A vaccine for COVID-19 might be on the rise as two studies offer encouraging results after trials done on monkeys show either immunity or protection against the virus. Harvard University's Beth Israel Deaconess Medical Center researchers oversaw experiments on rhesus macaque monkeys.

In one report, nine monkeys contracted with COVID-19 did not re-acquire coronavirus after they recovered. In the second report, the monkeys developed immunity against the virus after they were given experimental vaccines.

Although scientists presume that antibodies produced in response to the new coronavirus are protective, there has been little evidence to back it up.

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Coronavirus Vaccine Study 1: Immunity Achieved

In one study, researchers infected nine full-grown rhesus macaque monkeys with the novel coronavirus. After their recovery, they were yet again exposed to the virus 35 days later.

Surprisingly, all nine monkeys either had minor or no symptoms of COVID-19. Furthermore, the monkeys seemingly developed immune system responses against reinfection.

According to one of the authors of the study, Dr. Dan Barouch, the findings suggest that monkeys are capable of developing natural immunity that defends against re-exposure. Dr. Barouch is also a researcher at the Center for Virology and Vaccine Research at Beth Israel.

Several research teams have released papers, also suggesting that a vaccine against the virus would be effective in animals. The said research papers, however, have not been reviewed by other scientists.

The results of the study were published in the journal Science on May 21, Wednesday.

Study 2: Protection Against Coronavirus Obtained

In the second study, Barouch and his teammates tested 25 monkeys with six prototype vaccines while the remaining ten monkeys received a placebo.

The vaccines expressed six different patterns of the spike protein found on the virus's surface. This protein is what the pathogen uses to infect cells in the human body. This allows the immune system to recognize the spike proteins and protect the body if someone becomes infected with the coronavirus.

After six weeks, the researchers exposed all of the monkeys to SARS-CoV-2. All of the monkeys in the control group showed great extents of the virus present in their noses and lungs. On the other hand, the vaccinated monkeys exhibited having a substantial degree of protection from the infection, according to Barouch.

Moreover, monkeys that received the actual vaccines displayed high levels of antibodies to neutralize the virus within two weeks. The findings revealed that no viral levels were detected in eight of the vaccinated monkeys, while the remaining 17 had scant levels of infection.

The second study was also published in the journal Science.

Although the two studies yielded positive results in monkeys, the researchers acknowledge that they do not prove to be the same in humans. The researchers say that further studies need to be conducted to address important questions such as the length of protection of the vaccines from the coronavirus as well as optimal vaccine platforms for COVID-19 vaccines for humans.

Meanwhile, vaccine manufacturing companies like Inovio, Pfizer, and Moderna have also been giving off good news about their vaccine developments. However, experts say that vaccine development takes time, and we might not see a vaccine ready for public use until the end of twelve to 18 months.

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