The National - News
Booster vaccines may be required to combat annual spread of infections
People risk being reinfected with Covid-19 every year, according to research that suggests patients who recover from the disease may remain immune for only a matter of months.
Scientists at King’s College London analysed the immune response in more than 90 patients and healthcare workers in the UK to determine the strength of viral antibodies.
The results suggest that once a vaccine is found, boosters may be required to protect people against infection.
“People are producing a reasonable antibody response to the virus, but it’s waning over a short period of time,” the study’s lead author, Dr Katie Doores, told The Guardian.
“Infection tends to give you the best-case scenario for an antibody response, so if your infection is giving you antibody levels that wane in two to three months, the vaccine will potentially do the same thing.
“People may need boosting and one shot might not be sufficient.”
The study showed peak immunity to Covid-19 occurred about three weeks after the onset of symptoms, before a steep decline.
While researchers found the strength of naturally produced antibodies were dependent on the severity of symptoms, scientists recorded a drop in the body’s ability to fight the virus.
Only 17 per cent of cases in the study showed the same strength of antibodies at the height of their symptoms as they did three months later.
In some cases, antibodies were undetectable during the follow-up analysis.
Researchers said the findings could affect hopes of herd immunity controlling the virus and placed more emphasis on finding a vaccine and the need for boosters.
Results from early testing at the University of Oxford showed lower levels of antibodies were produced in macaques that were infected with the virus and given a trial vaccine.
While the study showed the animals were protected from serious illness, they still became infected and were able to pass on the virus.
Researchers in China, Germany, Russia, South Korea, the UK and the US are conducting clinical trials on potential Covid-19 vaccines.