Pertussis

Overview

Whooping cough, or pertussis, is a highly contagious infection of the respiratory tract. The incidence of whooping cough declined dramatically after widespread immunization with pertussis vaccine started in Canada in the 1940s. Over the past decade, however, the number of reported cases has begun to climb, especially among older children and young adults. This is because the vaccine that was used prior to the mid-nineties fades over time.

Symptoms

Whooping cough may start with common cold-like symptoms, such as a runny nose, mild fever and cough, but it often turns into a series of severe coughing spells that can continue over a period ranging from six to 12 weeks. The disease gets its common name from the "whoop" sound people often make as they try to catch their breath after one of these coughing spells.

Some of the complications for infants can include vomiting after a coughing spell, weight loss, breathing problems, choking spells, pneumonia, convulsions, brain damage, and in rare cases, death. In older children and adults, the disease is less serious, although in rare cases the severe coughing can cause vomiting or a hernia or even break a rib. Many, however, have no recognizable symptoms, or only those symptoms that mimic a cold. As a result whooping cough can go undetected and spread easily to younger children and infants in the home who are unvaccinated, or under-vaccinated.

Causes

Whooping cough is caused by a bacterium called Bordetella pertussis, which infects the respiratory tract. It is highly contagious as the bacteria spreads through droplets in the air when an infected person coughs or sneezes. You can also become infected through direct contact with discharges from the nose or throat of an infected person.

Treatment

Once your doctor has confirmed pertussis, it can be treated with antibiotics such as erythromycin. You must always finish all of the medicine that is prescribed, even if your symptoms go away first.

Because coughing spells can cause vomiting, you must ensure that your child doesn't becoming dehydrated or weak because of a lack of nutrients. Provide them with frequent small meals and plenty of water and other liquids.

If your child is under 6 months old, he or she may be hospitalized because of the possibility of complications such as pneumonia.

Prevention

The current whooping cough vaccine is safer and more effective than the old vaccine. Many children have some swelling or tenderness at the spot where the vaccine is injected, and some may also develop a mild fever, but these reactions are minor and temporary. Serious side effects are extremely rare, and the benefits of the vaccine far outweigh the slight risk of a serious adverse reaction. The vaccine used in Canada prevents the disease about 85% of the time. If a vaccinated child does get whooping cough infection, the health effects will be far less severe due to protection from the vaccine.

The vaccine to protect against whooping cough is provided free to all young children in Ontario as part of the publicly funded routine immunization schedule. It is usually given by a needle "shot" in combination with other childhood vaccines. To be fully immunized, a child needs five doses of whooping cough vaccine, starting at two months of age. Talk to your health care provider to make sure your child gets the complete series of shots on schedule.

In Ontario, teens between the age of 14 and 16 can now get a free booster shot against whooping cough as it has been added to the shot they previously were given for diphtheria and tetanus. Since adolescents and adults may carry the bacteria, experts say the new vaccine should help build a ·wall of protection' in the future by preventing the transmission of the disease to vulnerable infants.

Click here for a chart that outlines the schedule for publicly funded vaccines in Ontario available for children beginning their routine immunization in early infancy.

Additional Resources:

The Canadian Paediatric Society

Canadian Immunization Awareness Program

The National Influenza Immunization Campaign

Health Canada, Immunization Division