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How strong is your immunity against Omicron?

 

For months, scientists, public health officials, politicians and the general public have debated whether prior SARS-CoV-2 infection — touted as “natural immunity” — offers protection against COVID-19 that is comparable to vaccines.

 

The answer to that debate is complicated, but studies show the best way to protect yourself against the Omicron variant of the coronavirus is to get vaccinated and then boosted. An infection on top of that, while not desirable, offers even more protection.

 

Recent evidence suggests that “natural” COVID-19 protection depends on many factors, including when the infection happened, the variant involved, whether someone has been boosted or not, and the overall strength of their immune system.

 

“The question about natural versus vaccination immunity is an important one,” Monica Gandhi, an infectious disease specialist and professor of medicine at the University of California, San Francisco, told Yahoo News. “The CDC showed that up to the Delta surge, no doubt, natural immunity is likely as protective or more protective even than your two-dose vaccines,” she added.

 

Gandhi was referring to a study published two weeks ago in the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report. It is the same study that GOP lawmakers pointed to this week when introducing the “Natural Immunity Transparency Act,” arguing that the CDC data “demonstrated natural immunity was 3-4 times as effective in preventing COVID-19 compared with vaccination.”

 

But this claim needs more context. The CDC study analyzed COVID-19 cases in California and New York in 2021, which together only account for about 18 percent of the U.S. population. The data was collected from May 30 to Nov. 20, 2021, a period before and during the Delta wave. The study showed that prior to Delta, which became predominant in late June and July 2021, case rates were lowest for people who were vaccinated and not previously infected with COVID-19. But by early October, when Delta was dominant, the picture changed. Case rates then were substantially lower among both unvaccinated and vaccinated people with previous infections, suggesting that natural immunity during this period was superior to vaccines.

 

However, it is important to note that the CDC research was conducted during a time when vaccine-induced immunity was waning for many people and before the emergence of the highly transmissible Omicron variant. Additionally, most U.S. adults were not yet eligible to receive booster shots, which are seen as offering the best protection against Omicron.

 

In general, studies conducted pre-Omicron do support the concept that infection-induced immunity and vaccine-induced immunity are pretty similar in terms of protection. However, Gandhi said there are many reasons vaccines are preferred. Notably, vaccines are free, safe and quick, while getting COVID-19 carries substantial risks, including long COVID, hospitalization and death. “It’s just safer,” Gandhi said.

 

She also said natural immunity can vary substantially from person to person, depending on many factors like age, the overall strength of the person’s immune system, how severe the COVID case was and the variant that infected them.

 

“What happens with natural infection is that if you have a mild infection, you may not mount the strong cellular immune response that you need to fight it in the future,” Gandhi said. On the other hand, vaccines were subject to rigorous trials and found to elicit a high immune response. Most experts agree that a vaccine is a more quantifiable, predictable and reliable way to protect the population.

 

Another downside to relying on natural immunity is that Omicron has replaced Delta as the dominant variant, and Omicron is both more transmissible and more capable of evading immune protection triggered by both vaccines and previous infections.

 

Shane Crotty, a virologist and professor at La Jolla Institute for Immunology, told Yahoo News that the Omicron variant changed everything. “Omicron is looking so different from the other variants that just infection alone might not be giving you great antibodies against the other variants because it looks so different,” he said. It is still unclear how much immunity one can expect to come out of an Omicron infection, including how long that protection lasts and whether it will apply to future variants.

 

Based on the epidemiological data available, Crotty said, those who are likely to be the most protected against both infection and hospitalization at the moment are people who have had a breakthrough infection. This means, individuals who have had an infection and then a vaccine, or vice versa.

 

“Data by tons of labs shows that those people make really broad neutralizing antibodies,” the professor said. “Their antibodies recognize every possible variant and even distant viral species, but they also make really high levels of those antibodies,” he added.

 

People in this category — both infection and vaccination — have what has become to be known as “hybrid immunity” or “super immunity.” According to a CDC study, those who get fully vaccinated after recovering from COVID-19 have twice the protection of those who do not get vaccinated after their recovery.

 

Experts warn, however, this doesn’t mean people should purposefully try to infect themselves with the coronavirus to achieve greater protection against COVID-19, since there are serious health risks involved.

 

People who are boosted also have an especially high level of protection against Omicron. “It’s pretty amazing three doses of the same vaccine, which is just against the ancestral strain. Your immune system is so clever. It’s seeing that old version of the spike protein basically, and the first two times it sees it, it makes neutralizing antibodies against the ancestral strain and a couple of variants, but not Omicron, but just seeing that same vaccine the third time, and now you make neutralizing antibodies against Omicron,” Crotty explained.

 

Underscoring the value of a third dose, recent studies by the CDC have shown a booster dose of the COVID-19 vaccine significantly reduces a person’s chance of hospitalization from the Omicron variant. One of the CDC reports, which looked at 259 hospitals and 383 emergency departments from late August through early January, found that a third dose of either the Pfizer or Moderna vaccine was 90 percent effective at preventing hospitalization and 82 percent effective at preventing emergency department and urgent care visits.

 

However, despite the evidence supporting the efficacy of a third dose, many Americans have been hesitant to receive their booster shots. Gandhi says this is unfortunate because boosters could be the ticket back to normal, and those who are unboosted or unvaccinated are more vulnerable to Omicron and future variants that could emerge. “What we need to get through this time is immunity ... so even if you’ve been actually infected, I really would recommend at least one dose of a vaccine,” Gandhi said.

 

www.vox.com/coronavirus-covid19/22841229/covid-19-us-canc...

 

Covid-19 created America’s next health care crisis: The cancers we didn’t catch early

 

The pandemic dramatically disrupted cancer screenings, and thousands of lives are now at stake.

 

Steve Serrao, chief of gastroenterology at a hospital in Moreno Valley, California, just lived through the fourth wave of Covid-19 with the omicron variant sweeping across the country. Patients in respiratory distress once again filled the hospital’s beds.

 

But it is another wave, one that’s starting to trickle in but is still a long way from cresting, that Serrao worries about most. He fears that the delayed diagnoses of various cancers and other chronic, life-threatening illnesses — the result of Covid-19’s disruption to routine checkups and screenings — will be the next crisis that overwhelms the US health system.

 

“Our next surge will be advanced chronic disease,” Serrao told me over the phone. “That’s going to be the next surge of patients who overwhelm our system. I don’t think our systems are ready.”

 

The Covid-19 pandemic dealt a crushing blow to the preventive services that can catch potential health problems before they become life-threatening. Screenings for several major cancers fell significantly during 2020, according to a study published in December 2021 in the journal Cancer. Colonoscopies dropped by nearly half compared to 2019, prostate biopsies by more than 25 percent. New diagnoses declined by 13 percent to 23 percent, depending on the cancer — not because there was less cancer in the world, but because less of it was being detected. The screening backlog was still growing by the end of 2020, according to this recent study, albeit at a slower rate.

 

“I think we are absolutely in uncharted territory,” Brian Englum, a University of Maryland surgeon who co-authored the new Cancer study, told me. “There are no examples I know of where we have seen numbers change this dramatically.”

 

The fear among doctors is that the pandemic’s disruption to cancer screenings and other preventive measures won’t just be a blip, although a blip would be bad enough on its own: When cancer gets diagnosed late, it’s less likely a patient’s doctors can successfully intervene, and the patient is more likely to die. Even a four-week delay in diagnosis is associated with a 6 to 13 percent higher risk of death.

 

But they also fear that the missed screenings will lead to a more permanent disconnect between patients and the health system. Research has found that when patients lose their primary care doctor, they tend to end up in the hospital more, with more serious health problems. People who have skipped appointments or didn’t get screenings or care may be less likely to seek it in the future, and the problems could compound.

 

It may take years for the consequences to become clear. Before the pandemic, some physicians questioned if the US might be conducting too many screenings. But the country is now being forced to undergo an unintended natural experiment in less screening, one with thousands of lives at stake. The collateral damage of a pandemic that has killed more than 900,000 Americans could grow even more.

 

“We could be years into this before we know there’s a problem,” Englum said, “and we’ve already lost a lot of people.”

 

“How many of these cases are out there? Nobody knows.”

 

Serrao described one of his patients as a Hispanic man in his 40s. When he first noticed bleeding in early 2020, the patient talked to his primary care doctor, who told him it might be hemorrhoids, Serrao said. The primary care doctor acknowledged that getting a cancer screening would be impossible on short notice because the local hospitals were so strained with Covid-19. And the patient feared he might get sick if he went to a hospital.

 

Ultimately, it was 18 months before the patient sought a colonoscopy. He was diagnosed with what was, by then, advanced rectal cancer, Serrao said.

 

If the man had come in right away, Serrao said, he might have been cancer-free after a simple polyp removal. Instead, the doctor and his team are now battling cancer that has moved into other parts of the patient’s body. His outlook is much worse than it would have been if the cancer had been caught sooner.

 

“How many of these cases are out there? Nobody knows,” Serrao said.

 

Serrao’s patient had the misfortune to notice symptoms amid the biggest disruption of medical care in US history — one that hit cancer screenings particularly hard. In April 2020, as many hospitals canceled services in order to prepare for the expected surge of Covid-19 patients, the number of colonoscopies plummeted 93 percent. Then, after a brief rebound, the late 2020 winter wave stretched hospitals and forced them to limit services. By the end of the year, there had been 133,231 fewer colonoscopies performed in 2020 compared to the 2019 baseline, 62,793 fewer chest CT scans, and 49,334 fewer fecal blood tests.

 

“The drop-off in screenings has made me born again on the importance of screening,” John Marshall, chief of oncology at Georgetown University Hospital, told me. “We’re seeing more advanced diagnoses, and people presenting at a stage where they no longer can be cured.”

 

It will take months for the backlog to be cleared. Carrie Saia, the CEO of a community hospital in Holton, Kansas, told me that one of her facility’s gastroenterologists had been recruited by a larger Kansas City hospital to “scope from 7 in the morning to whenever at night, doing nothing but scopes.”

 

“They’re 1,000 people behind and backlogged right now,” Saia said. “A certain percentage out of those patients are going to have cancer growing.”

 

And working to clear that backlog begets a new backlog. Patients who are just now seeking a screening are finding it harder to get appointments. Marshall said he knew of patients who first experienced symptoms in September, were recommended for a screening by their doctor, but still couldn’t get an appointment as of December because there are so many patients in need of colonoscopies, MRIs, and other screening procedures.

 

Covid-19 led to direct rationing in overwhelmed hospitals last summer; they were unable to take patients with acute medical emergencies and couldn’t find another facility to take them. But this more subtle kind of rationing — delaying necessary services for months because the backlog has grown so large — also takes its toll, forcing doctors to make hard choices about which patients to prioritize.

 

“Everything is harder,” Marshall said. “We’ve had to make trade-off and priority decisions about who’s getting the treatment before the other person, decisions we would never have had to make.”

 

Covid-19’s disruption of US health care is likely going to deepen disparities

 

Serrao practices at the Riverside University Health System in San Bernardino County, about an hour and a half drive from downtown Los Angeles. Roughly two-thirds of his patients are Black, Hispanic, or Asian/Pacific Islander. Almost all of them have government insurance, either Medicare or Medicaid.

 

Black Americans already experience a higher incidence of and a higher mortality from colorectal cancers than white Americans. Black and Hispanic patients also tend to be diagnosed with more advanced lung cancers than their white peers, they have higher mortality from breast cancer, and they receive fewer prostate exams. At each stage, from preventive screenings to death rates, disparities already existed.

 

“They already have health disparities on a good day,” Serrao told me. “These last couple of years have put them back multiple years. The setback is quite profound.”

 

Over the course of the pandemic, Serrao’s practice struggled to make a dent in the backlog. Just as they would gain some momentum, another surge of Covid-19 would interrupt their progress.

 

Last January, the GI unit at his hospital was converted to a recovery area for patients receiving radiation therapy and other cancer treatments because overflow Covid-19 patients were in the space usually reserved for oncology recovery patients. As a result, he and his team couldn’t perform any screenings.

 

It was a necessary step — the top priority was maintaining treatment for patients already diagnosed with cancer — but it required the postponement of screenings to identify new cancer cases. The backlog got bigger.

 

“I’m almost certain that there are population pockets out there that have high disparities with cancer that will show up in the next year, two years, three years with more advanced cancers,” Serrao said, “and that’s because of the disruption in health care.”

 

The US will be living with the fallout of delayed cancer screenings for years

 

That problem may only be getting worse over time. Englum told me that one of the more troubling implications of their findings is that cancer screenings did not return to their pre-pandemic normal by the end of 2020.

 

It wasn’t a two- or three-month blip during the worst of the outbreak. By the end of the year, the drop in screenings looked more and more like a permanent setback. It’s the same problem we’re seeing with routine vaccinations: people who missed their shots and aren’t catching up even as we enter a new post-Covid normal.

 

“What our study shows is not only did we not make up for the blip, we didn’t even get back to baseline by the end of 2020,” Englum said. “We kept losing ground.”

 

The US health system struggled before the pandemic with managing people’s care in a timely fashion. It requires having an established relationship with a primary care doctor — which fewer and fewer Americans do — and then staying on schedule with recommended preventive screenings like colonoscopies and mammograms. As of 2018, according to a federal study, only 8 percent of Americans were receiving all the preventive services that are recommended for them.

 

Americans have now lived through two years when their primary care practice might have been closed, permanently or temporarily. The hospitals where they would have gotten a colonoscopy were postponing those non-emergent procedures. Some of them may have been afraid to go to the doctor or hospital, knowing that a highly transmissible virus was on the loose.

 

That only makes the challenge of getting people to stay on top of their health care harder. Doctors worry that people’s habits may be permanently changed by the pandemic — and not for the better.

 

“I am fearful that once people got out of that habit, they didn’t see an immediate problem,” Englum told me. “Then they say, ‘Well, I haven’t seen my doctor for six months or a year and nothing happened. I feel fine.’ They’re just out of the habit. They lost the routine.”

 

That means the health system is flying blind. Unless people get back in the habit of getting their recommended screenings, doctors will lose ground every year in identifying patients with serious conditions or at risk of developing them. That would limit their ability to get ahead of emerging health problems before they become chronic or even life-threatening.

 

In theory, Englum pointed out, this also could be an opportunity to learn whether the current screening guidelines are actually appropriate. If 10 years were to pass and there were no appreciable increase in cancer mortality, for example, maybe we could revise our recommendations for colonoscopies from every 10 years to every 12. The pandemic would have provided evidence such a delay doesn’t present a big risk at the population level.

 

That kind of reevaluation is happening across the health system. Health insurers are monitoring the outcomes for patients who delayed kidney treatment because of Covid-19. They are watching for any negative effects, but also for countervailing evidence that might indicate the missed care was actually unnecessary.

 

At every level, the pandemic has forced a natural experiment in what a disruption to the usual treatment plan means for patient outcomes. We are going to learn a lot, like it or not. The risk is that those lessons will come at the cost of thousands of lives.

 

Because the flip side of the optimistic scenario is that in 10 years’ time, we will see cancer mortality increasing as a result of delayed screenings.

 

“By then,” Englum said, “you’ve lost the opportunity to treat however many thousands of people.”

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