BACKGROUND The influenza viruses circulating in animals sporadically transmit to humans and pose pandemic threats. Animal models to evaluate the potential public health risk potential of these viruses are needed. METHODOLOGY/PRINCIPAL FINDINGS We investigated the guinea pig as a mammalian model for the study of the replication and transmission characteristics of selected swine H1N1, H1N2, H3N...

The emergence of a swine influenza virus (H1N1) pandemic strain earlier this year prompted a huge worldwide effort to produce swine flu vaccines in time for the winter flu season. Justine Davies reports.

The rapid outbreak of the highly pathogenic A/H5N1 avian influenza virus among domestic birds and its transmission to humans have induced world-wide fears of a new influenza pandemic. If a human-trophic strain of A/H5N1 is replicated in domestic animals, it might have high transmissivity and pathogenicity to humans. If the misassembling of both avian and swine influenza viruses occur in the sam...

BACKGROUND Pigs are mixing vessels for influenza viral reassortment, but the extent of influenza transmission between swine and humans is not well understood. OBJECTIVES To assess whether occupational exposure to pigs is a risk factor for human infection with human and swine-adapted influenza viruses. METHODS UK pig industry workers were frequency-matched on age, region, sampling month, and...

The emergence and transition to pandemic status of the influenza A(H1N1)A(H1N1)pdm09) virus in 2009 illustrated the potential for previously circulating human viruses to re-emerge in humans and cause a pandemic after decades of circulating among animals. Within a short time of the initial emergence of A(H1N1)pdm09 virus, novel reassortants were isolated from swine. In late 2011, a variant (v) H...

BACKGROUND The 2009 H1N1 pandemic viruses are genetically similar to A/New Jersey/76 H1N1 virus (NJ/76), the strain selected for the 1976 "swine flu" vaccines. Approximately 45 million people in the United States were vaccinated against NJ/76 30 years ago, but the impact of this nationwide immunization on the current pandemic is largely unknown. METHODS Archived human serum samples collected ...

The emergence of the unique H1N1 influenza A virus in 2009 resulted in a pandemic that has spread to over 200 countries. The constellation of molecular factors leading to the emergence of this strain is still unclear. Using a computational approach, we identified molecular determinants that may discriminate the hemagglutinin protein of the 2009 human pandemic H1N1 (pH1N1) strain from that of ot...

In this study, the full-genome sequence of a novel reassortant H1N1 swine influenza virus (SIV) is reported. The isolate has a hemagglutinin (HA) gene of the pandemic H1N1 influenza virus, but it carries the seven genome segments of the avian-origin H1N1 SIV currently circulating in European pig farms.

After multiple discrete introductions of influenza A(H1N1)pdm09 virus into Sri Lanka, the virus was transmitted among humans, then swine. The spread of virus between geographically distant swine farms is consistent with virus dispersal associated with a vehicle used for swine transportation, although this remains unproven.

We evaluated 49 swine industry workers and 79 nonexposed controls for antibodies to swine influenza viruses. Multivariate modeling showed that workers who seldom used gloves (odds ratio [OR] 30.3) or who smoked (OR 18.7) most frequently had evidence of previous H1N1 swine virus. These findings may be valuable in planning for pandemic influenza.