Is African swine fever also transmitted through feed?
African swine fever (ASF) has spread in Europe and other parts of the world in recent years and has developed into a panzootie (worldwide animal disease). Since the pathogen is sometimes very stable in the environment, there is a suspicion that the virus could also be transmitted via feed, water and other inanimate materials such as bedding into domestic pig herds. There is no empirical evidence of this so far, according to a joint statement from Germany's Federal Institute for Risk Assessment (BfR) and the Friedrich Loeffler Institute.
The European Food Safety Authority (EFSA) concluded there is a low risk of containing African swine fever viruses for certain feed and crops. However, there are great uncertainties due to the lack of scientific data. An international research project aims to address the unknowns.
Funded by the EFSA, the Friedrich Loeffler Institute (FLI), the Federal Institute for Risk Assessment (BfR) and the Swedish Statens Veterinärmedicinska Anstalt (SVA) are involved in the research project. Virologists from the FLI and feed experts from the BfR will investigate together with the Swedish partners the stability of ASP viruses on various feed and bedding materials under practical storage conditions.
Before the start of the study, BfR and FLI jointly evaluated previously known scientific findings on feed as a source of infection in a literature study. The influence of processing, transport and storage on possible contamination of feed with the African swine fever virus was also taken into account.
The experts concluded that in the case of processed by-products, cereals, extraction meal and compound feed, the processing steps largely inactivate any ASF viruses introduced. However, improper handling of the products could lead to recontamination with ASF viruses after production. However, if the generally applicable hygiene regulations and preventive measures for the handling and production of feed (HACCP concepts) are complied with, this route of transmission is rather unlikely. For feed that is not subjected to further treatment and is fed directly, transmission of the ASP cannot be completely ruled out.
The investigations, as planned now in the research project of the three institutions FLI, SVA and BfR, will provide urgently needed data on ASF viruses during processing and storage in feed materials for domestic pigs