Immunity from the deadly Ebola virus could last years after the infection, the world’s longest study of survivors by British and Guinean scientists has concluded, in findings that could have implications for coronavirus disease (COVID-19) immunity research.
The study assessed immune response in thousands of Ebola survivors from the outbreak in West Africa between 2013 and 2016.
A separate study by King’s College London found that COVID-19 antibodies may, in some cases, last only two months, leading to concerns that immunity to the virus could be shortlived, and survivors vulnerable to rapid reinfection.
The Guinean and British scientists, working from their base in Guinea, found that some Ebola survivors showed no antibodies three months after infection, despite their bodies needing to mount a strong response to fight the virus.
The scientists discovered that, without antibodies, many ebola survivors had the capacity to fight off reinfection with backup “killer” T cells and B cells.
T cells are a type of white blood cell that triggers the body’s immune response. B cells memorize the body’s attack plan against specific pathogens, and rapidly secrete antibodies when reactivated, according to the study’s findings, published in the Lancet Infectious Diseases journal.
The tests currently being used on COVID-19 survivors only measure antibodies, not T and B cells.
The report’s lead author, Miles Carroll, deputy director of the national infection service at Public Health England, said: “Just because antibodies cannot be detected, does not necessarily mean that someone has not acquired immunity from their infection.”