Suspected cases must be reported immediately by phone to the Thunder Bay District Health Unit at 625-8318 or toll-free 1-888-294-6630, ext. 8318 (Monday-Friday, 8:30am to 4:30pm). After hours and on weekends/holidays call Thunder Bay Answering Service at (807) 624-1280.
The measles virus is a member of the genus Morbillivirus of the family Paramyxoviridae.
Symptoms of measles begin 7 to 18 days after exposure to a case of measles and include fever, runny nose, cough, drowsiness, irritability and red eyes (conjunctivitis). Small white spots (known as "Koplik’s spots") appear on the inside of the mouth and throat. Then, 3 to 7 days after the start of the symptoms a red, blotchy (maculopapular) rash appears on the face and then progresses down the body. Complications include diarrhea, respiratory problems, pneumonia, otitis media and encephalitis.
Modes of transmission:
The virus is highly contagious and is spread by airborne droplet nuclei, close personal contact or direct contact with the respiratory secretions of a case.. Transmission can occur as a result of the persistence of the virus in the air or on environmental surfaces. Measles virus can remain active and contagious in the air or on infected surfaces for at least two hours. Measles is one of the most highly communicable infectious diseases.
About 10 days, but may be 7-18 days from exposure to onset of fever, usually 14 days until rash appears; rarely as long as 19-21 days.
Period of Communicability:
One day before the start of prodromal period, which is usually about 4 days before rash onset, to 4 days after the onset of rash.
- Contact with case
- Not immunized or partially immunized
After infection, immunity is generally lifelong. The following individuals should be considered susceptible: lack of documented evidence of vaccination with measles-containing vaccine (age dependent) or lack of laboratory evidence of prior measles infection or immunity.
Diagnosis & Laboratory Testing
Lab confirmation of infection with clinically compatible signs and symptoms in the absence of recent immunization with measles-containing vaccine. Clinically compatible signs and symptoms are characterized by all of the following:
fever >38.3 degrees Celsius (oral) and cough, coryza or conjunctivitis followed by generalized maculopapular rash for at least three days.
Laboratory diagnosis of measles should include both diagnostic serology and virus detection. See Labstract for more details.
Treatment & Case Management
There is no specific treatment for persons with measles infection; however severe complications can be avoided through supportive care that ensures good nutrition and adequate fluid intake. Individuals diagnosed with measles should be advised to stay home for 4 days after the appearance of the rash.. Self-isolation will help to prevent further transmission of the virus..
A measles contact is any susceptible person who shared the same air space for any length of time during the period of communicability, including two hours after the case left the air space (e.g. home, school, day care, school bus, doctor’s office, emergency room, etc.). .
The timely administration of MMR vaccine or immune globulin (Ig) can be used to reduce the risk of infection in susceptible individuals exposed to measles. Post-exposure prophylaxis (PEP) is not 100% effective and contacts who receive PEP should be counseled on the signs and symptoms of measles and to avoid contact with high risk individuals.
Immunization with MMR vaccine of immunocompetent susceptible contacts over 6 months of age within 72 hours after exposure may prevent measles infection. Susceptible individuals with a medical contraindication to MMR vaccine (infants under 6 months of age, pregnant women, and immunocompromised individuals) who are within 6 days of exposure should be offered Ig at the recommended dose. Certain immunocompromised individuals should also be considered to receive Ig for PEP regardless of their past vaccination status.
Staff from the Thunder Bay District Health Unit will be involved with contact identification and tracing, assessing susceptibility, PEP information, and exclusion decisions.
1. Public Health Ontario. "Defending Ontario against Measles." (includes resources and testing information)