If you’re one of many tens of millions of Americans who’ve already had Covid-19, it’s possible you’ll be questioning how lengthy you’ll have immunity from the coronavirus. Earlier within the pandemic, most individuals assumed that getting contaminated had a minimum of one upside: that you’d be protected towards future encounters with the virus. But as the most recent wave heads towards the Western area of the nation and the virus exhibits no indicators of easing up, reinfections appear to have turn into widespread. Already, many individuals are reporting second and even third infections with newer variants.

Experts have warned that publicity to the coronavirus — by vaccination or an infection — doesn’t imply that you’re fully protected against future infections. Rather, the coronavirus is evolving to behave extra like its carefully associated cousins, which trigger widespread colds and infect folks repeatedly all through their lives.

“I’ve thought, almost since the beginning of this pandemic, that Covid-19 is eventually going to become an inevitable infection that everybody gets multiple times, because that’s just how a new respiratory virus gets established in the human population,” mentioned Dr. Amesh Adalja, an infectious-disease specialist at Johns Hopkins University.

However, the coronavirus doesn’t but match into clear seasonal patterns like the opposite widespread chilly viruses. It can even trigger debilitating signs that persist for months or years in some folks, and has claimed the lives of tens of millions of others. So what are you able to do to guard your self, not solely from an infection but in addition reinfection? We requested specialists for solutions to widespread questions.

Before Omicron, reinfections had been uncommon. A staff of scientists, led by Laith Abu-Raddad at Weill Cornell Medicine-Qatar, estimated {that a} bout with Delta or an earlier coronavirus pressure was roughly 90 % efficient in stopping a reinfection in each vaccinated and unvaccinated folks. “But Omicron really changed that calculus,” mentioned Dr. Abu-Raddad, an infectious illness epidemiologist.

After Omicron emerged, prior infections solely supplied about 50 % safety towards reinfection, Dr. Abu-Raddad’s examine confirmed. The coronavirus had acquired so many mutations in its spike protein that newer variations grew to become extra transmissible and higher in a position to evade immunity. That means you may catch a model of Omicron after recovering from an older, non-Omicron variant. You may even get sick with one of many newer Omicron subvariants after getting over a distinct model of it.

Other components additionally enhance your vulnerability to reinfection, beginning with how lengthy it has been because you had Covid. Immune defenses are inclined to wane after an an infection. A examine printed in October 2021 estimated that reinfection might happen as quickly as 3 months after contracting Covid-19. While these findings had been primarily based on the genome of the coronavirus and accounted for anticipated declines in antibodies that would combat off the virus, the examine didn’t account for brand new variants like Omicron that had been radically totally different from older variants. Because of how totally different Omicron is, your safety could wane even sooner. In a examine printed in February that has not but been peer-reviewed, scientists from Denmark discovered that some folks obtained reinfected with the BA.2 sublineage of Omicron as quickly as 20 days after they obtained contaminated with the unique Omicron BA.1.

Because the virus is infecting extra folks now, your probabilities of being uncovered and getting reinfected are additionally greater, Dr. Abu-Raddad mentioned. And whereas it’s unclear if some individuals are merely extra vulnerable to Covid-19 reinfection, researchers are starting to search out some clues. People who’re older or immunocompromised could make only a few or very poor high quality antibodies, leaving them extra susceptible to reinfection, Dr. Abu-Raddad mentioned. And early analysis exhibits {that a} small group of individuals have a genetic flaw that cripples a vital immune molecule known as interferon kind I, placing them at greater danger of extreme Covid signs. Further research might discover that such variations play a job in reinfection as nicely.

For now, it’s best to deal with any new signs, together with a fever, sore throat, runny nostril or change in style or scent, as a possible case of Covid, and get examined to substantiate in case you are optimistic once more.

The excellent news is that your physique can name on immune cells, like T cells and B cells, to quash a reinfection if the virus sneaks previous your preliminary antibody defenses. T cells and B cells can take just a few days to get activated and begin working, however they have a tendency to recollect easy methods to battle the virus primarily based on earlier encounters.

“Your immune system has all kinds of weapons to try and stop the virus even if it gets past the front door,” mentioned Shane Crotty, a virologist on the La Jolla Institute for Immunology in California.

Many of those immune cells construct up their protections iteratively, Dr. Crotty mentioned. That implies that people who find themselves vaccinated and boosted are particularly nicely outfitted to duke it out with the coronavirus. Similarly, individuals who have been contaminated earlier than are in a position to preserve the virus from replicating at excessive ranges in the event that they get reinfected. And most individuals who’ve logged encounters with each the vaccine and the coronavirus construct up a hybrid immunity that will supply the very best safety.

The result’s that second or third infections are prone to be shorter and fewer extreme.

Dr. Abu-Raddad, who has been monitoring reinfections amongst giant teams of individuals in Qatar, has already began seeing this promising sample in affected person information: Of greater than 1,300 reinfections that his staff recognized from the start of the pandemic to May 2021, none led to hospitalization in an I.C.U., and none had been deadly.

But simply because reinfections are much less extreme, it doesn’t imply that they aren’t horrible. You should run a fever and expertise physique aches, mind fog and different signs. And there’s no method of understanding in case your signs will linger and turn into lengthy Covid, Dr. Adalja mentioned.

It is feasible that every Covid an infection forces you right into a sport of Russian roulette, although some researchers hypothesize that the danger is highest proper after your first an infection. One of the danger components for lengthy Covid is having excessive ranges of virus in your system early in an an infection, and you might be prone to have such a excessive viral load the primary time you might be contaminated, Dr. Abu-Raddad mentioned. In subsequent infections, your physique is healthier ready to combat off the coronavirus so that you might be able to preserve the virus at low ranges till it’s fully cleared, he mentioned.

Many of the instruments and behaviors that assist defend towards an infection can nonetheless enable you keep away from reinfection, Dr. Abu-Raddad mentioned. “There is no magical solution against Covid reinfection.”

Getting vaccinated and boosted, for instance, is a good suggestion even after you’ve had Covid. You solely want to attend just a few weeks after an an infection to get a shot. The vaccines will bolster your antibody ranges, and analysis exhibits that they’re efficient in stopping extreme outcomes if you happen to get sick once more. “Scientific confidence in vaccine-induced immunity was and is much higher than infection-induced immunity,” Dr. Crotty mentioned.

Additional measures, like masking indoors and in crowded areas, social distancing and enhancing air flow the place attainable, can present one other layer of safety. But as a result of most individuals and communities have largely dropped these protections, it’s as much as people to determine when to undertake further precautions primarily based on their danger of getting Covid and the way a lot they’d wish to keep away from it.

“If you had an infection just last week, you probably don’t have to mask up,” Dr. Adalja mentioned. “But as a month or so passes from your infection and new variants start circulating in the U.S., it may make sense for high risk individuals to do that. People who are trying to avoid getting Covid because they’re going on a cruise soon or because they need a negative P.C.R. test for some other reason may consider taking precautions. Covid protections don’t have to be one-size-fits-all.”