Immunogenicity and Viral Shedding of Russian-Backbone, Seasonal, Trivalent, Live, Attenuated Influenza Vaccine in a Phase II, Randomized, Placebo-Controlled Trial Among Preschool-Aged Children in Urban Bangladesh.

Background: We evaluated a Russian-backbone, live, attenuated influenza vaccine (LAIV) for immunogenicity and viral shedding in a randomized, placebo-controlled trial among Bangladeshi children.

Methods: Healthy children received a single, intranasal dose of LAIV containing the 2011-2012 recommended formulation or placebo. Nasopharyngeal wash (NPW) specimens were collected on days 0, 2, 4, and 7.

Influenza A(H3N2) Virus in Swine at Agricultural Fairs and Transmission to Humans, Michigan and Ohio, USA, 2016.

In 2016, a total of 18 human infections with influenza A(H3N2) virus occurred after exposure to influenza-infected swine at 7 agricultural fairs. Sixteen of these cases were the result of infection by a reassorted virus with increasing prevalence among US swine containing a hemagglutinin gene from 2010-11 human seasonal H3N2 strains.

Evolution of highly pathogenic avian influenza (H5N1) virus populations in Vietnam between 2007 and 2010.

We report on the genetic analysis of 213 highly pathogenic avian influenza (HPAI) H5N1 viruses isolated from poultry in Vietnam between 2007 and 2010. Phylogenetic analyses of the viral genomes revealed 38 distinct viral genotypes, 29 were novel and 9 were reported in Vietnam or neighboring countries in recent years. Viruses from only six genotypes persisted beyond one season or year.

Characterization of a highly pathogenic avian influenza H5N1 virus sublineage in poultry seized at ports of entry into Vietnam.

Highly pathogenic avian influenza H5N1 virus was detected in poultry seized at two ports of entry located in Lang Son Province, Vietnam. Sequence analysis of the hemagglutinin (HA) genes from five H5N1 virus isolates and ten PCR amplicons from chicken cloacal samples revealed their close phylogenetic relationship to clade 7 H5N1 HA genes. However, these HA genes exhibited extensive genetic divergence at both the nucleotide and amino acid levels in comparison to previously described clade 7 viruses; e.

Evolution of highly pathogenic H5N1 avian influenza viruses in Vietnam between 2001 and 2007.

Highly pathogenic avian influenza (HPAI) H5N1 viruses have caused dramatic economic losses to the poultry industry of Vietnam and continue to pose a serious threat to public health. As of June 2008, Vietnam had reported nearly one third of worldwide laboratory confirmed human H5N1 infections. To better understand the emergence, spread and evolution of H5N1 in Vietnam we studied over 300 H5N1 avian influenza viruses isolated from Vietnam since their first detection in 2001.

No evidence of avian influenza A (H5N1) among returning US travelers.

We reviewed reports to the Centers for Disease Control and Prevention of US travelers suspected of having avian influenza A (H5N1) virus infection from February 2003 through May 2006. Among the 59 reported patients, no evidence of H5N1 virus infection was found; none had direct contact with poultry, but 42% had evidence of human influenza A.

Influenza-associated deaths among children in the United States, 2003-2004.

Background: Although influenza is common among children, pediatric mortality related to laboratory-confirmed influenza has not been assessed nationally.

Methods: During the 2003-2004 influenza season, we requested that state health departments report any death associated with laboratory-confirmed influenza in a U.S.

Genetic analysis of human H2N2 and early H3N2 influenza viruses, 1957-1972: evidence for genetic divergence and multiple reassortment events.

Phylogenic analysis of all gene segments of human H2N2 viruses isolated from 1957 to 1968 was undertaken to better understand the evolution of this virus subtype. Human H3N2 viruses isolated from 1968 to 1972 were also examined to investigate genetic events associated with their emergence in humans and to identify the putative H2N2 ancestral virus. All gene segments of human H2N2 viruses demonstrated divergent evolution into two distinct clades (I and II) among late H2N2 isolates.

Reassortment and evolution of current human influenza A and B viruses.

During the 2001-2002 influenza season, human influenza A (H1N2) reassortant viruses were detected globally. The hemagglutinin (HA) of these H1N2 viruses was similar to that of the A/New Caledonia/20/99 (H1N1) vaccine strain both antigenically and genetically, while their neuraminidase (NA) was antigenically and genetically related to that of recent human influenza H3N2 reference viruses such as A/Moscow/10/99. All six internal genes of the H1N2 reassortants originated from an H3N2 virus.

Intercontinental circulation of human influenza A(H1N2) reassortant viruses during the 2001-2002 influenza season.

Reassortant influenza A viruses bearing the H1 subtype of hemagglutinin (HA) and the N2 subtype of neuraminidase (NA) were isolated from humans in the United States, Canada, Singapore, Malaysia, India, Oman, Egypt, and several countries in Europe during the 2001-2002 influenza season. The HAs of these H1N2 viruses were similar to that of the A/New Caledonia/20/99(H1N1) vaccine strain both antigenically and genetically, and the NAs were antigenically and genetically related to those of recent human H3N2 reference strains, such as A/Moscow/10/99(H3N2). All 6 internal genes of the H1N2 reassortants examined originated from an H3N2 virus.