A vaccine for Zika virus just might be on its way

What’s the deadliest creature on earth? Do sharks, crocodiles or snakes come to mind? Well, deaths from those creatures pale in comparison to mosquitos.

Globally, mosquitos kill more than 700,000 people a year. Researchers are now testing a vaccine that will protect people against one of those mosquito-borne diseases, the Zika virus.

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, an infectious disease specialist at St. Louis University. "They’re nasty pests.”

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 [was noticed]," George said. "There’s not enough brain tissue to hold it up.”

An effective vaccine could prevent that. George is testing one, a two-dose shot that contains an inactivated form of the virus. In the study, more than 90 percent of volunteers showed an immune response to Zika.

“Pregnancy is usually a wonderful thing," George said. "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.”

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,” Rachael said.

She said getting the vaccine was easy.

“It’s really no different than getting a flu shot,” she said.

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," George said. "We just don’t know when or where.”

In the 2016 outbreak, there were more than 5.000 Zika cases in the U.S. Most were among people returning from affected countries, but more than 200 cases came from mosquitos in Florida and Texas.

This year, more than a dozen cases have already been reported in the U.S.

It’s important to note that the virus can be transmitted by sexual contact, too, not just from mosquitos.

RESEARCH SUMMARY

TOPIC: VACCINE FOR ZIKA VIRUS

REPORT: MB #4421

BACKGROUND: The rise in the spread of Zika virus has been accompanied by a rise in cases of microcephaly and Guillain-Barré syndrome. 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)

MICROCEPHALY: Probably the most known and feared effect of Zika is Microcephaly. It is a rare neurological condition in which an infant's head is significantly smaller than the heads of other children of the same age and sex. Microcephaly can be caused by a variety of genetic and environmental factors. Children with microcephaly often have developmental issues. Generally there's no treatment for microcephaly, but early intervention with supportive therapies, such as speech and occupational therapies, may help enhance your child's development and improve quality of life. Besides Zika, it can be passed by other infections that occur during pregnancy such as toxoplasmosis, cytomegalovirus, German measles, and chickenpox. Treatment focuses on ways to manage your child's condition. Your doctor might recommend medication for certain complications of microcephaly, such as seizures or hyperactivity.

(Source: https://www.mayoclinic.org/diseases-conditions/microcephaly/symptoms-causes/syc-20375051)

NEW RESEARCH: Sarah George, MD, from the Center for Vaccine Development at St. Louis University is searching for a vaccine for Zika. She is doing one of four different studies with inactivated Zika vaccine which was developed by the Walter Reed Army Institute of Research. The vaccine trial was sponsored by the National Institutes of Health, and she is studying how this vaccine works in terms of safety and antibody responses in about ninety healthy adults. The adults are being followed for a year after vaccination Early results showed no safety issues and it raised antibodies against Zika. Dr. George hopes someday they could give the vaccine to young girls before they ever become pregnant.

(Source: Sarah George, MD)