title: Estimating seroprevalence of vaccine-preventable infections: is it worth standardizing the serological outcomes to adjust for different assays and laboratories?
abstract: The aim of the European Sero-Epidemiology Network 2 (ESEN2) project was to estimate age-specific seroprevalence for a number of vaccine-preventable diseases in Europe. To achieve this serosurveys were collected by 22 national laboratories. To adjust for a variety of laboratory methods and assays, all quantitative results were transformed to a reference laboratory's units and were then classified as positive or negative to obtain age-specific seroprevalence. The aim of this study was to assess the value of standardization by comparing the crude and standardized seroprevalence estimates. Seroprevalence was estimated for measles, mumps, rubella, diphtheria, varicella zoster and hepatitis A virus (HAV) and compared before and after serological results had been standardized. The results showed that if no such adjustment had taken place, seroprevalence would have differed by an average of 3·2% (95% bootstrap interval 2·9-3·6) although this percentage varied substantially by antigen. These differences were as high as 16% for some serosurveys (HAV) which means that standardization could have a considerable impact on seroprevalence estimates and should be considered when comparing serosurveys performed in different laboratories using different assay methods.
authors.affiliation: Public Health England,London,UK.
authors.forename: G
authors.initials: G
authors.lastname: Kafatos
authors.affiliation: Public Health England,London,UK.
authors.forename: N
authors.initials: N
authors.lastname: Andrews
authors.affiliation: Department of Mathematics and Statistics,The Open University,Milton Keynes,UK.
authors.forename: K J
authors.initials: KJ
authors.lastname: McConway
authors.affiliation: National Retrovirus Reference Centre,Department of Hygiene and Epidemiology,University of Athens Medical School,Athens,Greece.
authors.forename: C
authors.initials: C
authors.lastname: Anastassopoulou
authors.affiliation: St Luke's Hospital,G'Mangia,Malta.
authors.forename: C
authors.initials: C
authors.lastname: Barbara
authors.affiliation: Centro Nacional de Microbiologia,Instituto de Salud Carlos III,Majadahonda,Madrid,Spain.
authors.forename: F
authors.initials: F
authors.lastname: De Ory
authors.affiliation: Swedish Institute for Infectious Disease Control,Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Johansen
authors.affiliation: Laboratoire National de Santé,Luxembourg.
authors.forename: J
authors.initials: J
authors.lastname: Mossong
authors.affiliation: Laboratory for Public Health Virology,Ljubljana,Slovenia.
authors.forename: K
authors.initials: K
authors.lastname: Prosenc
authors.affiliation: Scientific Institute of Public Health,Brussels,Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Vranckx
authors.affiliation: Public Health England,London,UK.
authors.forename: A
authors.initials: A
authors.lastname: Nardone
authors.affiliation: Public Health England,London,UK.
authors.forename: R
authors.initials: R
authors.lastname: Pebody
authors.affiliation: Department of Mathematics and Statistics,The Open University,Milton Keynes,UK.
authors.forename: P
authors.initials: P
authors.lastname: Farrington
mesh_terms: D000293:Adolescent; D000328:Adult; D002644:Chickenpox / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control; D002648:Child; D002675:Child, Preschool; D004165:Diphtheria / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control; D004168:Diphtheria Toxoid / Q000276:immunology / Q000627:therapeutic use*; D005060:Europe / Q000453:epidemiology; D006506:Hepatitis A / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control; D006801:Humans; D007223:Infant; D008457:Measles / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control; D009107:Mumps / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control; D012015:Reference Standards; D012409:Rubella / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control; D016036:Seroepidemiologic Studies; D014765:Viral Vaccines / Q000276:immunology / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D004168:Diphtheria Toxoid; D014765:Viral Vaccines
keywords: ESEN2; seroprevalence; serosurvey; standardization; vaccination