Surveillance of Australian Hajj pilgrims for carriage of potentially pathogenic bacteria: Data from two pilot studies

Abstract

AIMTo estimate the pharyngeal carriage rate of Neisseria meningitidis (N. meningitidis), Streptococcus pneumoniae (S. pneumoniae) and Staphylococcus aureus (S. aureus) among Australian Hajj pilgrims.METHODSIn 2014, surveillance was conducted in two phases among Australian Hajj pilgrims: The first phase during Hajj in Mina, and the second phase soon after returning home to Australia. Nasopharyngeal or oropharyngeal swabs were taken from participants then tested, firstly by nucleic acid testing, and also by standard culture.RESULTSOf 183 participants recruited in the first phase, 26 (14.2%) tested positive for S. pneumoniae; 4 had received pneumococcal conjugate vaccine (PCV13). Only one tested positive for N. meningitidis (W). Of 93 2nd phase samples cultured, 17 (18.3%) grew S. aureus, all methicillin sensitive, 2 (2.2%) grew N. meningitidis (on subculture; one serotype B, one negative), and 1 (1%), from an unvaccinated pilgrim, grew S. pneumoniae.CONCLUSIONRelatively high carriage of S. pneumoniae and little meningococcal carriage was found. This indicates the importance of a larger study for improved infection surveillance and possible vaccine evaluation.

Impact of the Hajj on pneumococcal carriage and the effect of various pneumococcal vaccines

“…The year after, during the 2013 Hajj, 56.1% of the PPV23-vaccinated French pilgrims were positive for S. pneumoniae at the end of the Hajj, compared to 68.3% in the control group [19]. In the Australian cohort, the carriage of S. pneumoniae was 10.5% in PCV13-vaccinated pilgrims versus 15.2% in unvaccinated pilgrims during the Hajj 2014, a difference which was not significant; post-Hajj S. pneumoniae carriage was nil in the vaccinated group and 1.8% in controls17] [24]. However, Ismail et al are the only to report a significant reduction of S. pneumoniae acquisition in vaccinated Malaysian pilgrims (5/388, 1.3%) compared to unvaccinated pilgrims [(5/100, 5%), (p = 0.03)] [23].…”

“…A 1.81% pharyngeal carriage of S. pneumoniae was described in 551 Malaysian pilgrim returning from Hajj 2013 using culture; pre-Hajj data were not collected [23]. In 2014, pneumococcal carriage was evaluated to 14.2% using qPCR in pilgrims from Australia at the fifth days of the pilgrimage and decrease to 1.1% in pilgrims sampled two months after the pilgrimage [24]. However, only 30/246 pilgrims were paired in the 2 phases of their study and the diagnostic test used for the samples collected during and after the Hajj differed.…”

Meningococcal carriage in high-risk settings: A systematic review

“…Three studies among Hajj pilgrims met the inclusion criteria (Azeem et al, 2017;Ceyhan et al, 2013;Memish et al, 2017), and no eligible studies were conducted among Umrah pilgrims. Each of the included studies investigated serogroup-specific carriage among pilgrims both before and after the Hajj.…”

“…Study variables affecting carriage prevalence also varied. Nearly all pilgrims from two studies were vaccinated with the quadrivalent (ACWY) polysaccharide vaccine prior to the pilgrimage (Ceyhan et al, 2013;Memish et al, 2017), while one study reported approximately one-third of the pilgrims were vaccinated with the quadrivalent conjugate vaccine (Azeem et al, 2017). Chemoprophylaxis was given to pilgrims from countries of the African meningitis belt upon arrival at the airport in Saudi Arabia.…”

“…Laboratory methods also varied between studies (Supplementary material, Table S4). The site of swabbing was inconsistent between studies, with one using nasopharyngeal swabs (Memish et al, 2017), one posterior pharyngeal swabs (Azeem et al, 2017), and one both oropharyngeal and nasopharyngeal swabs (Ceyhan et al, 2013). Only one study swabbed participants both prior to and after vaccine administration (Ceyhan et al, 2013), while the other two swabbed participants only after administration (Azeem et al, 2017;Memish et al, 2017).…”