about dengue. “And although we’ve had both imported cases and some locally acquired, we’ve not seen a major outbreak.”

But Fauci said Zika overall is “fundamentally less severe” than dengue or another mosquito-borne virus called chikungunya. When asked if he would recommend traveling to Brazil—where the first reports of the outbreak emerged—he said, “If you’re going to say, ‘Don’t go to Brazil because I’m afraid of getting Zika,' then you shouldn’t go to Brazil because you’re afraid of getting dengue, which is much more serious. The issue that’s the real issue is the pregnancy issue, and that should not be taken lightly.”

In a move Fauci described as “something they don't usually do,” the CDC issued a travel advisory that pregnant women consider postponing travel to any area where Zika virus transmission occurring. The advisory is due to reports of a birth defect in the brain, along with other poor pregnancy outcomes when the mother became infected with Zika.

Senate Action

Sen. Lamar Alexander (R-Tenn.), chairman of the Senate Health, Education, Labor, and Pensions Committee, said in a Jan. 29 statement that he and HELP ranking member Patty Murray (D-Wash.) plan to hold a hearing “very soon” on how Congress can support efforts to prevent further spread of the virus and protect families from being affected.

“The spread of the Zika virus in South America and other regions, affecting so many mothers and fathers and children, is heartbreaking and its threat to the United States is of big concern,” Alexander said.

Sen. Kirsten Gillibrand (D-N.Y.) also sent a letter to Fauci Jan. 28 urging him to prioritize research on ways to combat the spread of the virus. She also called on Senate appropriators to provide the NIAID with emergency funding to support the development of screening, treatment and prevention technologies.

“The imminent threat of Zika to the United States is deeply troubling, as are reports that the development of a vaccine could take as long as ten years,” she said.

To contact the reporter on this story: Jeannie Baumann in Washington at

To contact the editor responsible for this story: Lee Barnes at

More about the Zika virus from the CDC is available at

The travel advisory is available at

The full text of Gillibrand's letter is available at

More information about Economic Club forums is available at

Request Health Care on Bloomberg Law