The World Health Organization speculated that a mass poisoning event was behind the deaths of 60 people. But African experts suspect a more mundane cause.

The outbreak began in January, with 419 cases recorded so far, and comes after another mystery illness killed 143 in December

An unknown disease that poses a ‘significant public health threat’ has already killed more than 50 people. The disease started on January 21 in the village of Boloko, in the Democratic Republic of Congo ( DRC ), after three children ate a dead bat, according to the World Health Organisation (WHO) Africa office.