Prevalence of Pneumonic Mannheimiosis of Goats and Sheep in Asia and Africa: A Need for Vaccine Development

Pneumonic mannheimiosis is one of the most important diseases of small ruminants worldwide, in both developed and developing countries.However, limited research activities on this disease were carried out in the developing countries of Asia and Africa, despite being home to the highest numbers of sheep and goats in the world.A literature review on pneumonic mannheimiosis in Asia and Africa reveals that most countries reported the presence of this disease, involving between 25% and 60% of sheep and goats.Mannheimia haemolytica is more frequently isolated from sheep and goats than Pasteurella multocida.Almost all countries in Asia and Africa reported M. haemolytica serotype A2 as the most common isolate, followed by serotypes A6, A1, and A7, while P. multocida biotype A is the most frequently isolated Pasteurella species.However, only a few countries practice vaccination against this disease, mostly due to the unavailability of vaccines and the ineffectiveness of most commercially available vaccines.Therefore, developing multivalent or broad-spectrum vaccines that could protect against common serotypes of M. haemolytica or that protect against both Mannhemia and Pasteurella should be prioritized.