tetano
Editor, Senior Moderator
Pediatr Infect Dis J. 2013 Sep 20. [Epub ahead of print]
Characteristics of Vaccine Failures in a Randomized Placebo-Controlled Trial of Inactivated Influenza Vaccine in Children.
Ng S, Ni MY, Fang VJ, Ip DK, Chan KH, Leung GM, Peiris JS, Cowling BJ.
Source
1.School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China. 2.Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA. 3.Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China. 4.Centre for Influenza Research, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.
Abstract
BACKGROUND::
Infections occurring among vaccinated persons (vaccine failures) are known to occur in vaccines with imperfect efficacy. Failures among vaccinated children who were infected with vaccine-matched influenza B virus strain have not been adequately characterized.
METHODS::
Taking advantage of a randomized controlled trial (RCT) of trivalent seasonal influenza vaccine (TIV), the viral shedding and clinical symptoms associated with RT-PCR confirmed influenza B infection, and serum haemaggluttination inhibiting antibody response to vaccine were compared between children 6-17y receiving TIV and placebo.
RESULTS::
Vaccine failures were observed to show lower antibody response to TIV compared to other vaccine recipients. We did not find any evidence that vaccination reduced the severity or duration of clinical symptoms of RT-PCR confirmed vaccine-matched influenza B infections. Vaccination was not observed to alter viral load or shedding duration.
CONCLUSION::
TIV was not observed to ameliorate clinical symptoms or viral shedding among vaccine failures compared with infected placebo recipients. Lower antibody response might have explained vaccine failure and also lack of effect in reducing clinical symptoms and viral shedding upon infection. Our results are based on a RCT of split virus inactivated vaccine and may not be applicable to other vaccine types. Further studies in vaccine failure among children will be important in future vaccine development.
PMID:
24061274
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/24061274
Characteristics of Vaccine Failures in a Randomized Placebo-Controlled Trial of Inactivated Influenza Vaccine in Children.
Ng S, Ni MY, Fang VJ, Ip DK, Chan KH, Leung GM, Peiris JS, Cowling BJ.
Source
1.School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China. 2.Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA. 3.Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China. 4.Centre for Influenza Research, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.
Abstract
BACKGROUND::
Infections occurring among vaccinated persons (vaccine failures) are known to occur in vaccines with imperfect efficacy. Failures among vaccinated children who were infected with vaccine-matched influenza B virus strain have not been adequately characterized.
METHODS::
Taking advantage of a randomized controlled trial (RCT) of trivalent seasonal influenza vaccine (TIV), the viral shedding and clinical symptoms associated with RT-PCR confirmed influenza B infection, and serum haemaggluttination inhibiting antibody response to vaccine were compared between children 6-17y receiving TIV and placebo.
RESULTS::
Vaccine failures were observed to show lower antibody response to TIV compared to other vaccine recipients. We did not find any evidence that vaccination reduced the severity or duration of clinical symptoms of RT-PCR confirmed vaccine-matched influenza B infections. Vaccination was not observed to alter viral load or shedding duration.
CONCLUSION::
TIV was not observed to ameliorate clinical symptoms or viral shedding among vaccine failures compared with infected placebo recipients. Lower antibody response might have explained vaccine failure and also lack of effect in reducing clinical symptoms and viral shedding upon infection. Our results are based on a RCT of split virus inactivated vaccine and may not be applicable to other vaccine types. Further studies in vaccine failure among children will be important in future vaccine development.
PMID:
24061274
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/24061274