POST Online Media Lite Edition



 

NEWLY REPORTED COVID-19 CASES IN LAST 24 HOURS (10.19.2021, 8:23pm CEST, WHO):   U.S. 16,894    India 13,058    Brazil 5,738    United Kingdom 48,703    Russia 34,740    Turkey 29,240    Iran 11,844    Colombia 1,299    Italy 1,594    Germany 6,771    Mexico 1,993    Poland 3,930    Philippines 6,943    Ukraine 15,579    Malaysia 5,434    Netherlands 3,389    Iraq 1,559    Thailand 9,122    Czechia 2,521    Chile 1,315    Romania 18,863    Israel 1,483    Serbia 6,461    Kazakhstan 1,396    Cuba 1,844    Vietnam 3,168    Jordan 1,715    Austria 1,797    Greece 3,147    Georgia 5,739    Guatemala 3,649    Belarus 1,956    Bulgaria 4,979    Azerbaijan 1,245    Myanmar 1,133    Slovakia 1,797    Croatia 1,741    Ireland 1,576    Venezuela 1,349    Lithuania 2,235    South Korea 1,073    Mongolia 1,303    Moldova 1,370    Armenia 1,054    Latvia 1,853    Botswana 2,195    Estonia 1,101    China 30    Singapore 2,553    New Zealand 99    Australia 2,186   

DNA-based vaccine guards against Zika in monkey study

Staff Writer |
An experimental DNA-based vaccine protected monkeys from infection with the birth defects-causing Zika virus, and it has proceeded to human safety trials, researchers report.

Article continues below






"The vaccine universally elicited antibodies from all primates, but for the animals that got a full dose of vaccine, 17 of 18 were protected from infection," said study co-author Ted Pierson. He is chief of the Viral Pathogenesis Section at the U.S. National Institute of Allergy and Infectious Diseases.

Based on these findings, researchers have begun clinical safety trials in healthy human beings, Pierson said. These trials will show whether the vaccine is safe in humans, and whether it prompts an immune system response as it did in monkeys.

"When a vaccine is effective in a lower primate species, it is a good signal that it will be effective in humans," said Dr. Amesh Adalja, a senior associate at the University of Pittsburgh's UPMC Center for Health Security in Baltimore. "The NIH vaccine candidates have cleared an important hurdle, and we are awaiting results from phase 1 human studies."

This potential vaccine contains a piece of DNA created synthetically in the laboratory from the Zika virus, Pierson said.

When introduced into the body, the DNA causes small virus-like particles to be secreted from cells, Pierson explained. These particles are not full-fledged Zika, but are similar enough to the virus that the immune system might produce an antibody response that will also protect against Zika.

"This kind of vaccine, which we call a DNA vaccine, there's precedent for this," Pierson said, noting that similar technology was used years ago to create a candidate vaccine for West Nile virus.

To test the potential effectiveness of the Zika vaccine, researchers provided a single dose to six rhesus monkeys and two shots to 18 monkeys.

None of the monkeys that received a single dose was protected from Zika infection, but the vaccine did appear to create an antibody response, the researchers found. Their blood contained less Zika virus than animals who did not receive the vaccine.

The two-dose vaccine series protected 17 out of the 18 monkeys against exposure to Zika, and provided researchers with an idea of how much antibody response is needed to protect against infection.


What to read next

Eye problems may be tied to Zika, lab study suggests
Cases of Zika-linked birth defects dropped in Brazil
12,000 pregnant women with Zika - no microcephaly