The burden of meningococcal meningitis in the African Meningitis Belt, from 2009 to 2014: a trend analysis

Childhood meningitis in rural Gambia: 10 years of population-based surveillance

Background

The introduction in many countries of conjugate vaccines against Haemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis has led to significant reductions in acute bacterial meningitis (ABM) in children. However, recent population-based data on ABM in sub-Saharan Africa are limited.

Methods

Population-based surveillance for meningitis was carried out in a rural area of The Gambia under demographic surveillance from 2008 to 2017, using standardised criteria for referral, diagnosis and investigation. We calculated incidence using population denominators.

Results

We diagnosed 1,666 patients with suspected meningitis and collected cerebrospinal fluid (n = 1,121) and/or blood (n = 1,070) from 1,427 (88%) of cases. We identified 169 cases of ABM, 209 cases of suspected non-bacterial meningitis (SNBM) and 1,049 cases of clinically suspected meningitis (CSM). The estimated average annual incidence of ABM was high at 145 per 100,000 population in the <2-month age group, 56 per 100,000 in the 2–23-month age group, but lower at 5 per 100,000 in the 5–14-year age group. The most common causes of ABM were Streptococcus pneumoniae (n = 44), Neisseria meningitidis (n = 42), and Gram-negative coliform bacteria (n = 26). Eighteen of 22 cases caused by pneumococcal serotypes included in PCV13 occurred prior to vaccine introduction and four afterwards. The overall case fatality ratio for ABM was 29% (49/169) and was highest in the <2-month age group 37% (10/27). The case fatality ratio was 8.6% (18/209) for suspected non-bacterial meningitis and 12.8% (134/1049) for clinically suspected meningitis cases.

Conclusions

Gambian children continue to experience substantial morbidity and mortality associated with suspected meningitis, especially acute bacterial meningitis. Such severely ill children in sub-Saharan Africa require improved diagnostics and clinical care.

Carriage prevalence of Neisseria meningitidis in China, 2005-2022: a systematic review and meta-analysis

Introduction

Neisseria meningitidis (Nm) is a major cause of meningitis and septicemia. Most people are infected with latent infections or are carriers. We aimed to estimate the carriage prevalence of Nm in China.

Methods

We did a systematic review of published work to assess the prevalence of meningococcal carriage in China. The quality assessment was conducted by the risk of bias tool according to Damian Hoy’s study. We estimated pooled proportions of carriage and its 95% confidence interval (95% CI) using fixed effect model for studies with low heterogeneity and random effect model for studies with moderate or high heterogeneity. Subgroup analyses were also conducted by region and age group.

Results

In total, 115 studies were included. The quality evaluation grades of all included documents were medium or high grade. The weighted proportion of carriage was 2.86% (95% CI: 2.25–3.47%, I²: 97.7%, p = 0). The carriage prevalence of Nm varied between provinces, ranged from 0.00% (95% CI: 0.00–0.66%) to 15.50% (95% CI: 14.01–16.99%). Persons aged 15 years and older had the highest carriage 4.38% (95% CI: 3.15–5.62%, I2: 95.4%, p < 0.0001), and children under 6 years of age had the lowest carriage 1.01% (95% CI: 0.59–1.43%, I2: 74.4%, p < 0.0001). In positive carriers, serogroup B (41.62%, 95% CI: 35.25–48.00%, I²: 98.6%, p = 0) took up the highest proportion, and serogroup X (0.02%, 95% CI: 0.00–0.09%, I²: 0.00%, p = 1) accounted for the lowest proportion.

Conclusion

The meningococcal carriage in China was estimated low and varied by region and age group. Understanding the epidemiology and transmission dynamics of meningococcal infection in insidious spreaders is essential for optimizing the meningococcal immunization strategies of the country.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07586-x.