Meningitis

Scenario at a look

From 1 November 2022 to 27 January 2023, a complete of 559 circumstances of meningitis (of which 111 are laboratory confirmed), together with 18 deaths (general CFR 3.2%), have been reported from Zinder Area, southeast of Niger, in comparison with the 231 circumstances reported throughout 1 November 2021 to 31 January 2022. The vast majority of laboratory-confirmed circumstances (104/111; 93.7%) are because of Neisseria meningitidis serogroup C (NmC). Reactive vaccination campaigns with the trivalent ACW meningococcal polysaccharide vaccine have been carried out.

Niger is situated largely within the African meningitis belt with seasonal outbreaks recurring yearly. Nevertheless, the continuing outbreak reveals each an elevated variety of circumstances and an elevated development fee in comparison with the earlier seasons.

Zinder area shares a world border with Jigawa State in Nigeria the place a NmC outbreak can also be ongoing, confirming the chance of worldwide unfold. Furthermore, the simultaneous incidence of different epidemics, insecurity and inhabitants displacement, all within the context of a protracted humanitarian disaster, are prone to contribute to the unfold of the outbreak in different international locations of the West African subregion.

WHO assesses the chance posed by the present meningitis outbreak in Niger as excessive on the nationwide degree, reasonable on the regional degree, and low on the international degree.

Description of the state of affairs

Being situated within the African meningitis belt, Niger has been affected by a number of meningitis epidemics leading to 20 789 circumstances and 1369 deaths (CFR 6.6%) reported since 2015.

From 1 November 2022 to 27 January 2023, a complete of 559 circumstances of meningitis (of which 111 are laboratory confirmed), together with 18 deaths (general CFR 3.2%) have been reported from Zinder area, southeast of Niger, in comparison with the 231 circumstances reported throughout 1 November 2021 to 31 January 2022.

The final meningitis outbreak within the Zinder area, occurred within the 2021/2022 season, with a complete of 372 circumstances, together with 12 deaths (CFR 3%).

Determine 1. Epicurve of circumstances of meningitis reported in Niger by month, 1 October 2021 – 27 January 2023.

Of the 228 samples collected from suspected circumstances, 154 (67.5%) have been analyzed by Niamey’s Heart for Medical and Well being Analysis (CERMES). Neisseria meningitidis serogroup C was recognized within the majority of confirmed circumstances (n=104; 93.7%), adopted by Streptococcus pneumoniae (n=5; 4.5%) and Haemophilus influenzae (n=2; 1.8%). The remaining 43 samples examined unfavourable.

Males symbolize 53% of all circumstances. Among the many complete of 559 circumstances of meningitis, folks beneath 20 years of age are probably the most affected by the outbreak (n=538; 96.3%), with 202 circumstances (36.2%) reported within the 10-14 years age group, adopted by the 5-9 years age group with 153 circumstances (27.4%), the 15-19 years age group with 107 circumstances (19.1%), and the 0-4 years age group with 76 circumstances (13.6%).

Essentially the most affected well being district of Zinder area is Dungass (342 circumstances, 6 deaths), adopted by Matamèye (98 circumstances, 3 deaths), Mirriah (72 circumstances, 3 deaths), Magaria (38 circumstances, 5 deaths), Zinder ville (7 circumstances, 1 dying) and Gouré (2 circumstances, 0 deaths).

Determine 2. Distribution of reported meningitis circumstances by well being district, Zinder area, Niger, 1 November 2022 – 27 January 2023.

Epidemiology of meningitis

Meningitis is a critical an infection of the meninges, the membranes overlaying the mind and spinal twine. A number of completely different micro organism may cause meningitis, nonetheless, Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis (N. meningitis) are probably the most frequent ones, and are transmitted from individual to individual by means of droplets of respiratory or throat secretions from contaminated folks.

A complete of 12 serogroups of N. meningitidis have been recognized, six of which (A, B, C, W, X and Y) may cause meningococcal meningitis epidemics.

The common incubation interval is 4 days however can vary between 2 and 10 days. The commonest signs of meningitis are a stiff neck, excessive fever, sensitivity to gentle, confusion, complications and vomiting. Even with early analysis and enough remedy, 5% to 10% of sufferers die, usually inside 24 to 48 hours after the onset of signs. Bacterial meningitis might end in mind injury, listening to loss or a studying incapacity in 10% to twenty% of survivors. A much less frequent, however much more extreme (and sometimes deadly), type of meningococcal illness is meningococcal septicaemia, which is characterised by a haemorrhagic rash and fast circulatory collapse.

The best burden of illness is seen in a area of sub-Saharan Africa, often known as the African Meningitis Belt, which is very recognised to be at excessive danger of meningococcal but in addition pneumococcal meningitis epidemics.

Niger is situated largely within the African meningitis belt, the place meningitis epidemics usually comply with a seasonal sample (often from January to June), with a measurement that varies from 12 months to 12 months. In 2015, a big meningitis outbreak attributed to NmC occurred, affecting practically 10 000 folks. In 2009 and 2006, meningitis outbreaks brought on by N. meningitidis serogroups A (NmA) and X (NmX), respectively, have been additionally reported. Haemophilus influenzae and Streptococcus pneumoniae are two different necessary pathogens that contribute considerably to the bacterial meningitis burden inside Niger.

Licensed vaccines in opposition to meningococcal, pneumococcal and haemophilus influenzae illnesses have been obtainable for a few years. These micro organism have a number of completely different strains (often known as serotypes or serogroups) and vaccines are designed to guard in opposition to probably the most dangerous strains. Over time, there have been main enhancements in pressure protection and vaccine availability, however no common vaccine in opposition to these infections exists.

Within the African meningitis belt, meningococcus serogroup A accounted for 80–85% of meningitis epidemics earlier than the introduction of a meningococcal A conjugate vaccine by means of mass preventive campaigns (since 2010) and into routine immunization programmes (since 2016). Amongst vaccinated populations, incidence of serogroup A meningitis has declined by greater than 99%, and no serogroup A case has been confirmed since 2017.

Nevertheless, circumstances of meningitis and outbreaks because of different meningococcal serogroups, aside from serogroup B, proceed to strike.

Meningococcal meningitis stays a public well being concern with a excessive case fatality fee and resulting in critical long-term issues.

Stopping meningitis by means of vaccination is the simplest option to scale back the burden and affect of the illness by delivering long-lasting safety. The rollout of multivalent meningococcal conjugate vaccines is a public well being precedence to get rid of bacterial meningitis epidemics within the African meningitis belt. Introduction into routine immunization programmes and sustaining excessive protection will probably be vital to keep away from the resurgence of epidemics.

Antibiotics for shut contacts of meningococcal circumstances, when given promptly, lower the chance of transmission. Outdoors the African meningitis belt, chemoprophylaxis is beneficial for shut contacts throughout the family. Inside the meningitis belt, chemoprophylaxis for shut contacts is beneficial in non-epidemic conditions. Ciprofloxacin is the antibiotic of selection, and ceftriaxone an alternate.

Admission to a hospital or well being centre is critical. Isolation of the affected person isn’t often suggested after 24 hours of remedy.

Acceptable antibiotic remedy have to be began as quickly as attainable. Ideally, lumbar puncture ought to be accomplished first as antibiotics could make it harder to develop micro organism from the spinal fluid. Nevertheless, blood sampling may assist to determine the trigger and the precedence is to begin remedy directly. A variety of antibiotics is used to deal with meningitis, together with penicillin, ampicillin, and ceftriaxone. Throughout epidemics of meningococcal and pneumococcal meningitis, ceftriaxone is the drug of selection.

The response to epidemics consists of acceptable case administration, energetic community-based case-finding and reactive mass vaccination of affected populations. Surveillance, from case detection to investigation and laboratory affirmation is important to the management of meningitis.

Reactive vaccination campaigns have been carried out in Zinder area, and monitoring the unfold to new areas is essential to information additional response actions, together with contemplating additional vaccine requests if acceptable. Timeliness of the reactive marketing campaign is vital, ideally inside 4 weeks of crossing the epidemic threshold.

WHO doesn’t suggest any restriction on journey and commerce to Niger on the premise of the data obtainable on the present occasion.