# Epidemiology of invasive meningococcal disease in the United States: review of recent data and identified risk factors

## TL;DR

This paper reviews the spread of invasive meningococcal disease in the U.S., showing a rebound after the pandemic and identifying key risk groups.

## Contribution

The study provides updated epidemiological data on IMD in the U.S. from 2016 to 2024, including trends during and after the pandemic.

## Key findings

- IMD cases dropped during the pandemic but increased again after 2021.
- Serogroup C was the most common in 2022, followed by serogroup B.
- High IMD incidence was observed in infants, Black populations, and people experiencing homelessness post-pandemic.

## Abstract

Tracking the spread of invasive meningococcal disease (IMD) in the United States is important for identifying risk factors and devising public health strategies to prevent infection.

The epidemiology of IMD in the United States before, during, and after the COVID-19 pandemic (2016–2024) was assessed using surveillance data from the National Notifiable Diseases Surveillance System (NNDSS) and the Enhanced Meningococcal Disease Surveillance program (EMDS).

IMD case numbers declined during the pandemic (2020–2021) to 208 in 2021 but rebounded to 312 in 2022 and have continued to increase through 2024 (provisionally 477 cases). In 2022, serogroup C was the predominant serogroup (107 cases), followed by serogroup B (61 cases). Except during the pandemic, IMD cases were higher among those attending versus not attending college. During and after the pandemic, groups with the highest IMD incidence were those <1 year of age (range, 0.38–0.56 cases per 100,000 persons) and within the Black population (range, 0.09–0.19 cases per 100,000 persons). The percentage of IMD cases occurring after the pandemic in men who have sex with men and those with HIV increased substantially from during the pandemic. The percentage of IMD cases that occurred among people experiencing homelessness (PEH) was relatively high, ranging from 2.4–6.3%.

The data indicate a rebound in IMD after the COVID-19 pandemic, highlighting the importance of strengthening surveillance and vaccination among high-risk populations.