Public Health Agency of Canada
Symbol of the Government of Canada

Share this page

Measles

Recent Notices

Measles is a highly infectious disease caused by the measles virus and is characterized by a red, blotchy rash that begins on the face. It is spread through direct contact with or inhalation of the secretions from an infected person's nose or mouth. Measles affects all age groups and can be prevented by a vaccine. The National Advisory Committee on Immunization (NACI) recommends immunization against measles.

About Measles

Agent of disease

Measles is caused by the measles virus, a member of the genus Morbillivirus of the family Paramyxoviridae.

Symptoms

Symptoms of measles begin 7 to 18 days after infection and include fever, runny nose, drowsiness, irritability and red eyes. Small white spots (known as "Koplik's spots") can appear on the inside of the mouth and throat. Then, 3 to 7 days after the start of the symptoms, a red, blotchy rash appears on the face and then progresses down the body. Complications include diarrhea, pneumonia and infections of the brain. In developed countries 1 to 2 cases per 1,000 result in death. This increases to 3 to 5 cases per 1,000 in developing countries.

Photos of Clinical Manifestations of Measles

Clinical Manifestations of MeaslesTypical red blotchy appearance of measles rash at its peak. The early signs of measles consist of a runny nose with fever, red and puffy eyes (indicating inflammation of the conjunctiva), cough and malaise. During this early stage, white or greyish spots, which look like small grains of sand with a reddish base also develop on the inner lining of the mouth; these Koplik spots are peculiar to measles.  Source:  Public Health Agency of Canada

Clinical Manifestations of MeaslesLike most children who have measles, this child looks ill and miserable. The rash appears as a fine, flat or slightly raised (macular or maculopapular) rash and becomes confluent as it progresses, giving it this red, blotchy appearance at its peak. In mild cases the rash tends not to be confluent while in severe cases the rash is more confluent and the skin may be completely covered.  Source:  Public Health Agency of Canada

Clinical Manifestations of MeaslesAppearance of measles rash in a dark-skinned child. The red, blotchy appearance of a measles rash is not apparent in darker people but the skin looks granular in the early stage. The slight desquamation or peeling of the skin which occurs as the rash clears can be seen on the face and upper body of this child.

Photo by courtesy of Dr. Adwoa Bentsi-Enchill.  Source:  Public Health Agency of Canada

Period of communicability

The incubation period for measles is about 10 days, but may be 7 to 18 days from exposure to onset of fever. The rash usually appears 14 days from exposure although it can seldom appear as late as 19 to 21 dates from exposure to the measles virus. Infectiousness begins from 1 day before the beginning of the prodromal period (usually about 4 days before rash onset) to 4 days after appearance of the rash.

How it is transmitted

The virus is transmitted by airborne droplets or direct contact with nasal or throat secretions of infected persons. Less commonly, the virus spreads through contact with articles freshly soiled with nasal and throat secretions.

Worldwide distribution

Measles occurs throughout the world and remains a serious and common disease in developing countries. According to the World Health Organization, measles is a leading cause of vaccine preventable deaths in children worldwide. The global goal was to reduce mortality due to measles by 90% by 2010 (compared with levels in 2000). This goal was not reached. By 2010, the global mortality of measles has been reduced by 74%, from 535,300 deaths in 2000 to 139,300 deaths.

Measles was eliminated in the WHO Region of the Americas in 2002 with the last endemic measles case occurring on November 16, 2002. Since that time, there have been small numbers of imported and import-related cases in the Americas: the annual count ranged from a low of 85 in 2005 to a high of 253 in 2010. These cases have resulted in limited secondary spread. However, in 2011, this region has reported the highest number of measles cases since the virus was eliminated, with the majority of these cases associated with a large outbreak in Quebec, Canada.

Outside of the Americas, measles activity remains high. As of October 2011, there were over 26,000 cases in the WHO European Region with the highest number reported in France (more than 14000 cases). There have been 11 measles-associated deaths in the Region. Large outbreaks have also occurred in Africa, mostly in the Democratic Republic of the Congo, with more than 106,000 cases and 1100 deaths.

Prevention and control

Measles can be prevented by immunization. Immunization of all children is recommended at 12 months of age as part of a combined vaccine containing measles, mumps and rubella (MMR); with a second dose at either 18 months or at 4 to 6 years of age. For further information about the MMR vaccine and its use in adolescents, adults and special populations, please refer to the most recent version of the Canadian Immunization Guide.

Any suspect measles cases, particularly those with travel history to areas with endemic or epidemic measles, should be reported as soon as possible through local public health. Patients should be isolated for 4 days after appearance of the rash. Searching for and immunizing exposed susceptible contacts can limit the spread of disease.

Epidemiology of Measles in Canada

Canada has made great progress in its goal of measles elimination, and endemic transmission of measles has been interrupted by high vaccine coverage as a part of routine infant and childhood immunization programs. There have been no indigenous cases of measles reported in Canada since 1997. However, imported cases continue to occur. Secondary spread from these imported cases has been self-limited and involves Canadians who are still vulnerable due to lack of immunizations or only partial immunization (i.e. only one dose of vaccine). The largest outbreaks have occurred in isolated groups that are philosophically opposed to immunization with very limited secondary transmission of measles in the general population. Between 2002 and 2010, a total of 327 confirmed cases of measles were reported in Canada, with an average of 11 cases annually except in 2007 (102 cases), 2008 (62 cases) and 2010 (99 cases). The high numbers of cases in those three years were mainly due to outbreaks in Quebec, Ontario and British Columbia respectively (please see Recent Outbreaks for more detailed information).

Before the introduction of the vaccine in 1963 to 1964, measles occurred in cycles with an increas­ing incidence every 2 to 3 years. At that time, an estimated 300,000 to 400,000 cases occurred annually. Since the introduction of vaccine, the incidence has declined considerably in Canada (see Figure 1). Between 1989 and 1995, in spite of very high vaccine coverage, there were many large outbreaks involving mainly children who had received one dose of the measles vaccine. It was estimated that 10% to 15% of immunized children remained unprotected after a single dose given at 12 months of age, a proportion large enough to allow circulation of the virus.

In 1996/97, every Canadian province and territory added a second dose of measles-containing vaccine to its routine immunization schedule, and most conducted catch-up programs in school-aged children with measles or measles/rubella vaccine. This intervention achieved vaccine coverage for the second dose in excess of 85%, reducing the proportion of vulnera­ble children to such a negligible level that viral transmission has not been sustained.

Figure 1. Number of cases and incidence rate (per 1,000,000 population), by year, 1924-2011, and year of vaccine introduction.

* In 1963, live vaccine was approved for use in Canada, followed by the approval of killed vaccine in 1964. The killed vaccine had limited availability, and use was discontinued by the end of 1970. A single dose schedule with the live vaccine was introduced into all provincial/territorial routine immunization programs by the early 1970s. The routine one-dose measles-mumps-rubella vaccine was introduced in 1983.

Note: Measles was not nationally notifiable between 1959 and 1968.

Figure 1 - Text Equivalent

Recent Outbreaks

Quebec experienced an epidemic of measles in 2011. A total of 725 confirmed cases were reported between January 8th and December 22nd, 2011. The first reported cases were primarily among travelers, who contracted the illness during a stay in Europe. Sustained local transmission began in April, first in a school and then in a community-based setting. The majority of cases (87%) were concentrated in two neighbouring regions. The epidemic mainly affected young people aged 10 to 19 years (66% of cases). Finally, the majority of cases (76%) were not considered protected against measles (0 doses, unknown vaccination history, or vaccinated without documentation), 19% were considered protected for their age and 5% had received one dose of measles containing vaccine.

In the spring of 2010, an outbreak in British Columbia resulted in 82 confirmed cases. Infants and children less than 5 years old were disproportionately affected, as were adults 30 to 39 years old. Where immunization status was known, 59% of cases had not been vaccinated, 29% had received one dose of measles containing vaccine and 12% had received two doses of measles containing vaccine.

In 2008, an outbreak in Ontario began in March and ended in June with a total of 53 confirmed cases. The source of the index case is unknown. About one third of the cases were less than in 10 years old. Where immunization status was known, nearly all cases (29 of 30) had not been vaccinated.

In 2007, an outbreak in Quebec began in April and ended in September with a total of 96 confirmed cases. Although the source of the index case is unknown, the laboratory results suggest that there were two separate importations. Over half (54.7%) of the cases were between the ages of 1 and 10 years. Where immunization status was known, nearly all cases (79 of 86) were in individuals who had not received 2 doses of measles containing vaccine.

Measles Surveillance in Canada

In Canada, surveillance data on measles are collected through three systems at the federal level: the Canadian Notifiable Disease Surveillance System (CNDSS), the Canadian Measles/Rubella Surveillance System (CMRSS), and the Measles and Rubella Surveillance (MARS) pilot.

Measles Data

The following two tables contain recent data on the number of confirmed cases and incidence of measles in Canada from 2005 to 2011. For further surveillance data, please see the Notifiable Diseases On-Line webpage, as well as the Publications section below.

Table 1. Confirmed cases of measles in Canada by year and age group, 2005 to 2011.
Year All Ages Less than 1 1 to 4 5 to 9 10 to 14 15 to 19 20 to 24 25 to 29 30 to 39 40 to 59 60 or Greater Age Unspecified

*Data obtained from the Canadian Measles/Rubella Surveillance System.

2005* 6 1 1 0 2 0 0 0 0 0 0 2
2006* 13 4 3 1 0 2 1 0 1 1 0 0
2007* 102 1 11 35 25 5 4 3 12 2 0 4
2008* 62 4 6 9 8 4 1 5 16 8 0 1
2009* 14 0 1 3 2 7 0 0 1 0 0 0
2010* 99 12 11 6 5 10 11 7 22 13 1 1
2011* 750 59 61 60 249 215 25 11 56 14 0 0
Table 2. Reported incidence per 100,000 population of measles in Canada by year and age group, 2005 to 2011
Year All Ages Less than 1 1 to 4 5 to 9 10 to 14 15 to 19 20 to 24 25 to 29 30 to 39 40 to 59 60 or Greater Age Unspecified

*Data obtained from the Canadian Measles/Rubella Surveillance System.

2005* 0.02 0.29 0.07 0.00 0.09 0.00 0.00 0.00 0.00 0.00 0.00 0.01
2006* 0.04 1.14 0.22 0.05 0.00 0.09 0.04 0.00 0.02 0.01 0.00 0.00
2007* 0.31 0.28 0.78 1.94 1.22 0.22 0.18 0.13 0.27 0.02 0.00 0.01
2008* 0.19 1.08 0.42 0.50 0.40 0.18 0.04 0.22 0.35 0.08 0.00 0.00
2009* 0.04 0.00 0.07 0.17 0.10 0.31 0.00 0.00 0.02 0.00 0.00 0.00
2010* 0.29 3.15 0.73 0.33 0.26 0.45 0.47 0.29 0.48 0.13 0.01 0.00
2011* 2.17 15.32 3.97 3.29 13.11 9.79 1.04 0.45 1.21 0.14 0.00 0.00

Measles Resources

Case Definitions

Publications

Guidelines and Recommendations

Other Resources