Laboratory-Acquired Malaria Infections: Exposure Mechanisms and Biosafety Implications

Background: Laboratory-acquired infections (LAIs) with Plasmodium species are uncommon but represent a documented occupational hazard in insectaries, research laboratories, and clinical diagnostic settings. As malaria research expands, understanding historical and contemporary laboratory exposures is important for biosafety practice. Methods: We reviewed published reports of laboratory-acquired malaria, including a historical series summarized by Herwaldt (1920–1990) and confirmed cases identified through the ABSA International LAI Database and national surveillance reports (1968–2012). Cases were analyzed to assess the species involved, exposure mechanisms, clinical outcomes, and biosafety implications. Results: Approximately 38 laboratory-acquired malaria cases have been reported, although the exact number is difficult to determine due to overlapping reporting. Infections involved Plasmodium falciparum , P. vivax , and P. cynomolgi . Vector-borne transmission from experimentally infected Anopheles mosquitoes accounted for most cases; however, parenteral and non-intact skin exposures to parasitized blood also resulted in infection. All reported cases were symptomatic. A minority of P. falciparum infections were severe, although no fatalities were documented in the reviewed series. The median incubation period following nonvector exposure was ∼12.5 days. Conclusions: Laboratory-acquired malaria remains a preventable occupational risk. Effective mitigation requires integrated vector containment, sharps safety, appropriate personal protective equipment, engineering controls, medical surveillance, and a strong institutional biosafety culture in both insectary and in vitro research environments.