US measles cases exceed 2025 record as vaccination rates dip
Officials warn that declining immunisation coverage and political scepticism are undermining herd immunity, leaving vulnerable populations exposed to a resurgence of a previously eliminated disease.
The United States has recorded 2,318 cases of measles in 2026, surpassing the previous year’s record total of 2,289, according to an update from the US Centers for Disease Control and Prevention (CDC). The figure, shared on Friday, marks the highest number of cases since 1991, with five months of the year still remaining. Health officials attribute the surge to a combination of declining vaccination rates and systemic barriers to testing and reporting.
National immunisation rates for kindergartners against measles, mumps, and rubella fell to 92.5 percent during the 2024-2025 school year. This decline is significant given that a 95 percent community vaccination rate is generally required to prevent outbreaks. The drop in coverage has left young children and individuals with fragile immune systems particularly vulnerable, reversing progress made when the US eliminated local measles spread in 2000.
Major outbreaks are currently concentrated in South Carolina, Utah, and Arizona. South Carolina health authorities have recorded 997 cases, describing it as the state’s worst outbreak in 35 years. However, officials cautioned that this figure is likely an undercount, as reporting relies on voluntary testing and information sharing with healthcare providers.
Dr Varun Shetty, chief epidemiologist for Texas, emphasised that reported cases almost always underestimate the actual scale of transmission. He noted that the data is constrained by barriers to testing and the willingness of individuals to share information with public health authorities. Shetty stressed that high vaccination coverage is critical not only for individual protection but for maintaining community immunity.
The resurgence of the disease has occurred amidst heightened political scepticism regarding immunisation. The source material notes that prominent members of the administration of US President Donald Trump have sought to roll back vaccination efforts, despite a strong scientific consensus on their effectiveness. This political opposition is cited as a factor contributing to the decline in uptake and the subsequent rise in cases.
