Kathmandu, June 15: An outbreak of diarrhoea has killed 28 persons in three west Nepal districts of Baitadi, Doti and Bhajang recently, health officials said. Five persons were killed in Baitadi, 13 in Doti and 10 in Bhajang as hundreds have been stricken by the disease outbreak common during the current monsoon season. Health teams have been sent to the area to treat the victims.