Holiday masking recommended amid spike in whooping cough cases
831 cases confirmed in N.B., most involving children and youth, says acting chief medical officer of health
New Brunswick's acting chief medical officer of health is encouraging people to mask during holiday gatherings as the province-wide whooping cough outbreak has spiked to more than 800 cases and other viruses, such as COVID-19, the flu and RSV spread.
A total of 831 whooping cough cases have now been confirmed, Dr. Yves Léger said Tuesday.
That's a 489 per cent increase since the outbreak was declared in August.
It's the most cases New Brunswick has seen in 12 years, when the last provincial outbreak was declared, he said. The 2012 outbreak was the province's largest ever, with 1,421 confirmed cases. It lasted a year.
"There are some signs that we may start to see some improvements," said Léger, noting the numbers have "sort of stabilized."
But "that's really preliminary and the holiday season may affect that," he said.
"Certainly, we may see a slight increase in cases after the holidays as well."
Infants most at risk
Whooping cough, or pertussis, is a highly contagious respiratory infection that is easily transmitted, mainly through droplets from the nose, mouth and throat of an infected person.
It begins with cold-like symptoms and a mild cough that gets worse and often ends with a "whooping" sound. The disease is also known as the "100-day cough."
"What concerns us the most when we have pertussis activity and outbreaks is the risk that this poses to newborns and young infants, especially those that are too young to get their first doses of pertussis vaccine," Léger said.
"For those young children, pertussis is usually actually quite severe and can sometimes be fatal."
So far, no deaths have been reported and only four hospitalizations, said Léger, none of which required intensive care. "We've been very fortunate."
Annual average of 38 cases
Pre-COVID, in 2019, New Brunswick had a total of 83 whooping cough cases, according to the Department of Health. Last year, there were fewer than five.
The annual average over the past five years has been 38.1
- 2019 — 83
- 2020 — 100
- 2021 — Fewer than five
- 2022 — Seven
- 2023 — Fewer than five
But Public Health was expecting an increase because the disease is cyclical in nature, said Léger. It usually rears its head every five to seven years.
The outbreak began on the Acadian Peninsula in June, with 11 cases, but expanded to the entire province in August, when there were 141 cases, with at least one in each of the seven health zones.
As of Tuesday, nearly 65 per cent of the cases have been in the Moncton region, Zone 1, said Léger. The Bathurst region, Zone 6, accounts for about 14 per cent, and the Edmundston region, Zone 4, 10 per cent, he said. The other regions each have about 10 per cent or less, Léger said.
Young represent 60% of cases
Children and youth have been the hardest-hit, representing about 60 per cent of all cases, he said.
Children aged 10 to 14 represent the majority, at nearly 33 per cent, followed by those 15 to 19 years old, at 14 per cent, according to Department of Health spokesperson Tara Chislett. Children five to nine years old account for 13 per cent.
She did not provide any data for those under five.
Vaccination rates just under 80%
Léger said he doesn't believe a decrease in vaccination rates is driving the outbreak.
"The number or the percentage of kids that are up to date on their pertussis vaccine is just under 80 per cent, both for school entry as well as the Grade 7 booster," he said. "And that, according to the data we have, does not seem to have significantly changed in recent years or from our pre-pandemic time period as well."
The Department of Health's 2023-24 school immunization report shows that among kindergarten students with proof of immunization, 77.4 per cent were up to date on their diphtheria, tetanus, pertussis (DTap) vaccine, down from 78.5 per cent the previous year.
Among Grade 7 students, the vaccination rate is 78.4 per cent, down from 82.6 per cent in 2022-23, and 83 per cent the previous year, the report shows.
The national immunization target is 95 per cent by 2025 to provide so-called herd immunity, where there's enough community resistance to a disease that it's unlikely to spread.
During the previous outbreak, the province launched special school-based immunization clinics for students in grades 6, 7 and 8 in the most affected areas, Zone 1, the Moncton region, and Zone 2, the Saint John region.
COVID-19 precautions recommended
For the current outbreak, Léger recommends people go back to some of the practices they learned during the COVID-19 pandemic to reduce their risk of infection.
That includes staying up-to-date on vaccinations, and frequent handwashing, especially before eating, he said.
"And I think considering wearing a mask again, right? This really should be, I think, a seasonal thing like when we talk about our flu and our COVID vaccines in the fall.
"Considering wearing a mask is important, especially if we're going out in public, especially in small or crowded spaces or where there may be poor ventilation, it's good to consider having our mask and considering wearing it."
COVID-19 cases have started to decrease, but there's still "a lot" of the virus circulating, said Léger. Meanwhile, influenza and respiratory syncytial virus, or RSV, are both increasing, he said.
If people are sick, they should stay home, if possible, even if their symptoms are mild, said Léger.
If they can't stay home, they should take measures to prevent infecting others, including avoiding contact with anyone who is high-risk or has underlying medical conditions, he said.
People who are hosting events can help keep their guests safe by having hand sanitizer and extra masks available, Léger said. They can also improve the ventilation in their home by increasing the air exchange or opening some windows for a cross breeze, he said.
Steps being taken to control outbreak
Public Health has also undertaken a "number of activities" to try to get the whooping cough outbreak under control, said Léger.
"We're communicating regularly with the public to provide updates on the outbreak status and the activity," he said.
Although the last news release was issued four months ago, Léger said Public Health's advisories and alerts website is being updated.
The department spokesperson did not respond to questions about when whooping cough was added to the site, but as recently as Dec. 8, measles was the only outbreak listed.
Public Health is also communicating with health-care providers to make sure they're aware of the increased activity and to provide them with recommendations on what they can do to improve immunization rates among their patients, Léger said.
In addition, officials are working with health-care providers and other prenatal care providers to educate parents on what they can do to keep their newborns safe, and encouraging pregnant women to get a shot, as that immunity is passed on to their newborns, he said.
To improve access to whooping cough vaccines for those 18 or older and pregnant women, pharmacists who are already authorized to give injections can now administer the whooping cough vaccine.