The mystery of why some people dont catch COVID

The unscathed — The mystery of why some people dont catch COVID Scientists think they might hold the key to helping protect us all.

Grace Browne, wired.com – Sep 13, 2022 3:31 pm UTC Enlarged3sign via Getty Images reader comments 11 with 11 posters participating Share this story Share on Facebook Share on Twitter Share on Reddit

We all know a COVID virgin, or Novid, someone who has defied all logic in dodging the coronavirus. But beyond judicious caution, sheer luck, or a lack of friends, could the secret to these peoples immunity be found nestled in their genes? And could it hold the key to fighting the virus?

In the early days of the pandemic, a small, tight-knit community of scientists from around the world set up an international consortium, called the COVID Human Genetic Effort, whose goal was to search for a genetic explanation as to why some people were becoming severely sick with COVID while others got off with a mild case of the sniffles.

After a while, the group noticed that some people werent getting infected at alldespite repeated and intense exposures. The most intriguing cases were the partners of people who became really ill and ended up in intensive care. We learned about a few spouses of those people thatdespite taking care of their husband or wife, without having access to face masksapparently did not contract infection, says Andrs Spaan, a clinical microbiologist at Rockefeller University in New York.

Spaan was tasked with setting up an arm of the project to investigate these seemingly immune individuals. But they had to find a good number of them first. So the team put out a paper in Nature Immunology in which they outlined their endeavor, with a discreet final line mentioning that subjects from all over the world are welcome. Advertisement

The response, Spaan says, was overwhelming. We literally received thousands of emails, he says. The sheer volume rushing to sign up forced them to set up a multilingual online screening survey. So far, theyve had about 15,000 applications from all over the world.

The theory that these people might have preexisting immunity is supported by historical examples. There are genetic mutations that confer natural immunity to HIV, norovirus, and a parasite that causes recurring malaria. Why would COVID be any different, the team rationalized? Yet, in the long history of immunology, the concept of inborn resistance against infection is a fairly new and esoteric one. Only a few scientists even take an interest. Its such a niche field, that even within the medical and research fields, its a bit pooh-poohed on, says Donald Vinh, an associate professor in the Department of Medicine at McGill University in Canada. Geneticists dont recognize it as proper genetics, nor immunologists as proper immunology, he says. This is despite there being a clear therapeutic goal. If you can figure out why somebody cannot get infected, well, then you can figure out how to prevent people from getting infected, says Vinh.

But finding immune people is an increasingly tricky task. While many have volunteered, only a small minority fit the narrow criteria of probably having encountered the virus yet having no antibodies against it (which would indicate an infection). The most promising candidates are those who have defied all logic in not catching COVID despite being at high risk: health care workers constantly exposed to COVID-positive patients, or those who lived withor even better, shared a bed withpeople confirmed to be infected. Advertisement

By the time the team started looking for suitable people, they were working against mass vaccination programs, too. On the one hand, a lot of people were getting vaccinated, which is great, dont get me wrong, says Vinh. But those are not the people we want. On the other hand, seeking out the unvaccinated does invite a bit of a fringe population. Of the thousands that flooded in after the call, about 800 to 1,000 recruits fit that tight bill.

Then the highly infectious omicron variant arrived. Omicron has really ruined this project, I have to be honest with you, says Vinh. It dramatically reduced their pool of candidates. But Spaan views omicrons desecration in a more positive light: that some recruits survived the omicron waves really lends support to the existence of innate resistance.

Across the Atlantic, in Dublin, Ireland, another member of the groupCliona OFarrelly, ??a professor of comparative immunology at Trinity College Dublinset about recruiting health care workers at a hospital in Dublin. Of the cohort she managed to assemble, omicron did throw a wrench in the workshalf of the people whose DNA they had sent off to be sequenced ended up getting infected with the variant, obviating their presumed resistance. To spread awareness of their research and find more suitable people, OFarrelly went on the radio and expanded the call to the rest of the country. Again, enthusiasm abounded: More than 16,000 people came forward who claimed to have defied infection. Were now trying to deal with all of that, she says. Im hoping that well have one or two hundred from those, which will be unbelievably valuable. Page: 1 2 Next → reader comments 11 with 11 posters participating Share this story Share on Facebook Share on Twitter Share on Reddit Advertisement

You must login or create an account to comment. Channel Ars Technica ← Previous story Related Stories Today on Ars

Related posts