A British public health study has found that protection from either of the two most commonly used COVID-19 vaccines against the now prevalent Delta variant of the coronavirus weakens within three months.
It also found that those who get infected after receiving two shots of either the Pfizer-BioNTech or the AstraZeneca vaccine may be of greater risk to others than under previous variants of the coronavirus.
Based on more than three million nose and throat swabs taken across Britain, the Oxford University study found that 90 days after a second shot of the Pfizer or AstraZeneca vaccine, their efficacy in preventing infections had slipped to 75% and 61% respectively.
That was down from 85% and 68%, respectively, seen two weeks after a second dose. The decline in efficacy was more pronounced among those aged 35 years and older than those below that age.
“Both of these vaccines, at two doses, are still doing really well against Delta… When you start very, very high, you got a long way to go,” said Sarah Walker, an Oxford professor of medical statistics and chief investigator for the survey.
Walker was not involved in work on AstraZeneca’s vaccine, which was initially developed by immunology experts at Oxford.
The researchers would not project how much more the protection would drop over time, but suggested that the efficacy of the two vaccines studied would converge within 4-5 months after the second shot.
4th wave of the COVID-19 pandemic underway in Canada: Dr. Tam
Highlighting the increased risk of contagion from the Delta variant, the study also showed that those who do get infected despite being fully vaccinated tend to have a viral load similar to the unvaccinated with an infection, a clear deterioration from when the Alpha variant was still dominant in Britain.
The Oxford findings are in line with an analysis by the U.S. Centers for Disease Control and Prevention (CDC) and come as the U.S. government outlines plans to make COVID-19 vaccine booster shots widely available next month amid a rise in Delta variant infections. It has cited data indicating diminishing protection from the vaccines over time.
Israel began administering third Pfizer doses last month to confront a surge in local infections driven by Delta. Several European countries are also expected to begin offering boosters to the elderly and people with weak immune systems.
Pfizer has said its vaccine’s efficacy drops over time. Last month AstraZeneca said it was still looking into how long its vaccine’s protection lasts and whether a booster dose would be needed to keep up immunity.
“The fact that we do see … more viral load hints (…) that indeed herd immunity might become more challenging,” said co-author Koen Pouwels, also of Oxford University.
Will Canada be able to reach herd immunity against COVID-19?
Herd immunity is when a large enough portion of the population is immune to a pathogen, either by vaccination or prior infection, stopping infection numbers from growing.
“Vaccines are probably best at preventing severe disease and slightly less at preventing transmission,” said Pouwels.
The authors cautioned that the viral concentration in the throat was only a rough proxy for severity of symptoms and that they had no new data on the duration of infections.
The survey, which has yet to be peer-reviewed before publication in a scientific journal, underscores concerns by scientists that the Delta variant, first identified in India, can infect fully vaccinated people at a greater rate than previous lineages, and that the vaccinated could more easily transmit it.
To contrast periods before and after Delta became prevalent, the Oxford researchers analyzed about 2.58 million swabs taken from 380,000 randomly picked adults between Dec. 1, 2020, and May 16, 2021, and 810,000 test results from 360,000 participants between May 17 and Aug. 1.
The study was conducted in partnership with Britain’s Office of National Statistics (ONS) and the Department for Health and Social Care (DHSC).
Impact of the Delta variant
© 2021 Reuters
Canadian wastewater surveillance expanding to new public health threats: Tam – CP24
Laura Osman, The Canadian Press
Published Friday, August 12, 2022 2:53PM EDT
Last Updated Friday, August 12, 2022 4:53PM EDT
OTTAWA – Plans are underway to sift through Canadian sewage to test for and measure monkeypox, polio and other potential health threats, the country’s chief public health officer said Friday.
Over the course of the COVID-19 pandemic, wastewater detection became a key way to track the spread of the virus, especially as free lab tests for individuals were phased out for all but a few in later waves.
Dr. Theresa Tam said the experts at the National Microbiology Lab have now discovered a promising approach to detect monkeypox in wastewater and will use the infrastructure developed during the pandemic to look for it.
“Moving forwards, it could form part of our monitoring of the disease activity going up and down across the country,” Tam said at a media briefing.
Tam said the method is complicated, but they’ve landed on something that can “probably” be used more broadly. How that monitoring fits into the Public Health Agency of Canada’s surveillance efforts on monkeypox is not yet clear.
The monkeypox disease comes from the same family of viruses that cause smallpox, which the World Health Organization declared eradicated around the globe in 1980.
Cases of monkeypox began to appear around the world in non-endemic countries in May.
Just this week the number of Canadian cases surpassed 1,000, though there are early signs the virus may now be spreading at a slower rate, Tam said.
The Public Health Agency of Canada also intends to start testing for polio as “soon as possible” after U.S. health officials found the polio virus in New York City’s wastewater.
The devastating virus was eradicated from Canada in 1994 and until very recently has not been found in the United States since 1993. Cases have now freshly emerged in Western nations with traditionally high rates of vaccinated people.
A positive case was discovered in New York last month.
The presence of the polio virus in the city’s wastewater suggests the virus is likely circulated locally, health authorities from the city, New York state and the U.S. federal government said Friday.
“We’re already starting to look at what the options are,” Tam said of monitoring for polio in Canada.
Polio tests are just now coming online in Ontario, said Eric Arts, a microbiology and immunology professor at Western University.
The COVID-19 pandemic proved how useful waste can be compared to person-by-person tests, he said, especially when it comes to early detection.
“Instead of testing hundreds of thousands of people kind of randomly to determine if they’re infected with a specific pathogen, or one that we don’t even know is circulating, you can just get a wastewater sample and test 100,000 people with one test,” he said.
Wastewater surveillance can be adapted for other things as well, she said. Even before the pandemic, Tam said the public health agency was looking at ways to scan for antimicrobial resistant organisms, or superbugs as they’re often called.
Wastewater detection is still imperfect though, Tam warned.
“You’re dealing with a slurry of many things with a lot of DNA, RNA, all sorts of things,” Tam said, putting it politely.
That slurry includes countless viruses and virus mutations. Some vaccines, like the oral vaccine for polio given in some countries that includes a live, attenuated virus, can also be confused with the real thing in a wastewater sample.
“It’s not terribly easy,” she said.
Different countries use different methods, Tam said, and even within Canada there’s a lot of innovation happening.
“I think one of the roles of our lab is to then look at the best methods and try and bring some standardization and guidance to that testing,” she said.
This report by The Canadian Press was first published Aug. 12, 2022.
– With files from Adina Bresge in Toronto and The Associated Press
Foreigners flock to Canada for monkeypox vaccine – Medical Xpress
With the monkeypox vaccine in short supply in the United States, thousands of foreigners, including Americans are flocking to Montreal to get their shots.
Canada’s second-largest city, located about 70 kilometers (43 miles) north of the US border in Quebec province, has decided to make the vaccine available to all those who consider themselves to be at risk.
ackRobb Stilson, an art director from Denver, Colorado, took advantage of the opportunity during a visit to Montreal last week.
“It’s very difficult in the States to get vaccinated,” Stilson said as he lined up to get a shot at a pop-up vaccination center together with his husband and two daughters. “I’ve friends who have waited 8 or 9 hours to get in.”
Because contact tracing is difficult, authorities in Montreal decided to offer the vaccine to all those who are at risk to stem the spread of the virus.
“As tourists, they may participate in activities that may expose them and so in a way, we’re combatting the pandemic by letting them become vaccinated here so that they don’t transmit the infection either here or when they go back home,” Donald Vinh, infectious disease specialist at the McGill University Health Center, told AFP.
Since the vaccination campaign was launched in mid-May, as soon as the first cases of monkeypox were detected, Montreal has inoculated 18,500 people, 13 percent of them foreigners.
The goal is to administer 25,000 doses and vaccinate some 75-80 percent of the population deemed to be at risk, in particular men who have sex with men or with multiple partners.
“I hope the strategy used by the public health agency of Montreal is a beacon for other public health agencies to use as a vaccination strategy,” Vinh added.
In the western province of British Columbia, health authorities decided last week they will no longer offer the vaccine to foreigners citing limited supplies and the fact that it was becoming more available in the United States.
Faced with a lack of available doses, American health authorities on Tuesday authorized a new injection procedure which will make it possible to inoculate five times the number of people with the same amount of the drug.
As of August 11, Canada has registered 1,059 confirmed cases of monkeypox, but authorities see signs of infections beginning to slow.
© 2022 AFP
Foreigners flock to Canada for monkeypox vaccine (2022, August 12)
retrieved 13 August 2022
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.
Elevated risk of Monkeypox in Saskatchewan: SHA – CTV News Regina
The Saskatchewan Health Authority (SHA) has alerted the public to the elevated risk of acquiring Monkeypox through anonymous sexual contact.
“So far we’ve had three cases, who were exposed out of the province,” said Saskatchewan’s Chief Medical Health Officer, Dr. Saqib Shahab.
“We think the situation has changed now, in the last week. Where we have had evidence of exposures happening in Saskatchewan, in many cases happening through anonymous sexual contacts with people who have been coming into the province.”
Shahab noted that the exposures were happening almost exclusively to those in the gay, bisexual and men who have sex with men (gbMSM) community.
“We think now that there is a higher risk that we may see ongoing transmission within Saskatchewan … particularly in this community.”
Shahab noted that these trends were similar to what is being seen across Canada. He urged those in Saskatchewan at risk not to hesitate and reach out.
“If you belong to the gbMSM community it’s really important that at the first sign of illness you do contact the Healthline (811) for advice and seek testing and isolate till the diagnosis is made.”
INCREASED ELIGIBILITY FOR VACCINES
The SHA announced that Monkeypox vaccine requirements would be expanded to both post and pre exposure, following the alert.
The Public Health Agency of Canada has set aside 99,000 doses of the vaccine, with 50,000 doses being given to provinces so far, according to Shahab.
Those eligible for vaccinations include select high-risk contacts 18 years and older who are identified ideally within 4 days and up to 14 days after an exposure. Those who are at a high risk of exposure are also eligible. The SHA’s criteria includes:
- Are transgender or self-identify as two spirit, bisexual, gay or men who have sex with men (MSM)
And one or more of the following:
- Have had a recent sexually transmitted infection (in the past six months);
- Report having had two or more sexual partners in the past six months;
- Had (in the past six months) or plan to have sexual contact involving an exchange of money or other goods for sexual services;
- Report having had (in the past six months) or planning to have sexual contact at an event or social gathering where there is MSM-themed sexual activity (sauna, bath house, club);
- Have had (in the past six months) or plan to have sexual contact with an anonymous partner (at an event or via a hook-up app);
- Planning to travel in the next three months to an area in Canada or internationally currently reporting monkeypox cases;
- Individuals 18 years and older who work or volunteer at an event or social gathering where there is MSM themed sexual activity (sauna, bath house, club).
The SHA has outlined how to properly isolate and protect others while contagious with Monkeypox on its website.
Monkeypox is a rare viral illness that causes fever, headache, swollen lymph nodes and lethargy, followed by the development of a rash over a person’s body. The disease is not easily spread from person to person according to the SHA. Monkeypox is spread through:
- Close, personal, often skin-to-skin contact.
- Touching bodily fluids or lesions of a person who is sick with the disease.
- Exposure to contaminated objects such as bed linens or clothing.
There are currently around 30,000 Monkeypox cases globally, with approximately 1,000 of those occurring in Canada.
Saskatchewan’s current criteria for vaccination and its overall approach has been informed by other provincial responses such as in Ontario and Quebec, according to Shahab.
“We really hope that by this approach in Saskatchewan we can try to avert a quick or high surge of cases and also prevent further transmission.”
Rogers, Shaw formalize planned Freedom sale to Quebecor – BNN Bloomberg
Taiwan blames politics for cancellation of global Pride event – CNN
Researchers in South America Discover a New Species of Tiny but Tough Dinosaurs – ScienceAlert
Silver investment demand jumped 12% in 2019
Europe kicks off vaccination programs | All media content | DW | 27.12.2020 – Deutsche Welle
Global Media Markets, 2015-2020, 2020-2025F, 2030F – TV and Radio Broadcasting, Film and Music, Information Services, Web Content, Search Portals And Social Media, Print Media, & Cable – GlobeNewswire
Health23 hours ago
Coronavirus Update: Pregnant women who receive mRNA COVID-19 vaccines aren't more at risk of miscarriage, stillbirth, new study confirms – The Globe and Mail
News23 hours ago
More Canadians report stronger attachment to their language than to Canada: poll – CTV News
Art17 hours ago
Remembering Dori Klaaren and her art – Niagara Frontier Publications
Health22 hours ago
Canada hasn’t needed to declare monkeypox an emergency, top doctor says. Here’s why – Global News
Science14 hours ago
Remains of small armor-plated dinosaur found in Argentina – Mint Lounge
Economy19 hours ago
Charting the Global Economy: US Inflation Comes Off the Boil – BNN Bloomberg
Science3 hours ago
Researchers in South America Discover a New Species of Tiny but Tough Dinosaurs – ScienceAlert
Investment23 hours ago
FXM VENTURE – Offers News Investment Platform – GlobeNewswire