New studies reveal that antibodies developed by recovered coronavirus patients may only last a few months. However, some scientists say it doesn't necessarily mean protection is also gone. Furthermore, they also point out that it shouldn't discourage others from developing an effective vaccine.
About ten researchers from the David Geffen School of Medicine at the University of California in Los Angeles wrote a correspondence published in the journal The New England Journal of Medicine on Tuesday, July 21, 2020.
Scientists say that even as antibodies fade, protection from COVID-19 may still remain.
According to Dr. Buddy Creech, an infectious disease specialist at Vanderbilt University, who is not involved in the work, said that infection with the coronavirus does not automatically produce lifetime immunity.
Furthermore, he added that the immune system retains memories of how to make fresh antibodies and that other parts of it could also escalate an attack.
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Short-lived Coronavirus Antibodies
Professor Danny Altmann from Imperial College London has recently warned that it is not a "safe bet" to rely on immunity to Covid-19 as a strategy for coping with the pandemic. He contests that antibodies to the virus seem "fragile" and rather short-lived.
In the correspondence, Dr. Otto Yang and his colleagues at UCLA measured more accurate antibodies in 30 patients diagnosed with COVID-19, and four housemates assumed to have the infection. The subjects' average age was 43, and most only had mild symptoms.
The researchers discovered that the antibodies they acquired had a half-life of 73 days. Moreover, this meant that half of them would be gone after the said period.
Their findings are in line with previous reports from China, also suggesting that coronavirus antibodies fade quickly. Additionally, the Califonia-based authors write that their results call for caution concerning antibody-based immunity passports, herd immunity, and vaccine durability.
Antibodies and Immunity
Antibodies are proteins that B cells produce to bind to the virus and aid in eliminating it. The first ones may be crass, but as the infection progresses, the immune system becomes trained to target its attack to make more definite antibodies.
According to Dr. Creech, other parts of the immune systems also aid in providing protection. Aside from producing antibodies, B cells also develop a sort of "memory," so they know how to combat specific diseases again.
He says they would most likely lie dormant, just waiting until they are needed again when the body gets exposed to the same pathogen. Moreover, he says other white blood cells called T cells are also better in attacking the virus the next time they encounter it.
Although it appears that antibodies might not last long, it would be crucial to determine how if and how people produce antibodies again if exposed to the coronavirus for a second time. Furthermore, Alison Criss, an immunologist at the University of Virginia, says it is vital to find out whether T cells produce a protective response.
Vaccines, on the other hand, aggravates the immune system to produce antibodies. Additionally, it might give off longer-lasting protection than natural infection. Finally, Creech says that antibodies are merely part of the story, and its short-lived nature shouldn't dishearten developers from pursuing a vaccine.