Pathogen and transmission
Measles is an infectious disease caused by measles virus and dreaded for its often severe complications. The highly contagious measles virus is transmitted in droplets, including very small ones (aerosols), when people cough or sneeze. Infectious aerosols can remain airborne for up to two hours after emission.
Measles usually develops in two phases. The first begins 7 to 18 days after infection with fever, tiredness, abdominal pain, sensitivity to light, inflammation of the mucous membrane in the mouth, and is often accompanied by coughing, a runny nose and a sore throat. The second stage follows two to four days after the start of the symptoms, with a burst of high fever. The existing symptoms worsen and only now a typical rash appears.
Uncomplicated cases may heal fairly rapidly without any defects. However, the following (and other) complications can occur: encephalitis (1 in 1,000 cases), measles pneumonia (10 to 60 in 1,000 cases) or middle-ear infections (otitis media). The complications of measles sometimes lead to death. There is no specific therapy for the disease. The treatment is limited to mitigation of symptoms.
Occurrence and frequency
Measles is not specifically a childhood disease. It can occur at any age. Before the vaccine was introduced, measles was a disease that practically all children worldwide developed. It has become far less common since vaccination was introduced. According to the World Health Organisation (WHO), 42% of the countries in the world and more than half of the European countries, including Switzerland since 2018, no longer have endemic measles circulations in 2019. This means that only rare imported or import-related cases were recorded.
The mortality rate for measles is currently between 1 and 3 in every 10,000 cases in industrialised countries. In developing countries it is often 300 - 500 in every 10,000 cases and sometimes even higher. Overall, the number of deaths has fallen sharply with the progress of vaccination. According to the WHO, it has fallen from 1.1 million in 2000 to 61,000 in 2020. The WHO estimates that 32 million deaths have been prevented by vaccination during this period.
The Federal Office of Public Health recommends a combined vaccine against measles, rubella and mumps (MMR-vaccine). The main reason for vaccinating against these three diseases is to protect children and adults in Switzerland from their at times extremely serious complications. Two doses of an MMR-vaccine are recommended: the first at 9 months, the second at 12 months of age. A catch-up immunisation is possible at any age and is recommended for anyone born after 1963 who is not yet immune. Risk check measles.
The vaccine is efficacious, safe and well tolerated. Protection is usually life-long in people who have been fully vaccinated (i.e. with 2 doses). The WHO and its member states are working together to eliminate measles (interruption of endemic circulation) from Europe and other regions by attaining a sufficient vaccine coverage among infants.