Individuals who have or may have pertussis shall be reported to the local Health Unit.
Pertussis is caused by, a Gram-negative, bacillus, Bordetella pertussis, (B. pertussis).
The clinical course of pertussis is divided into three stages:
- Catarrhal Stage – mild upper respiratory tract symptoms with a mild occasional cough that lasts about 1–2 weeks
- Paroxysmal Stage – increase in the severity and frequency of the cough; paroxysms are characterized by repeated violent coughs possibly with a high pitched inspiratory whoop commonly followed by vomiting and can last 1–2 months; fever is absent or minimal
- Convalescent Stage – gradual recovery period which can take weeks to months
The clinical course varies with age. In young infants, who are at the highest risk, clinical symptoms are frequently atypical and it is this group who has the most serious complications. Pertussis presentation may also be atypical in adults or among persons previously immunized.
Modes of Transmission
Direct contact with discharges from respiratory secretions of infected persons via droplets.
Usually 9–10 days, can range from 6–20 days.
Period of Communicability
Highly communicable in the early catarrhal stage and beginning of the paroxysmal stage (first 2 weeks) and then decreases and becomes negligible in about 3 weeks.
No longer communicable after 5 days of effective treatment.
Non-immunized or partially immunized individuals are susceptible to pertussis. Previously immunized adolescents and adults (due to waning immunity) may also be susceptible. Infection does not induce long term immunity. Secondary attack rates can occur, of up to 90% in non-immune household contacts.
Diagnosis and Laboratory Testing
Consider Pertussis in an individual with a paroxysmal cough or a cough lasting 2 weeks or more. A nasopharyngeal (NP) swab specific for Bordetella pertussis, must be used to collect a specimen. A Bordetella Collection Kit can be ordered from Public Health Ontario.
Treatment and Case Management
Advise cases to avoid contact with young children, infants, and women in their 3rd trimester of pregnancy until the completion of 5 days of treatment or 21 days post cough onset. Advise symptomatic individuals to remain at home until they are well.
Refer to the current Publicly Funded Immunization Schedules for Ontario for more information on adult immunization. Tdap can be safely administered regardless of the interval from the last tetanus-diphtheria booster.
Contacts: Antibiotic chemoprophylaxis is only recommended for the following contacts of a confirmed pertussis case:
- Household contacts (including attendees at family day care centers) where there is an infant < 1 year of age (vaccinated or not) or a pregnant woman in the third trimester.
- For out of household exposures, infants less than one year of age regardless of immunization status and pregnant women in their third trimester who have had face-to-face exposure and/or have shared confined air for > 1 hour.
Chemoprophylaxis should be implemented as soon as possible after exposure as efficacy is related to early implementation. It is not likely to be beneficial after 21 days since the first contact.
Contacts who meet the definition above will be contacted by Public Health staff.