A whooping cough immunization campaign continues in New Brunswick this fall in response to an ongoing outbreak of the highly contagious bacterial infection across the province.

All students in grades seven, eight and nine will be vaccinated at their schools, said Dr. Eilish Cleary, the province's chief medical officer of health.

There are currently more than 1,100 confirmed cases of whooping cough in New Brunswick, said Cleary.

About 40 per cent of the cases are in Moncton, while Fredericton has about 11 per cent, and the rest are in the northern part of the province, she said.

"Since immunization offers the best protection against the disease and the majority of cases are occurring in the 10- to 14-year-old group, public health nurses will visit schools around the province to provide immunizations to all students in grades 7, 8 and 9," Cleary said in a statement.

The immunization campaign started at the end of the last school year, when nearly 12,000 students in grades 6, 7 and 8 in Moncton and Saint John were vaccinated.

At that time, there were about 370 cases, primarily in those two cities, said Cleary.

Normally, New Brunswick only has about 40 cases of whopping cough each year.

Easily spread

Whooping cough is a disease of the lining of the respiratory tract that resembles a common cold except for the prolonged coughing.

It is easily spread from person to person, mainly through droplets in the air from an infected person’s coughs or sneezes. It can also be spread through coming in contact with discharges from an infected person’s nose or throat.

Symptoms include sneezing, runny nose, low grade fever and coughing that often ends with a whooping sound before the next breath.

The symptoms usually start five to 21 days after someone has been exposed. Patients are most contagious during the first two weeks, but may last up to three weeks.

Whooping cough can affect people of any age, but is most severe among young infants.

Many adults develop the infection and pass it along to children.

Immunization intervals under review

The routine immunization schedule in New Brunswick recommends that children be immunized against whooping cough at two, four, six and 18 months; between the ages of four and six; one dose during adolescence; and one booster as an adult.

But the number of cases of whooping cough in school-age children, adolescents and adults may suggest waning immunity, according to public health officials.

The intervals between recommended doses are currently being reviewed.

Meanwhile, those who have not been vaccinated during the last five years and are in close, regular contact with children younger than one year of age are encouraged to contact their usual immunization provider and arrange for the vaccine to be administered, said Cleary.

Adults who have received immunization with a whooping cough-containing vaccine as an adult need not be immunized again. A wave of whooping cough usually occurs every three to five years, officials have said.

Immunization can help prevent a spike in the infection.

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.