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Microscopy-based Assays for High-throughput Screening of Host Factors Involved in Brucella Infection of Hela Cells
Published on: August 5, 2016
A large exposure to Brucella melitensis in a diagnostic laboratory
I-C Sam1, R Karunakaran, A Kamarulzaman
1Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. jicsam@ummc.edu.my
Background:
Brucella species are easily transmitted by aerosols and can be acquired in the laboratory.
Aim:
To report the management of a large exposure to Brucella melitensis that occurred over six days in a hospital diagnostic laboratory.
Methods:
Fifty-one exposed staff were managed according to Centers for Disease Control and Prevention guidelines. A further 96 non-exposed laboratory staff were tested for seroprevalence. Testing was carried out using the Brucella sp. serum agglutination test.
Findings:
Twenty-seven people had high-risk exposure and 24 had low-risk exposure. High-risk staff were offered post-exposure prophylaxis. Twelve (44.4%) agreed to this, of whom eight (66.7%) completed the course. Overall compliance with serological follow-up at baseline, 2, 4, 6 weeks and 8 months was 45.9%. Despite this poor compliance there were no clinical brucellosis cases and no seroconversion in the 47.1% of staff tested at 8 months. Brucella sp. seroprevalence among all staff tested was 3/147 (2.0%).
Conclusion:
Lack of experience with Brucella spp. and lack of policies for handling potentially hazardous organisms contributed to this prolonged exposure. As compliance with current recommendations may be poor, the optimum frequency of serological follow-up and target groups for prophylaxis should be reassessed. Laboratories in low- or non-endemic areas must prepare for potential isolation of Brucella spp. The impact of human brucellosis in Malaysia requires further study.
Insights
A large Brucella melitensis exposure in a hospital lab led to management of 51 staff. Despite poor compliance with follow-up and prophylaxis, no clinical brucellosis or seroconversion occurred, indicating effective management strategies for laboratory-acquired infections.
Area of Science:
- Occupational Health
- Infectious Disease Epidemiology
- Laboratory Safety
Background:
- Brucella species pose an aerosol transmission risk, particularly in laboratory settings.
- Hospital diagnostic laboratories require robust protocols for handling potentially hazardous biological agents like Brucella melitensis.
Observation:
- A six-day exposure event involving Brucella melitensis occurred in a hospital diagnostic laboratory.
- Fifty-one laboratory staff were identified as exposed, with 27 classified as high-risk and 24 as low-risk.
- Post-exposure prophylaxis was offered to high-risk staff, with limited uptake and completion rates.
Findings:
- Despite low compliance with serological follow-up (45.9%) and prophylaxis (44.4% uptake, 66.7% completion), no clinical brucellosis cases were observed.
- No seroconversion was detected among the 47.1% of staff tested at 8 months.
- The overall seroprevalence of Brucella species among all tested staff was 2.0% (3/147).
Implications:
- The study highlights potential deficiencies in laboratory experience and policies for handling hazardous organisms, contributing to prolonged exposure.
- Poor compliance with current recommendations necessitates a reassessment of optimal serological follow-up frequency and prophylaxis target groups.
- Laboratories, especially in non-endemic areas, must be prepared for Brucella spp. isolation, and the impact of human brucellosis warrants further investigation.
