title: Seroprevalence of pertussis among adults in China where whole cell vaccines have been used for 50 years.
abstract: To estimate the true incidence of pertussis in Chinese adults who are at a childbearing age.
  
  
  
  A total of 897 serum samples from healthy individuals aged 20-39 years were selected randomly from a large number of serum samples collected in 2010 in Beijing, China. Anti-pertussis toxin (Ptx) IgG antibodies were determined with the Virion/Serion ELISA kits using purified Ptx as a coating antigen.
  
  
  
  Only 124 (13.8%) were found to have undetectable anti-Ptx IgG antibodies. The mean concentration was 13.76 IU/ml (95% CI, 12.37-15.15). Forty-six (5.1%) subjects had anti-Ptx IgG levels greater than or equal to 40 IU/ml, indicative of a pertussis infection, and nine (1%) had IgG antibodies greater than or equal to 100 IU/ml, indicative of a recent infection within a year. No significant differences were observed between age groups of 20-29 and 30-39 years, or between genders.
  
  
  
  Our study showed that about 5% of adults aged 20-39 years had positive anti-Ptx IgG antibodies, suggesting that adult pertussis is common in China. Giving a booster vaccination to pregnant women should possibly be considered in order to protect young infants who are too young to be vaccinated in this country.
authors.affiliation: Department of Medical Microbiology, Capital Medical University, Beijing, China.
authors.forename: Zhiyun
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Beijing Youan Hospital, Capital Medical University, Beijing, China; Collaborative Innovation Center of Infectious Diseases, Capital Medical University, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Medical Microbiology, Capital Medical University, Beijing, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Cao
authors.affiliation: Department of Medical Microbiology, Capital Medical University, Beijing, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Department of Medical Microbiology, Capital Medical University, Beijing, China.
authors.forename: Junping
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Department of Medical Microbiology, Capital Medical University, Beijing, China.
authors.forename: Guoling
authors.initials: G
authors.lastname: Ping
authors.affiliation: Centre for Disease Control and Prevention, Chaoyang District, Beijing, China.
authors.forename: Jianhong
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Centre for Disease Control and Prevention, Chaoyang District, Beijing, China. Electronic address: kszz_001@126.com.
authors.forename: Shuming
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Medical Microbiology, Capital Medical University, Beijing, China; Department of Medical Microbiology and Immunology, University of Turku, Turku, Finland. Electronic address: Qiushui.He@utu.fi.
authors.forename: Qiushui
authors.initials: Q
authors.lastname: He
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D037342:Pertussis Toxin / Q000276:immunology*; D010567:Pertussis Vaccine / Q000008:administration & dosage*; D016036:Seroepidemiologic Studies; D022282:Vaccines, Acellular / Q000008:administration & dosage; D014917:Whooping Cough / Q000453:epidemiology* / Q000517:prevention & control; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D010567:Pertussis Vaccine; D022282:Vaccines, Acellular; D037342:Pertussis Toxin
keywords: ELISA; Immunization; Pertussis; Pertussis toxin IgG; Seroprevalence