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.

Infectious causes of sudden infant death syndrome.

Investigators have long suspected the role of infection in sudden infant death syndrome (SIDS). Evidence of infectious associations with SIDS is accentuated through the presence of markers of infection and inflammation on autopsy of SIDS infants and isolates of some bacteria and viruses. Several observational studies have looked into the relation between seasonality and incidence of SIDS, which often showed a winter peak. These all may suggest an infectious aetiology of SIDS. In this review we have summarised the current literature on infectious aetiologies of SIDS by looking at viral, bacterial, genetic and environmental factors which are believed to be associated with SIDS.

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.

Epidemiological Differences in Hajj-Acquired Airborne Infections in Pilgrims Arriving from Low and Middle-Income versus High-Income Countries: A Systematised Review.

This systematised review aims to compare the epidemiological patterns of Hajj-acquired airborne infections among pilgrims from low and middle-income countries (LMIC) versus those from high-income countries (HIC). A PubMed search was carried out for all published articles before February 2023, using a combination of MeSH terms and text words. The Newcastle-Ottawa Scale (NOS) was used to assess data quality. From a total of 453 titles identified, 58 studies were included in the review (LMIC = 32, and HIC = 26). In the pooled sample, there were 27,799 pilgrims aged 2 days to 105 years (male: female = 1.3:1) from LMIC and 70,865 pilgrims aged 2 months to 95 years (male: female = 1:1) from HIC. Pilgrims from both HIC and LMIC had viral and bacterial infections, but pilgrims from HIC tended to have higher attack rates of viral infections than their LMIC counterparts. However, the attack rates of bacterial infections were variable: for instance, pilgrims from LMIC seemed to have higher rates of meningococcal infections (0.015-82% in LMIC vs. 0.002-40% in HIC) based on the study population, but not Mycobacterium tuberculosis (0.7-20.3% in LMIC vs. 38% in HIC). Targeted measures are needed to prevent the spread of airborne infections at Hajj.

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.

Effect of the COVID-19 Vaccine on the Menstrual Cycle among Females in Saudi Arabia.

Background: The number of reports of menstrual changes after COVID-19 vaccination in the Saudi population is still unknown. Therefore, this study aimed to assess the effect of the COVID-19 vaccine(Pfizer, AstraZeneca, and Moderna) on the menstrual cycle among females in Saudi Arabia. Methods: This descriptive cross-sectional study was conducted in Saudi Arabia at Umm Al-Qura University (UQU) from August 2021 to February 2022. Data was collected through a previously validated online questionnaire. Results: A total of 2338 participants who received the first dose of the COVID-19 vaccine participated in this study; 1606 (68.7%) of them received the second dose in addition to the first. The mean age of the study participants was 35.4±9.5 years. No significant associations were found between the type of COVID-19 vaccine and the impact on the menstrual cycle, either for the first or second dose (P-values > 0.05). A significant association was found only between the first dose vaccination day and the impact on the menstrual cycle in the second question of "After receiving the COVID-19 vaccine, your next period was" (P-value ≤ 0.05). Significant associations were found between the second dose vaccination day and the impact on the menstrual cycle in the first and second questions of "After receiving the COVID-19 vaccine, your next period was", and "After receiving the first dose, your next period was," respectively (P-values ≤ 0.05). Conclusion: The study found a potential association between the COVID-19 vaccine and menstrual cycle irregularities, which could impact females' quality of life.

Low Prevalence of Syndromic Respiratory Tract Infections among Returning Hajj Pilgrims Amidst the COVID-19 Pandemic: A Post-Hajj Survey.

This study estimates the point prevalence of symptomatic respiratory tract infections (RTIs) among returned Hajj pilgrims and their contacts in 2021. Using the computer-assisted telephone interview (CATI) technique, domestic pilgrims were invited to participate in this cross-sectional survey two weeks after their home return from Hajj. Of 600 pilgrims approached, 79.3% agreed to participate and completed the survey. Syndromic definitions were used to clinically diagnose possible influenza-like illnesses (ILI) and COVID-19. Median with range was applied to summarise the continuous data, and frequencies and proportions were used to present the categorical variables. Simple logistic regression was carried out to assess the correlations of potential factors with the prevalence of RTIs. The majority of pilgrims (88.7%) reported receiving at least two doses of the COVID-19 vaccine before Hajj. Eleven (2.3%) pilgrims reported respiratory symptoms with the estimated prevalence of possible ILI being 0.2%, and of possible COVID-19 being 0.4%. Among those who were symptomatic, five (45.5%) reported that one or more of their close contacts had developed similar RTI symptoms after the pilgrims' home return. The prevalence of RTIs among pilgrims who returned home after attending the Hajj 2021 was lower compared with those reported in the pre-pandemic studies; however, the risk of spread of infection among contacts following Hajj is still a concern.

The Impact of COVID-19 Pandemic on Obsession and Compulsion Symptoms in Saudi Arabia.

Background Obsessive-compulsive disorder (OCD) is a common condition that has a significant impact on people's lives. COVID-19 pandemic imposed a challenging situation for the general population with new precautionary measures. All that can have serious implications for those who already have intense concerns about cleanliness and hygiene and those diagnosed with OCD. The aim of this study was to examine the impact of the coronavirus disease 2019 (COVID-19) pandemic on the emergence and severity of obsession and compulsion symptoms in Saudi Arabia. Methods This was a cross-sectional study with 1,190 participants who completed an online three-part questionnaire that included sociodemographic data, the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) checklist, and (Y-BOCS) severity scale. On account of the fact that OCD requires a clinical evaluation to confirm the diagnosis, screening positive for OCD was defined based on criteria A of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which is selecting at least one of either obsession or compulsion symptoms or both. Screening positive for obsession was defined as selecting at least one of the obsessional symptoms while screening positive for compulsion was defined as selecting at least one of the compulsion symptoms. Results Overall, OCD screening was positive in 82% of participants. Previous diagnosis of OCD was reported by 2.6% (N=36) of the participants and 55.2% of them reported that their symptoms did not change during the pandemic, while 41.1% reported that their symptoms increased. Positive OCD screening was significantly higher in participants who reported previous psychological illness (87.6% vs. 80.9%), those who followed news related to COVID-19 on a daily basis (88.7% vs. 76.1%), and participants who had not acquired the infection (82.9%) compared to those who were infected with COVID-19 (72.3%). Conclusion The aim of this study was to determine the impact of the pandemic on OCD screening and symptoms. New OCD symptoms were reported in a high proportion of the participants. The results of this study can provide guidance for psychiatrists and psychologists in the clinical approach and management of patients with OCD. Further focused research on the factors affecting the emergence or severity of OCD symptoms needs to be conducted in the future.

Hand Hygiene Knowledge, Perception, and Practices among Domestic Visitors to the Prophet's Mosque in Al Madinah City Amid the COVID-19 Pandemic: A Cross-Sectional Study.

This study aimed to assess hand hygiene knowledge, perception, and practices of visitors to the Prophet's Mosque in Al Madinah City, Saudi Arabia. Using a self-administered electronic questionnaire, a cross-sectional survey was conducted among domestic residents, who visited the mosque between 31 July and 3 August 2020. Participants' demographic data, hand hygiene knowledge, perception, and practices were collected. Four hundred participants aged 18-65 (median 36) years completed the survey, of which 215 (53.8%) were female. The visitors' mean knowledge score about hand hygiene was 6.4 (± standard deviation (SD) 1.35) of total 12. Most participants (392, 98%) were aware of the role of hand hygiene in preventing Coronavirus Disease 2019 (COVID-19); nevertheless, 384 (96%) said hand hygiene lowers body immunity and 316 (79%) thought <60% alcohol is sufficient for hand disinfection. Males had a higher knowledge score than females (6.46 (±1.41) vs. 6.14 (±1.27), p = 0.02) and, visitors who had no formal education scored higher than those with post-graduate education (6.88 (±1.45) vs 5.73 (±1.12), p = 0.01). Washing hands with soap and water was the predominant method practiced after a meal (365, 91.7%), after toilet visit (354, 88.5%), after touching a surface (262, 65.7%), after waste disposal (332, 83.2%), and when hands were visibly dirty (357, 89.5%). Al Madinah visitors had moderate knowledge about hand hygiene, but demonstrated some knowledge gaps and negligence in practice that are crucial to curb the spread of COVID-19.

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.

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.

Acute respiratory tract infection symptoms and the uptake of dual influenza and pneumococcal vaccines among Hajj pilgrims.

BACKGROUND: Hajj pilgrims are encouraged to take influenza and pneumococcal vaccines prior to their travel to safeguard against acute respiratory tract infections (ARTIs). It is unclear whether dual immunisation with influenza and pneumococcal vaccines have had any impact on ARTI symptoms. To this end, we have examined the data of the last several years to assess whether combined influenza and pneumococcal vaccination has affected the rate of ARTI symptoms among Hajj pilgrims. MATERIALS AND METHODS: Hajj pilgrims from United Kingdom, Australia, Saudi Arabia and Qatar who attended the congregation between 2005 and 2015 were included in this study. Data from surveillance studies or clinical trials involving Hajj pilgrims were used. In this analysis we have made use of the raw data to construct a trend line graph with the prevalence of combined cough and fever (as a proxy for ARTI) against the uptake of combined influenza and pneumococcal vaccines, and to estimate the relative risk (RR) of ARTI with 95% confidence interval (95% CI). RESULTS: Data of a pooled sample of 9350 pilgrims, aged 0.5-90 years with a male to female ratio of 1.1, were analysed. Although vaccination uptake did not rise significantly over the years, there was also no observed meaningful benefit of combined vaccination (RR = 1.1; 95% CI 0.8-1.4), the rates of ARTI symptoms demonstrated a decline over the last several years. The findings of this analysis highlight that the prevalence of 'cough and fever' among Hajj pilgrims is on decline but the uptake of combined influenza and pneumococcal vaccines remains unchanged over years, and the decline can not be attributed to dual influenza and pneumococcal vaccination. CONCLUSIONS: Acute respiratory tract infections among Hajj pilgrims are decreasing, it is unclear if the reduction is due to vaccine uptake, but the data and analysis have some limitations.

Mismatching between circulating strains and vaccine strains of influenza: Effect on Hajj pilgrims from both hemispheres.

The trivalent seasonal influenza vaccine is expected to provide optimum protection if the vaccine strains match the circulating strains. The effect of worldwide mismatch between the vaccine strains and extant strains on travelers attending Hajj pilgrimage is not known. Annually 2-3 million Muslims coming from north and south hemispheres congregate at Hajj in Mecca, Saudi Arabia, where intense congestion amplifies the risk of respiratory infection up to eight fold. In order to estimate, to what extent mismatching increases the risk of vaccine failure in Hajj pilgrims, we have examined the global data on influenza epidemiology since 2003, in light of the available data from Hajj. These data demonstrate that globally mismatching between circulating and vaccine strains has occurred frequently over the last 12 years, and the mismatch seems to have affected the Hajj pilgrims, however, influenza virus characteristics were studied only in a limited number of Hajj seasons. When the vaccines are different, dual vaccination of travelers by vaccines for southern and northern hemispheres should be considered for Hajj pilgrims whenever logistically feasible. Consideration should also be given to the use of vaccines with broader coverage, i.e., quadrivalent, or higher immunogenicity. Continuous surveillance of influenza at Hajj is important.