Good news for vaccines? Covid-19 immunity lasts for at least eight months, Australian researchers say
People who build immunity against the coronavirus virus enjoy long-term protection from the illness, researchers in Australia have concluded, suggesting that vaccines could be effective for long periods of time.
Melbourne’s Monash University announced that a team of researchers found that antibodies guard against reinfection for at least eight months.
Their paper, published in the journal Science Immunology, is the “strongest evidence” yet that coronavirus jabs could be a workable solution to the health crisis, the university said. Previous studies suggested that antibodies to Covid-19 begin disappearing within several weeks or months. However, the new Australian research shows that specific cells within the immune system, called memory B cells, “remember” infection by the virus, and trigger a protective immune response by producing antibodies if re-exposure occurs. The study examined 25 Covid-19 patients, taking 36 blood samples from them, starting four days after infection. The last samples were taken 242 days post-infection. Researchers saw that antibodies against the virus started to wane after 20 days following infection, but found that memory B cells specific to the Covid-19 virus remained stable for at least eight months.
The results are good news for the efficacy of vaccines, and also help explain why there have been so few examples of people being reinfected by the virus, said Associate Professor Menno van Zelm, from the Monash University Department of Immunology and Pathology.
his has been a black cloud hanging over the potential protection that could be provided by any COVID-19 vaccine and gives real hope that, once a vaccine or vaccines are developed, they will provide long-term protection.
Although there is a wide range of coronavirus vaccines that have shown to be effective at building immunity against the virus, it’s still unclear how long the protection lasts. However, vaccines will also have to keep up with mutations of the virus. BioNTech CEO Ugur Sahin said earlier this week that the German company would soon have a jab to counter a new strain of Covid-19 that appeared in the UK, but expressed confidence that the current vaccine developed with US firm Pfizer will still be effective for the time being. Russia’s homegrown Sputnik V vaccine is also effective against the new strain of the coronavirus, according to Kirill Dmitriev, CEO of The Russian Direct Investment Fund (RDIF), which bankrolled the jab’s development.