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Canadians concerned over waning immunity from COVID-19 vaccines, breakthrough infections and the need for booster shots in the general public could benefit from a dose of some important context, experts say.
Antibodies, your first line of defence against COVID-19 infection, do decline — and may even be doing so as you’re reading this — but that’s not unexpected.
While one aspect of your vaccine-induced immunity to COVID-19 is technically “waning” in the weeks and months after vaccination, that’s not necessarily a bad thing — because it’s not your immune system’s only form of protection against the virus.
“I don’t even like the term,” said University of Toronto immunologist Jennifer Gommerman. “And the reason I don’t like the term is that it implies that the immune response in its entirety is declining.”
It’s “entirely normal” for antibody levels to drop initially after vaccination and your immune response to the virus to become “contracted” over time, she said. But your body is also creating “highly efficient” memory B cells to fight off COVID-19 long term.
B cells work quickly to generate large quantities of antibodies in the weeks after vaccination, but they typically produce more effective antibodies as time goes on, helping sharpen the long-term response to a virus.
So while reports of waning immunity may sound concerning, that initial decrease in antibody levels may also be necessary in the fight against COVID-19, as it helps fine-tune the immune system’s plan of attack.
A new study published in the journal Science found “robust cellular immune memory” from B cells for at least six months after mRNA vaccination against all circulating strains of the virus — even the highly contagious delta variant.
The researchers found those memory cells, unlike the initial wave of antibodies, continue to learn how to fend off the virus months after vaccination and are actually getting better at it over time.
“That doesn’t sound like ‘waning’ to me,” Gommerman said. “There’s a natural contraction, but waning implies that something bad is happening.”
While reports of waning immunity may sound concerning, the initial decrease in antibody levels may also be necessary in the fight against COVID-19, as it helps fine-tune the immune system’s plan of attack against the virus. (John Woods/The Canadian Press)
Breakthrough infections don’t tell the whole story
Reports of waning immunity and breakthrough infections have sporadically emerged across Canada in places like the Northwest Territories and New Brunswick, but lack important context and data on who is seriously affected and why.
The N.W.T. has been in the midst of a COVID-19 outbreak since mid-August that started in the Sahtu region before spreading to Yellowknife and its surrounding communities. It has infected 1,584 residents.
During that time, there have been 54 hospitalizations attributed to the outbreak, about 17 of which were among fully vaccinated people. A government spokesperson declined to comment on how many of the nine deaths in the territory were among those fully vaccinated.
WATCH | Concerns over waning immunity leads to expansion of boosters in N.W.T.:
N.W.T. expands COVID-19 boosters over concerns about waning immunity
5 days ago
Northwest Territories Chief Public Health Officer Dr. Kami Kandola talks about the impact of the fourth wave and why the territory is offering COVID-19 booster shots to residents as young as 50. 2:58
“New Brunswick has not identified confirmed evidence of waning immunity among COVID-19 cases,” a government spokesperson said in a statement.
In terms of national numbers, 94.7 per cent of all COVID-19 cases in Canada since Dec. 14 have been among those not fully vaccinated, as well as 95.8 per cent of hospitalizations and 94.3 per cent of deaths, according to the Public Health Agency of Canada (PHAC).
That means a total of 520 fully vaccinated Canadians have died of COVID-19 in the nearly 10 months since our vaccine rollout started, compared with 8,520 who were not considered fully vaccinated during that same time period.
“If we have 100 per cent or 95 per cent of the population vaccinated, almost all the cases that we see, including severe cases, will be in vaccinated people — just because most everyone’s vaccinated,” said Dr. Lynora Saxinger, an infectious diseases physician and associate professor at the University of Alberta.
“So that very rare outcome becomes the majority of the outcomes, and seeing an increasing number of cases in vaccinated people over time doesn’t actually mean that the vaccine works less well, necessarily.”
A nurse tends to a patient in the intensive care unit at Scarborough Health Network’s Centenary Hospital in Toronto on Apr. 8. A total of 520 fully vaccinated Canadians have died of COVID-19 in the nearly 10 months since our vaccine rollout started, compared with 8,520 who were not considered fully vaccinated. (Evan Mitsui/CBC)
Underlying conditions key to breakthrough infections
PHAC says fully vaccinated Canadians who do get COVID-19 are also 79 per cent less likely to be hospitalized and 64 per cent less likely to die, backing up new Canadian data showing strong vaccine protection from infection, hospitalization and death.
But key information on the age, underlying health conditions or specific vaccine combination administered to those who were hospitalized or died from COVID-19 two weeks after their second shot is not available in Canada due to health privacy laws.
Older, frailer Canadians living with comorbidities in congregate settings, such as long-term care facilities, are at increased risk of breakthrough infections because their antibody levels drop “much faster” than in the general population, said Gommerman.
A recent preprint study from the Toronto-based Lunenfeld-Tanenbaum Research Institute at Sinai Health analyzed 119 Ontario long-term care residents and 78 staff over four months, finding much lower levels of neutralizing antibodies in the elderly patients.
Gommerman also stresses there’s an important difference between infections and disease.
“We expect people to get infected — even healthy people to get infected — as antibody levels decline, because the only thing that can protect you against a breakthrough infection are antibodies,” she said.
“But we have to think about who we’re looking at, and what underlying comorbidities might be there in people who experienced breakthrough disease.”
Other immunocompromised groups, such as transplant patients, have shown declining protection from COVID-19 vaccines, as evidenced in the New England Journal of Medicine from researchers at the University Health Network (UHN) in Toronto.
WATCH | NACI recommends COVID-19 booster shots for long-term care residents:
NACI recommends COVID-19 booster shots for seniors in long-term care
24 days ago
Amid a global debate over COVID-19 vaccine boosters, the National Advisory Committee on Immunization is recommending third doses for Canada’s most vulnerable, especially seniors in long-term care homes. 1:58
“If you are a healthy person and you’ve been fully vaccinated, you don’t need to worry about getting severe COVID-19,” Gommerman said.
“If you are worried about getting infected with SARS-CoV-2, you should worry because you have people around you who are not vaccinated or who are under-immune.”
Boosters for general population ‘premature’ in Canada
New data from researchers at the Institute for Clinical Evaluative Sciences (ICES) in Toronto, which has not yet been peer-reviewed, found fully vaccinated people over 16 in Ontario were highly protected against both infection and severe COVID-19 after eight months.
ICES’s vaccine estimates, which have not yet been published, show that protection against symptomatic infection does drop — from 94 per cent to 81 per cent — but protection against severe outcomes remained high, at more than 90 per cent.
“The main takeaway is that we don’t need to do boosters at this time for the general population. We can hold off and wait and see — and when we start seeing the waning, then that’s when we should use the boosters,” said Dr. Jeff Kwong, an epidemiologist and senior scientist at ICES.
“It would be premature to do it at this time and not in our best interest, because we’re allowing other variants to emerge potentially if we let the pandemic spread uncontrolled in other parts of the world [where] they’re not vaccinated.”
WATCH | PHAC reviewing data supporting COVID booster shots in Canada:
Public Health officials say they are reviewing the data supporting COVID booster shots
8 days ago
Chief Public Health Officer Dr. Theresa Tam says Canada’s Public Health Agency is reviewing the data supporting third doses of a COVID vaccine and will issue recommendations soon. 1:23
Saxinger said the vast majority of Canadians who get severely ill or hospitalized after full vaccination are the very elderly, the immunocompromised, transplant patients and people with certain types of cancers.
“That group of people, of course, they should get a third dose,” she said. “But even with a third dose, they still are going to remain vulnerable as long as we have circulating virus in the community.”
NEW YORK (AP) — The U.S. syphilis epidemic slowed dramatically last year, gonorrhea cases fell and chlamydia cases remained below prepandemic levels, according to federal data released Tuesday.
The numbers represented some good news about sexually transmitted diseases, which experienced some alarming increases in past years due to declining condom use, inadequate sex education, and reduced testing and treatment when the COVID-19 pandemic hit.
Last year, cases of the most infectious stages of syphilis fell 10% from the year before — the first substantial decline in more than two decades. Gonorrhea cases dropped 7%, marking a second straight year of decline and bringing the number below what it was in 2019.
“I’m encouraged, and it’s been a long time since I felt that way” about the nation’s epidemic of sexually transmitted infections, said the CDC’s Dr. Jonathan Mermin. “Something is working.”
More than 2.4 million cases of syphilis, gonorrhea and chlamydia were diagnosed and reported last year — 1.6 million cases of chlamydia, 600,000 of gonorrhea, and more than 209,000 of syphilis.
Syphilis is a particular concern. For centuries, it was a common but feared infection that could deform the body and end in death. New cases plummeted in the U.S. starting in the 1940s when infection-fighting antibiotics became widely available, and they trended down for a half century after that. By 2002, however, cases began rising again, with men who have sex with other men being disproportionately affected.
The new report found cases of syphilis in their early, most infectious stages dropped 13% among gay and bisexual men. It was the first such drop since the agency began reporting data for that group in the mid-2000s.
However, there was a 12% increase in the rate of cases of unknown- or later-stage syphilis — a reflection of people infected years ago.
Cases of syphilis in newborns, passed on from infected mothers, also rose. There were nearly 4,000 cases, including 279 stillbirths and infant deaths.
“This means pregnant women are not being tested often enough,” said Dr. Jeffrey Klausner, a professor of medicine at the University of Southern California.
What caused some of the STD trends to improve? Several experts say one contributor is the growing use of an antibiotic as a “morning-after pill.” Studies have shown that taking doxycycline within 72 hours of unprotected sex cuts the risk of developing syphilis, gonorrhea and chlamydia.
In June, the CDC started recommending doxycycline as a morning-after pill, specifically for gay and bisexual men and transgender women who recently had an STD diagnosis. But health departments and organizations in some cities had been giving the pills to people for a couple years.
Some experts believe that the 2022 mpox outbreak — which mainly hit gay and bisexual men — may have had a lingering effect on sexual behavior in 2023, or at least on people’s willingness to get tested when strange sores appeared.
Another factor may have been an increase in the number of health workers testing people for infections, doing contact tracing and connecting people to treatment. Congress gave $1.2 billion to expand the workforce over five years, including $600 million to states, cities and territories that get STD prevention funding from CDC.
Last year had the “most activity with that funding throughout the U.S.,” said David Harvey, executive director of the National Coalition of STD Directors.
However, Congress ended the funds early as a part of last year’s debt ceiling deal, cutting off $400 million. Some people already have lost their jobs, said a spokeswoman for Harvey’s organization.
Still, Harvey said he had reasons for optimism, including the growing use of doxycycline and a push for at-home STD test kits.
Also, there are reasons to think the next presidential administration could get behind STD prevention. In 2019, then-President Donald Trump announced a campaign to “eliminate” the U.S. HIV epidemic by 2030. (Federal health officials later clarified that the actual goal was a huge reduction in new infections — fewer than 3,000 a year.)
There were nearly 32,000 new HIV infections in 2022, the CDC estimates. But a boost in public health funding for HIV could also also help bring down other sexually transmitted infections, experts said.
“When the government puts in resources, puts in money, we see declines in STDs,” Klausner said.
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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.
WASHINGTON (AP) — Scientists can’t know precisely when a volcano is about to erupt, but they can sometimes pick up telltale signs.
That happened two years ago with the world’s largest active volcano. About two months before Mauna Loa spewed rivers of glowing orange molten lava, geologists detected small earthquakes nearby and other signs, and they warned residents on Hawaii‘s Big Island.
Now a study of the volcano’s lava confirms their timeline for when the molten rock below was on the move.
“Volcanoes are tricky because we don’t get to watch directly what’s happening inside – we have to look for other signs,” said Erik Klemetti Gonzalez, a volcano expert at Denison University, who was not involved in the study.
Upswelling ground and increased earthquake activity near the volcano resulted from magma rising from lower levels of Earth’s crust to fill chambers beneath the volcano, said Kendra Lynn, a research geologist at the Hawaiian Volcano Observatory and co-author of a new study in Nature Communications.
When pressure was high enough, the magma broke through brittle surface rock and became lava – and the eruption began in late November 2022. Later, researchers collected samples of volcanic rock for analysis.
The chemical makeup of certain crystals within the lava indicated that around 70 days before the eruption, large quantities of molten rock had moved from around 1.9 miles (3 kilometers) to 3 miles (5 kilometers) under the summit to a mile (2 kilometers) or less beneath, the study found. This matched the timeline the geologists had observed with other signs.
The last time Mauna Loa erupted was in 1984. Most of the U.S. volcanoes that scientists consider to be active are found in Hawaii, Alaska and the West Coast.
Worldwide, around 585 volcanoes are considered active.
Scientists can’t predict eruptions, but they can make a “forecast,” said Ben Andrews, who heads the global volcano program at the Smithsonian Institution and who was not involved in the study.
Andrews compared volcano forecasts to weather forecasts – informed “probabilities” that an event will occur. And better data about the past behavior of specific volcanos can help researchers finetune forecasts of future activity, experts say.
(asterisk)We can look for similar patterns in the future and expect that there’s a higher probability of conditions for an eruption happening,” said Klemetti Gonzalez.
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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.
Waymo on Tuesday opened its robotaxi service to anyone who wants a ride around Los Angeles, marking another milestone in the evolution of self-driving car technology since the company began as a secret project at Google 15 years ago.
The expansion comes eight months after Waymo began offering rides in Los Angeles to a limited group of passengers chosen from a waiting list that had ballooned to more than 300,000 people. Now, anyone with the Waymo One smartphone app will be able to request a ride around an 80-square-mile (129-square-kilometer) territory spanning the second largest U.S. city.
After Waymo received approval from California regulators to charge for rides 15 months ago, the company initially chose to launch its operations in San Francisco before offering a limited service in Los Angeles.
Before deciding to compete against conventional ride-hailing pioneers Uber and Lyft in California, Waymo unleashed its robotaxis in Phoenix in 2020 and has been steadily extending the reach of its service in that Arizona city ever since.
Driverless rides are proving to be more than just a novelty. Waymo says it now transports more than 50,000 weekly passengers in its robotaxis, a volume of business numbers that helped the company recently raise $5.6 billion from its corporate parent Alphabet and a list of other investors that included venture capital firm Andreesen Horowitz and financial management firm T. Rowe Price.
“Our service has matured quickly and our riders are embracing the many benefits of fully autonomous driving,” Waymo co-CEO Tekedra Mawakana said in a blog post.
Despite its inroads, Waymo is still believed to be losing money. Although Alphabet doesn’t disclose Waymo’s financial results, the robotaxi is a major part of an “Other Bets” division that had suffered an operating loss of $3.3 billion through the first nine months of this year, down from a setback of $4.2 billion at the same time last year.
But Waymo has come a long way since Google began working on self-driving cars in 2009 as part of project “Chauffeur.” Since its 2016 spinoff from Google, Waymo has established itself as the clear leader in a robotaxi industry that’s getting more congested.
Electric auto pioneer Tesla is aiming to launch a rival “Cybercab” service by 2026, although its CEO Elon Musk said he hopes the company can get the required regulatory clearances to operate in Texas and California by next year.
Tesla’s projected timeline for competing against Waymo has been met with skepticism because Musk has made unfulfilled promises about the company’s self-driving car technology for nearly a decade.
Meanwhile, Waymo’s robotaxis have driven more than 20 million fully autonomous miles and provided more than 2 million rides to passengers without encountering a serious accident that resulted in its operations being sidelined.
That safety record is a stark contrast to one of its early rivals, Cruise, a robotaxi service owned by General Motors. Cruise’s California license was suspended last year after one of its driverless cars in San Francisco dragged a jaywalking pedestrian who had been struck by a different car driven by a human.
Cruise is now trying to rebound by joining forces with Uber to make some of its services available next year in U.S. cities that still haven’t been announced. But Waymo also has forged a similar alliance with Uber to dispatch its robotaxi in Atlanta and Austin, Texas next year.
Another robotaxi service, Amazon’s Zoox, is hoping to begin offering driverless rides to the general public in Las Vegas at some point next year before also launching in San Francisco.
