Teachers and parents

Links to Alberta Curriculum

Grade 8

  • I can interpret the healthy function of human body systems, and illustrate ways the body reacts to internal and external stimuli
  • I can describe areas of scientific investigation leading to new knowledge about body systems and to new medical applications

Grades 8 and 9

I can apply the research process

  • Integrate and synthesize concepts to provide an informed point of view on a research question or an issue
  • Determine how information serves a variety of purposes and that the accuracy or relevance of information may need verification

Grade 9

  • I can describe the effect of: bias; use of language; ethics; cost; time and timing; privacy; and cultural sensitivity on the collection of data.
  • I can demonstrate an understanding of the role of probability in society.


Measles, also called red measles or rubeola, is an infectious disease caused by the measles virus.

Signs and symptoms

The average incubation period (the time from infection to the onset of signs and symptoms) of measles is generally 10–12 days (Moss, 2017). Measles begins with a fever, cough, coryza (runny nose), and conjunctivitis (pink eye), and within 3–4 days, a distinctive red rash appears on the face and behind the ears, and then spreads down the body.


The measles virus spreads from person to person through small airborne and respiratory droplets (from breathing, speaking, sneezing, or coughing) that can remain suspended in the air for up to 2 hours (Moss, 2017). The infectious period (the time when the measles virus can be spread) lasts for about 4 days before and after the red rash appears, which increases the contagiousness of the measles virus.

Measles is one of the most contagious infectious diseases worldwide. The basic reproductive number (R0, the average number of secondary infections resulting from one typical infection in a susceptible population) of measles has been estimated to be 9–18 depending on setting (e.g., degree and frequency of contact) (Moss, 2017).

To achieve herd immunity, which interrupts the transmission of measles and protects those who cannot be vaccinated (e.g., infants <1 year of age and those with compromised immune systems), a population immunity threshold of 89–94% is required through vaccination or natural infection (Moss, 2017).

Complications from measles

Measles can be serious.

Common complications

  • Ear infections (~10% of children with measles)
  • Diarrhea (<10% of people with measles)

Serious complications

  • Hospitalization (~1 in 5 people)
  • Pneumonia (~1 in 20 children)
  • Encephalitis (1 in 1000 children)
  • Death (1–3 in 1000 children)
  • Complications during pregnancy including low birth weight and preterm birth

(CDC, 2020)

Who is at highest risk?

  • Young children <5 years of age
  • Adults >20 years of age
  • Pregnant individuals
  • People with compromised immune systems (e.g., individuals with cancer or transplants who are taking immunosuppressive therapy)
  • People who are undernourished

(Moss, 2017)

Immune amnesia

Measles infection is thought to damage and suppress the immune system by wiping out antibodies developed against pathogens that a person has previously been exposed to. This wiping-out of immune memory has been called immune amnesia.

New research in the journal Science from the lab of Stephen Elledge at Harvard Medical School and Brigham and Women’s Hospital reveals how measles infection reduces protection against other diseases. Read more at Harvard Medical School.

Elimination–and recent outbreaks

In Canada, measles has been eliminated since 1998 (Public Health Agency of Canada, 2019).

In recent years, vaccine hesitancy as well as complacency about the risks of vaccine-preventable diseases have led to declines in measles vaccination rates, resulting in outbreaks in both Canada and the United States (Phadke, Bednarczyk, & Omer, 2020; Public Health Agency of Canada, 2019).


Stories of families impacted by measles

Laurie’s vaccination story

Laurie shares her story about measles. (Source: Government of Canada)

Maggie’s story

Dr. Tim Jacks, a pediatrician from Arizona, tells the story of his young daughter Maggie and how she needed to be protected from measles while also fighting cancer. (Source: Vaccinate Your Family)

Mobius’ story

Mobius’ parents shared their family’s story with the California Immunization Coalition at ShotByShot.org

Measles vaccine

The measles vaccine is the safest and most effective way to prevent measles (Moss, 2017). Usually, the measles vaccine is combined with other vaccines in the measles, mumps, and rubella (MMR) vaccine. The MMR vaccine contains weakened parts of these viruses that do not cause severe illness in people with healthy immune systems. After getting the vaccine, the body will create antibodies that recognize and fight these viruses.

The measles vaccine is safe and effective

Before the measles vaccine was used widely beginning in the 1980s, more than 2 million people worldwide died of measles each year (Moss, 2017). Today, more than 100,000 people worldwide die of measles each year. Increased global vaccine coverage is decreasing measles cases and deaths (World Health Organization, 2019).

Measles cases in Canada have decreased by >99% because of the measles vaccine (Public Health Agency of Canada, 2019).

Infographic: Vaccines Work
(Image credit: Public Health Agency of Canada)

MMR vaccine does not cause autism

Many studies have found that there is no evidence that vaccines–including the measles, mumps, and rubella (MMR) vaccine–cause autism.

Many of these claims stem from a paper that was ultimately retracted from The Lancet (Wakefield et al., 1998) and whose lead author, Andrew Wakefield, was found to have engaged in scientific misconduct. As a result, Wakefield’s medical license was revoked.

Wakefield et al. paper


In 1998, a prominent medical journal, the Lancet, published a case series (Wakefield et al., 1998) assembled by Andrew Wakefield and others. The paper reported on 12 children with gastrointestinal symptoms, and suggested a link between the measles, mumps, and rubella (MMR) vaccine and autism.


Not longer after the Wakefield et al. paper was published, concerns were raised and research was conducted that refuted Wakefield et al.’s suggested link between MMR vaccine and autism (Rao & Andrade, 2011; Taylor et al., 1999).


In 2004, 10 of 12 co-authors of the paper issued a retraction statement that addressed some of these concerns: “no causal link was established between MMR vaccine and autism as the data were insufficient” (Murch et al., 2004; Rao & Andrade, 2011). The Lancet also acknowledged that Wakefield et al. failed to disclose conflicts of interest (Horton, 2004).

The Wakefield et al. paper was fully retracted by the Lancet in 2010 (The Editors of the Lancet, 2010). By this time, it was established that Wakefield et al. had committed ethical misconduct, by failing to obtain necessary ethical clearance, as well as scientific misconduct, by misrepresenting how participants were recruited (Rao & Andrade, 2011).


The Wakefield et al. paper has had lasting consequences.

In the United Kingdom, MMR vaccination rates hit a low in 2003–2004 (Cockman, 2011). It has taken considerable public health intervention to counter increase vaccination rates. Cockman (2011) provides a quality improvement report for a London Borough that outlines how the rates for the first MMR vaccine before 2 years of age increased from 80% in September 2009 to 94% in March 2011.

Vaccine hesitancy, skepticism, and refusal continue to be significant factors in preventable outbreaks of measles around the world (Phadke et al., 2020).

Wakefield, A. J., Murch, S. H., Anthony, A., Linnell, J., Casson, D. M., Malik, M., … Walker-Smith, J. A. (1998). RETRACTED: Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children. The Lancet, 351, 637–641. https://doi.org/10.1016/s0140-6736(97)11096-0

Areas for discussion with students and further activities

  • Ethics and conflicts of interest
  • Scientific rigor and integrity
  • Study design
  • Sample selection and representativeness

CDC. (2020). Complications of measles. Retrieved from https://www.cdc.gov/measles/symptoms/complications.html

Cockman, P., Dawson, L., Mathur, R., & Hull, S. (2011). Improving MMR vaccination rates: herd immunity is a realistic goal. BMJ 343, d5703. https://doi.org/10.1136/bmj.d5703

Horton, R. (2004). A statement by the editors of The Lancet [Review of A statement by the editors of The Lancet]. The Lancet363(9411), 820–821. https://doi.org/10.1016/S0140-6736(04)15699-7

Kooistra, B., Dijkman, B., Einhorn, T. A., & Bhandari, M. (2009). How to design a good case series. The Journal of Bone and Joint Surgery, 91, 21–26. https://doi.org/10.2106/JBJS.H.01573

Moss, W. J. (2017). Measles. The Lancet, 390, 2490–2502. https://doi.org/10.1016/S0140-6736(17)31463-0

Murch, S. H., Anthony, A., Casson, D. H., Malik, M., Berelowitz, M., Dhillon, A. P., Thomson, M. A., Valentine, A., Davies, S. E., & Walker-Smith, J. A. (2004). Retraction of an interpretation. The Lancet363(9411), 750. https://doi.org/10.1016/S0140-6736(04)15715-2

Phadke, V. K., Bednarczyk, R. A., & Omer, S. B. (2020). Vaccine Refusal and Measles Outbreaks in the US. Journal of the American Medical Association, 324(13), 1344–1345. https://doi.org/10.1001/jama.2020.14828

Public Health Agency of Canada. (2019, April 8). Measles in Canada. Retrieved from https://www.canada.ca/en/public-health/services/diseases/measles/measles-in-canada.html

Rao, T. S. S., & Andrade, C. (2011). The MMR vaccine and autism: Sensation, refutation, retraction, and fraud. Indian Journal of Psychiatry53(2), 95–96. https://doi.org/10.4103/0019-5545.82529

Taylor, B., Miller, E., Farrington, C. P., Petropoulos, M. C., Favot-Mayaud, I., Li, J., & Waight, P. A. (1999). Autism and measles, mumps, and rubella vaccine: no epidemiological evidence for a causal association. The Lancet353(9169), 2026–2029. https://doi.org/10.1016/s0140-6736(99)01239-8

The Editors of The Lancet. (2010). Retraction–Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children. The Lancet, 375, 445. https://doi.org/10.1016/S0140-6736(10)60175-4

Wakefield, A. J., Murch, S. H., Anthony, A., Linnell, J., Casson, D. M., Malik, M., … Walker-Smith, J. A. (1998). RETRACTED: Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children. The Lancet, 351, 637–641. https://doi.org/10.1016/s0140-6736(97)11096-0

World Health Organization. (2019). Measles. Retrieved from https://www.who.int/news-room/fact-sheets/detail/measles