Insights into Clustering Patterns in Romania's 2020-2024 Measles Cases

Area of Science:

• Epidemiology
• Public Health
• Infectious Disease Dynamics

Background:

• Measles outbreaks exhibit clustering, with cases showing unique traits compared to non-clustered cases.
• Ongoing measles threats in Europe, particularly Romania, necessitate understanding clustering's role in disease propagation for enhanced surveillance and control.

Purpose of the Study:

• To analyze how measles case clustering affects disease transmission dynamics.
• To compare characteristics of clustered versus non-clustered measles cases.
• To assess measles transmission control effectiveness through reproduction number (R₀) analysis in large outbreaks.

Main Methods:

• National measles case data (2020-2024) were categorized into cluster (≥3 related cases) and non-cluster groups.
• Comparative analysis included vaccination status, hospitalization, age, and location.
• Basic reproduction numbers (R₀) were computed for large outbreaks (≥150 cases).

Main Results:

• Statistically significant differences were found in vaccination status, age, and hospitalization duration between clustered and non-clustered cases.
• Large measles outbreaks (≥150 cases) displayed high R₀ variability (1.0–3.92), indicating inconsistent transmission control.
• Clustering significantly influences measles transmission patterns during outbreaks.

Conclusions:

• Clustering critically impacts measles transmission dynamics, with distinct case profiles.
• Differences in vaccination, age, and hospitalization highlight the need for targeted interventions.
• Varied R₀ values in large outbreaks underscore the necessity for strengthened vaccination campaigns and improved outbreak response protocols.