ST. LOUIS, Missouri – Summer is just around the corner, a time for playgrounds, beaches, and mosquitos.
"There's a lot of mosquitos out there and they carry a lot of diseases," said Dr. Sarah George, St. Louis University's Infectious Disease Specialist. "They're nasty pests."
Dr. Sarah George is one of several doctors chasing a vaccine for the Zika virus. Two years ago, an outbreak caused severe birth defects in thousands of babies across Central and South America.
"Something called microcephaly where the brain never develops properly, and the skull actually collapses," explains Dr. George. "There's not enough brain tissue to hold it up."
BACKGROUND: First identified in Uganda in 1947 in monkeys, Zika was later identified in humans in 1952. The first large outbreak of disease caused by Zika infection was reported from the Island of Yap in 2007. There are currently several countries experiencing Zika virus outbreaks. In 2008, A US scientist conducting field work in Senegal fell ill with a Zika infection upon his return home to Colorado and infected his wife in what is probably the first documented case of sexual transmission. In 2015, there were 62 symptomatic Zika virus disease cases reported travelers returning from affected areas and 9 cases acquired through presumed local mosquito-borne transmission. (Source: http://www.who.int/bulletin/online_first/16-171082/en/ & https://www.cdc.gov/zika/reporting/2015-case-counts.html)
An effective vaccine could prevent that.
Dr. George is testing one: a two-dose shot that contains an inactivated form of the virus. In the study, more than 90% of volunteers showed an immune response to Zika.
"Pregnancy is usually a wonderful thing," said Dr. George. "Nobody wants to be told, 'I'm sorry, there's something seriously wrong with your baby'. Everyone wants to be protected against that and, if a vaccine can do that, that's wonderful."
Around the world, mosquitos kill more than 700,000 people a year.
Rachael Bradshaw, a prenatal genetic counselor who works with families at risk for having babies with birth defects, did not hesitate to volunteer for the study.
"It seemed like something I could do to help out, if we could find a way to protect babies in the future."
She says getting the vaccine was easy.
"It's really no different than getting a flu shot."
While Zika cases have dropped dramatically since that first outbreak, a vaccine could keep pregnant women and babies safe against future threats.
"We will have another Zika outbreak," predicted Dr. George. "We just don't know when or where."