Monkeys develop immunity with vaccine after Covid-19 infection, studies show

  • Monkeys develop immunity with vaccine after Covid-19 infection, studies show

Monkeys develop immunity with vaccine after Covid-19 infection, studies show

The problem was more common among subjects at the older end of the age range, among 45 to 60 year olds - a finding that raises questions about how well the vaccine would work in one of the demographic groups that most needs protection from this infection, older adults.

The Beijing Institute of Biotechnology's vaccine is just one of dozens being studied around the world as public health authorities desperately search for a cure for the pandemic, which has already killed more than 94,000 people in the USA alone.

"The findings suggest that they do develop natural immunity that protects against re-exposure."

The U.S. Centers for Disease Control and Prevention has more on the new coronavirus.

In that research, nine adult macaques were infected with the virus, but then cleared it from their bodies when they were re-exposed to it 35 days later. The monkeys did not have a happy time of it, developing pneumonia and inflammation in various organs, but none suffered respiratory failure and all recovered more quickly than most humans with serious cases of Covid-19.

The vaccine is what's known as a viral vector vaccine; it uses a live but weakened human cold virus, adenovirus 5, onto which genetic material of the SARS-CoV-2 coronavirus has been fused.

New studies show monkeys infected with COVID-19 develop immunity, a positive sign for vaccines

Afterwards, they were again exposed to the virus but they did not get sick.

The authors wrote that "macaques had high viral loads in the upper and lower respiratory tract, humoral and cellular immune responses, and pathologic evidence of viral pneumonia". But about half of the volunteers - people who already had immunity to the virus used in the vaccine - did not respond as well.

Vaccinated animals developed humoral and cellular immune responses, including neutralizing antibody titers comparable to those found in convalescent humans and macaques infected with SARS-CoV-2. Eight of the vaccinated animals produced no detectable viral RNA of their own, and the rest much less than the controls. Other vaccines were associated with lower virus detection in the lungs, but not in nasal swabs.

"However. the ability to trigger these immune responses does not necessarily indicate that the vaccine will protect humans from COVID-19. we are still a long way from this vaccine being available to all".

In a separate study that included numerous same researchers, titled "DNA vaccine protection against SARS-CoV-2 in rhesus macaques", the team developed a series of DNA vaccine candidates expressing different forms of the SARS-CoV-2 Spike (S) protein and evaluated them in 35 rhesus macaques (25 adult rhesus macaques with the investigational vaccines and 10 animals received a sham control).

Researchers around the world are racing to develop a vaccine against the disease that has killed almost 330,000 people, according to Johns Hopkins University data.