Ottawa, Dec 28 (IANS): Cases of whooping cough, also known as pertussis or the 100-day cough, are increasing in several provinces and territories in Canada, local media reported.

Canadian health officials have reported 19,000 cases of pertussis so far this year and the country typically sees 1,000 to 3,000 cases a year, CTV News reported.

Whooping cough was mentioned by Dr. Theresa Tam, Canada's chief public health officer, on her biggest health concerns heading into 2025.

Tam said that whooping cough was controlled by vaccination for years and that one of the reasons it may be coming back is the pandemic's disruption on routine childhood vaccinations, Xinhua news agency reported.

Whooping cough is considered a 'nationally notifiable disease' in Canada and it's monitored through the Canadian Notifiable Disease Surveillance System, which has been set up to keep track of transmission of infectious diseases, CTV News reported.

Whooping cough is a highly contagious respiratory tract infection. In many people, it's marked by a severe hacking cough followed by a high-pitched intake of breath that sounds like 'whoop.'

Before the vaccine was developed, whooping cough was considered a childhood disease. Now whooping cough primarily affects children too young to have completed the full course of vaccinations and teenagers and adults whose immunity has faded.

Deaths associated with whooping cough are rare but most commonly occur in infants. That's why it's so important for pregnant women — and other people who will have close contact with an infant — to be vaccinated against whooping cough.

Once you become infected with whooping cough, it takes about seven to 10 days for signs and symptoms to appear, though it can sometimes take longer. They're usually mild at first and resemble those of a common cold:

After a week or two, signs and symptoms worsen. Thick mucus accumulates inside your airways, causing uncontrollable coughing.

However, many people don't develop the characteristic whoop. Sometimes, a persistent hacking cough is the only sign that an adolescent or adult has whooping cough.