If you are one of the millions of Americans who have had Covid-19, you may be wondering how long you will have immunity to the coronavirus. Earlier in the pandemic, most people assumed that being infected with the virus had at least one downside: that you would be protected from future encounters with the virus. But when the latest wave hits Western part of the country and the virus shows no sign of remission, reinfection seems to have become common. Now, many people are reporting a second or even third infection with newer variants.
Experts have warned that exposure to coronavirus – through vaccination or infection – does not mean that you are completely protected from future infections. Instead, the coronavirus is evolving to behave like its close cousins, causing the common cold and infecting people many times over their lifetime.
“I have thought, almost since the beginning of this pandemic, that Covid-19 will eventually become an inevitable infection that everyone gets over and over again, because that’s just how a virus New airways are formed in the population”, Dr. Amesh Adalja, an infectious disease specialist at Johns Hopkins University.
However, the coronavirus has yet to fit into clear seasonal patterns like other common cold viruses. It can also cause debilitating symptoms that last for months or years in some people and has claimed the lives of millions of others. So what can you do to protect yourself, not only from infection but also re-infection? We asked the experts for answers to common questions.
How long will my immunity last after the Covid injection?
Before Omicron, reinfection was very rare. A team of scientists, led by Laith Abu-Raddad at Weill Cornell Medicine-Qatar, estimate that a Delta bout or an earlier strain of coronavirus is about 90% effective in preventing reinfection in both vaccinated and unvaccinated individuals. “But Omicron really changed that calculus,” said Dr. Abu-Raddad, an infectious disease epidemiologist.
After Omicron emerged, previous infections provided only about 50% protection against reinfection, Dr. Abu-Raddad’s study found. The coronavirus has had so many mutations in its mutated protein that newer versions have become more transmissible and more able to evade immunity. That means you can catch an Omicron version after recovering from an older, non-Omicron version. You may even get sick with one of the newer Omicron subspecies after passing another version of it.
Other factors also increase your chances of being reinfected, starting with how long you’ve had Covid. Immune defense tends to weaken after infection. A study published in October 2021 estimated that reinfection can occur as soon as 3 months after signing contract with Covid-19. While these findings are based on the coronavirus genome and take into account the expected decline in antibodies that can fight the virus, the study does not take into account novel variants such as Omicron that are radically different from those that can fight the virus. older body. Because of how different Omicron is, your protection may wear off sooner. In one The study was published in February Danish scientists have found that some people are re-infected with the Omicron BA.2 subline as soon as 20 days after they were initially infected with Omicron BA.1.
Dr Abu-Raddad said: “Since the virus is infecting more people now, your chances of being exposed and re-infected are also higher. And while it’s unclear whether some people are more susceptible to being reinfected with Covid-19, researchers are starting to find some clues. Dr Abu-Raddad said that people who are older or immunocompromised may produce very little or very few poor-quality antibodies, making them more susceptible to re-infection. And early research shows that a small group of people have a crippling genetic defect an important immune molecule called type I interferon, putting them at higher risk of severe Covid symptoms. Further studies may reveal that such differences also play a role in reinfection.
For now, you should treat any new symptoms, including fever, sore throat, runny nose, or change in taste or smell, as a potential case of Covid, and get tested to confirm you positive again or not.
Will subsequent infections be more or less severe?
The good news is that your body can call on immune cells, such as T cells and B cells, to prevent reinfection if the virus overcomes your initial antibody protection. T cells and B cells can take a few days to become activated and start working, but they tend to remember how to fight viruses based on previous encounters.
“Your immune system has all sorts of weapons to try and stop the virus even if it gets through the front door,” said Shane Crotty, a virologist at La Jolla Institute of Immunology in California.
Many of these immune cells build up their defenses over and over, says Dr. That means people who get the vaccine and booster are especially well equipped to get rid of it with the coronavirus. Likewise, people who have been infected before can keep the virus from replicating at high levels if they are re-infected. And most people who have logged encounters with both vaccines and coronavirus build hybrid immunity that may provide the best protection.
As a result, a second or third infection may be shorter and less severe.
Dr. Abu-Raddad, who has been tracking re-infections among large groups of people in Qatar, has begun to see this. Promising patterns in patient records: Of the more than 1,300 reinfection cases his team identified between the beginning of the pandemic and May 2021, none resulted in ICU admission and none died.
But just because reinfections are less severe, doesn’t mean they aren’t so terrible. You may still have fever and body aches, brain fog, and other symptoms. And there’s no way to know if your symptoms will persist and become Covid for long, Dr. Adalja said.
It’s possible that each Covid infection forces you into a game of Russian roulette, although some researchers theorize that the risk is highest right after your first infection. One of the Risk factors for prolonged Covid “There’s a high viral load in your system early on in the infection, and you’re likely to have such a high viral load the first time you’re infected,” said Dr. Abu-Raddad. . During subsequent infections, your body is better prepared to fight off the coronavirus, so you can keep the virus low until it’s completely cleared, he said.
What can you do to reduce your risk of reinfection?
Many of the tools and behaviors that help protect against infection can still help you avoid reinfection, says Dr. Abu-Raddad. “There is no magic solution against Covid re-infection.”
For example, vaccination and health promotion is a good idea even after you’ve had Covid. You only need to wait a few weeks after an infection to get vaccinated. The vaccines will boost your antibody levels, and research shows that they are effective in preventing serious outcomes if you get sick again. Dr Crotty said: “Scientific confidence in vaccine-induced immunity is much higher than immunity from infection.
Additional measures, such as covering indoors and in crowded spaces, social distancing, and improved ventilation where possible, can provide another layer of protection. But since most people and communities have largely abandoned these protections, it’s up to individuals to decide when to take additional precautions based on their Covid risk and how much they want to. avoid.
“If you had an infection last week, you probably don’t need to wear a mask,” says Dr. Adalja. “But when about a month has passed since you’ve had the infection and new variants have started circulating in the US, that might make sense for people at high risk. People who are trying to avoid getting Covid because they are going on an excursion or because they need a negative PCR test for some other reason can consider taking precautions. Vivid protections aren’t necessarily one-size-fits-all. ”
