Johannesburg, 4 November 2010 (IRIN) - The UN Food and Agriculture Organization (FAO) has warned Malawi, Zambia and Mozambique, which share a border with Tanzania, to step up detection of a deadly animal virus which causes Peste des petits ruminants (PPR), a contagious respiratory disease.

PPR broke out in Tanzania in early 2010, threatening over 13.5 million goats and over 3.5 million sheep.

"The Southern African countries must not vaccinate but step up alert systems," said Jan Slingenbergh, who heads FAO's Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases. "Vaccination is like throwing a blanket over the disease, it will make it hard to detect an infection."

Southern Africa has so far been spared PPR which occurs in Middle Eastern countries and parts of Central and South Asia, and has also affected western, eastern and central parts of Africa. "The disease, depending on the strength of the strain, can kill within days or not affect the infected animal at all", explained Slingenbergh.