If someone had told David O’Connor last year that he would be testifying about the dangers of Zika, he wouldn’t have believed it.
“Until recently,” he said at a Capitol Hill hearing Wednesday, “we simply didn’t view the Zika virus as a major threat to human health.”
O’Connor, a professor of pathology and laboratory medicine at the University of Madison-Wisconsin, was one of five witnesses testifying before the Senate Committee on Homeland Security and Governmental Affairs about the hazards that Zika poses and what the government should do to help prevent the spread of the virus.
The hearing followed Tuesday’s failure by the Senate to push forward a bill that would have allocated $1.1 billion to fight Zika, a result largely due to senators voting along partisan lines. No one at Wednesday’s hearing addressed the bill.
Although experts know the virus is dangerous to pregnant women – it has been linked to microcephaly, which causes abnormally small heads in infants, and other birth defects – there is much about the disease that remains unknown, O’Connor said.
“We still don’t know what we don’t know,” he said.
A vaccine for Zika is still several years in the making, but O’Connor said that because of an apparent immunity in people who had already been infected, it would be “fairly straightforward” to make one.
Sen. Ron Johnson, R-Wis., the chairman of the committee, asked O’Connor what the stumbling block was for a vaccine if it was straightforward and several years in the making.
Those studies are going to be particularly difficult to do on pregnant women. It’s going to be difficult to expose pregnant women to the risk of a vaccine. And we also have to guard against unintended consequences.
David O’Connor, professor at University of Madison-Wisconsin
The problem, O’Connor said, is the vaccine needs to be tested on people.
“Those studies are going to be particularly difficult to do on pregnant women,” he said. “It’s going to be difficult to expose pregnant women to the risk of a vaccine. And we also have to guard against unintended consequences.”
Pregnant women compose one of the groups most vulnerable to the side effects of Zika, said Anne Schuchat, principal deputy director of the Centers for Disease Control and Prevention.
“It is tricky to develop a vaccine for pregnant people,” she said, adding that a solution could be to administer the vaccine to people who are traveling to or living in areas where the risk of Zika infection is high, or to give the vaccine to girls when they’re young.
Until a vaccine is ready, prevention tips include the usual methods for mosquito-borne diseases: advising people to avoid stagnant water, which can act as a breeding ground for mosquitoes; using air conditioning or screened-in windows to prevent mosquitoes from entering homes; and applying bug repellant when necessary.
Some states are more prepared than others. For instance, states such as Florida, California and Virginia, which have higher mosquito populations – and therefore a higher susceptibility to Zika – have programs and infrastructure that coordinate mosquito control from the state level, said T. Wayne Gale, president-elect of the American Mosquito Control Association, a nonprofit public service association based in New Jersey.
But one of the concerns is that mosquitoes are beginning to develop resistance to two of the compounds used to control them.
“It is very, very expensive to get a new ingredient approved,” said H. Fisk Johnson, the CEO of S.C. Johnson and Son, a Maryland-based company that produces household products including bug spray. “It is a big hurdle to get over. It’s something that we deal with regularly.”
In addition to being spread by mosquitoes, the virus can be transmitted sexually, which experts said makes the disease more difficult to prevent. Uncertainties still exist about how long a man who is infected with Zika carries the virus.
Creating easy access to contraception is an important part of combating Zika, said Christopher Zahn, vice president of practice activities for the American College of Obstetricians and Gynecologists.
Since the outbreak began in Brazil last summer, there have been more than 260 reported cases in pregnant women in the United States, a number that experts said would only increase in the warm summer months.
“Every day we wait is another minute that there could be an infected woman,” Zahn said at the hearing.