Researchers worldwide are steadily progressing in their battle against the Zika virus, with two experimental vaccines developed by the US National Institutes of Health (NIH) reported to be safe and protective of monkeys against the infection.

The first experimental DNA vaccine known as VRC 5288 has already been tested for its safety and efficacy in human volunteers. The second vaccine, VRC 5283, has yet to been scheduled for a Phase 1 clinical trial.

The researchers have trialled the two different experimental vaccines on rhesus macaques using different doses, and found that two doses were “highly effective” at protecting the monkeys against infection despite exposure to a high dose of Zika virus.

Vaccine has successfully created desired immune response


In August, the NIH began clinical trials of the candidate vaccine in humans to evaluate the level of safety and ability of the DNA-vaccine to successfully generate a desired immune response in participants.

The 80 volunteers aged 18 to 35 were separated into three groups receiving the same dose of the vaccine, but at different intervals over a 20-week period. According to the National Institute of Allergy and Infectious Diseases (NIAID), DNA-based vaccines cannot cause infection of the disease to individuals, as the vaccine does not contain contagious material.

NIAID Director Anthony Fauci said that the institution is pleased to be able to proceed with initiation of the study in people, adding that results of the vaccine in trials with animals have been promising. “Although it will take some time before a vaccine against Zika is commercially available, the launch of this study is an important step forward,” he said.

NIAID: Vaccinating young women is the ultimate goal


Although infections often cause no symptoms, the Zika virus, which is mainly transmitted by the Aedes mosquito, poses menacing risks of congenital neurological defects in babies born to mothers who were infected during pregnancy.

The outbreak of the virus in North and South America and its dire consequences has caused scientists from around the world to respond with efforts to develop an effective vaccine against Zika.

Vaccinating girls before they reach puberty in areas with high prevalence of Zika is the ultimate goal, stressed Fauci.

Virginia Bliss is one of the brave volunteers participating in the trial that evaluates the safety of the experimental vaccine. She received her injection in August of this year.

“I really believe in medical research,” said the 33-year old, who has volunteered to test vaccines for other diseases including yellow fever and Ebola over the past eight years.

“What people don’t realise is that the vaccines they are using on humans have already been through so many rounds of animal testing, by the time it gets to humans, it’s been pretty well vetted,” she explained.

Additionally, another experimental vaccine that was jointly developed by Butantan Institute in Brazil and researchers from the United States will also being trials in humans in the next two months. Director of Butantan Institute, Jogre Kalil, said that the “revolutionary technology” was also safe even for pregnant women.

While the final approval of the vaccination will depend on the trials’ rates of success, various experts have projected it will be years before a full vaccine is developed to prevent infection from Zika. MIMS

Sources:
http://www.channelnewsasia.com/news/world/two-experimental-zika-vaccines-show-promise-in-monkey-studies/3149190.html
http://edition.cnn.com/2016/09/22/health/zika-vaccine-trial-soldier/
https://www.nih.gov/news-events/news-releases/nih-begins-testing-investigational-zika-vaccine-humans
http://www.nst.com.my/news/2016/09/175307/brazil-begin-zika-vaccine-trials-humans

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