Meningococcal meningitis, a disease that worries parents

Meningitis is an infection of the meninges, the thin membranes that surround the brain and spinal cord. The causes of infectious meningitis are numerous:

• Viruses;
• bacteria;
• Mushrooms.

The most common are those of viral and bacterial origin. Meningitis of viral origin is the most numerous and heals spontaneously after several weeks. On the other hand, bacterial meningitis is a very serious infection that requires rapid treatment. Invasive meningococcal infections are bacterial infections caused by Neisseria meningitidis. They are usually characterized by meningitis and/or sepsis (blood infection or blood poisoning). The disease occurs when bacteria pass through the protective lining of the nose and throat and enter the bloodstream. Once in the bloodstream, they multiply rapidly, doubling their number every 30 minutes. In some people, the bacteria cross the blood-brain barrier, causing meningitis. Life-threatening meningitis and sepsis are the most common clinical manifestations of this disease.

Meningococcal meningitis, a known disease that worries parents

A study carried out by the CSA Institute between August and September 2022 on the basis of a self-administered online questionnaire on a representative national sample of 1,424 French people aged 18 and over (including 346 parents of children under 5 years and 726 parents of children under 18), reveals that meningococcal meningitis is a disease known by 88% of French people and which worries 58% of parents of children under 5 years old. Besides, 89% of French people are aware that you can die of meningococcal meningitis. Although invasive meningococcal disease mainly affects children under five, adolescents and young adults, anyone can be affected. In 2019, there were 459 cases, including 65 in children under one year old, 62 cases in children aged between 1 and 4 years old, 33 cases in children between 4 and 14 years old and 93 cases between 15 and 24 years old. Since the beginning of 2022, the authorities have considered that a resumption of transmission is possible when social distancing measures and barrier gestures are reduced or less frequently followed in the population.

Invasive meningococcal infections, an unstable epidemiology

Currently in Europe, the majority of cases of invasive meningococcal disease (IMD) are due to serogroups B, C, W and Y but the circulation and incidence of these serogroups are highly variable geographically. Recent trends show a stability of cases due to serogroup B and an increase in those due to serogroups Y and W. There has also been a significant increase in cases due to a strain of serogroup W in Europe, hypervirulent with a mortality rate described as twice that of other serogroups. In France, between 2017 and 2019, thanks to the strengthening of the vaccination strategy against serogroup C, we have observed a 64% reduction in the number of cases of IIM C. And between 2018 and 2019, we observe an increase of 50 % of the number of IIM W cases which becomes the 2nd most frequent. Unfortunately, these infections very often result in the first non-specific symptoms such as fever, loss of appetite, sore throat, diarrhea, irritability: “at this moment, most doctors are not able to to recognize a child affected by the disease, especially if they have not already seen a case of invasive meningococcal disease in their career. Unfortunately, within a few hours the clinical picture becomes more serious and the patient can die even if everything is done in the intensive care unit” laments Dr Haas, head of the pediatrics department at the Princess Grace Hospital in Monaco.

Vaccination, a means of prevention against invasive meningococcal infections

Faced with non-specific beginning symptoms and the very high risk of death and disability following this disease, vaccination appears to be an effective means of prevention, particularly in the eyes of the families of victims. Annie Hamel, head of the Ile de France branch of the Petit Ange association, experienced this tragedy herself when she lost her 18-year-old son to meningococcal meningitis: “At the time, I received no information on vaccination and today our fight is to inform parents as well as possible in order to prevent other families from experiencing this tragedy.”

Currently, several vaccines are available in Europe to prevent meningococcal infections. They include monovalent vaccines against serogroups B or C and quadrivalent vaccines against four serogroups (A, C, W and Y). Moreover, Sanofi announces today the launch in France of its new quadrivalent MendQuadfi® vaccine for active immunization against invasive meningococcal infections of serogroups A, C, W and Y, available from the age of 12 months.

In France, vaccination against serogroup C meningococcal infections (one dose at 5 months and a second dose at 12 months) is compulsory for all children born on or after January 1, 2018. Since 2022, vaccination against serogroup B invasive meningococcal infections is recommended for all infants according to the following schedule: first dose at 3 months of age, second dose at 5 months and booster dose at 12 months. So neara third (31%) of French people do not know that there are vaccines to prevent meningococcal meningitisit therefore seems necessary to better inform them about the means of preventing these very serious diseases.