We have an opportunity to stop the spread of Zika virus before it advances further into Central America, the Caribbean and possibly the Gulf Coast of the United States.
When it is transmitted by mosquitoes, Zika virus typically causes fever, rash and headache. In many infected individuals, Zika will produce no symptoms at all, while in a small percentage of people it produces Guillan Barre syndrome, an autoimmune disease of the peripheral nerves that can cause more severe illness.
Recent news reports about finding Zika virus in the saliva, urine, or semen of adults is concerning but it does not mean that these bodily fluids necessarily transmit the virus person-to-person. Evidence so far suggests that almost all Zika is transmitted to adults and children through the bite of the Aedes mosquito.
The overwhelming worry about Zika is its effects when mosquitoes transmit the virus to a woman early in her pregnancy. The virus has the ability to cross the placenta and infect the unborn baby to cause devastating neurologic damage and microcephaly. A paper just out in the New England Journal of Medicine reporting on an Eastern European mother who became infected in Brazil describes the profound damage to the brain of the unborn baby in agonizing detail. If you are looking for the mysterious cause of the biblical plague that killed Egypt’s babies and demoralized Pharaoh, Zika might be a top candidate.
The rapid spread of Zika across Latin America is almost equally shocking. Through infected people and mosquitoes, the virus likely swept across the Pacific Ocean from Africa to Brazil sometime in 2014 and from there to northeastern Brazil, where it produced an epidemic of microcephaly. This part of Brazil took the hit because of its extreme poverty. Women who live in poverty are exposed daily to mosquito bites because they live in housing with inadequate screens. Their outside environments are contaminated with garbage and tires that fill with water and breed mosquito larvae.
Colombia is now being affected by Zika, and we can expect the virus to expand into impoverished parts of Central America and the Caribbean. Haiti is a sitting duck. There are more than 200,000 pregnant women in Haiti in a given year and most of them have no access to mosquito protection. Based on what we saw on Yap Island in Micronesia, where Zika infected most of the population over a short period, in the coming weeks we could be looking at 100,000 or more pregnant women with Zika in Haiti, and possibly thousands or even tens of thousands of newborns with microcephaly — in a country that is largely without a government health system.
We do not have to be passive to Zika’s onslaught. During the 1950s, Latin America fought back with an aggressive program of Aedes mosquito control through expanded use of insecticides and draining collections of water that breed mosquitoes. Ultimately 18 Latin American countries became free of mosquitoes, and dengue and yellow fever rates dropped significantly until dengue returned in 1981.
We can do the same and potentially prevent Haiti and other poor areas of the Caribbean and Central America from a humanitarian catastrophe. We also have to take a long and hard look at the United States Gulf Coast, especially in Texas and Florida, where the Aedes aegypti mosquito now decimating Brazil also lives. Impoverished areas of Texas and Florida are almost as vulnerable as northeastern Brazil.
The actions are clear. It is unlikely that we will have a Zika vaccine in time for this epidemic in the Western Hemisphere. Vaccine development is not a quick process and the bar for ensuring that a vaccine is safe for use in pregnant women is high and will necessitate more than usual clinical testing. Instead we need to focus our efforts on mosquito control so that everything should be done to lead a major campaign against the Aedes mosquito in areas where Zika is now entering. It will require a coordinated campaign involving the political leaders of the Organization of American States, the U.S. Government Department of Health and Human Services and possibly even the Vatican. It is important to include the Vatican and possibly other religious governing bodies given that Christian-majority countries (and consequently Christian mothers and their babies) are under the greatest threat.
We have proof of concept that it is possible to wipe out the Aedes mosquito, at least for a period of years to decades. That might buy us time to make the Zika vaccine. We cannot be complacent when we have a small window of opportunity to do something significant if we act now.
Peter J Hotez MD PhD is dean of the National School of Tropical Medicine at Baylor College of Medicine, Texas Children’s Hospital Endowed Chair in Tropical Pediatrics, and President of the Sabin Vaccine Institute. Thinking of submitting an op-ed to the Washington Examiner? Be sure to read our guidelines on submissions.
