Whooping cough can infect the respiratory tract any time of year. It is caused by Bordetella pertussis bacteria, which spread through droplets in the air when an infected person coughs or sneezes. Direct contact with infected fluid from someone’s nose or throat can also transmit the disease.
Whooping cough easily spreads among family members, in schools, and anywhere people are in close contact.
In general, a person stays infectious from the beginning of infection to three weeks after coughing begins. If antibiotics are used, the period of infectiousness lasts only five days after the start of treatment.
Although anyone can get whooping cough, even more than once, the effects are usually much worse for babies. Older members of a household may have whooping cough without realizing it. This can pose serious risks to younger children and babies who are not vaccinated or have not received enough vaccine.
Symptoms begin six to 20 days after someone becomes infected. It may start with common cold-like symptoms, including a runny nose, mild fever, and cough, but often turns into a series of severe coughing spells that can continue from six to 12 weeks. The disease gets its name from the whooping sound people often make as they try to catch their breath after a coughing spell.
A baby under the age of 12 months can be more seriously affected by and likely to have complications from whooping cough than those in other age groups. Complications for babies can include vomiting after a coughing spell, weight loss, breathing problems, choking spells, pneumonia, convulsions, brain damage, and, in rare cases, death. Currently in Canada, whooping cough kills one to three babies per year, usually those who are not vaccinated or have not received enough vaccine.
In older children, teens and adults, the disease is less serious and complications are rare. The only sign of infection may be a persistent cough lasting more than a week. Since it is often not diagnosed in older age groups, they can be sources of infection for younger children.
The best way to protect your baby against whooping cough is to immunize with the pertussis vaccine at two, four and six months of age. Booster doses should be given at 18 months and between four and six years of age, the preschool years. It is important that young babies start their pertussis vaccination without delay at two months of age.
You can also help keep your baby healthy by avoiding contact with those who are sick. Anyone of any age who has a cough or cold symptoms should stay away from young babies.
Before the pertussis vaccine was introduced in the ‘40s, whooping cough was a major cause of serious illness and death among babies and young children. However, it has declined dramatically since a widespread pertussis immunization program was introduced in Canada. All Canadian residents can be vaccinated for free, as part of the publicly funded routine immunization schedule. It is usually given as a needle shot in combination with other routine vaccines.
The number of Canadian teens and adults diagnosed with whooping cough has been rising since the early ‘90s. This may be partly due to the fact that protection provided by the older (whole cell) pertussis vaccine tends to fade over time. However, even with the recent increase in reported cases, there are far fewer cases of whooping cough than they once were.
The older version of the pertussis vaccine was used in children under the age of seven until the mid-‘90s. Then, the current (acellular) pertussis vaccine was introduced in Canada. It is very safe, and licensed for use in children, teens and adults. Almost anyone can take it, apart from those who had trouble breathing or severe swelling of the skin or mouth when they received it earlier.
Some people may have swelling or tenderness at the injection site, while others may develop a mild fever. These reactions are minor and temporary, and serious side effects are extremely rare. The benefits of the vaccine far outweigh the slight risk of a reaction. If a vaccinated child does get whooping cough, the effect will be much milder thanks to protection from the pertussis vaccine.
Parents are urged to make sure their children complete all the current pertussis vaccine doses on time starting at two, four, and six months of age, with booster doses at 18 months and four and six years of age.
The older pertussis vaccine was only used in children under age seven, since the severity of local reactions increased with age. However, the current vaccine is safe for teens and adults.
Any teenager who has not received the current pertussis vaccine should get a single booster dose in a school-based program or from a health care provider, usually at 14 years of age. The same is recommended for adults who have not received it. In addition to directly protecting teens and adults, pertussis immunization helps keep babies safe too.
Thanks to immunization, we have the ability to reduce or eliminate this serious disease. For more information about this and other vaccines, speak to your family doctor or a public health nurse.