Senegal reports 17 deaths in Rift Valley Fever outbreak

DAKAR (Reuters) -Senegal has recorded 17 deaths from Rift Valley Fever (RVF), a health ministry official said on Thursday, apparently the deadliest outbreak in decades.

The 119 cases were concentrated in northern Senegal, a major livestock-producing region, heightening concern about further spread, said Dr Boly Diop, the ministry’s head of RVF surveillance.

RVF, a viral disease that primarily affects livestock, is largely spread to animals via mosquitoes, according to the World Health Organization, which says no human-to-human transmission has been documented. 

Humans typically become infected through mosquito bites or contact with blood, body fluids or tissues of infected animals, according to the Africa Centres for Disease Control and Prevention.

RVF has been endemic in northern Senegal since the 1980s, Dr Merawi Aragaw Tegegne, an epidemiologist at Africa CDC, told a weekly press briefing on Thursday.

“It has been becoming more frequent these days across Africa, and these various diseases are closely related with climate change and extreme weather events,” Tegegne said.

“If you see torrential rain with quick floods, then sunny days, expect RVF in the coming days with favourable conditions for the vectors,” he said.

The current outbreak was declared on September 21, according to Africa CDC, noting the response has been hampered by low community awareness, a weak early warning system and late detection of cases.

An RVF epidemic in 1987-88 killed more than 200 people in Senegal and Mauritania. Since then, Senegal has reported only minor outbreaks.

“This is the first time Senegal has counted so many people affected,” Diop said.

RVF can spread to humans during slaughter and butchering, animal births, veterinary procedures and disposal of carcasses or fetuses, putting herders, farmers, slaughterhouse workers and veterinarians at higher risk, according to the WHO.

Most human infections are mild and cause few or no symptoms, the WHO said. It said severe cases take several forms, including an ocular form that can cause loss of vision and a haemorrhagic form that has a 50% case fatality rate.

(Reporting by Diadie Ba; Writing by Ayen Deng Bior; Editing by Robbie Corey-Boulet and David Gregorio)