By Sameer Elsayed, Professor of Medicine, Pathology and Laboratory Medicine, and Epidemiology and Biostatistics, Western University Ontario (Canada), Nov 14 (The Conversation) Public health experts in the Northern Hemisphere are predicting a fall/winter respiratory virus season for the ages — one that highlights the importance of global surveillance efforts and vaccines as tools in the fight against influenza (flu) and COVID-19.
Making sense of COVID-19’s impact on seasonal flu Prior to the COVID-19 pandemic, the annual respiratory virus season in northern and southern climates was an epidemic of sorts, one that was characterised by a rapid uptick in the rate of influenza (flu) and of influenza-like illness beginning in mid-fall, peaking in mid-winter and winding down in mid-spring.
The previously predictable pattern of influenza activity in the global North and South has become somewhat unpredictable in post-pandemic seasons.
In the United States, approximately 36 million infections, 390,000 hospitalisations and 25,000 deaths due to flu were reported during the 2019-20 season.
In contrast, minimal influenza activity was noted in 2020-21 while the 2021-22 season saw a four-fold decline in activity compared to pre-pandemic seasons.
Implementation of strict public health measures during the COVID-19 pandemic was instrumental in reducing the incidence of flu and flu-like illnesses during the past two respiratory virus seasons in both hemispheres.
However, the relaxation of these measures is expected to promote a tidal wave of respiratory virus infections in the weeks to come.
These infections include influenza, SARS-CoV-2 and Respiratory Syncytial Virus (RSV), which often affects children.
Influenza in the Southern Hemisphere Despite the impact of COVID-19 on global health and the almost negligible level of seasonal influenza activity over the past two years, the Southern Hemisphere experienced a major shift in influenza activity during the 2022 respiratory virus season.
In Chile, the season began with a burst of influenza B activity in January, followed by a relative lull in March and April, and then a surge in influenza A that peaked in June.
In contrast, Australia’s flu season started in March, had a record peak in June, and was dominated throughout by influenza A.
What’s in store for fall and winter? Unlike seasonal influenza, COVID-19 primarily behaves as a pandemic virus, with simultaneous, high-level viral transmission in all parts of the globe. COVID-19 activity may be “seasonal” in some respects, with higher rates of transmission during the fall and winter months when people are indoors more often than not and, consequentially, less socially-distanced.
The 2022 Southern Hemisphere experience serves as a harbinger for what to expect during the 2022-23 respiratory virus season in northern climates.
In the North, the respiratory virus season is already off to an early and blazing start, particularly in the US and Canada, and appears destined to wreak havoc on health-care systems that are already struggling from the impact of COVID-19.
The importance of influenza vaccination Vaccination is one of the most effective public health interventions in our battle against influenza and COVID-19.
Recommendations on the composition of flu vaccines are made biannually by the World Health Organisation (WHO) several months in advance of the forthcoming respiratory virus season in each respective hemisphere.
However, licensing of influenza vaccines generally falls under national jurisdictions. Similar vaccine formulations are approved for use in the US, Canada, United Kingdom and other northern countries, and are now widely available.
Flu vaccine composition for the 2022-23 respiratory virus season in northern latitudes is based on surveillance of circulating influenza virus strains during the most recent respiratory virus season in the Southern Hemisphere.
The WHO has recommended both quadrivalent vaccines (containing four strains) and trivalent vaccines (containing three strains), with no preference given to either formulation.
The quadrivalent vaccine contains two inactivated strains of influenza A (H1N1 and H3N2) and two inactivated strains of influenza B. The trivalent vaccine is similar with the exception of having a single inactivated strain of influenza B.
How effective are flu shots? Vaccine-mediated protection against influenza infection, severe illness and death has immense public health ramifications, yet is often misunderstood.
Vaccine effectiveness varies from one respiratory virus season to another and hinges on several factors, including the degree of vaccine mismatch with circulating strains, the use of high-dose versus standard-dose vaccines, prior influenza illness or vaccination, age, general health status, and public health measures such as social distancing, medical mask use, and travel restrictions.
Flu vaccines tend to confer a greater degree of protection against influenza B and influenza A H1N1 subtypes, with a lower degree of effectiveness against the influenza A H3N2 subtype.
Research has shown that the effectiveness of standard-dose flu vaccines in preventing severe influenza illness during the 2019-20 US respiratory virus season was highest in young adults (60 per cent), relatively low in middle-aged adults (20 per cent) and modest or negligible in the elderly.
High-dose vaccines improve effectiveness to 30 per cent in the elderly. Therefore, people 65 years of age or older should receive a high-dose quadrivalent vaccine.
Flu shots should be complemented by other infection control precautions including social distancing, indoor masking and frequent handwashing.
Do I really need a flu shot? You can get a flu shot concurrently with a COVID-19 shot.
Influenza vaccines are considered safe and effective in virtually all individuals, despite the lack of robust evidence of protection in very young children and the elderly.
Their use is akin to protection from wearing seatbelts; you may not necessarily be involved in an accident but if you are, the chances of survival and protection from serious injury are higher with their use than without.
During the 2019-20 respiratory virus season in the US, influenza vaccination prevented over 100,000 hospitalisations and over 6,000 deaths.
Given the expected burden of influenza illness and the ongoing COVID-19 pandemic, the benefits of vaccination will likely be greater during the current respiratory viral season compared to those in the past few years.
What is the role of COVID-19 boosters? Orange masses studded with small green dots.
For COVID-19, the effectiveness of a two-dose primary vaccine series plus a single booster in preventing hospitalisation is close to 90 per cent but gradually drops to around 65 per cent over the course of four to five months after the last vaccine dose.
Bivalent vaccine boosters may serve as a means of preserving vaccine-induced immunity against newer variants of SARS-CoV-2.
COVID-19 vaccines remain part of an effective strategy to counter the next wave of infection.
The latest bivalent vaccines manufactured by Pfizer and Moderna are recommended as boosters for individuals with at least two primary COVID-19 vaccinations.
The bivalent vaccines are believed to be more effective against the dominant BA.4 and BA.5 Omicron subvariants of SARS-CoV-2 than the original mRNA vaccines, but equal in effectiveness to first-generation bivalent vaccines that target the original strain and the BA.1 Omicron subvariant.
The US, Canada and Europe have slightly different age-based and time-based eligibility criteria for these boosters.
Influenza and COVID-19 are expected to make headway during the current respiratory virus season in northern climates.
Vaccination in conjunction with personal protective measures are the best means of staying healthy. (The Conversation) PY PY
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)
The Canadian government says it will donate up to 200,000 vaccine doses to fight the mpox outbreak in Congo and other African countries.
It says the donated doses of Imvamune will come from Canada’s existing supply and will not affect the country’s preparedness for mpox cases in this country.
Minister of Health Mark Holland says the donation “will help to protect those in the most affected regions of Africa and will help prevent further spread of the virus.”
Dr. Madhukar Pai, Canada research chair in epidemiology and global health, says although the donation is welcome, it is a very small portion of the estimated 10 million vaccine doses needed to control the outbreak.
Vaccine donations from wealthier countries have only recently started arriving in Africa, almost a month after the World Health Organization declared the mpox outbreak a public health emergency of international concern.
A few days after the declaration in August, Global Affairs Canada announced a contribution of $1 million for mpox surveillance, diagnostic tools, research and community awareness in Africa.
On Thursday, the Africa Centres for Disease Control and Prevention said mpox is still on the rise and that testing rates are “insufficient” across the continent.
Jason Kindrachuk, Canada research chair in emerging viruses at the University of Manitoba, said donating vaccines, in addition to supporting surveillance and diagnostic tests, is “massively important.”
But Kindrachuk, who has worked on the ground in Congo during the epidemic, also said that the international response to the mpox outbreak is “better late than never (but) better never late.”
“It would have been fantastic for us globally to not be in this position by having provided doses a much, much longer time prior than when we are,” he said, noting that the outbreak of clade I mpox in Congo started in early 2023.
Clade II mpox, endemic in regions of West Africa, came to the world’s attention even earlier — in 2022 — as that strain of virus spread to other countries, including Canada.
Two doses are recommended for mpox vaccination, so the donation may only benefit 100,000 people, Pai said.
Pai questioned whether Canada is contributing enough, as the federal government hasn’t said what percentage of its mpox vaccine stockpile it is donating.
“Small donations are simply not going to help end this crisis. We need to show greater solidarity and support,” he said in an email.
“That is the biggest lesson from the COVID-19 pandemic — our collective safety is tied with that of other nations.”
This report by The Canadian Press was first published Sept. 13, 2024.
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
HALIFAX – The Nova Scotia government says it could be months before it reveals how many people are on the wait-list for a family doctor.
The head of the province’s health authority told reporters Wednesday that the government won’t release updated data until the 160,000 people who were on the wait-list in June are contacted to verify whether they still need primary care.
Karen Oldfield said Nova Scotia Health is working on validating the primary care wait-list data before posting new numbers, and that work may take a matter of months. The most recent public wait-list figures are from June 1, when 160,234 people, or about 16 per cent of the population, were on it.
“It’s going to take time to make 160,000 calls,” Oldfield said. “We are not talking weeks, we are talking months.”
The interim CEO and president of Nova Scotia Health said people on the list are being asked where they live, whether they still need a family doctor, and to give an update on their health.
A spokesperson with the province’s Health Department says the government and its health authority are “working hard” to turn the wait-list registry into a useful tool, adding that the data will be shared once it is validated.
Nova Scotia’s NDP are calling on Premier Tim Houston to immediately release statistics on how many people are looking for a family doctor. On Tuesday, the NDP introduced a bill that would require the health minister to make the number public every month.
“It is unacceptable for the list to be more than three months out of date,” NDP Leader Claudia Chender said Tuesday.
Chender said releasing this data regularly is vital so Nova Scotians can track the government’s progress on its main 2021 campaign promise: fixing health care.
The number of people in need of a family doctor has more than doubled between the 2021 summer election campaign and June 2024. Since September 2021 about 300 doctors have been added to the provincial health system, the Health Department said.
“We’ll know if Tim Houston is keeping his 2021 election promise to fix health care when Nova Scotians are attached to primary care,” Chender said.
This report by The Canadian Press was first published Sept. 11, 2024.
ST. JOHN’S, N.L. – Newfoundland and Labrador‘s chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
Dr. Janice Fitzgerald says that so far this year, the province has recorded 230 confirmed cases of the vaccine-preventable respiratory tract infection, also known as pertussis.
Late last month, Quebec reported more than 11,000 cases during the same time period, while Ontario counted 470 cases, well above the five-year average of 98. In Quebec, the majority of patients are between the ages of 10 and 14.
Meanwhile, New Brunswick has declared a whooping cough outbreak across the province. A total of 141 cases were reported by last month, exceeding the five-year average of 34.
The disease can lead to severe complications among vulnerable populations including infants, who are at the highest risk of suffering from complications like pneumonia and seizures. Symptoms may start with a runny nose, mild fever and cough, then progress to severe coughing accompanied by a distinctive “whooping” sound during inhalation.
“The public, especially pregnant people and those in close contact with infants, are encouraged to be aware of symptoms related to pertussis and to ensure vaccinations are up to date,” Newfoundland and Labrador’s Health Department said in a statement.
Whooping cough can be treated with antibiotics, but vaccination is the most effective way to control the spread of the disease. As a result, the province has expanded immunization efforts this school year. While booster doses are already offered in Grade 9, the vaccine is now being offered to Grade 8 students as well.
Public health officials say whooping cough is a cyclical disease that increases every two to five or six years.
Meanwhile, New Brunswick’s acting chief medical officer of health expects the current case count to get worse before tapering off.
A rise in whooping cough cases has also been reported in the United States and elsewhere. The Pan American Health Organization issued an alert in July encouraging countries to ramp up their surveillance and vaccination coverage.
This report by The Canadian Press was first published Sept. 10, 2024.
