1). The oral fluid assay, using a modified TRFIA to detect specific VZV-IgG antibody, was chosen because it avoids any invasive procedure to collect blood and is more likely to be acceptable to parents and adolescents, thus improving study response rates. A recently proposed change to the UK adolescent vaccination programme would
mean that a group C meningococcal booster vaccine may be offered with the Td/IPV (tetanus, diphtheria, polio) booster to those aged 13–14 , and an adolescent varicella vaccination programme could be given at the same time. The average age of participants in this study was 13 years, and the study population intentionally reflects ethnic diversity in the UK adolescent general population through the inclusion of two schools in South London to increase the number of non-white respondents. Among all study respondents providing an oral fluid sample, 82% tested positive for VZV-IgG, which reflects the likely prevalence in the UK for this age group. www.selleckchem.com/products/fg-4592.html  Our study, however, did not aim to provide population prevalence estimates for the different chickenpox history responses because it was not possible to assess how accurately respondents reflect the population. For example, parents of adolescents with negative or uncertain histories may have been more likely to participate given the
provision of free vaccine to those without VZV-IgG antibodies. The proportion with different histories may also have been affected by changing the question about chickenpox selleckchem history at the end of the study to boost the number of negative and uncertain responses, and the small token of appreciation offered. Finally, it is difficult to foresee how parents’ answers might be influenced by the prospect of their child actually receiving a vaccine in the context of a national adolescent vaccination programme. We show that asking parents to report their child’s chickenpox
history can significantly discriminate between adolescents who are immune and susceptible to varicella infection. These data will be used to determine by modelling whether reported history, with or without oral fluid testing in those with negative or uncertain history, is sufficiently discriminatory found to underpin a cost-effective varicella vaccination programme that will protect susceptibles against chickenpox in the UK. Ethical approval was granted by the London Harrow National Research Ethics Service (11/LO/1916). The field and laboratory work for this study were supported by a grant from the DH Research and Development Directorate, grant number 039/0031. The views expressed in the publication are those of the authors and not necessarily those of the Department of Health, England. Nigel Field is supported by a NIHR Academic Clinical Lectureship. The funding sources had no role in data collection, data analysis, data interpretation or writing of the report. The study was designed and implemented by NF, GA, PW, NA, AJvH, KEB and EM, with EM as the Chief Investigator.