2019 Measles Outbreak in Samoa

What is measles and why it spreads quickly

Measles is an extremely contagious viral illness characterised by fever, cough, conjunctivitis and a characteristic rash. It spreads through respiratory droplets and remains infectious in the air and on surfaces for hours. Complications can include pneumonia, encephalitis and death, particularly in infants, the malnourished and people with weakened immune systems. High population density, low prior immunity and gaps in vaccination coverage create the conditions for rapid spread.

Contributing factors

The outbreak followed a period of reduced routine vaccination coverage in Samoa. Public confidence in the immunisation programme had been undermined after a safety incident in 2018 that led to a temporary suspension and a sharp fall in uptake. With insufficient population immunity, measles was able to infect large numbers of susceptible people.

Public health response

The Samoan government declared a state of emergency on November 17, 2019 and implemented a set of strict control measures aiming to limit transmission and increase vaccination rates. Measures included:

• Closure of all schools and bans on children under 17 attending public events;
• Mandatory vaccination campaigns, backed by door-to-door outreach and mass clinics;
• A nationwide curfew and cancellation of public and holiday celebrations announced on December 2;
• Instructions for unvaccinated households to display a red flag or cloth to warn others;
• Temporary shutdown of non-essential government services on December 5–6 to redeploy staff into vaccination efforts.

International partners and regional neighbours provided vaccines, medical staff and logistical support to assist the campaign and help manage severe cases.

Impact and aftermath

The outbreak had profound social and medical consequences: many families lost children, routine health services were disrupted, and the emergency measures affected daily life and the economy. The crisis also prompted renewed emphasis on rebuilding trust in immunisation programmes and strengthening routine childhood vaccination to prevent future outbreaks.

Further information

Reported case counts and situational updates can be found through official health communications and partner briefings. For demographic context see population data referenced by local authorities as well as regional reporting on exported cases to neighbouring countries such as Fiji. See population and context and regional updates such as reports of cases in Fiji at regional health reports.