Risk factors associated with human Rift Valley fever infection: systematic review and meta‐analysis

OBJECTIVE: To identify risk factors for human Rift Valley fever virus (RVFV) infection. METHODS: A systematic review identified 17 articles reporting on 16 studies examining risk factors for RVFV. Pooled odds ratios (pOR) were calculated for exposures examined in four or more studies. RESULTS: Being male [pOR = 1.4 (1.0, 1.8)], contact with aborted animal tissue [pOR = 3.4 (1.6, 7.3)], birthing an animal [pOR = 3.2 (2.4, 4.2)], skinning an animal [pOR = 2.5 (1.9, 3.2)], slaughtering an animal [pOR = 2.4 (1.4, 4.1)] and drinking raw milk [pOR = 1.8 (1.2, 2.6)] were significantly associated with RVF infection after meta-analysis. Other potential risk factors include sheltering animals in the home and milking an animal, which may both involve contact with animal body fluids. CONCLUSIONS: Based on the identified risk factors, use of personal protective equipment and disinfectants by animal handlers may help reduce RVFV transmission during outbreaks. Milk pasteurisation and other possible preventive methods require further investigation.