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In this study, we sought to examine whether evidence existed suggesting that pigs were being infected with the novel H7N9 avian influenza virus. From November 2012 to November 2013, blood was drawn from 1560 pigs from 100 large farms in 4 provinces of eastern China. Many of these pigs were in close proximity to wild birds or poultry. Swine sera were studied using hemagglutinin inhibition (HI) assays and enzyme-linked immunosorbent assays (ELISAs) against the H7 antigen derived from the emergent H7N9 avian influenza virus (AIV). Only 29 of the 1560 samples had HI titers of 1:20 when using the H7N9 AIV antigens, and none of the 29 (H7N9 AIV) HI-positive samples were positive when using ELISA, indicating that no samples were positive for H7N9. The negative results were also verified using a novel competitive HA-ELISA. As pigs have been shown to be infected with other avian influenza viruses and as the prevalence of novel influenza A viruses (e.g., H7N9 AIV) may be increasing among poultry in China, similar seroepidemiological studies of pigs should be periodically conducted in the future. [ABSTRACT FROM AUTHOR]

Abstract: Bovine viral diarrhea virus (BVDV) infects both domestic and wild animals, causing substantial economic losses. In order to investigate possible infection in Bactrian camels in Western China, a total of 56 blood samples were collected from clinically healthy Bactrian camels and tested for BVDV antigens and antibodies using antigen capture enzyme-linked immunosorbent assay (ELISA) and virus neutralization test. The antigen-positive samples (n =17) were further tested for viral nucleic acids by species-specific real-time RT-PCR assays, which showed presence of BVDV-1, but not BVDV-2 nor atypical bovine pestivirus, in the camel samples. Twelve non-cytopathogenic viruses were isolated and genetically typed by sequencing of the 5′untranslated region (5′UTR) and Npro coding sequences. Phylogenetic analysis divided the isolates into six known subgenotypes: BVDV-1a, BVDV-1b, BVDV-1c, BVDV-1m, BVDV-1o, BVDV-1p and a putative subgenotype, BVDV-1q. This study provides, for the first time, serological and molecular evidence for natural infection of Bactrian camels in Western China with highly divergent BVDV-1 strains. Further investigations are needed to elucidate the possible roles of Bactrian camels in the epidemiology of BVD in Western China. [Copyright &y& Elsevier]