The UK’s health services are battling a measles outbreak, causing alarm in a nation that had eliminated the disease in 2017.
On January 19, the UK Health Security Agency (UKHSA), the public health authority, declared a national incident over the rise in measles cases. The agency has recorded more than 300 cases in England since October 1, 2023 (see ’Measles surge’).
A decline in uptake of the measles, mumps and rubella (MMR) vaccine, which is administered in two doses, during the COVID-19 pandemic has spurred the spread of the disease in England and the rest of Europe, while small outbreaks have occurred in a handful of US states.
Measles is caused by a virus and is highly contagious. It is transmitted by coughing and sneezing. Symptoms include fever, runny nose, and itchy, reddish-brown, blotchy rash. "It is considered one of the most infectious respiratory infections there is," says population health researcher Helen Bedford of University College London. Those most at risk include infants, young children, pregnant people, and people with a weakened immune system.
Why are measles cases increasing in the UK?
Low measles vaccine uptake is a key driver of measles cases in the UK, researchers say. Around 85% of children in England have received two doses of the MMR vaccine by the age of five, according to National Health Service (NHS) data. This is below the vaccination rate of at least 95% needed to achieve "herd immunity", which substantially reduces the spread of disease, as recommended by the World Health Organization (WHO; see "Injections needed") .
"It is worrying, but not all that surprising, to see another outbreak of measles in the United Kingdom," pediatrician Ronny Cheung of London’s Evelina Children’s Hospital said in a statement to the UK’s Science Media Centre. "The fact is that vaccination coverage for children under 5 years old is now the lowest it has been in 10 years," he said.
The COVID-19 pandemic made the situation worse, Bedford says. At first, the number of measles cases decreased due to social distancing measures. But vaccine acceptance also declined, contributing to the latest surge, he says.
Additionally, anti-vaccine messaging during the pandemic caused some people to question the safety of the vaccines, which could have delayed their acceptance, Bedford says. “People have more questions that, unfortunately, due to cuts in public health funding, are not always adequately addressed,” she says.
What is happening elsewhere?
Since December 1, there have been 23 confirmed cases of measles in the United States, in Georgia, Missouri, New Jersey and Pennsylvania. Many of the cases were linked to international travelers returning to the country and reflect an increase in the number of measles cases worldwide, according to a bulletin sent by the US Centers for Disease Control and Prevention on January 25. . Last year, 58 cases were reported in the United States, compared to 121 in 2022. This is far fewer than the more than 1,200 infections in the United States in 2019.
But Europe faces a more alarming situation. Measles cases increased 45-fold in the WHO European region between 2022 and 2023. In 2023, the region’s 40 member states reported about 42,200 measles cases, up from less than 1,000 in 2022.
The increase in cases is also a result of declining national vaccination rates, which fell from 92%, on average, in 2019 to 91% in 2022, according to the WHO.
Globally, the number of measles cases increased by 18% between 2021 and 2022, and measles deaths increased by 43%, according to a WHO report published last November.
Note: New variant of the measles virus A study carried out by Italian researchers from the University of Milan and the Istituto Superiore di Sanità (ISS) discovered a new variant of the measles virus that produces false negatives and makes traditional tests ineffective in these cases. Since January 2024, five cases of measles with the new variant have been confirmed in the area comprising the metropolitan city of Milan and its surroundings in Lombardy, according to an Ansa cable. All cases are classified as genotype D8 and "sporadic", since no clear epidemiological link was found between them. This was reported in a study carried out by researchers from the State University of Milan and the Istituto Superiore di Sanità, published in Eurosurveillance. In three of the five cases identified, "recent travel history was reported, destinations included Uzbekistan, Thailand and southern Italy. In particular, two of these cases, each with a travel history to southern Italy or Thailand, were infected with strains of MeV (measles virus) characterized by the three mismatches described by Pérez-Rodríguez." The aforementioned is a researcher who carried out a study with his team in Switzerland, a region that borders the area where the Lombard cases were identified. "Our results suggest that MeV with specific mutations detected by Swiss molecular surveillance are already circulating in Italy," the researchers noted. They added that they can "be detected with reduced sensitivity by many currently used diagnostic tests." * Source : Telam / ANSA |
