The largest whooping cough outbreak to ever hit New Brunswick is over, health officials announced on Wednesday.

"Reported cases of whooping cough have diminished greatly in the past weeks," Dr. Eilish Cleary, the province's chief medical officer of health, stated in a release.

She credited the decline, in part, to a province-wide immunization program launched last year.

Students in grades six, seven and eight in the east and south regions were vaccinated against the highly-contagious bacterial infection in the spring, while students in grades seven, eight and nine in the rest of the province were immunized in the fall.

'Immunization offers the best protection against the disease or another outbreak.'—Dr. Eilish Cleary, chief medical officer of health

"Immunization offers the best protection against the disease or another outbreak," Cleary said.

A total of 1,421 cases of whooping cough, also known as pertussis, were reported across the province last year.

Children between the ages of 10 and 14 represented the bulk of the cases, followed by children between the ages of five and nine, and infants.

About 40 per cent of the cases were in Moncton, 11 per cent in Fredericton and the rest were in the northern part of the province, officials had said at the time.

Ensure vaccines up-to-date

Cleary is reminding New Brunswickers about the importance of ensuring they are up-to-date with the province's routine immunization schedule.

A child under six years needs five doses of the pertussis vaccine, starting at two months of age, to be fully immunized. An additional booster dose, combined with tetanus and diphtheria (Tdap) vaccine, is given routinely to adolescents between 14 to 16 years of age across Canada.

It is recommended that adults not previously immunized against pertussis receive one dose of the Tdap vaccine.

Whooping cough is a disease of the lining of the respiratory tract caused by the Bordetella Pertussis bacterium.

Symptoms usually start five to 21 days after someone has been exposed and can include cold-like symptoms, such as sneezing, runny nose, low-grade fever and a mild cough that worsens with coughing spells that often end with a "whoop" sound.

Whooping cough is easily transmitted from person to person, mainly through droplets from the nose, mouth and throat of an infected person.

It can affect any age, but is most dangerous in babies and pregnant women in their third trimester.

Basic hygiene measures, such as regular hand-washing, disposing of tissues properly and containing coughs and sneezes also help control the spread of whooping cough.

Outbreaks usually occur every three to five years, health officials have said. The previous one in New Brunswick was in 2004.