Legionnaires' disease surveillance: England and Wales, 1995

Area of Science:

• Epidemiology
• Infectious Diseases
• Public Health Surveillance

Background:

• Legionnaires' disease remains a significant public health concern, with cases often linked to travel or community acquisition.
• Surveillance data provides crucial insights into disease trends, risk factors, and diagnostic methods.

Purpose of the Study:

• To analyze the epidemiology of legionnaires' disease in England and Wales during 1995.
• To identify sources of infection, including travel, hospital stays, and community outbreaks.
• To assess trends in diagnostic methods and their implications.

Main Methods:

• Retrospective analysis of legionnaires' disease case reports submitted to the PHLS Communicable Disease Surveillance Centre in 1995.
• Categorization of cases based on presumed acquisition source (travel, hospital, community) and occurrence (sporadic, outbreak).
• Evaluation of diagnostic methods, including culture and urinary antigen detection.

Main Results:

• 160 cases of legionnaires' disease were reported, with a 13% mortality rate.
• Travel-associated cases constituted the largest proportion (56%), followed by community-acquired (41%) and hospital-acquired (3%) cases.
• A decline in culture-based diagnosis was observed, with a corresponding increase in urinary antigen detection for Legionella pneumophila serogroup 1.

Conclusions:

• Travel remains the primary risk factor for legionnaires' disease, highlighting the importance of travel-related prevention strategies.
• The decrease in diagnostic culture rates is a concern, potentially impacting accurate identification and source tracking.
• Continued surveillance is essential for monitoring disease patterns and informing public health interventions.