In their review of live attenuated influenza vaccine (LAIV), Esposito et al. stated that in the US and Europe, LAIV is not recommended for children and adults with asthma and children younger than 5 years of age with a history of recurrent wheezing. While this statement is accurate for the US, it is not accurate for the European Union. The European Medicines Agency approved LAIV for use in chil...

Background and Aims: Wild-type RS-12 strain of mumps virus has been isolated from an Iranian patient and has been attenuated after several serial passages. This study was designed to determine nucleotide and amino acid substitutions in the HN, F and SH genes during attenuation of the wild-type virus. Materials and Methods: Required viral samples prepared at Razi Vaccine and Serum Institute. Vi...

Development of live attenuated influenza vaccines (LAIV) against avian strains with pandemic potential is an important public-health strategy. Either 1 or 2 10(7)-TCID(50) doses of H9N2 LAIV A/chicken/Hong Kong/G9/97 were administered intranasally to 50 adults in isolation; 41 participants were H9N2 seronegative, 24 of whom received 2 doses. The vaccine was well tolerated; vaccine shedding was ...

BACKGROUND The A(H1N1)pdm09 virus strain used in the live attenuated influenza vaccine was changed for the 2015-2016 influenza season because of its lack of effectiveness in young children in 2013-2014. The Influenza Vaccine Effectiveness Network evaluated the effect of this change as part of its estimates of influenza vaccine effectiveness in 2015-2016. METHODS We enrolled patients 6 months ...

Development and improvement of quality control tests for live attenuated vaccines are a high priority because of safety concerns. Live attenuated influenza vaccine (LAIV) viruses are 6:2 reassortants containing the hemagglutinin (HA) and neuraminidase (NA) gene segments from circulating influenza viruses to induce protective immune responses, and the six internal gene segments from a cold-adapt...

To develop attenuated bacteria as potential live vaccines, sparfloxacin was used in this study to modify 40 isolates of Streptococcus agalactiae. Majority of S. agalactiae used in this study were able to develop at least 80-fold resistance to sparfloxacin. When the virulence of the sparfloxacin-resistant S. agalactiae isolates were tested in 10-12g Nile tilapia by intraperitoneal injection at d...

The robust immune response to a single dose of pandemic 2009 H1N1 vaccine suggests that a large segment of the population has been previously primed. We evaluated the effect of seasonal (s) H1N1 infection, s-trivalent inactivated vaccine (s-TIV), and trivalent s-live attenuated influenza vaccine (s-LAIV) before immunization with a pandemic live attenuated influenza vaccine (p-LAIV) in mice. We ...

Owing to the variability of influenza viruses, vaccine composition needs to be up-dated annually. As many variables can influence their efficacy, vaccines are still considered "sub-optimal". Many studies have been carried out in recent years to improve vaccines. In particular, researchers and vaccine-producing corporations have focused on developing a live vaccine. Among the candidate vaccines,...

The vaccine against yellow fever is one of the safest and most effective ever developed. With an outstanding record in humans, has this live attenuated vaccine been overlooked as a promising vector for the development of vaccines against pathogens outside its own genus? Recent studies, including a report by Tao et al. on page 201 of this issue, have sparked renewed interest.