After Zika vaccine breakthrough, DoD researchers to test it in humans

On the heels of a National Institute of Health announcement Wednesday that the facility is launching clinical trials on humans of a Zika vaccine, the Defense Department said Thursday its vaccine candidate has been tested in monkeys and has been proved effective.

Researchers at the Walter Reed Army Institute of Research in Silver Spring, Maryland, working with Beth Israel Deaconess Medical Center at Harvard Medical School published an article online in the journal Nature saying that with two animal studies having been completed, they are ready to proceed with their own human trials.

The researchers found that the military-developed vaccine induced antibody production in two weeks and complete protection in monkeys after a second dose four weeks later.

"Results from both the mouse and non-human primate testing are encouraging and support a decision to move forward with ... our partners to advance our vaccine candidate to human trials," said Col. Stephen Thomas, an Army infectious disease specialist.
The military trials are a third of their kind. In addition to the NIH trials, Inovio Pharmaceuticals began testing its experimental Zika vaccine July 26.

“The Army has an interest in supporting development of countermeasures against Zika," said George Ludwig, a researcher with the Army Medical Research and Material Command. “Infection diseases have traditionally been the greatest threat to solder health and readiness both in the field and in garrison.”

As of Aug. 3, 41 active-duty, reserve and National Guard members have been diagnosed with Zika, including one service member who is expecting a baby.

An additional seven family members have been diagnosed with Zika.

According to the Centers for Disease Control and Prevention, more than 1,650 cases of Zika have been diagnosed in the United States, including 433 pregnant women, and 4,750 cases have been reported in U.S. territories.

Nearly all but 15 U.S. cases were contracted outside the United States. They include 15 sexually transmitted cases and one lab-acquired case.

The NIH study kicked off Tuesday with the vaccination of the first patient. The study calls for testing 80 volunteers at the NIH Clinical Center in Bethesda, Maryland, Emory University in Atlanta and the University of Maryland Baltimore County.

Both the NIH and Inovio vaccines are DNA vaccines, which unlike traditional vaccines that use deactivated or weakend viruses, or proteins from the virus designed to prompt an immune response, use genetic material derived from the viruses’ key proteins to stimulate the immune system.

The vaccine being developed by WRAIR and Beth Israel is based on more traditional vaccine development technology.
If any of the vaccines are proved effective, they would be made available to women and teenagers of childbearing age as well as their sexual partners, National Institute of Allergy and Infectious Diseases director Dr. Anthony Fauci said Wednesday.

In more than 80 percent of patients, a Zika virus infection causes few or no symptoms. But it can cause severe birth defects, including microcephaly, a condition in which babies are born with small heads and partially developed brains, and death to affected fetuses.

The CDC this week issued a travel advisory to part of Miami, telling pregnant women they should not travel to parts of the city where Zika has been found. Since Zika can linger for 10 weeks or maybe more in blood of pregnant women, they are advising that women with Zika wait at least eight weeks before trying to get pregnant and men with Zika should wait at least six months after symptoms to consider fathering children.

A breakthrough in the development of a Zika vaccine could also lead to prevention of other viruses related to Zika, including dengue, which infects roughly 390 million people worldwide each year, according to the World Health Organization, as well as yellow fever and chikungunya.

All are transmitted by the Aedes aegypti mosquito, which lives in the tropics and can summer in the United States.




Patricia Kime covers military and veterans health care and medicine for Military Times. She can be reached at [login to see]