Laboratory-acquired infection in clinical laboratories and the incidence rate after Brucella exposure risk events: a systematic review and meta-analysis.

Background: This study aimed to summarize the characteristics of laboratory-acquired infections (LAIs) and review exposure incidents in clinical laboratories. Additionally, a meta-analysis was conducted to estimate post-exposure incidence rates and evaluate the efficacy of post-exposure prophylaxis (PEP) following Brucella exposures.

Methods: A systematic search across databases including PubMed, Embase, Web of Science, CNKI, Wanfang, CMB, and the ABSA LAI database was conducted to extract relevant literature published during January 1, 1990, to August 31, 2023. Case reports and laboratory exposure risk events in clinical laboratories were included. Negative-binomial regression was used to estimate the relative increase in reported numbers per year of LAIs. A meta-analysis was performed to estimate the incidence rate (IR) of LAIs among exposed laboratory personnel after Brucella exposure risk events.

Findings: A total of 164 LAIs were reported in hospital laboratories. Negative-binomial regression analysis indicated no significant decline in annual LAIs reports (relative risk and 95% CI: 0.9834 [0.9667,1.0001], P value: 0.052). Most LAIs (68.3%) occurred during routine work, with only 9.8% linked to laboratory unintended exposure. The leading pathogens were Brucella (55.5%), Neisseria meningitidis (7.3%), and Shigella sonnei (5.5%). The proportion of LAIs caused by Brucella in developing countries was higher than that in developed countries (72.4% vs. 48.7%). The meta-analysis revealed that the incidence rate for Brucella-related LAIs among laboratory personnel was calculated to be 60 per 100,000 laboratory personnel. Laboratory personnel exposed to high-risk Brucella incidents faced a notably elevated infection risk, estimated at 80 per 100,000 laboratory personnel. Among higher-risk Brucella exposures, laboratory personnel who did not receive PEP experienced a 6.33 times higher risk of infection compared to those who did. The attributable fraction associated with the absence of PEP was 84.2%.

Conclusions: Clinical laboratory personnel remain at infection risk, with no reduction in reported LAI cases, mainly resulting from Brucella acquisitions. PEP proved effective against high-risk Brucella exposures.