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Reinfections from Omicron subvariant BA.2 seem rare, study finds, making 'new wave' unlikely – CBC News

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Getting infected more than once by subvariants in the Omicron family does seem possible, but appears rare, scientists in Denmark found in a recent real-world study — offering reassurance that countries won’t experience another sudden surge of infections.

The early research, which was published online as a preprint on Tuesday and has not yet been peer-reviewed, involved an analysis of recent SARS-CoV-2 infections by a team from the Statens Serum Institut (SSI), a top Danish public health institute.

Many of those were the highly-contagious BA.2 subvariant, which is now dominant in that country — and on the rise elsewhere — after squeezing out other Omicron subvariants featuring different mutations, including the original lineage, as well as BA.1, BA.1.1 and BA.3.

Out of nearly two million infections logged in Denmark between mid-November and mid-February, the researchers zeroed in on those who tested positive twice between 20 and 60 days apart, and whose infections had gone through previous genomic surveillance and were labelled as a specific subvariant.

Fewer than 1,800 people hit those criteria, and a subset of close to 1,000 samples were randomly selected for sequencing.

The team ended up finding 187 cases of reinfection, including 47 instances where BA.2 reinfections happened shortly after a BA.1 infection, “mostly in young unvaccinated individuals with mild disease not resulting in hospitalization or death,” the team wrote. 

One of the researchers, Dr. Troels Lillebæk, chair of Denmark’s SARS-CoV-2 Variant Assessment Committee, told CBC News this offers the first evidence of reinfections among members of the Omicron family, but it appears this is a “quite rare phenomenon.”

“If it was a major problem that you could catch BA.2 after BA.1, you could imagine a new wave,” he said.

“This does not really point in that direction.”

BA.2 cases rising in Canada

After weeks of uncertainty, it’s a welcome finding, following the upward spike in BA.2 cases in multiple countries that sent scientists scrambling to understand whether the heavily-mutated subvariant could prolong this year’s Omicron wave — or even spark a new one.

In Denmark, BA.2 infections now make up roughly nine in 10 cases, with cases also rising in countries including Norway, South Africa and the U.K.

Here in Canada, the subvariant was barely a blip in federal data by early January, but the latest-available data by month’s end suggest it makes up roughly one in 10 cases, with recent data still accumulating. 

Its rise comes as the overall Omicron wave is subsiding, and while much of the country is further loosening or outright dropping COVID-related restrictions, granting Canadians the opportunity to socialize indoors more freely than at many points during this more than two-year pandemic.

Employees are vaccinated at a COVID-19 vaccination clinic at Montreal’s CAE headquarters in April 2021. It’s unlikely Canada will experience another wave of infections tied to the BA.2 subvariant, experts say, in part thanks to the country’s high vaccination rate. (Paul Chiasson/The Canadian Press)

The virus will still be circulating, said Dr. Zain Chagla, an infectious diseases specialist and professor at McMaster University in Hamilton, Ont., but based on the emerging evidence about how BA.2 operates, it’s unlikely Canada will experience another wave of infections tied to this subvariant.

That’s in part thanks to Canada’s high vaccination rate, he said, coupled with the spike in exposure brought on by the original Omicron surge which infected huge numbers of Canadians in recent months, providing millions with hybrid immunity to this evolving virus.

“So many people are vaccinated and boosted or have had BA.1 recently that they’re not very likely to be reinfected so quickly afterwards with BA.2,” echoed Angela Rasmussen, a virologist with the University of Saskatchewan’s Vaccine and Infectious Disease Organization (VIDO).

Questions over disease severity

While its capacity to transmit and reinfect is becoming more clear, there are still questions over what level of serious disease BA.2 is capable of causing. 

Real-world data on clinical severity from South Africa, the U.K., and Denmark, where immunity from vaccination or natural infection is high, shows no reported difference in severity between BA.2 and BA.1, the World Health Organization noted on Tuesday.

“Now, that could change as BA.2 pushes out BA.1 and makes its way into higher risk [unvaccinated] people,” noted Jason Kindrachuk, an assistant professor in medical microbiology and infectious diseases at the University of Manitoba, in an email exchange with CBC News.

WATCH | Pfizer testing Omicron-based vaccine amid concerns about subvariant: 

Pfizer testing Omicron-based vaccine amid concerns about twin variant

29 days ago

Duration 2:02

Pfizer has started testing an Omicron-based COVID-19 vaccine to see if it can prevent infection and not only severe illness. The testing comes as researchers investigate an emerging variant described as Omicron’s twin. 2:02

Early preliminary laboratory results from a team in Japan using hamster models — which allowed the researchers to infect subjects that didn’t have any prior immunity — did suggest BA.2 may cause more severe disease than BA.1 in those without previous vaccination or viral infection.

The findings, recently published online as a preprint, suggest the fast-spreading subvariant may be closer to earlier variants in terms of disease severity.

But Rasmussen, from VIDO in Saskatchewan, stressed that animal studies don’t paint a full picture of how pathogens like SARS-CoV-2 will impact humans. 

And while scientists should continue studying BA.2, she said the bigger focus should be on increasing vaccination rates and booster shot uptake to give people their best chance at fending off potential infections — whether that’s an Omicron reinfection, or exposure to future variants of this ever-evolving virus.

“We should start thinking about the next variant that’s going to come along rather than worrying so much about BA.2,” she warned.

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BC Cancer launches lung-screening program | BC Gov News – BC Gov News

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Warren Clarmont, provincial director, Indigenous Cancer Control, BC Cancer –

“Indigenous people are experiencing higher incidences of lung cancer when compared to other B.C. residents. The introduction of a provincewide lung-screening program will help reduce barriers to access for Indigenous people across B.C. We hope that with this new program, more lives will be saved through culturally safe and accessible screening for eligible First Nations, Métis and Inuit people.”

Sarah Roth, president and CEO, BC Cancer Foundation –

“This first-in-Canada provincewide lung cancer screening program would not be possible without our incredible community of donors. We are so proud to funnel their support, in partnership with the Province and BC Cancer, to help bring this life-saving prevention and early-detection tool to high-risk people across B.C., regardless of where they live. It is our deepest hope that it will change the game for the deadliest cancer in the province.”

Dr. Kim Nguyen Chi, chief medical officer, BC Cancer –

“BC Cancer’s new Lung Screening Program will help diagnose lung cancer at an early stage before people develop symptoms. Cancer screening for early detection is a key tool in the fight against cancer. Earlier detection of cancer means treatment that can be less invasive and have faster recovery and higher rates of cure.”

Dr. Craig Earle, CEO, Canadian Partnership Against Cancer (CPAC) –

“CPAC congratulates British Columbia and the BC Cancer team for acting quickly to implement a provincewide lung cancer screening program and supporting early diagnosis for people at high risk for this disease. Because of the solid evidence showing that lung cancer screening saves lives, implementing screening programs is a priority initiative in the Canadian strategy for cancer control. Co-creating these programs across the country with First Nations, Inuit, Métis and equity-deserving communities will help achieve the strategy’s vision of equitable access to high-quality, culturally safe cancer prevention and care for all people in Canada.”

Shannon McCrae, B.C.  lung-screening trial participant and lung cancer survivor –

“My best friend passed away from lung cancer, so I knew first-hand that lung cancer can be a silent killer. I was a smoker for over 20 years, so when I saw an ad about the BC Cancer lung-screening trial, I registered on the spot. I was shocked when the screening results came back positive even though I displayed no symptoms. The cancer was removed immediately after I was notified about my results. I can say with confidence and gratitude that early detection and the B.C. Lung Screening Pogram saved my life. I’d like to encourage all who qualify for the screening to enrol.”

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Older adults face higher risks for long COVID, shots don’t prevent it: U.S. study – Global News

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New U.S. research on long COVID-19 provides fresh evidence that it can happen even after breakthrough infections in vaccinated people, and that older adults face higher risks for the long-term effects.

In a study of veterans published Wednesday, about one-third who had breakthrough infections showed signs of long COVID.

A separate report from the Centers for Disease Control and Prevention found that up to a year after an initial coronavirus infection, 1 in 4 adults aged 65 and older had at least one potential long COVID health problem, compared with 1 in 5 younger adults.

Long COVID refers to any of more than two dozens symptoms that linger, recur or first appear at least one month after a coronavirus infection. These can affect all parts of the body and may include fatigue, shortness of breath, brain fog and blood clots.

Read more:

Omicron COVID-19 variant likely to re-infect ‘over and over again,’ experts say

Coronavirus vaccines that help prevent initial infections and serious illnesses provide some protection against long COVID but mounting research shows not as much as scientists had first hoped.

The veterans study published in Nature Medicine reviewed medical records of mostly white male veterans, aged 60, on average. Of the 13 million veterans, almost 3 million had been vaccinated last year, through October.

About 1%, or nearly 34,000, developed breakthrough infections. Lead author Dr. Ziyad Al-Aly noted that the study was done before the highly contagious omicron variant appeared at the end of the year and said the rate of breakthrough infections has likely increased.

Breakthrough infections and long COVID symptoms were more common among those who had received Johnson & Johnson’s single-dose shot compared with two doses of either Moderna or Pfizer vaccines. Whether any had received booster shots is not known; the first booster wasn’t OK’d in the U.S. until late September.


Click to play video: 'WHO Director General re-elected for five more years: ‘Luck brought me all the way here’'



1:15
WHO Director General re-elected for five more years: ‘Luck brought me all the way here’


WHO Director General re-elected for five more years: ‘Luck brought me all the way here’

Overall, 32% had long COVID symptoms up to six months after breakthrough infections. That’s compared with 36% of unvaccinated veterans who had been infected and developed long COVID.

Vaccination reduced the chances for any long COVID symptoms by a “modest” 15%,” although it cut the risk in half for lingering respiratory or clotting problems, said Al-Aly, a researcher with Washington University and the Veterans Affairs health system in St. Louis. These symptoms included persistent shortness of breath or cough and blood clots in lungs or veins in the legs.

Infectious disease expert Dr. Kristin Englund, who runs a center for long COVID patients at the Cleveland Clinic, said the Nature Medicine study mirrors what she sees at her clinic. Long COVID patients there include people who were vaccinated and received boosters.

“As we have no clear treatments for long COVID, it is important for everyone to get vaccinated and use other proven methods of prevention such as masking and social distancing in order to prevent infections with COVID and thus long COVID,” Englund said.


Click to play video: 'Monkeypox patterns of transmission ‘not typical,’ but virus is ‘containable’: WHO'



2:11
Monkeypox patterns of transmission ‘not typical,’ but virus is ‘containable’: WHO


Monkeypox patterns of transmission ‘not typical,’ but virus is ‘containable’: WHO

The CDC report, released Tuesday, used medical records for almost 2 million U.S. adults from the start of the pandemic in March 2020 to last November. They included 353,000 who had COVID-19. Patients were tracked for up to a year to determine if they developed any of 26 health conditions that have been attributed to long COVID.

Those who had COVID were much more likely than other adults without COVID to develop at least one of these conditions, and risks were greatest for those aged 65 and older. Information on vaccination, sex and race was not included.

Breathing problems and muscle aches were among the most common conditions.

Older adults’ risks were higher for certain conditions, including strokes, brain fog, kidney failure and mental health problems. The findings are worrisome because those conditions can hasten older adults’ needs for long-term care, the report authors said.

They stressed that routine assessment of all COVID patients “is critical to reduce the incidence” of long COVID.

© 2022 The Associated Press

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Monkeypox: Cases in Canada climb to 16, PHAC says – CTV News

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The Public Health Agency of Canada (PHAC) says it has now confirmed a total of 16 cases of monkeypox in the country, all in Quebec.

The latest update on the spread of the viral disease came in a statement issued Wednesday evening.

The statement says Canada’s National Microbiology Laboratory continues to receive samples from multiple jurisdictions for confirmation testing.

“At this time, cases of monkeypox are being identified and treated by local health clinics,” the statement said.

“There is ongoing planning with provinces and territories to provide access to approved vaccines in Canada that, if required, can be used in managing monkeypox in their jurisdiction.”

The PHAC says it has given Quebec a small shipment of the smallpox vaccine Imvamune from Canada’s National Emergency Strategic Stockpile, with other jurisdictions able to receive some supply.

In April, Public Services and Procurement Canada submitted a tender to purchase 500,000 doses of the Imvamune vaccine between 2023 and 2028.

There is currently no need for mass immunizations, the PHAC says.

“I know Canadians are concerned,” Duclos said in a statement Tuesday. “The Government of Canada is prepared to respond to emerging public health events and takes precautions to prevent the introduction and spread of communicable diseases.”

The national laboratory received its first samples during the week of May 16, before announcing the first two cases of monkeypox identified in Quebec on May 19. That number rose to five cases the following day.

Since then, other possible cases of monkeypox have emerged in Canada. On Wednesday, Toronto public health authorities said they identified two new suspected cases in the city, along with one probable case currently under investigation.

Monkeypox is a rare disease that was first discovered among colonies of monkeys used for research. Historically, it has also been transmitted from animals to humans, with the first human case recorded in 1970. The virus can spread through close contact with an infected animal, human, or contaminated material.

The federal government is prepared to help provinces and territories develop their own means of testing for the disease in order to monitor it more easily, Duclos said.

“Our surveillance system is working, as is our testing system, though we will continue to refine both, including supporting provinces and territories in building their own testing capacities so cases can be identified and traced even more efficiently,” Duclos’ statement read.

The government will also provide updated guidance on preventing infection, as well as procedures around isolation and case management. Canadians can expect the National Advisory Committee on Immunization (NACI) to provide additional guidance in the coming weeks as well.

In his statement, Duclos emphasized that the emergence of monkeypox is not the same as COVID-19, which quickly spiralled into a worldwide pandemic.

“I want to re-iterate to Canadians that this is a different situation than we saw ourselves in with the emergence of COVID-19,” Duclos’ statement read. “While global understanding of the monkeypox virus is still evolving, we do have a supply of vaccines, which we will be sure to maintain, and we are working hand-in-hand with our provincial and territorial counterparts to roll out our response plan as quickly as possible.”

In an effort to avoid contracting the disease, Canadians are advised to physically distance from those around them, frequently wash their hands and wear masks in crowded environments.

With files from CTV News and The Canadian Press

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