# Investigation of a bacterial meningitis cluster in a refugee settlement, Obongi District, Uganda, March 2023

## TL;DR

A cluster of bacterial meningitis caused by Neisseria meningitidis serogroup C was identified in a Ugandan refugee settlement, primarily affecting unvaccinated children.

## Contribution

The study identifies a meningococcal cluster in a refugee settlement and highlights the lack of vaccination as a key risk factor.

## Key findings

- 25 meningitis cases, including 2 deaths, were identified in Palorinya Refugee Settlement between December 2022 and May 2023.
- 76% of affected individuals were under 18 years old, and none had been vaccinated against serogroup C.
- No epidemiological link was found between the cases, indicating potential community-wide transmission.

## Abstract

On 6 March 2023, Neisseria meningitidis serogroup C was isolated from a cerebral spinal fluid sample from Obongi District, Uganda. This sample was one of many from patients who were presenting with fever, convulsions, and altered consciousness. We investigated to determine the scope of the meningitis cluster, identify risk factors of contracting meningitis, and inform control measures. We reviewed medical records, conducted active community case finding, and conducted key informant interviews in the affected communities to identify cases and factors associated with contracting meningitis. We analysed case data by person, place, and time. Between 22 December 2022 and 1 May 2023, 25 cases with 2 deaths of bacterial meningitis occurred in Palorinya Refugee Settlement, Obongi District. Of these, 4 were laboratory-confirmed with Neisseria meningitidis serogroup C, 6 were probable cases, and 15 were suspected cases. Most (76%) of case-patients were <18 years old with a median age of 12 years (range 1-66 years). None of the case-patients was vaccinated against Neisseria meningitidis serogroup C. Each case-patient was from a different household and there was no epidemiological link between any of the cases. This meningococcal meningitis cluster caused by Neisseria meningitidis serogroup C occurred among non-vaccinated persons mostly aged <18 years in Palorinya Refugee Settlement. We recommended vaccination of at-risk persons.