Rapid and early detection of infectious diseases in pigs is important, especially for the implementation of control measures in suspected cases of African swine fever (ASF), as an effective and safe vaccine is not yet available in most of the affected countries. Additionally, analysis for swine influenza is of significance due to its high morbidity rate (up to 100%) despite a lower mortality rate compared to ASF. The wide distribution of swine influenza A virus (SwIAV) across various countries, the emergence of constantly new recombinant strains, and the danger of human infection underscore the need for rapid and accurate diagnosis. Several diagnostic approaches and commercial methods should be applied depending on the scenario, type of sample and the objective of the studies being implemented. At the early diagnosis of an outbreak, virus genome detection using a variety of PCR assays proves to be the most sensitive and specific technique. As the disease evolves, serology gains diagnostic value, as specific antibodies appear later in the course of the disease (after 7-10 days post-infection (DPI) for ASF and between 10-21 DPI for SwIAV). The ongoing development of commercial kits with enhanced sensitivity and specificity is evident. This review aims to analyse recent advances and current commercial kits utilised for the diagnosis of ASF and SwIAV.

UNASSIGNED: Swine influenza A viruses (swIAVs) are characterised by high mutation rates and zoonotic and pandemic potential. In order to draw conclusions about virulence in swine and pathogenicity to humans, we examined the existence of molecular markers and accessory proteins, cross-reactivity with vaccine strains, and resistance to antiviral drugs in five strains of H1N1 swIAVs.
UNASSIGNED: Amino acid (AA) sequences of five previously genetically characterised swIAVs were analysed in MEGA 7.0 software and the Influenza Research Database.
UNASSIGNED: Amino acid analysis revealed three virus strains with 590S/591R polymorphism and T271A substitution within basic polymerase 2 (PB2) AA chains, which cause enhanced virus replication in mammalian cells. The other two strains possessed D701N and R251K substitutions within PB2 and synthesised PB1-F2 protein, which are the factors of increased polymerase activity and virulence in swine. All strains synthesised PB1-N40, PA-N155, PA-N182, and PA-X proteins responsible for enhanced replication in mammalian cells and downregulation of the immune response of the host. Mutations detected within haemagglutinin antigenic sites imply the antigenic drift of the five analysed viruses in relation to the vaccine strains. All viruses show susceptibility to neuraminidase inhibitors and baloxavir marboxil, which is important in situations of incidental human infections.
UNASSIGNED: The detection of virulence markers and accessory proteins in the analysed viruses suggests their higher propensity for replication in mammalian cells, increased virulence, and potential for transmission to humans, and implies compromised efficacy of influenza vaccines.

Modelling in epidemiology can be used for parameter estimation, understanding infectious process or control strategies evaluation, and is based on a mathematical model representing the infectious process derived from the SIR model (susceptible-infectious-removed). This model is further adapted to the disease under study with additional health statuses to represent more precisely the characteristics of the infectious agent and to couple the infection dynamics with the population dynamics of the studied system. This adaptation is documented by descriptive and analytic epidemiological studies to obtain a model representing the infectious process in a realistic way. Risk assessment and/or evaluation of control strategies can be proposed by the model simulation. The use of a modelling approach to understand the determinisms of a viral infectious process within a structured animal population is further illustrated by the example of swine influenza A viruses persistence in pig farms. The model set up to this aim is used to better understand the mechanisms related to viruses persistence within the herd and identify potential control measures that could be applied in farm conditions.