A potential association between obesity and reduced effectiveness of COVID-19 vaccine-induced neutralizing humoral immunity.

Due to the adverse effects of obesity on host immunity, this study investigated the effectiveness of COVID-19 vaccines (BNT162b2, ChAdOx-nCov-2019, and mRNA-1273) in inducing anti-SARS-CoV-2 Spike (S) neutralizing antibodies among individuals with various obesity classes (class I, II, III, and super obesity). Sera from vaccinated obese individuals (n = 73) and normal BMI controls (n = 46) were subjected to S-based enzyme-linked immunosorbent assay (ELISA) and serum-neutralization test (SNT) to determine the prevalence and titer of anti-SARS-CoV-2 neutralizing antibodies. Nucleocapsid-ELISA was also utilized to distinguish between immunity acquired via vaccination only versus vaccination plus recovery from infection. Data were linked to participant demographics including age, gender, past COVID-19 diagnosis, and COVID-19 vaccination profile. S-based ELISA demonstrated high seroprevalence rates (>97%) in the study and control groups whether samples with evidence of past infection were included or excluded. Interestingly, however, SNT demonstrated a slightly significant reduction in both the rate and titer of anti-SARS-CoV-2 neutralizing antibodies among vaccinated obese individuals (60/73; 82.19%) compared to controls (45/46; 97.83%). The observed reduction in COVID-19 vaccine-induced neutralizing humoral immunity among obese individuals occurs independently of gender, recovery from past infection, and period from last vaccination. Our data suggest that COVID-19 vaccines are highly effective in inducing protective humoral immunity. This effectiveness, however, is potentially reduced among obese individuals which highlight the importance of booster doses to improve their neutralizing immunity. Further investigations on larger sample size remain necessary to comprehensively conclude about the effect of obesity on COVID-19 vaccine effectiveness on humoral immunity induction.

Syndromic surveillance of respiratory-tract infections and hand hygiene practice among pilgrims attended Hajj in 2021: a cohort study.

BACKGROUND: The risk of transmission of viral respiratory tract infections (RTIs) is high in mass gatherings including Hajj. This cohort study estimated the incidence of symptomatic RTIs and hand hygiene compliance with its impact among Hajj pilgrims during the COVID-19 pandemic. METHODS: During the week of Hajj rituals in 2021, domestic pilgrims were recruited by phone and asked to complete a baseline questionnaire. Pilgrims were followed up after seven days using a questionnaire about the development of symptoms, and practices of hand hygiene. Syndromic definitions were used to clinically diagnose 'possible' influenza-like illnesses (ILI) and COVID-19 infection. RESULTS: A total of 510 pilgrims aged between 18 and 69 (median of 50) years completed the questionnaire, 280 (54.9%) of whom were female, and all of them (except for one) were vaccinated against COVID-19 with at least one dose. The mean (± SD) of pilgrims' hand hygiene knowledge score (on a scale of 0 to 6) was 4.15 (± 1.22), and a higher level of knowledge was correlated with a higher frequency of handwashing using soap and water. Among those 445 pilgrims who completed the follow-up form, 21 (4.7%) developed one or more respiratory symptoms, of which sore throat and cough were the commonest (respectively 76.2% and 42.8%); 'possible ILI' and 'possible COVID-19' were present in 1.1% and 0.9% of pilgrims. Obesity was found to be a significant factor associated with the risk of developing RTIs (odds ratio = 4.45, 95% confidence interval 1.15-17.13). CONCLUSIONS: Hajj pilgrims are still at risk of respiratory infections. Further larger and controlled investigations are needed to assess the efficacy of hand hygiene during Hajj.

Multiple Sources of Genetic Diversity of Influenza A Viruses during the Hajj.

Outbreaks of respiratory virus infection at mass gatherings pose significant health risks to attendees, host communities, and ultimately the global population if they help facilitate viral emergence. However, little is known about the genetic diversity, evolution, and patterns of viral transmission during mass gatherings, particularly how much diversity is generated by in situ transmission compared to that imported from other locations. Here, we describe the genome-scale evolution of influenza A viruses sampled from the Hajj pilgrimages at Makkah during 2013 to 2015. Phylogenetic analysis revealed that the diversity of influenza viruses at the Hajj pilgrimages was shaped by multiple introduction events, comprising multiple cocirculating lineages in each year, including those that have circulated in the Middle East and those whose origins likely lie on different continents. At the scale of individual hosts, the majority of minor variants resulted from de novo mutation, with only limited evidence of minor variant transmission or minor variants circulating at subconsensus level despite the likely identification of multiple transmission clusters. Together, these data highlight the complexity of influenza virus infection at the Hajj pilgrimages, reflecting a mix of global genetic diversity drawn from multiple sources combined with local transmission, and reemphasize the need for vigilant surveillance at mass gatherings.IMPORTANCE Large population sizes and densities at mass gatherings such as the Hajj (Makkah, Saudi Arabia) can contribute to outbreaks of respiratory virus infection by providing local hot spots for transmission followed by spread to other localities. Using a genome-scale analysis, we show that the genetic diversity of influenza A viruses at the Hajj gatherings during 2013 to 2015 was largely shaped by the introduction of multiple viruses from diverse geographic regions, including the Middle East, with only little evidence of interhost virus transmission at the Hajj and seemingly limited spread of subconsensus mutational variants. The diversity of viruses at the Hajj pilgrimages highlights the potential for lineage cocirculation during mass gatherings, in turn fuelling segment reassortment and the emergence of novel variants, such that the continued surveillance of respiratory pathogens at mass gatherings should be a public health priority.

The relationship between hand hygiene and rates of acute respiratory infections among Umrah pilgrims: A pilot randomised controlled trial.

BACKGROUND: There is a lack of randomised controlled trials (RCTs) investigating the role of hand hygiene in preventing and containing acute respiratory infections (ARIs) in mass gatherings. In this pilot RCT, we assessed the feasibility of establishing a large-scale trial to explore the relationship between practising hand hygiene and rates of ARI in Umrah pilgrimage amidst the COVID-19 pandemic. METHODS: A parallel RCT was conducted in hotels in Makkah, Saudi Arabia, between April and July 2021. Domestic adult pilgrims who consented to participate were randomised 1:1 to the intervention group who received alcohol-based hand rub (ABHR) and instructions, or to the control group who did not receive ABHR or instructions but were free to use their own supplies. Pilgrims in both groups were then followed up for seven days for ARI symptoms. The primary outcome was the difference in the proportions of syndromic ARIs among pilgrims between the randomised groups. RESULTS: A total of 507 (control: intervention = 267: 240) participants aged between 18 and 75 (median 34) years were randomised; 61 participants were lost to follow-up or withdrew leaving 446 participants (control: intervention = 237:209) for the primary outcome analysis; of whom 10 (2.2 %) had developed at least one respiratory symptom, three (0.7 %) had 'possible ILI' and two (0.4 %) had 'possible COVID-19'. The analysis of the primary outcome found no evidence of difference in the proportions of ARIs between the randomised groups (odds ratio 1.1 [0.3-4.0] for intervention relative to control). CONCLUSION: This pilot trial suggests that conducting a future definitive RCT to assess the role of hand hygiene in the prevention of ARIs is feasible in Umrah setting amidst such a pandemic; however, outcomes from this trial are inconclusive, and such a study would need to be very large given the low rates of outcomes observed here. TRIAL REGISTRATION: This trial was registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) (ACTRN12622001287729), the full protocol can be accessed there.

Saudi Cerebral Palsy Register (SCPR): Protocol on the Methods and Technical Details.

This protocol presents a comprehensive proposal for the establishment of the Saudi Cerebral Palsy Register (SCPR), a crucial project for investigating and addressing the prevalence, etiology, and management of cerebral palsy (CP) in Saudi Arabia. The SCPR will not only provide a robust database for ongoing research and analysis but will also serve as a platform for investigating the causes of CP, implementing preventative strategies, and improving the quality of care and outcomes for people with CP and their families in Saudi Arabia. Detailed case definitions, inclusion/exclusion criteria, and data collection protocols are discussed to ensure the integrity and comparability of the data. The plan also outlines strategic funding, institutional and government endorsement, sustainability considerations, potential challenges and proposed solutions, and expected outcomes and impact. These include creating research and educational opportunities, fostering regional and international collaborations, and significantly contributing to CP prevention strategies. Overcoming anticipated obstacles, such as stigma, institutional policies, and collaborations, and securing both necessary funding and endorsements are highlighted as critical for the success of the SCPR. The project is not only aligned with promote prevention of health risks, a target of Vision 2030 in Saudi Arabia, but is also expected to have a substantial impact on the health and quality of life of people with CP and their families in Saudi Arabia, serving as inspiration for similar efforts worldwide.

Meningococcal B Immunisation in Adults and Potential Broader Immunisation Strategies: A Narrative Review.

Recombinant vaccines against invasive meningococcal disease due to Neisseria meningitidis serogroup B (MenB) have shown substantial impact in reducing MenB disease in targeted populations. 4CMenB targets four key N. meningitidis protein antigens; human factor H binding protein (fHbp), Neisserial heparin binding antigen (NHBA), Neisseria adhesin A (NadA) and the porin A protein (PorA P1.4), with one or more of these expressed by most pathogenic MenB strains, while MenB-FHbp targets two distinct fHbp variants. While many countries recommend MenB immunisation in adults considered at high risk due to underlying medical conditions or immunosuppression, there are no recommendations for routine use in the general adult population. We reviewed the burden of MenB in adults, where, while incidence rates remain low (and far lower than in young children < 5 years of age at greatest risk), a substantial proportion of MenB cases (20% or more) is now observed in the adult population; evident in Europe, Australia, and in the United States. We also reviewed immunogenicity data in adults from clinical studies conducted during MenB vaccine development and subsequent post-licensure studies. A 2-dose schedule of 4CMenB generates hSBA titres ≥ 1:4 towards all four key vaccine target antigens in up to 98-100% of subjects. For MenB-FHbp, a ≥ fourfold rise in hSBA titres against the four primary representative test strains was observed in 70-95% of recipients following a 3-dose schedule. While this suggests potential benefits for MenB immunisation if used in adult populations, data are limited (especially for adults > 50 years) and key aspects relating to duration of protection remain unclear. Although a broader adult MenB immunisation policy could provide greater protection of the adult population, additional data are required to support policy decision-making.

Evaluation of the Most Visible Symptoms Associated with COVID-19 Vaccines Among the Residents of Makkah, Saudi Arabia: An Observational, Cross-Sectional Study.

Background: This research evaluated the most visible symptoms associated with coronavirus (COVID-19) vaccines among residents in Makkah of Saudi Arabia. Methods: A cross-sectional study was conducted in 2021 among a representative sample of residents receiving COVID-19 vaccination at King Abdullah Medical City, Al Ukayshiyyah, and Umm Al-Qura University vaccination centers. A total of 805 participants selected by a census sampling method were included. Data regarding characteristics, medical history, and post-vaccination symptoms were obtained with an interview-based questionnaire. Results: The participants' mean age was 25.20 ± 15.5 years. Of them, 61.7% and 38.3% received one and two doses of the COVID-19 vaccine, respectively. 2.2% have an allergic reaction to the COVID-19 vaccine. 25.3% were infected with COVID-19, 23% were infected before the first dose, and only 1.6% were infected after the first dose. Significant statistical associations were found between males and females in smoking status, age, body mass index, history of diabetes mellitus, and types of COVID-19 vaccines (P-value < 0.05). After adjustment for confounding variables, male participants had lower odds of having swelling, redness, or pain at the injection site, muscle or joint pain, headache, dizziness, and nausea compared to female participants [OR = 0.596, 95% CI = (0.388-0.916)], [OR = 0.272, 95% CI = (0.149-0.495)], [OR = 0.529, 95% CI = (0.338-0.828)], [OR = 0.263, 95% CI = (0.125-0.554)], and [OR = 0.145, 95% CI = (0.31-0.679), P < 0.05 for all], respectively. Conclusion: The female participants may have a higher risk of post-COVID-19 vaccination symptoms than males among Makkah residents of Saudi Arabia.

Evaluation of the rate, pattern and appropriateness of antibiotic prescription in a cohort of pilgrims suffering from upper respiratory tract infection during the 2018 Hajj season.

Hajj is associated with an increased risk of the transmission of infectious diseases including upper respiratory tract infections (URTIs). It can be a focal point for the emergence, persistence and dissemination of antimicrobial-resistant (AMR) bacteria. The overuse of antibiotics during Hajj can promote the development of antimicrobial resistance. Little information is known regarding the true appropriateness of prescribing antibiotics for treating URTIs during Hajj. Here we studied the rate, patterns and appropriateness of antibiotic prescription among a cohort of pilgrims who were treated for URTIs during the 2018 Hajj season. Adult pilgrims who sought medical services for URTIs [presenting with coryza, runny nose, nasal irritation, nasal congestion, cough, sore throat, headache or fever (even if subjective)] within the Holy sites were enrolled in this study and consented to provide swabs and medical information. A total of 121 pilgrims were enrolled, with the majority (60.3 %) originating from North African Arab countries. Most were male (89.3 %) with a median age of 45 years. Bacterial infections were detected in 7.3 % (n=9) of the URTI cases. The identified bacteria included Haemophilus influenzae (n=6, all resistant to ampicillin), Streptococcus pneumoniae (n=2), Staphylococcus aureus (n=1, resistant to oxacillin) and Moraxella catarrhalis (n=1, resistant to ampicillin and trimethoprim/sulfamethoxazole). The antibiotic prescription rate was 52.1%, most of which was amoxicillin (81 %). The data demonstrated that the proportion of appropriate practices in treating bacterial URTIs in this cohort was 45.5 %. This study highlights the need for implementing laboratory identification of the aetiological agents and related AMR profiles when treating URTIs in Hajj, rather than relying on clinical assessment alone.

Acute Complications of Diabetes Among Pilgrims During Hajj 2017: A Brief Report.

INTRODUCTION: Diabetes mellitus (DM) was reported as one of the most common non-communicable diseases during Hajj. However, few studies evaluated acute complications of DM during Hajj. Therefore, this study aims to explore the most common acute complications among pilgrims with DM during Hajj 2017 and its clinical presentations. METHODS: This is a descriptive cross-sectional study. Data were collected using an anonymous questionnaire from the database of pilgrims with DM, who sought medical care in mobile clinics in Mina during the peak period of Hajj from 31 August to 4 September 2017. Data were entered afterwards into an Excel sheet and analyzed using SPSS. RESULTS: In this study, a total of 281 pilgrims were recruited, male to female ratio 3:1. Out of 281 pilgrims, 199 (70.8%) had foot injuries, 77 (27.4%) had hyperglycemia, and 37 (13.2%) had hypoglycemia, noting that some of them presented with more than one complication. Most of the participants who developed foot injuries, presented with redness (28.8%) and bullous (20.6%). The most reported symptoms among hyperglycemic pilgrims were polydipsia (17.1%) and dry mouth (16.4%). Also, the most reported symptoms of hypoglycemia were fatigue (14.9%) and headache (12.5%). In addition, pilgrims with type 2 DM reported a higher rate of acute complications compared to type 1 DM (81.8% versus 18.2%, p = 0.33). CONCLUSION: The most common acute complication of diabetes during Hajj is foot injury. Pilgrims who suffered from hyperglycemia presented mainly with polydipsia, while those who developed hypoglycemia presented mainly with fatigue. There was no statistically significant difference according to the association between the type of diabetes and the occurrence of acute complications.

Pilot Survey of Knowledge, Attitudes and Perceptions of Hajj Deployed Health Care Workers on Antibiotics and Antibiotic Prescriptions for Upper Respiratory Tract Infections: Results from Two Hajj Seasons.

Antimicrobial resistance (AMR) is a global public health issue. Upper respiratory tract infections (URTIs) are common illnesses during Hajj, for which antibiotics are often inappropriately prescribed. Hajj healthcare workers' (HCW) knowledge, attitudes and perceptions (KAP) about AMR and antibiotic use for URTIs are not known. We conducted a survey among HCWs during Hajj to explore their KAP regarding antibiotic use for URTIs in pilgrims. Electronic or paper-based surveys were distributed to HCWs during the Hajj in 2016 and 2017. A total of 85 respondents aged 25 to 63 (median 40) years completed the surveys. Most participants were male (78.8%) and were physicians by profession (95.3%). Around 85% and 19% of respondents claimed to have heard about AMR and antimicrobial stewardship programs, respectively, among whom most had obtained their knowledge during their qualification. Implementation of URTI treatment guidelines was very low. In conclusion, HCWs at Hajj have significant knowledge gaps regarding AMR, often do not use standard clinical criteria to diagnose URTIs and display a tendency to prescribe antibiotics for URTIs.

Hand Hygiene Knowledge and Practices among Domestic Hajj Pilgrims: Implications for Future Mass Gatherings Amidst COVID-19.

This study examined Hajj pilgrims' knowledge and reported practice of hand hygiene. In Hajj 2019, a cross-sectional survey was undertaken in Mina, Makkah, Saudi Arabia, of domestic Saudi pilgrims aged ≥18 years by using a self-administered Arabic questionnaire that captured data on pilgrims' socio-demographics, hand hygiene knowledge, and reported practices of hand cleaning following certain actions. A total of 348 respondents aged 18 to 63 (median 32) years completed the survey, of whom 200 (57.5%) were female. The mean (±standard deviation (SD)) hand hygiene knowledge score was 6.7 (±SD 1.9). Two hundred and seventy one (77.9%) and 286 (82.2%) of respondents correctly identified that hand hygiene can prevent respiratory and gastrointestinal infections respectively, but 146 (42%) were not aware that it prevents hand-foot-mouth disease. Eighty-eight (25.3%) respondents erroneously reported that hand hygiene prevents HIV. Washing hands with water and soap was the most preferred method practiced before a meal (67.5% (235/348)), after a meal (80.2% (279/348)), after toilet action (81.6% (284/348)), when hands were visibly soiled (86.2% (300/348)), and after waste disposal (61.5% (214/348)). Hajj pilgrims demonstrated a good knowledge and practice of hand hygiene, but there are gaps that are vital to control outbreaks such as COVID-19.

Meningococcal and pneumococcal carriage in Hajj pilgrims: findings of a randomized controlled trial.

BACKGROUND: Intense congestion during the Hajj pilgrimage amplifies the risk of meningococcal carriage and disease, and there have been many meningococcal outbreaks reported amongst pilgrims. Thus, a strict vaccination policy is enforced by the host country and either polysaccharide or conjugate quadrivalent meningococcal vaccines are mandatory. However, unlike conjugate vaccines, the polysaccharide vaccine is not thought to reduce pharyngeal carriage of meningococci. METHODS: A single-blinded, randomized, controlled trial amongst pilgrims from Saudi Arabia and Australia during the Hajj seasons of 2016-2017 was conducted to compare MenACWY-Conjugate vaccine with MenACWY-Polysaccharide vaccine, to determine if the conjugate vaccine is more effective in reducing asymptomatic carriage of meningococci, and whether the effect may be long-standing. Oropharyngeal swabs were obtained pre-, immediately post- and 6-11 months following completion of Hajj and tested for the presence of meningococci. RESULTS: Amongst 2000 individuals approached, only 1146 participants aged 18-91 (mean 37.6) years agreed to participate and were randomized to receive either the polysaccharide (n = 561) or the conjugate (n = 561) vaccine, 60.8% were male, and 93.5% were from Saudi Arabia. Amongst oropharyngeal swabs obtained before Hajj, only two (0.2%) tested positive for Neisseria meningitidis. Similarly, meningococci were identified in only one sample at each of the post-Hajj and late follow-up visits. None of the carriage isolates were amongst the serogroups covered by the vaccines. A post hoc analysis of the third swabs revealed that 22.4% of all participants (50/223) were positive for Streptococcus pneumoniae nucleic acid. CONCLUSION: The low overall carriage rate of meningococci found amongst Hajj pilgrims in 2016 and 2017 demonstrates a successful vaccination policy, but neither supports nor refutes the superiority of meningococcal conjugate ACWY vaccine over the polysaccharide vaccine against carriage. Although an association could not be established in this study, molecular epidemiology would help to establish the role of Hajj in facilitating transmission of pneumococci and inform vaccination policy.

Facemask against viral respiratory infections among Hajj pilgrims: A challenging cluster-randomized trial.

BACKGROUND: In this large-scale cluster-randomized controlled trial (cRCT) we sought to assess the effectiveness of facemasks against viral respiratory infections. METHODS AND RESULTS: Over three consecutive Hajj seasons (2013, 2014, 2015) pilgrims' tents in Makkah were allocated to 'facemask' or 'no facemask' group. Fifty facemasks were offered to participants in intervention tents, to be worn over four days, and none were offered to participants in control tents. All participants recorded facemask use and respiratory symptoms in health diaries. Nasal swabs were collected from the symptomatic for virus detection by reverse transcription polymerase chain reaction. Clinical symptoms and laboratory results were analyzed by 'intention- to-treat' and 'per-protocol'. A total of 7687 adult participants from 318 tents were randomized: 3864 from 149 tents to the intervention group, and 3823 from 169 tents to the control group. Participants were aged 18 to 95 (median 34, mean 37) years, with a male to female ratio of 1:1.2. Overall, respiratory viruses were detected in 277 of 650 (43%) nasal/pharyngeal swabs collected from symptomatic pilgrims. Common viruses were rhinovirus (35.1%), influenza (4.5%) and parainfluenza (1.7%). In the intervention arm, respectively 954 (24.7%) and 1842 (47.7%) participants used facemasks daily and intermittently, while in the control arm, respectively 546 (14.3%) and 1334 (34.9%) used facemasks daily and intermittently. By intention-to-treat analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (odds ratio [OR], 1.4; 95% confidence interval [CI], 0.9 to 2.1, p = 0.18) nor against clinical respiratory infection (OR, 1.1; 95% CI, 0.9 to 1.4, p = 0.40). Similarly, in a per-protocol analysis, facemask use did not seem to be effective against laboratory-confirmed viral respiratory infections (OR 1.2, 95% CI 0.9-1.7, p = 0.26) nor against clinical respiratory infection (OR 1.3, 95% CI 1.0-1.8, p = 0.06). CONCLUSION: This trial was unable to provide conclusive evidence on facemask efficacy against viral respiratory infections most likely due to poor adherence to protocol.

Influenza vaccine effectiveness among Hajj pilgrims: a test-negative case-control analysis of data from different Hajj years.

Background: Influenza is a common respiratory infection at Hajj. Thus, influenza vaccine is recommended for Hajj pilgrims but data on its effectiveness from a large sample are unavailable. This analysis aims to assess the effectiveness of the trivalent seasonal influenza vaccine (TIV) among Hajj pilgrims.Patients and methods: A 'test-negative' case-control analysis using data from individual studies was conducted. Included studies involved participants from Saudi Arabia, India, Australia and the United Kingdom who attended Hajj in Makkah, Saudi Arabia in different years between 2005 and 2015. Pilgrims who developed symptoms of respiratory infection during Hajj were included in these studies. Participants' vaccination histories were recorded and respiratory samples were collected to test for influenza by PCR. Vaccine effectiveness (VE) was calculated after adjusting for potential confounders.Results: A total of 1,569 pilgrims were included in this analysis. Influenza vaccine uptake was 52.2% and the attack rate of influenza was 8.2%. The estimated overall VE was 43.4% (95% CI 11.4% to 63.9%, P = 0.01). VE against a specific subtype of influenza was not significant.Conclusion: The current analysis has shown that TIV is moderately effective among Hajj pilgrims, but the vaccine uptake has been suboptimal. Power was much reduced when testing for influenza subtypes.

Effect on meningococcal serogroup W immunogenicity when Tdap was administered prior, concurrent or subsequent to the quadrivalent (ACWY) meningococcal CRM197-conjugate vaccine in adult Hajj pilgrims: A randomised controlled trial.

Immune responses to the capsular polysaccharide administered in the polysaccharide-protein conjugate vaccines can be either improved or suppressed by the pre-existence of immunity to the carrier protein. Receiving multiple vaccinations is essential for travellers such as Hajj pilgrims, and the use of conjugated vaccines is recommended. We studied the immune response to meningococcal serogroup W upon prior, concurrent and sequential administration of a quadrivalent meningococcal conjugate vaccine (MCV4) conjugated to CRM197 (coadministered with 13 valent pneumococcal vaccine conjugate CRM197 [PCV13]), and tetanus-diphtheria-acellular pertussis (Tdap) vaccine in Australian adults before attending the Hajj pilgrimage in 2014. Participants were randomly assigned, by computer-generated numbers, to three study arms by 1:1:1 ratio. Group A received Tdap followed by MCV4-CRM197 (+PCV13) 3-4 weeks later. Group B received all three vaccines in a single visit. Group C received MCV4-CRM197 (+PCV13) followed by Tdap 3-4 weeks later. Blood samples obtained prior to and 3-4 weeks after immunisation with MCV4-CRM197 were tested for meningococcal serogroup W-specific serum bactericidal antibody responses using baby rabbit complement (rSBA). One hundred and seven participants aged between 18 and 64 (median 40) years completed the study. No significant difference in meningococcal serogroup W rSBA geometric mean titre (GMT) was observed between the study arms post vaccination with MCV-CRM197 but Group A tended to have a slightly lower GMT (A = 404, B = 984 and C = 1235, p = 0.15). No statistical difference was noticed between the groups in proportions of subjects achieving a ≥4-fold rise in rSBA titres or achieving rSBA titre ≥8 post vaccination. In conclusion, receipt of MCV4-CRM197 vaccine prior, concurrent or subsequent to Tdap has similar immunologic response, and hence concurrent administration is both immunogenic and practical. However, further investigation into whether carrier induced suppression is a public health issue is suggested. Clinical trial registration: ANZCTR no. ACTRN12613000536763.

Mandatory meningococcal vaccine, and other recommended immunisations: Uptake, barriers, and facilitators among health care workers and trainees at Hajj.

AIM: To evaluate the uptake of a mandatory meningococcal, a highly recommended influenza, and an optional pneumococcal vaccine, and to explore the key factors affecting vaccination rate among health care workers (HCWs) during the Hajj. METHODS: An anonymous cross-sectional online survey was distributed among HCWs and trainees who worked or volunteered at the Hajj 2015-2017 through their line managers, or by visiting their hospitals and healthcare centres in Makkah and Mina. Overseas HCWs who accompanied the pilgrims or those who work in foreign Hajj medical missions were excluded. Pearson's χ2 test was used to compare categorical variables and odds ratio (OR) was calculated by "risk estimate" statistics along with 95% confidence interval (95%CI). RESULTS: A total of 138 respondents aged 20 to 59 (median 25.6) years with a male to female ratio of 2.5:1 participated in the survey. Only 11.6% (16/138) participants reported receiving all three vaccines, 15.2% (21/138) did not receive any vaccine, 76.1% (105/138) received meningococcal, 68.1% (94/138) influenza and 13.8% (19/138) pneumococcal vaccine. Females were more likely to receive a vaccine than males (OR 3.6, 95%CI: 1.0-12.7, P < 0.05). Willingness to follow health authority's recommendation was the main reason for receipt of vaccine (78.8%) while believing that they were up-to-date with vaccination (39.8%) was the prime reason for non-receipt. CONCLUSION: Some HCWs at Hajj miss out the compulsory and highly recommended vaccines; lack of awareness is a key barrier and authority's advice is an important motivator. Health education followed by stringent measures may be required to improve their vaccination rate.

Influenza vaccination among Saudi Hajj pilgrims: Revealing the uptake and vaccination barriers.

BACKGROUND: Hajj is the world's largest annual mass gathering that attracts two to three million Muslims from around the globe to a religious assemblage in Makkah, Saudi Arabia. The risk of acquisition and transmission of influenza among Hajj pilgrims is high. Therefore, influenza vaccination is recommended, and was monitored frequently among pilgrims from different countries. However, the vaccination uptake among Saudi pilgrims has not been assessed in recent years. OBJECTIVE: This analysis aims to evaluate influenza vaccine uptake among Saudi Hajj pilgrims, and identify the key barriers to vaccination. METHOD: Data on influenza vaccination were obtained from Saudi pilgrims who took part in a large trial during the Hajj of 2013, 2014 and 2015. Pilgrims were met and recruited in Mina, Makkah during the peak period of Hajj and were asked to complete a baseline questionnaire that recorded their influenza vaccination history, including reason(s) for non-receipt of vaccine. RESULTS: A total of 6974 Saudi pilgrims aged between 18 and 95 (median 34) years were recruited; male to female ratio was 1:1.2. Of the total, 90.8% declared their influenza vaccination history, 51.3% of them reported receiving influenza vaccine before travel to Hajj. The vaccination rates for the years 2013, 2014 and 2015 were 21.4%, 48.2% and 58.1%, respectively (P < 0.001). Of 1,269 pilgrims who were at higher risk of severe disease, 54.5% received the vaccine. Lack of awareness (47.5%), reliance on natural immunity (15.8%) and being busy (15.5%) were the main reasons for non-receipt. CONCLUSION: These data from a convenience sample indicate that influenza vaccine uptake among Saudi Hajj pilgrims is increasing over years but still needs further improvement. Lack of awareness and misperceptions are the main barriers. Education of Saudi pilgrims and health professionals is required to raise awareness about influenza vaccination. Further studies are needed to understand pilgrims' misperceptions.