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Mosquito-Borne Outbreaks Need Systemic Response, Senate Told

WASHINGTON – An official with the Centers for Disease Control and Prevention told lawmakers that the Zika virus outbreak poses a threat to the United States and the rest of the Americas and that “we must act swiftly to stop the spread.”

In testimony before the Senate Health, Education, Labor and Pensions Committee , Dr. Anne Schuchat, the principal deputy director of the Atlanta-based health agency, said researchers are making advances in addressing the problem but the work will require additional funding.

The Obama administration has requested about $1.9 billion in emergency funding to respond to the Zika outbreak, including $828 million for CDC.

The Zika virus, borne by Aedes mosquitoes, is related to dengue fever, yellow fever, Japanese encephalitis and the West Nile virus and is named after the Zika Forest of Uganda where it was first isolated. Usually treated with rest – there are no drugs or vaccines to halt the spread — there is evidence that Zika can cause abnormal brain development in babies when pregnant women are infected. Miscarriages or microcephaly — a malady that may cause reduced head sizes in newborns and impaired intellectual development – may result.

“Nature is a formidable adversary and Zika is our newest threat, particularly to pregnant women,” Schuchat said.

Medical researchers are learning more about the disease every day, Schuchat said, but “there are many things we do not know yet about Zika. These include our understanding of the spectrum of effects of Zika infection during pregnancy, the risk the virus may play in microcephaly, Guillain-Barré syndrome and other possible complications, the duration of Zika infectivity in semen, and determining what other factors may play a part in the consequences associated with the virus.”

In addition to the research, the CDC is working to accelerate mosquito control strategies, improve testing and assure preparedness for rapid detection, control and prevention within the U.S.

“The emergence and reemergence of health threats, including those spread by mosquitoes and other vectors, is not a unique event but something we expect to continue to see in the future,” Schuchat said. “These outbreaks cannot be expected to occur in isolation of one another. The Commonwealth of Puerto Rico and Hawaii were already responding to outbreaks of dengue when Zika virus arose as an urgent health threat. We need to address the threat of mosquito-borne diseases systematically, rather than episodically.”

Schuchat told the panel that the CDC is basing its preparedness and response strategies on past experience dealing with similar viruses.

“We have to be prepared for different scenarios,” Schuchat said. “Most of what we think will happen is based on what we have seen with dengue and chikungunya, which are endemic in much of Latin America, but they are not endemic in the continental United States. So the trajectory we think we will see is based on what we have seen with them.”

In addition to underwriting the development of vaccines, diagnostics and improved scientific understanding of the disease, the extra CDC funding sought by the Obama administration, Schuchat said, may be used to help health departments expand their capability to manage cases of local Zika virus transmission and implement community education and prevention programs to reduce human-mosquito contact. Resources will also be used to implement mosquito control strategies, including mosquito surveillance.

“Current mosquito surveillance capacity is uneven across the country, which makes our knowledge about the locations of the two mosquito vectors that transmit Zika virus potentially incomplete,” she said. “To effectively track the spread of the outbreak, it is critical that states and territories receive specimens and test for Zika virus to diagnose and report travel-related and locally acquired cases of Zika.”

CDC also intends to expand its efforts to assist public-health labs to test for Zika and to provide guidance on how to interpret test results.

Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, told committee members that his agency is “well-positioned to rapidly respond to infectious disease threats as they emerge.”

“These emerging and re-emerging disease threats, whether man-made or naturally occurring, are perpetual challenges, in part due to the capacity of microbial pathogens to evolve and rapidly adapt to new ecological niches,” he said. “To address the challenges posed by emerging infectious diseases, NIAID employs both targeted, disease-specific research as well as broad-spectrum approaches. NIAID maximizes its efforts by prioritizing the development of drugs effective against multiple bacteria or viruses, and platform technologies to facilitate rapid development of vaccines and diagnostics applicable to multiple infections.”

There was general agreement among committee members that addressing the Zika spread requires additional funding but questions remain over where the money should come from. Republicans want the Obama administration to initially utilize about $2.7 billion in unspent monies that were intended to address the recent Ebola scare.

Sen. Lamar Alexander (R-Tenn.), the committee chairman, acknowledged that the Zika problem “has the attention of millions of Americans.” He said some of the issues dealing with vaccines and countermeasures likely will become part of a bipartisan legislative effort dealing with medical innovations that he expects to be completed the first week of April.

Regardless, Alexander said, agreement has not been reached on a funding package related to Zika.

“I think we can get there when we go to the floor,” he said.

Sen Elizabeth Warren (D-Mass.) said Congress should take a long-range approach to the problem of infectious diseases.

“Each time a new disease threat appears, Congress gets very interested, and it holds hearings like this,” Warren said. “But Congress doesn’t show the same interest in taking steps before these crises occur to make sure that our country is actually prepared when disasters strike. The most effective work for keeping Americans safe doesn’t happen when the cameras are rolling and the world is focused on the latest outbreak. The real work happens every day and that work requires real money. It requires new mandatory funding for the NIH.”

Until then, Warren said, “our response to the latest crisis will always be too little, too late.”