The World Health Organization (WHO) confirmed that new data suggest individuals who were once infected with COVID-19 can be susceptible to secondary infections as antibodies die off.
“We have seen the number of people infected continue to grow, but we’re also seeing data emerge that protection may not be lifelong, and therefore we may see reinfections begin to occur,” Mike Ryan, executive director of the WHO’s health emergencies program, said per CNBC. “So the question is: What are the levels of protection in society?”
Researchers at the WHO are now working to determine how long antibodies in response to COVID-19 last in the human system.
Previous studies have suggested that antibodies produced in reaction to a COVID-19 viral particle can last up to five months. This would imply a longer time frame of potential immunity following a COVID-19 infection.
“What we understand is 90 to 100% of people who are infected with the coronavirus do develop an antibody response whether you have mild infection, asymptomatic infection all the way to severe infection,” Maria Van Kerkhove, head of the WHO’s emerging diseases and zoonosis unit, said.
Another study conducted by Oxford University Hospitals reportedly found that individuals who contracted the virus are “highly unlikely” to contract the virus again.
For those who did experience a second infection, symptomatic infections were more frequently observed among patients who did not have antibodies.
“In some people, it may wane after a few months but we do get a good indication that natural infection immune response is lasting for some months,” Van Kerkhove added. “We’re about a year into this pandemic and so we still have a lot to learn.”