To assess the seroprevalence (the presence of antibodies) of Legionella among blood donors in Northeastern Australia and explore associations with demographic, environmental, and geographical factors.
Key Findings:
Total Legionella seroprevalence remained stable (32.46% in 2016 vs 32.28% in 2023).
Decrease in L. pneumophila seropositivity: SG 1-6 from 19% to 13% (p = 0.0182) and SG 7-14 from 24% to 18% (p = 0.0257).
Increase in L. longbeachae seropositivity from 1% to 3% (p = 0.0355).
L. pneumophila seroprevalence positively associated with higher rainfall and land cover, particularly in croplands and urban areas.
Interpretation:
While overall seroprevalence did not change, shifts in specific Legionella species highlight the need for ongoing monitoring and risk assessment, especially in vulnerable populations such as the elderly and immunocompromised.
Limitations:
The study did not capture cases of Pontiac fever, potentially underestimating L. longbeachae infections.
Sample collection was limited to blood donors, which may not represent the general population due to potential biases in health status and demographics.
Conclusion:
The study underscores the importance of assessing Legionella exposure risks in high-risk areas, particularly for vulnerable individuals, and calls for enhanced monitoring and preventive measures.
by Juniper Lethbridge, Wesley Freppel, Mei Fong Ho, Eloise B Skinner, Lina Rustanti, Eileen Roulis, Penny A Rudd, Helen M Faddy, Megan K Young, Lara J Herrero
