title: A cohort study of the impact and acquisition of naspharyngeal carriage of Streptococcus pneumoniae during the Hajj.
abstract: BACKGROUND
  The annual Muslim pilgrimage attracts over two million pilgrims who gather in a limited time and space. The pilgrimage carries the potential risk of increase risk of the acquisition of Streptococcus pneumonia. In this cohort study, we evaluate the effect of the Hajj on the prevalence of pneumococcal serotype nasopharyngeal carriage in the Hajj pilgrim population. The secondary objective is to evaluate the effects of the mass gathering on carriage of invasive pneumococcal serotypes.
  
  
  METHODS
  This is a prospective cohort study with two data collection periods: at the beginning and at the end of the Hajj. Nasopharyngeal samples were taken via a standardized swabbing method.
  
  
  RESULTS
  A total of 1175 pilgrims were enrolled at the beginning of the study and 1155 (98.3%) were included at the second part of the study. The pre-Hajj samples were obtained at a mean of 0 days and the post-Hajj sampling occurred at a mean of 15 days after arrival to Saudi Arabia. The overall carriage rate of Streptococcus pneumoniae in the pre- and post-Hajj was 1.8% and 7.1% (P = 0.0016). The potential coverage of the 7-valent pneumococcal conjugate vaccine (PCV7), PCV10 and PCV13 were 15.5%, 19.1%; and 35.5%, respectively. The coverage for the 23-valent pneumococcal polysaccharide vaccine (PPV23) was 40%.
  
  
  CONCLUSIONS
  Although there was an increase in the acquisition of S. pneumoniae, its magnitude is low which does not support public health recommendations for general pneumococcal vaccination of pilgrims except those at risk.
authors.affiliation: Ministry of Health, Riyadh, Saudi Arabia; Alfaisal University, College of Medicine, Riyadh, Saudi Arabia. Electronic address: Zmemish@yahoo.com.
authors.forename: Ziad A
authors.initials: ZA
authors.lastname: Memish
authors.affiliation: Johns Hopkins Aramco Healthcare, Dharan, Saudi Arabia; Indiana University School of Medicine, Indianapolis, IN, USA.
authors.forename: Jaffar A
authors.initials: JA
authors.lastname: Al-Tawfiq
authors.affiliation: Ministry of Health, Riyadh, Saudi Arabia.
authors.forename: Malak
authors.initials: M
authors.lastname: Almasri
authors.affiliation: Ministry of Health, Riyadh, Saudi Arabia.
authors.forename: Nadia
authors.initials: N
authors.lastname: Akkad
authors.affiliation: Ministry of Health, Riyadh, Saudi Arabia.
authors.forename: Saber
authors.initials: S
authors.lastname: Yezli
authors.affiliation: Makkah Regional Health Directorate, Makkah, Ministry of Health, Riyadh, Saudi Arabia.
authors.forename: Abdulhafeez
authors.initials: A
authors.lastname: Turkestani
authors.affiliation: German National Reference Center for Streptococci, Aachen, Germany.
authors.forename: Mark
authors.initials: M
authors.lastname: van der Linden
authors.affiliation: Ministry of Health, Riyadh, Saudi Arabia.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Assiri
mesh_terms: D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D002675:Child, Preschool; D015331:Cohort Studies; D003441:Crowding; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine / Q000008:administration & dosage; D006801:Humans; D007223:Infant; D007514:Islam; D008297:Male; D008399:Mass Behavior; D009305:Nasopharynx / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000008:administration & dosage; D015995:Prevalence; D011446:Prospective Studies; D012529:Saudi Arabia / Q000453:epidemiology; D065288:Serogroup; D013296:Streptococcus pneumoniae / Q000302:isolation & purification*; D014195:Travel; D014611:Vaccination; D018074:Vaccines, Conjugate / Q000008:administration & dosage
chemical_list: C586648:10-valent pneumococcal conjugate vaccine; C538862:13-valent pneumococcal vaccine; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate
keywords: Hajj; Mass gathering; Pneumococcus; Streptococcus pneumoniae