The work was funded by a grant to SGUL by the Bill & Melinda Gates Foundation and the Wellcome Trust, under the Grand Challenges in Global Health Initiative and by a grant to Harvard Medical School by the Bill & Melinda Gates Foundation’s Collaboration for AIDS Vaccine Discovery/Comprehensive Antibody–Vaccine Immune Monitoring Consortium, grant number 38619. We thank Professors Ralf Wagner and Hans Wolf, University of Regensburg and GENEART AG for the p97CN54-expressing plasmid and Mark Robinson and William Elsley, NIBSC for assistance. The study was integrated with efforts to standardise HIV vaccine development through the EUROPRISE Network of Excellence on Microbicides and Vaccines.

MPC

and PFM are supported by the Sir Joseph Hotung Trust. “
“In Bortezomib mw April 2009 a new influenza A/H1N1 virus strain was detected in two GDC-0068 children in Southern California, both suffering from respiratory disease [1]. Full sequence analysis showed that this new influenza strain, currently named “pandemic (H1N1) 2009” (H1N1v), is likely a reassortant between North American and Eurasian swine influenza strains [2] and [3]. Unlike most other introductions of swine influenza strains in the human population, this strain was successful in human-to-human transmission. The virus spread quickly to other countries and continents and finally, on the 11th June 2009, the WHO declared this outbreak to be a pandemic, the first one since 1968 (Hong Kong flu). On 28 April 2009, the Canadian Food Inspection Agency became involved Parvulin in the first field infection of swine with this H1N1v [4]. Introduction of the virus through an infected human was suspected, but could not be proven. On the 25th June, a second swine herd, in Argentina, was reported to the World Organization for Animal Health (OIE) as being infected [5]. Also in this case, introduction through infected humans was suspected, but could not be confirmed. In both cases the clinical symptoms in the pigs were rather mild and recovery of the pigs was

uneventful. Many more such cases in swine herds have since been detected, in countries all over the world. The susceptibility of pigs to this particular virus strain has been confirmed in several experimental studies [6], [7] and [8]. Clinical symptoms in pigs were shown to be similar to those caused by endemic swine influenza strains. It was also shown that virus transmission to susceptible pigs, at least those naïve for antibodies against any swine influenza viruses, readily occurs. Whether the H1N1v is able to outcompete endemic H1N1 and/or H1N2 strains, or whether it would be able to co-exist with these endemic strains in swine, is as yet unknown. In such cases pigs may become a reservoir from which repeated introductions into the human population could occur.