This is according to a study that was recently carried out by London’s Guy’s and St. Thomas’ National Health Service Foundation Trust. The researchers studied the immune response in patients with the disease and found that the antibodies they developed decreased within a few weeks after the onset of symptoms. This means that people could well become reinfected after recovering from the illness.
According to the study, 23 days after the symptoms first appeared in patients, 60 percent experienced a potent antibody response; 65 days later, just 16.7 percent had this response. Antibodies are the proteins your body makes to fight off an infection. If there is any silver lining here, it’s the fact that those who had a more severe infection enjoyed an antibody response that was stronger and lasted longer.
The study looked at 59 patients who had tested positive for the disease, the majority of whom were men. Researchers collected sequential serum samples from the patients from one day to 94 days after their symptoms first appeared. They also looked at 31 healthcare workers who volunteered to undergo regular antibody tests.
The researchers noted that the antibody response to COVID-19 that they found was similar to that seen in other types of human coronaviruses, such seasonal coronaviruses linked to the common cold and SARS. In these viruses, a person’s antibody response tends to fade for a period of time that can be as little as 12 weeks or as long as 34 months after infection.
This study isn’t just bad news for those who have suffered from the disease and are hoping to avoid a repeat; it also indicates that coming up with a vaccine could be complicated, if not impossible. Even those with severe infections who enjoyed longer antibody responses still saw those effects fading within just a few months. That could mean, at the very least, that if a vaccine is developed, it will need to be administered frequently.
Dr. Mala Maini, a virus expert from University College London, told CNN that the study “suggests vaccines will need to be better at inducing high levels of longer-lasting antibodies than the natural infection or that doses may need to be repeated to maintain immunity.”
The U.K. study is just the latest evidence that getting infected with COVID-19 doesn’t mean people can let their guard down. A study from Spain found that just five percent of the population there had coronavirus antibodies despite experiencing a significant outbreak this spring. Moreover, their immunity to the disease faded after just a few weeks. This means that 95 percent of the country’s population is still susceptible to the virus.
The study, which took place from April to June, encompassed more than 61,000 participants, making it the largest study of its kind to date in Europe.
The study also concluded that the antibodies in Spain’s population were not sufficient to provide herd immunity, which occurs when a population is allowed a certain amount of exposure to the virus to build up immunity among the general population.
Meanwhile, a study out of China that compared the antibody responses of 37 symptomatic patients with 37 asymptomatic people found that those who did not have symptoms experienced a weaker antibody response than those who did have symptoms.
Many people have already expressed concerns about the potential side effects of a rushed COVID-19 vaccine, but that may be a moot point if the vaccine is incapable of providing people with immunity to the disease in the first place.
Sources for this article include: