The immunogenicity and protective efficacy of the site-specific mutants of A/WSN/33 (H1N1) strain of the influenza virus were compared with the similar characteristics of the cold-adapted (CA) reassortant obtained by crossing A/WSN/33 strain and CA A/ Krasnodar/101/35/59 (H2N2) strain of the influenza virus under homologous and heterologous control infection. The site-specific mutants had ts-mu...

We describe 3 cases of acute gastroenteritis in healthy infants after vaccination with RotaTeq, shedding a G1P[8] human-bovine double reassortant rotavirus in stools. Such a double reassortant virus appears stable in vitro and may explain diarrheal symptoms in a small percentage of RotaTeq recipients, and might also be transmitted to contacts in the environment.

Zoonotic infections with swine influenza A viruses are reported sporadically. Triple reassortant swine influenza viruses have been isolated from pigs in the United States since 1998. We report a human case of upper respiratory illness associated with swine influenza A (H1N1) triple reassortant virus infection that occurred during 2005 following exposure to freshly killed pigs.

Pandemic influenza requires interspecies transmission of an influenza virus with a novel hemagglutinin (HA) subtytpe that can adapt to its new host through either reassortment or point mutations and transmit by aerosolized respiratory droplets. Two previous pandemics of 1957 and 1968 resulted from the reassortment of low pathogenic avian viruses and human subtypes of that period; however, condi...

Pandemic H1N1/2009 influenza virus, derived from a reassortment of avian, human, and swine influenza viruses, possesses a unique gene segment combination that had not been detected previously in animal and human populations. Whether such a gene combination could result in the pathogenicity and transmission as H1N1/2009 virus remains unclear. In the present study, we used reverse genetics to con...

Thirty-five human influenza A(H5N1) cases were reported in Cambodia during 2013-2014 after emergence of a clade 1.1.2 reassortant virus. We tested 881 villagers and found 2 cases of pauci- or asymptomatic infection. Seroprevalence after emergence of the reassortant strain (0.2%) was lower than the aggregate seroprevalence of 1.3% reported in earlier studies.

A cold-adapted (ca) influenza B reassortant virus vaccine that contained the six internal RNA segments from influenza B/Ann Arbor/1/66 ca virus and the neuraminidase and hemagglutinin genes from wild-type influenza B/Texas/1/84 virus was evaluated in children ranging in age from 8 months to 14 years. The children were vaccinated intranasally with doses ranging from 10(3.2) to 10(6.2) 50% tissue...

The primary vector species for bluetongue virus (BTV) in the United States, Culicoides variipennis, was orally infected with BTV serotype 10, BTV serotype 17, or a mixture of the two viruses. The recovery of virus from the infected flies was low following a period of extrinsic incubation. Electrophoretic analysis of progeny virus from singly infected flies revealed that only the parental electr...

Genetic exchange by recombination, or reassortment of genomic segments, has been shown to be an important process in RNA virus evolution, resulting often in important phenotypic changes affecting host range and virulence. However, data from numerous systems indicate that reassortant or recombinant genotypes could be selected against in virus populations and suggest that there is coadaptation am...

In 2009, a novel H1N1 influenza (pH1N1) virus caused the first influenza pandemic in 40 y. The virus was identified as a triple reassortant between avian, swine, and human influenza viruses, highlighting the importance of reassortment in the generation of viruses with pandemic potential. Previously, we showed that a reassortant virus composed of wild-type avian H9N2 surface genes in a seasonal ...