Since the onset of the coronavirus outbreak, a vaccine has been widely regarded as the best path toward reopening society and returning to normalcy. Scientists have worked around-the-clock to develop a vaccine even entering late-stage human studies at record speed for the disease that has killed more than 430,000 people worldwide.
Yet, despite these Herculean efforts, scientists say a one-time cure-all is unlikely. Data on close cousins of the COVID-19 virus, including seasonal coronaviruses that cause the common cold, suggests the COVID-19 vaccine probably won’t offer lifelong protection — although more research is needed to understand how well and for how long a potential vaccine could work.
It’s a problem significant enough to worry Dr. Anthony Fauci, the head of the National Institute of Allergy and Infectious Diseases, who has been excited at the chance of developing a vaccine, but hesitant to predict how long it might work.
“When you look at the history of coronaviruses, the common coronaviruses that cause the common cold, the reports in the literature are that the durability of immunity that is protective ranges from three to six months to almost always less than a year,” Dr. Fauci said in an interview with JAMA Editor Howard Bauchner.
“That’s not a lot of durability and protection,” Fauci said.
And although it’s too soon to say how long a COVID-19 vaccine might protect you, an executive at AstraZeneca, one of the companies working to develop an effective vaccine, told a radio station that he thinks his vaccine might only offer protection for one year.
This means that if we get a safe and effective COVID-19 vaccine, it might not offer lifelong protection. Vaccine experts told ABC News it’s still too early to know for sure.
As scientists race to answer some of these questions, the United States government is forging ahead with Operation Warp Speed, an ambitious plan to have enough doses of a safe and effective vaccine to be able to vaccinate the majority of Americans by 2021.
“We cannot promise 100% chance of success,” a senior government official told reporters earlier this week. “What we can tell Americans is that we’ve taken every possible step to maximize the probability of success and shorten the timelines to getting safe, effective vaccines and therapeutics.”
One way to gauge the durability of an eventual vaccine could be to look at people who have already been infected with and survived COVID-19. But even though some people with COVID-19 have demonstrated an immune response to the disease and recovered, the longevity of response is still unknown, since scientists and doctors have known about the virus for less than six months.
Still, early studies have found that the immune response to SARS-CoV-2, the virus that causes COVID-19, is probably similar to SARS-CoV and MERS-CoV. And we know from SARS and MERS that immunity can last a few years, but antibody protection tends to wane about a year post-infection. This means that even people who have recovered from COVID-19 could get it again in the future.
Nevertheless, a COVID-19 vaccine could induce long-lasting immunity even if the infection does not, said Dr. Paul Goepfert, director of the University of Alabama at Birmingham Vaccine Research Clinic.
“Because vaccines are much more focused in their immune response, it could be that you could develop an antibody to the part of the virus that is more long-lasting,” Dr. Goepfert said.
It may come down to the structure and biology of this particular virus. SARS-CoV-2, the virus that causes COVID-19, is covered in tiny spikes called surface proteins. Experts say that the virus is unlikely to mutate in a meaningful way, meaning the vaccines that are being developed now are likely to work in the future.
Different vaccine developers are taking different approaches to create a COVID-19 vaccine. Some groups, such as Oxford and its partner AstraZeneca, are using a traditional approach of using the virus itself but neutering it so that it doesn’t make people sick.
Others, such as Moderna and Pfizer, are hoping that by coaxing the body to create this protein, they might be able to trick the immune system into mounting an effective response against future infection. They’re hopeful that their approach will allow them to be more agile should the virus mutate in the future.
Aside from durability, not all vaccines have complete protection, for example, the annual flu shot ranges in effectiveness and works better for children than for the rest of the population. In 2019, it was less than 50% effective in preventing the flu, but there were still major benefits.
“A 60% effective COVID vaccine would still decrease the number of infections, the number of deaths and the number of people who become severely ill,” Goepfert said.
“Obviously, a vaccine that works 100% of the time would be ideal, but that is not realistic,” said Dr. John Mascola, director of the National Institutes of Health Vaccine Research Center.
It’s possible that, like the flu vaccine, an eventual coronavirus vaccine might also work better for certain groups, although right now experts say it’s too soon to tell.
Should scientists develop a safe and effective vaccine — and they are cautiously optimistic that they will — it would be the safest approach to achieving herd immunity. Epidemiologists estimate that about 60% to 80% of the U.S. population would have to recover from COVID-19 or have the antibodies from a vaccine to stop the virus from spreading widely.
The reality is that a coronavirus vaccine may provide relatively short protection, said Dr. Beth Kirkpatrick, chair of the University of Vermont’s Department of Microbiology and Molecular Genetics.
Researchers may have to consider booster shots or revaccination if people’s antibodies fall below the amount associated with protection — a count that is still unknown. Only time will tell, and long-term observation of patients after vaccination will determine how durable the vaccine really is.
“We will have to follow those people for quite a long period of time to be able to know how long it’s going to last for, because if it starts fading away, it won’t be until a year or two years or three years that we’ll start seeing the infections pop up in people that got vaccinated,” Kirkpatrick said.
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.
