A sharp resurgence of measles among young children has been recorded worldwide, with a new study showing a 40% increase in cases among children under five between 2019 and 2023, raising concerns about declining vaccination rates and widening immunity gaps.
The research, published in the journal Nature Medicine, examined measles infections, deaths and vaccination coverage among children under five across 204 countries and territories. The study was led by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington.
Cases and deaths on the rise
Researchers estimate that 15.6 million children under the age of five contracted measles in 2023, up from 11.1 million in 2019.
The increase marks a reversal of decades of progress. Between 1990 and 2019, global measles cases had fallen by almost 80%.
The study also found that measles-related deaths rose during the same period, increasing from an estimated 105,000 deaths in 2019 to approximately 118,000 in 2023.
Vaccination coverage remains below pre-pandemic levels
The resurgence comes as global vaccination rates have yet to recover fully from the disruptions caused by the Covid-19 pandemic.
Coverage with the first dose of the measles vaccine stood at 81% in 2023, compared with 83.6% in 2019.
Researchers estimate that 23.7 million infants did not receive their first measles vaccination in 2023, representing an increase of around 1.7 million children compared with 2019.
Regional disparities
Nearly half of all unvaccinated children were located in sub-Saharan Africa, while roughly 20% were in South Asia, highlighting significant regional inequalities in access to routine immunisation services.
However, researchers cautioned that the threat is not limited to lower-income countries.
Recent outbreaks in the United States demonstrate that measles can rapidly re-emerge in wealthier nations when vaccination coverage declines and immunity gaps develop within communities.
A preventable disease
The findings underscore concerns among public health experts that even small declines in vaccination uptake can lead to significant increases in infections, particularly among young children who are most vulnerable to complications from the disease.
The study adds to growing calls for renewed efforts to strengthen routine childhood immunisation programmes and restore vaccination coverage to levels required to prevent outbreaks.
Source: ANA-MPA
