Measles: symptoms and signs
Learn more about what the measles virus is and how measles spreads
September 20, 2023
Read the Spanish version – Sarampión: síntomas y signos
What is measles?
Measles is a highly contagious virus that lives in the mucus of the nose and throat of an infected person. Symptoms appear 10 to 12 days after contact with the virus.
Common measles symptoms include:
How measles spreads
The measles virus can live for up to 2 hours in an airspace where an infected person coughed or sneezed.
If one person has measles, up to 90% of at-risk people close to that person will also become infected.
Infected people can spread measles to others 4 days before through 4 days after the rash appears.
After being exposed to the measles virus, it can incubate for up to 21 days.
Measles can cause serious health complications, including ear infections, diarrhea, pneumonia, and encephalitis (an inflammation of the brain), impacting the daily lives of patients and their caretakers (e.g., can result in lost work time or missed school days).
Measles can be serious and lead to complications
- Measles can cause serious health complications, affecting several organ systems such as ears, eyes leading to blindness, gastrointestinal tract, central nervous system including inflammation of the brain and death.
- Approximately 30 percent of reported measles cases have one or more complications, such as encephalitis or pneumonia.
- Approximately 567 people die globally from measles-related complications each day, that equates to 24 deaths every hour.
Understanding measles outbreaks
Between 2000-2018, annual reported measles deaths decreased by 73% globally.
The number of measles cases increased 659% in 2019 (874,304 cases) compared to 2016 (132,490 cases)
Natural disaster and/or conflict can put countries at greater risk for deadly measles outbreaks by damaging health infrastructure, interrupting health services and placing people in overcrowded residential camps.
Before the introduction of a measles vaccine in 1963, measles caused an estimated 2.6 million deaths annually.
149 countries reported 874,304 measles cases globally in 2019
World Health Organization (WHO) member states reported more measles cases in 2019 than in any single year since 1996.
In 2020, the number of globally reported measles cases was lower, likely due in part to regulations put in place during the COVID-19 pandemic. However, during the same year, more than 22 million infants missed their first dose of measles-containing vaccine, 3 million more than in 2019, placing communities at heightened risk for outbreaks. In 2022, the WHO and the United Nations Children Fund (UNICEF) reported a worldwide 79% increase in measles cases in the first two months of the year as compared with the same period in 2021, and warn of the risk for preventable diseases as restrictions continue to ease.
Measles is still common in many parts of the world, and travelers with measles can bring the disease to countries that have largely eliminated it. Measles can spread rapidly.
