Bioethics Blogs

Zika Vaccine: Two Candidates Show Promise in Mice

 

Caption: Zika virus (red), isolated from a microcephaly case in Brazil. The virus is associated with cellular membranes in the center.
Credit: NIAID

Last February, the World Health Organization declared a public health emergency over concerns about very serious birth defects in Brazil and their possible link to Zika virus. But even before then, concerns about the unprecedented spread of Zika virus in Brazil and elsewhere in Latin America had prompted NIH-funded scientists to step up their efforts to combat this emerging infectious disease threat. Over the last year, research aimed at understanding the mosquito-borne virus has progressed rapidly, and we now appear to be getting closer to a Zika vaccine.

In a recent study in the journal Nature, researchers found that a single dose of either of two experimental vaccines completely protected mice against a major viral strain responsible for the Zika outbreak in Brazil [1]. Caution is certainly warranted when extrapolating these (or any other) findings from mice to people. But, taking into account the fact that researchers have already developed safe and effective human vaccines for several related viruses, the new work represents a very encouraging milestone on the road toward a much-needed Zika vaccine for humans.

The two experimental vaccines undergoing testing represent different approaches to vaccine development. One approach, developed by Dan Barouch of Beth Israel Deaconess Medical Center, Boston, and colleagues, is a DNA vaccine composed of select snippets of genetic material from a Zika strain from Brazil. The DNA included in the vaccine encodes proteins found at the viral surface that are known to induce an immune response.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.