A report by the World Health Organization (WHO) in collaboration with the US Centers for Disease Control and Prevention (CDC) have found that disruption caused by the Covid-19 pandemic is endangering global progress in the fight against measles.
The report found that during 2020, more than 22 million infants missed their first dose of the measles vaccine – a year-on-year rise of three million compared with 2019. The rise is the largest increase in unvaccinated infants in two decades. Only 70 per cent of children worldwide also received their second dose of the measles vaccine – well below the 95 per cent coverage needed to prevent the spread of the disease.
One factor in this reduction is the cancellation of 24 measles vaccination campaigns in 23 countries which had previously been planned for 2020 due to the onset of the Covid-19 pandemic – leaving over 93 million people at risk of the disease.
A fall in cases in 2020 – but health risks further ahead
WHO says that reported measles cases decreased by more than 80 per cent in 2020, however the organisation warns that ‘lower reported measles cases… must not mask the growing risk of measles to children worldwide’.
The reduction can at least partially be credited to changes in hygiene practices in many parts of the world intended to mitigate Covid-19, such as masking, handwashing and distancing, which also reduced the spread of other transmissible diseases during the pandemic.
“While reported measles cases dropped in 2020, evidence suggests we are likely seeing the calm before the storm as the risk of outbreaks continues to grow around the world,” said Dr Kate O’Brien, Director of WHO’s Department of Immunisation, Vaccines and Biologicals. “It’s critical that countries vaccinate as quickly as possible against Covid-19, but this requires new resources so that it does not come at the cost of essential immunisation programs. Routine immunisation must be protected and strengthened; otherwise, we risk trading one deadly disease for another.”
A decline in measles surveillance measures
The report also found that measles surveillance has also deteriorated, with the lowest number of specimens sent for laboratory testing in over a decade. Weakened measles monitoring, testing and reporting could also jeopardise countries’ ability to prevent outbreaks of the highly infectious disease.
In 2020, major measles outbreaks occurred in 26 countries and accounted for 84 per cent of all reported cases that year.
Measles is one of the world’s most contagious human viruses, but is almost entirely preventable through vaccination. Over the past two decades the measles vaccine is estimated to have averted over 30 million deaths worldwide, with estimated deaths due to measles falling from around 1,070,000 in 2000 to just 60,700 in 2020.
However, WHO and the CDC have warned in recent years that gains made over the past two decades may be under threat. The organisations previously reported in 2020 that there had been a 50 per cent rise in measles cases in all WHO regions between 2016 and 2019, before the coronavirus pandemic undermined this trend.
“The pandemic is having a huge impact on countries’ ability to deliver essential health services such as routine immunisation, placing millions of people, mainly children, at risk of highly infectious diseases such as measles,” said Anuradha Gupta, Deputy CEO of Gavi the Vaccine Alliance. “We must urgently address the critical measles immunity gaps with a particular focus on reaching zero-dose children who are most at risk of devastating measles outbreaks.”