African swine fever virus rapid detection assays evaluation

African swine fever (ASF) is a highly fatal disease of pigs. It is a threat to the pig industry as it lowers production and significantly impacts on livelihoods of small-scale producers, while outbreaks continue to be reported in Africa, Europe, Asia, and more recently in the Caribbean. There are no globally available treatment nor commercial vaccines against ASF.

The most effective measures to control the disease include early detection using rapid diagnostic test and separation of infected animals from healthy ones, usually by culling/disposing affected pigs.

Diagnostic of ASF includes from clinical diagnostics to the identification of the agent and serological tests, according to the World Organization for Animal health (WOAH). Clinical diagnostics is often challenging since ASF shares common clinical signs with other pig diseases (e.g. classical swine fever) in its acute form; and for the chronic forms subtle clinical signs can be overlook. The lesion identification has the limitation of post-mortem diagnostics and not possible to implement in non-death pigs. Laboratory diagnostics are more accurate, including the dentification of the viral particle by means of isolation of the virus from animal samples, hemadsorption tests, fluorescent antibody test; or the detection of the viral genome by polymerase chain reaction (PCR). Serological tests are also useful to detect previous exposure to the virus. They include Enzyme-linked immunosorbent assay (ELISA), indirect fluorescent antibody (IFA) test and immunoblotting. However, even if accurate, all these laboratory tests pose the same problem; they are difficult to implement in the field where infrastructures and human expertise are limited or non-existent, as it is the case in countries where the disease is endemic. The time to get results is also key for the control of ASFV in the field and all the mentioned tests do not provide immediate results.