UK: Search for enzootic pneumonia vaccine continues

The research will specifically focus on Mycoplasma hyopneumoniae (M. hyo), the causative agent of the disease, and aim to progress vaccine development.

M. hyo is present in 80% of UK pig herds, which can result in a 16% reduction of growth and a 14% reduction in feed conversion in pigs. This therefore, is not only a welfare issue for pigs but can significantly increase production costs for farmers.

Transmission during lactation

Additionally, piglets are considered free from M. hyo at birth and with close contact between infected and susceptible pigs the main route of transmission is often during lactation when piglets are first exposed. This places piglets under enormous risk of developing the respiratory disease as well as infection from secondary pathogens, according to the RVC.

There are currently no commercial vaccines available that would prevent initial infection, and while M. hyo is susceptible to a variety of antibiotics, their use needs to be reduced to avoid overuse and the occurrence of multi-drug resistant strains.

An RVC spokesperson commented, “Therefore, a priority for the RVC team is to develop vaccines that confer protective immunity and reduce transmission. As the project is in the early stages, we are unable to share too much information at this time however our approach will not be based on a classical live-attenuated or inactivated vaccine. Instead, it will use results of a TraDis library that has identified essential genes.”

M. hyo survival in pigs

Building on previous research which identified the genes that are essential for the survival of the pathogen in pigs and isolated strains of bacteria from UK pigs, this new research project will discover the bacterial genes that are necessary for disease as a basis for the development of better vaccines to prevent the circulation of enzootic pneumonia.

Professor Dirk Werling, professor of molecular immunology at the RVC, said: “Infection of M. hyo is a really debilitating disease in pigs that causes huge economic losses for farmers. I am very pleased that we will be able to continue working with a pharmaceutical partner to develop a new vaccine using state-of the-art technologies.”