National immunisation programme reveals vaccine prevents 3 in 4 cases of deadly childhood disease
Results from the national immunisation programme in England have shown that a vaccine against meningococcal group B (MenB) disease has prevented hundreds of cases in children since its introduction, saving many lives and preventing long-term conditions including amputations and cerebral palsy.
The 4CMenB vaccine which is also known as Bexsero® was introduced into the publicly funded routine immunisation programme in the UK in September 2015. Given to infants from 8 weeks old, the impact of its introduction has been closely monitored by Public Health England. The results published today in the New England Journal of Medicine, show that the vaccine has prevented an estimated 277 cases over a three-year period.
Meningococcal disease is a bacterial infection, and causes meningitis if the infection is in the brain, or septicaemia if in the blood. There are different groups of meningococcal bacteria, and the vaccine is designed to prevent group B disease, which is particularly prevalent among young children and infants, especially in the first three years of life.
The vaccine itself was approved for use after antibodies made by the vaccine were shown to kill the meningococcal bacteria in the laboratory, but initially it hadn’t been shown to prevent disease in people. This is the biggest analysis since the programme opened, and the first of its kind in the world, demonstrating a large reduction in MenB cases in children who were vaccinated as part of the national immunisation programme.
Dr Shamez Ladhani, clinical epidemiologist at Public Health England, and part of the Paediatric Infectious Diseases Research Group at St George’s, University of London, has led on the work to evaluate the vaccine’s success.
“Meningococcal disease is one of the most feared infectious diseases,” he says.
“From the moment first symptoms arise, death can occur within twenty-four hours. It’s very quick and even with treatment, it’s possible doctors might not be able to save a life.”
For those that do survive, people are often left with severe complications. “They can have lifelong conditions like skin scarring and limb amputations if the infection is in the blood,” adds Dr Ladhani. “If the infection is in the brain, it can lead to hearing loss, blindness, epilepsy or cerebral palsy.”
Now that results show the vaccine definitely protects against MenB disease, researchers believe it is likely that the vaccine will also help protect against other meningococcal groups because the bacteria are very similar. The vaccine may also help protect against gonorrhoea, one of the most common sexually transmitted infections worldwide.
“There are some really exciting data to show that this new vaccine might protect against gonorrhoea as well because the bacteria causing meningococcal disease and gonorrhoea are very closely related,” says Dr Ladhani.
“We are all interested to see if this vaccine prevents gonorrhoea which is becoming increasingly resistant to all available antibiotics.”
Dr Ladhani is also the co-author of another study published in the same volume of New England Journal of Medicine showing that vaccinating teenagers with the MenB vaccine doesn’t prevent them from carrying the meningococcus bacteria at the back of their nose and throats.
Teenagers are considered to be the “reservoir” for the bacteria. This means that, unlike vaccines against the other meningococcal groups such as A, C, W and Y, the MenB vaccine is unlikely to provide herd immunity , so only those who are vaccinated will be protected against this devastating infection.
The results published today provide further evidence that vaccines are the most effective way of defeating meningococcal disease.
“Considering how rare it is, meningococcal disease really strikes fear among parents and doctors,” says Dr Ladhani.
“It acts so rapidly and before you know it, patients can be in intensive care. That’s why this vaccine had to come into the national immunisation programme.”
Published: 23 January 2020