Whooping cough is caused by Bordetella pertussis bacteria, which infect the respiratory tract. The bacteria 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 spreads easily among people who are in close contact, especially between family members. It can occur at any time of year.
In general, a person with whooping cough can spread the disease from the time they develop symptoms to three weeks after coughing begins. If antibiotics are used, the contagious period can be shortened.
Symptoms begin six to 20 days after someone becomes infected. The illness usually starts with common cold-like symptoms, such as a runny nose, mild fever and cough. The cough often turns into a series of severe coughing spells, which can continue for six to 12 weeks. The disease gets its name from the whooping sound children often make as they try to catch their breath after coughing. The whooping sound may not occur in older children and adults.
Whooping cough can affect people of any age. However, the disease is usually much worse for babies. This is because the lungs of an infant are not fully mature. A baby under the age of 12 months can be more seriously affected by whooping cough, and is more likely to have complications 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 infants per year. These infants usually have not been immunized, or have not received the right number of vaccine doses for their age.
In older children, teens and adults, the disease is less serious and complications are rare. They may have whooping cough without realizing it. The only sign of infection may be a persistent cough lasting more than a week. Since whooping cough is often not diagnosed in older age groups, they can be the sources of infection for younger children.
Immunization with pertussis vaccine is the best way to protect babies against whooping cough. It is important to immunize infants without delay, starting at two months of age. Pertussis vaccine is given 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. Parents and caregivers must also be up to date with their immunizations. Protecting the mother and father from whooping cough helps prevent illness before the infant is fully immunized.
Before the pertussis vaccine was introduced in the 1940s, whooping cough was a major cause of serious illness and death among infants and young children. However, it has declined dramatically since a widespread pertussis immunization program was introduced in Canada. All Canadian residents can be immunized for free, as part of the publicly funded routine immunization schedule. Pertussis vaccine is given as an injection in combination with other routine vaccines.
Once, an older version of the pertussis (whole cell) vaccine was used only in children under seven years of age, since the severity of local reactions increased with age. The current (acellular) pertussis vaccine was introduced in Canada in the mid-1990s. It is very safe, and can be used in children, teens and adults.
Some people have swelling or tenderness at the injection site, while others develop a mild fever. The public health nurse can suggest ways to treat minor side effects following immunizations. 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 an immunized child does get whooping cough, the illness will be much milder thanks to protection from the pertussis vaccine.
Babies and children
This age group should have the vaccine at two, four, and six months of age. Booster doses should be given at 18 months, and between four to six years.
Teens and adults
Teenagers should get a single booster dose of vaccine containing pertussis in Grade 9, usually at 14 years of age, at school or at a public health centre.
Adults who did not receive a pertussis-containing vaccine in Grade 9 can now receive a dose of pertussis with their tetanus-diphtheria booster. The booster is normally given every 10 years.
Thanks to immunization, this serious disease can be reduced or eliminated. For more information about this and other vaccines, speak to your public health nurse or family doctor.
If you are a parent or caregiver, having a pertussis vaccine can help reduce the risk of illness in your children. If it has been more than 10 years since your last immunization, call your public health centre for an appointment to be immunized.
A single booster dose of vaccine-containing pertussis is offered to Grade 9 students in school-based immunization programs. If your child missed the program, call your public health centre to schedule immunization.
Even if your child has had whooping cough disease, complete the series of immunizations. Pertussis immunization is the best way to protect children from serious complications in case they become infected again.
Ask for a written immunization record. Keep it in a safe place at home where you can find it easily. If your child is exposed to anyone with whooping cough, check the record right away. Contact your local public health centre if the immunizations are not up to date.
See your health care provider if anyone in your household has a cough lasting longer than a week. Accurate diagnosis is important. Anyone with whooping cough should get antibiotic treatment and avoid close contact with babies and young children while still contagious.