Those who had the original strain of COVID could be reinfected with Delta. Those who had Delta could be reinfected with Omicron. And now, this: If you’ve had COVID before, but didn’t have the BA.5 or BA.4 subvariants of Omicron, it’s likely, if not likely, that you’ll end up with either – even if you’ve had another version of Omicron before , say the experts at Fortune. In the early days of the pandemic, reinfections were reported as a rare occurrence. It is now clear that pandemics are an inevitable fact of life – especially with new, more contagious, increasingly immunogenic variants evolving regularly. Fortune reported in May that you can expect to catch COVID about once a year, based on modeling projections. At the time, the dominant variants in the US were BA.2 — or “stealth Omicron,” nicknamed for its ability to evade detection in PCR tests — and its spin-off BA.2.12.1. Just two months later, the BA.2 was banished by the stealth Omicron spin-off BA.5 along with its close sibling, the BA.4. These are believed to be the most contagious versions of COVID to date, with the ability to evade immunity from both prior infection and vaccination. It’s a whole new ball game for reinfection, experts say, Those who had the original Omicron, BA.1, were unlikely to be reinfected with BA.2 because they were pretty much the same, says Dr. Amesh Adalja, a senior researcher at the Johns Hopkins Center for Health Security. But someone who had a previous version of Omicron is “very likely” to be reinfected with BA.4 or BA.5, he says. When it comes to BA.5 or BA.4 infection after infection with another Omicron strain, two variables are likely to come into play, according to Dr. Daniel Kuritzkes, chief of the Division of Infectious Diseases at Brighman and Women’s Hospital and professor of medicine at Medicine Harvard School. These are: how different the relatively new subvariants are from the original Omicron (very different, experts say) and how long immunity lasts in a person (estimated to be four or five months, on average). “The big question is, ‘Are there people infected with [Omicron] in January, who are now infected with BA.4 and BA.5?’ The answer is yes, obviously. Western Australia’s chief health officer, Andy Robertson, told news.com.au last week that BA.4 and BA.5 do appear to have avoided vaccination immunity and previous Omicron infection, as predicted. The district is seeing an increasing number of patients who had BA.2 and are reinfected with what is “almost certainly BA.4 or BA.5” about six to eight weeks later, he said. TLDR: You might want to order some free home COVID tests from the CDC. You can do it here.
“It doesn’t feel good, but you’re less likely to die”
BA.5 likely caused about 54% of COVID infections in the US two weeks ago, according to data released last week by the US Centers for Disease Control and Prevention. Along with BA.4, it swept South Africa this spring thanks to its immune-suppressing properties. “The Omicron BA.5 subvariant is the worst version of the virus we’ve seen,” Dr. Eric Topol, professor of molecular medicine at Scripps Research and founder and director of the Scripps Research Translational Institute, wrote recently. the subvariant was well on its way to becoming mainstream in the US “It takes immune evasion, already extensive, to the next level, and, as a function of that, enhanced transmissibility,” far beyond what has been seen before, he wrote. At this point, Adalja says it’s unlikely that someone will be reinfected with BA.4 or BA.5 after being infected with them once — at least not anytime soon. The jury is still out on whether current vaccines hold up against BA.5. But since the vaccines were 15% less effective against Omicron than against the Delta variant, even with a booster, “it would not be at all surprising to me to see a further decline in protection against hospitalizations and deaths,” he recently wrote Topol. The BA.4 and BA.5 were first spotted in the US in late March, as Fortune previously reported. The variants, discovered in South Africa, quickly spread across the country in April and May, despite almost all South Africans having been vaccinated or previously had Covid by that point. The pair of variants is quickly becoming established worldwide. But their rise is often masked because, in many countries, it coincides with a decline in BA.2 infections, Topol wrote. This can lead to the appearance of a sustained wave when, in fact, there are double waves — the first from an older version of Omicron and the second from BA.4/BA.5. Alex Sigal, a professor at the Africa Health Research Institute in South Africa, told Fortune in May that the symptoms of the new subvariants are similar to typical Omicron symptoms, which include fever, loss of smell and malaise. “I haven’t seen early symptoms of respiratory distress, the main symptom associated with COVID that makes this disease so dangerous,” he said. “It doesn’t feel good, but you’re less likely to die.”
