New SGP/PPR combined vaccine shows promise in Africa

Peste des petits ruminants (PPR) is a highly contagious viral respiratory disease of goats and sheep causing up to 80 per cent mortality in flocks. The disease is present in West Africa, part of Central Africa (Gabon, Central African Republic), East Africa (north of the Equator), the Middle East and the Indian subcontinent including Nepal and Myanmar.

The total yearly cost of PPR is estimated to be US $874 million.

PPR and another viral disease, Sheep and Goat Pox (SGP), are often vaccinated separately and only during outbreaks. The vaccines are often controlled by governments and supplies can be limited.

Sheep pox and goat pox result from infection by sheeppox virus or goatpox virus. The disease is found in most of Africa, the Middle East and Asia.

SGP may be mild in indigenous breeds living in endemic areas, but can be fatal for newly introduced animals. Economic losses result from fall in milk production and decreased quality of hides and wool. Sheep and goat pox can limit trade and prevent the development of intensive livestock production.

The total yearly cost of the disease is estimated to be US $48 million.

Market approval is currently being sought for a new low-cost combined vaccine against PPR and SGP. While the monovalent PPR vaccine is a public good, it is expected that a multivalent PPR/SGP vaccine would not be. While emergency intervention by governments and international agencies such as FAO have been used to distribute the monovalent PPR vaccine, more sustainable systems need to be developed to make the interventions more reliable, cost-effective, consistent and timely. Bivalent vaccines are also more cost effective compared to monovalent vaccines. The vaccine cost is 40 per cent cheaper than the cost of two vaccines and protects against two diseases.

(Filmed and edited by James Karuga for Wren Media.)