Legionella pneumophila contamination in central air-conditioning systems of public places in China：a meta-analysis
FANG Zisi1, LIAO Hui1, ZHOU Xiaocong1, XU Hong2
1. School of PublicHealth, Zhejiang University of Traditional Chinese Medicine, Hangzhou, Zhejiang 310053, China; 2. Hangzhou Center for Disease Control and Prevention, Hangzhou, Zhejiang 310021, China
Abstract：Objective To systematically evaluate the detection of Legionella pneumophila in central air-conditioning systems of public places in China, so as to provide insights into the management of L. pneumophila contamination. Methods The publications pertaining to L. pneumophila contamination in central air-conditioning systems of public places in China were searched in international and national databases, including CNKI, Wanfang Data, CBM, PubMed and Web of Science from January 1, 2010 to December 31, 2022. The publication quality was evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology. A meta-analysis was performed using the software Stata version 16.0. The pooled detection of L. pneumophila and its 95%CI were estimated. The publication bias was evaluated using Begg's test, and sensitivity analysis was performed with the leave-one-out evaluation for assessment of the robustness of the outcomes. Results A total of 742 publications were initially searched, and 29 publications were finally included, all of which were cross-sectional studies. The publications included 10 high-quality and 19 moderate-quality studies covering 6 160 samples, and the pooled detection of L. pneumophila was 17.20% (95%CI: 12.80%-21.90%). Subgroup analysis showed a higher detection rate of L. pneumophila in cooling water (21.80%) than in condensed water (5.50%) (P<0.01). According to the criteria defined in Hygienic Specification of Central Air-conditioning Ventilation System in Public Buildings (2006 version), the detection of L. pneumophila was 23.30%, which was higher than the detection (13.20%) according to the Hygienic Specification of Central Air-conditioning Ventilation System in Public Buildings (WS 394-2012) (P<0.05). The detection of L. pneumophila did not vary in place, region or sample (P>0.05). Begg's test showed no significant publication bias, and sensitivity analysis showed robustness of the results. Conclusions The detection of L. pneumophila ranges from 12.80% to 21.90% in central air-conditioning systems of public places in China. Health and environmental protection sectors need to improve the monitoring of L. pneumophila contamination in central air-conditioning systems of public places.
