Evidence has shown that human's immune system could maintain its protection mechanism against a second infection of the COVID-19 virus for as long as eight months, easing previous concern that people could lose the immunity in just a few months, Australian researchers said on Monday.
The study was the result of a collaboration among Monash University, Alfred Hospital and the Burnet Institute in Australia, led by Monash University Department of Immunology and Pathology Associate Professor Menno van Zelm.
In the study, researchers analyzed blood samples taken from 25 COVID-19 patients from Day 4 post infection to Day 242 post infection, and found all of them contained a specific memory B cell which was generated in the immune system after the first infection.
This specific cell, which can exist stably in the human body for up to eight months, remembers one of two components of the COVID-19 virus from the first infection, the spike and nucleocapsid proteins so that it will recognize the virus and trigger the regeneration of antibodies targeting COVID-19 virus when they encounter a second infection.
The results raised hope of long-lasting protection from any COVID-19 vaccines and also explained why there had been so few examples of genuine reinfection across the millions of those who tested positive for the virus globally, according to Zelm,
"These results are important because they show, definitively, that patients infected with the COVID-19 virus do in fact retain immunity against the virus and the disease," he said.
"This 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."
