Epidemiology and Economic Impact of Rift Valley Fever: A Brief Review

Abstract

Rift Valley fever (RVF) is a disease of domestic ruminants, caused by an arbovirus belonging to the Phlebovirus genus Bunyaviridae family, a group of enveloped single-stranded RNA viruses. It is a mosquito-borne viral zoonotic disease with a significant global threat in devastating economic losses at household and national levels and human health. The lack of efficient prophylactic and therapeutic measures makes infection a serious public health concern. This review was made to organize information on the epidemiology, management, and economic impacts of RVF. The disease is characterized by a sudden onset of abortions and high neonatal mortality in ruminants and with self-limiting infection in humans. Many outbreaks are associated with persistent high rainfalls, competent mosquito vectors, and susceptible vertebrate species. The transmission of RVF is primarily by the bites of the mosquitoes. Human acquires the infection by contact with the infected animals and insect bites. Diagnosis is confirmed by RT-PCR, culture, serology, and histopathology of the liver. Vaccination, destruction of vectors, movement control, surveillance, and sentinel herd monitoring can help in the control of RVF. Because of the extended geographical range of the virus, the probability of emergence in new areas e.g. East African countries is likely to increase in recent years. By considering cyclical occurrence, forecasting high precipitation events using spatiotemporal epidemiological investigation for up to 4 months that may lead to explosive outbreaks is better. Improving knowledge among herders leads to better practices of management programs to benefit most from the livestock industry and safeguard public health.