New information about Zika virus has been released practically every day since Brazilian public health authorities brought global attention to the emerging disease late in 2015. The news has mostly been alarming, with reports of a possible association between Zika virus infection and microcephaly and other birth defects in newborns and Guillain-Barré Syndrome in some of those infected. WHO warns that Zika virus could spread throughout the Western Hemisphere to all countries that have the mosquito host of the virus (the exceptions being Canada and Chile). El Salvadorean public health officials have urged women there not to become pregnant for two years, and locally transmitted cases have now been identified in 23 Western Hemisphere countries.
The Center for Infectious Disease Research and Policy at the University of Minnesota has compiled recent news and resources on Zika virus here. It’s a helpful compendium of the announcements and findings released by various public health entities, including the CDC and the WHO. It also compiles journal articles published on Zika virus back to 2014.
One glimmer of good news is that experts think it is unlikely that Zika virus could be transmitted to newborns via breast milk, though cases of sexual transmission are known.
A vaccine for Zika virus infection is unlikely to be ready for widespread use soon; a search in ClinicalTrials.gov shows no vaccine candidates in trials yet. Stanley Plotkin, MD, however, told The New York Times that a vaccine should not present unusual or difficult development problems, as the virus is similar to yellow fever virus and Japanese encephalitis virus, for which there have been effective vaccines for decades. That said, it takes years, and a great deal of funding, to develop any new vaccine,
A BBC News segment features an interview with American scientist Scott Weaver, PhD, at the Institute for Human Infections and Immunity at the Galveston (Texas) National Laboratory. Though the headline is promising (“Inside a high-security laboratory developing a Zika vaccine”) it’s clear that the group is in the very early stages of research into the virus and its pathogenesis. In the piece, Nikos Vasilakis, PhD, of the Center for Biodefense and Emerging Infectious Disease (University of Texas Medical Branch at Galveston) asserts that while it might be reasonable to expect a vaccine to be ready for testing next year, the regulatory process for making the vaccine widely available would normally take many more years. We have seen, however, during the West African Ebola epidemic that Ebola virus vaccines were hastened into development and used in emergent situations in innovative trials.
Here at The College of Physicians of Philadelphia, we hope to announce an event on the subject soon, so please check back in with us.