Outbreak of meningitis in Nigeria: a silent fight

Meningitis is an infection characterized by inflammation of the lining of the brain and spinal cord. The disease has viral and bacterial causes, with the latter accounting for most cases. Three main bacterial species are responsible for causing meningitis, viz: Streptococcus pneumoniae (Sp), Haemophilus influenzae type b (Hib), and Neisseria meningitidis (Nm)1. It has grave complications and can be fatal in up to 5–10% of cases detected and treated early, and worse still, up to 50% of untreated cases1. Between the dates of 1 October 2022 and 16 April 2023, there have been a cumulative total of 1686 cases of meningitis that were suspected in Nigeria2, 532 cases that were confirmed, and 124 deaths that occurred, resulting in a case fatality rate (CFR) of 7%2. These cases have been reported from 81 local government areas (LGAs) located in 22 out of the 36 administrative states, as well as the Federal Capital Territory (FCT), all within Nigeria2. The suspected cases comprised 961 individuals, of which 57% are males. The age group of 1–15 years old exhibits the greatest percentage of documented cases2. Jigawa state constitutes a significant proportion of the total suspected cases, accounting for 74% (n = 1252). It is noteworthy that this state shares a border with the Zinder region in Niger, which has been grappling with a meningitis outbreak since October 20222. Amidst the complex interplay of the incoming dry season, simultaneous occurrences of other epidemics and protracted humanitarian crisis (insecurity, displacement, and conflict) ongoing in the country, this outbreak is only likely to worsen and is therefore viewed as a global public health concern3. Efforts to stem the tide are ongoing, majorly targeted at upping vaccine coverage by mass vaccination, breaking the chain of transmission, equipping the health systems for case finding and management3, appropriate chemoprophylaxis for contacts, and prevention of complications. Meningitis is a disease of public health concern with significant public health burden and consequence, especially in countries with very limited resources for healthcare expenditure like Nigeria. Meningitis is caused by known bacterial pathogens, and the prevention of this disease is through mass vaccination, especially in the most vulnerable areas across the country3. Morbidity caused by the aftermath of surviving meningitis disease is disturbing as it can cause significant long-term health problems, like neurological damage, hearing and cognitive impairment, which can limit their ability to work and contribute to the economy in the future. Meningitis outbreak in Nigeria has a tremendous economic impact, clearly outbreaks burden the costs of healthcare expenditure and loose productivity, thinning out the healthcare budget from increased healthcare costs4. Outbreaks can also have indirect impact like disruption in education of school children in affected areas to prevent disease spread. Meningitis outbreak can also have both physical and mental impacts on the affected individuals and their families5. Survivors can experience post-traumatic stress disorder and depression, while families that may have lost a loved one during the recurrent outbreak may be affected psychologically. The fear and anxiety caused by the disease can result in long-lasting effects on mental health leading to a decrease in overall well-being and quality of life5. Moreover, the recurring outbreaks of meningitis can also cause fear and panic among the population, leading to mistrust in the healthcare system and reluctance to seek care, vaccination, or participate in outbreak response measures. This situation can exacerbate the spread of the disease, leading to prolonged outbreaks and increased healthcare costs on the health system. Nigeria has a poor healthcare coverage with insufficient numbers of qualified health staff, straining the already limited health resources in the country leading to poor and slow public health response to meningitis outbreak in Nigeria6. The current strategy for eliminating meningitis is to assess the epidemic risk by observing the number of cases documented in a particular population during the dry season. Sequel to the assessment, operational thresholds would be formulated, and these would activate the alert threshold, where the case monitoring is intensified, and invariably the activation of the epidemic threshold, which involves vaccination and the use of specific antibiotics for treatment7. Vaccination remains the mainstay of preventing meningitis epidemics; the current effort of the World Health Organization (WHO) in controlling the outbreak of meningitis in Niger is based on the available evidence following the approval of the Neisseria meningitidis Serogroup A (NmA) conjugate vaccine MenAfriVac, which was proven to be effective for the elimination of NmA epidemics7. It has been reported that no epidemics caused by NmA have occurred in countries where the MenAfriVac vaccine is administered7. The introduction of the MenAfriVac changed the narrative and other Neisseria meningitidis Serogroups are now predominant, which necessitated the WHO to recommend the use of multivalent meningococcal conjugate vaccines in preventing and eliminating bacterial meningitis epidemics in Nigeria. The WHO also recommended that the multivalent meningococcal conjugate vaccines should be introduced into routine immunization programs7. In the event of an established case of meningitis, the current WHO guideline prescribes prompt antibiotics administration to close contacts of the case. This has been found to decrease the risk of transmission7. However, for those residing outside the meningitis belt, chemoprophylaxis is prescribed for close contacts within the same household, and for those within the meningitis belt, chemoprophylaxis is only prescribed in non-endemic conditions. Given the potentially fatal outcomes of the disease and its public health magnitude, it is imperative to act promptly to curb its menace. Introducing a seasonal chemoprevention program can help to reduce the proportion of meningococcal carriage in the population. The program should be centered around the start of the epidemic season (January to June) and the most susceptible age groups (1–4 years). Suggested antibiotics which are effective for chemoprevention include rifampicin, ceftriaxone, and azithromycin. There should be an improvement in surveillance, especially around the borders with other countries in the meningitis belt8. Throat swab culture on selective media is the standard method of detection of carriage. This will help reduce cross-border transmission of infection and the outbreak potential of the population. Contact tracing is another very important aspect of surveillance that needs more focus, as contacts of known cases are potential carriers. Throat swab collection and chemoprevention, as well as post-exposure immunoprophylaxis for contacts, can help to minimize the spread of the disease. Finally, as the causative pathogens thrive in poor socio-economic conditions where there is poor health access, more investment in the improvement of living standards would aid in lowering the occurrence of meningitis outbreaks and other related diseases. Strengthening the health system, especially at the primary health level, will increase access to basic health needs and help in the early diagnosis and treatment of meningitis cases. Ethical approval The information provided in the manuscript does not require an ethics application or approval. Consent No patients were sorted. Not applicable. Sources of funding Not applicable. Author contribution Study concept or design: A.T.A.; research data/image generation and manuscript writing and revision: all the authors. Conflicts of interest disclosure There are no conflicts of interest. Research registration unique identifying number (UIN) None. Guarantor Fatima Abdirazak Ahmed. Data availability statement Available through the manuscript (with included figures). No extra data generated. Provenance and peer review Not applicable.