Original Article--Mid-term Clinical and Hemodynamic Outcomes in Middle Age Patients Post Trifecta™ (Abbott) Aortic Valve Replacement: A Single-center Study.

Background: Trifecta™ is an externally wrapped bovine pericardial aortic valve with a favorable hemodynamic performance and acceptable rate of freedom from structural valve degeneration. However, recent reports of early Trifecta valve failure question its durability. Rheumatic valve disease in young population is predominant, there is no data on the Trifecta performance, durability or safety available worldwide over the middle age population, as well as there are no previous similar reports from Middle East region. We report on mid-term clinical and hemodynamic performance of Trifecta valve in middle age population with small aortic annuls, a single center report. Methods: A retrospective study of all patients who underwent Trifecta™ SAVR between June 2014 and December 2019 at a cardiac center in Riyadh, Saudi Arabia. Hemodynamic performance was analyzed by longitudinal Doppler echocardiography. Results: During a 5.5-year period, a total of 24 patients underwent SAVR with Trifecta™ valves at our heart center. Patients had a median age of 47.1 years (IQR = 37) and male:female ratio of 1:1. Patients had a median EuroScoreII of 2 (IQR = 1). The 19 mm valve was the most frequently used (29.2%) followed by the 21 mm and 23 mm (both 25.0%). Concomitant procedure was (54.2%). All patients survived their operations and most (87.0%) had their symptoms relieved. A 30-day mortality rate of 4.2%. Patients were followed up for a median of 58.5 months (IQR = 38), during which 8.3% required re interventions, giving an overall freedom from re-intervention of 91.7%. The re-intervention after valve implantation was recorded in two (8.3%). These re-interventions were performed 3 years post initial surgery and were due to structural valve deterioration (SVD). The mean gradient reduced significantly from 43.6 ± 23.9 mmHg (median = 41, IQR = 21) at baseline to 13.0 ± 7.4 mmHg (median = 11, IQR = 5) one-week post intervention (p < 0.001). The average mean gradients were stable from post-operation to follow-up (13.0 ± 7.4 vs 14.1 ± 6.4 mmHg). Conclusion: Our study confirms excellent mid-term durability, clinical and hemodynamic performance of the Trifecta™ valve in middle age population, despite the fact of non-statically significant trend-up of transvalvular gradient over the follow up period. Further long-term studies with larger sample-size are warranted to confirm these results.

Escalating climate-related health risks for Hajj pilgrims to Mecca.

BACKGROUND: Global temperatures are on the rise, leading to more frequent and severe heatwaves with associated health risks. Heat-related illnesses are an increasing threat for travellers to hot climate destinations. This study was designed to elucidate the interplay between increasing ambient temperatures, incidence of heat-related illnesses, and the effectiveness of mitigation strategies during the annual Hajj mass gathering over a 40-year period. METHODS: An observational study was conducted utilizing historical records spanning four decades of meteorological data, and the rates of heat stroke and heat exhaustion during the Hajj pilgrimage in Mecca, Saudi Arabia. With an annual population exceeding two million participants from over 180 countries, the study analyzed temporal variations in weather conditions over two distinct Hajj hot cycles and correlated it with the occurrence of heat stroke and heat exhaustion. The effectiveness of deployed mitigation measures in alleviating health vulnerabilities between the two cycles was also assessed. RESULTS: Throughout the study period, average dry and wet bulb temperatures in Mecca escalated by 0.4°C (Mann-Kendall p<0.0001) and 0.2°C (Mann-Kendall p=0.25) per decade respectively. Both temperatures were strongly correlated with the incidence of heat stroke and heat exhaustion (p<0.001). Despite the intensifying heat, the mitigation strategies including individual, structural and community measures were associated with a substantial 74.6% reduction in heat stroke cases and a 47.6% decrease in case fatality rate. CONCLUSION: The study underscores the escalating climate-related health risks in Mecca over the study period. The mitigation measures' efficacy in such a globally representative setting emphasizes the findings' generalizability and the importance of refining public health interventions in the face of rising temperatures.

Meningococcal disease in the Middle East: A report from the Global Meningococcal Initiative.

This review details recent findings from the Global Meningococcal Initiative's (GMI) recent meeting on the surveillance and control strategies for invasive meningococcal disease in the Middle East. The nature of case reporting and notification varies across the region, with many countries using bacterial meningitis as an IMD case definition in lieu of meningitis and septicaemia. This may overlook a significant burden associated with IMD leading to underreporting or misreporting of the disease. Based on these current definitions, IMD reported incidence remains low across the region, with historical outbreaks mainly occurring due to the Hajj and Umrah mass gatherings. The use of case confirmation techniques also varies in Middle Eastern countries. While typical microbiological techniques, such as culture and Gram staining, are widely used for characterisation, polymerase chain reaction (PCR) testing is utilised in a small number of countries. PCR testing may be inaccessible for several reasons including sample transportation, cost, or a lack of laboratory expertise. These barriers, not exclusive to PCR use, may impact surveillance systems more broadly. Another concern throughout the region is potentially widespread ciprofloxacin resistance since its use for chemoprophylaxis remains high in many countries.

Diagnosing and managing heat exhaustion: insights from a systematic review of cases in the desert climate of Mecca.

Heat exhaustion (HE) is a common, yet obscure, heat-related illness that affects millions of people yearly and its burden is projected to rise due to climate change. A comprehensive literature synthesis is lacking despite previous studies on various HE aspects. This systematic review aims to fill this gap by identifying and synthesizing available evidence on the risk factors, symptoms, biomarkers, treatment options, and outcomes for HE. The review focused on HE during the Muslim (Hajj) pilgrimage where the condition is endemic. We conducted a structured search of MEDLINE/PubMed, Embase, Web of Science Core Collection, SCOPUS, and CINAHL databases. We summarized the data from eligible studies and synthesized them in narrative form using pooled descriptive statistics. Ten studies were included between 1980 and 2019, reporting over 1,194 HE cases. HE cases presented with elevated core temperature (up to 40°C) and mainly affected older males from the Middle East and North Africa region, with overweight individuals at a higher risk. Clinical symptoms included hyperventilation, fatigue, dizziness, headaches, nausea, and vomiting, but not central nervous system disturbances. HE was associated with cardiac stress, and with water, electrolyte, and acid-base alterations. Cooling and hydration therapy were the primary management strategies, leading to a low mortality rate (pooled case fatality rate=0.11 % [95 % CI: 0.01, 0.3]). Most cases recovered within a few hours without complications. HE is associated with cardiac stress and changes in homeostasis, leading to distinct clinical symptoms. Early diagnosis and treatment of HE are crucial in reducing the risk of complications and mortality. The review provides insights into the pathophysiology and outcomes of HE, adding to the scarce literature on the subject. Prospero registration number: CRD42022325759.

Human tolerance to extreme heat: evidence from a desert climate population.

BACKGROUND: Ambient temperatures exceeding 40 °C are projected to become common in many temperate climatic zones due to global warming. Therefore, understanding the health effects of continuous exposure to high ambient temperatures on populations living in hot climatic regions can help identify the limits of human tolerance. OBJECTIVE: We studied the relationship between ambient temperature and non-accidental mortality in the hot desert city of Mecca, Saudi Arabia, between 2006 and 2015. METHODS: We used a distributed lag nonlinear model to estimate the mortality-temperature association over 25 days of lag. We determined the minimum mortality temperature (MMT) and the deaths that are attributable to heat and cold. RESULTS: We analyzed 37,178 non-accidental deaths reported in the ten-year study period among Mecca residents. The median average daily temperature was 32 °C (19-42 °C) during the same study period. We observed a U-shaped relationship between daily temperature and mortality with an MMT of 31.8 °C. The total temperature-attributable mortality of Mecca residents was 6.9% (-3.2; 14.8) without reaching statistical significance. However, extreme heat, higher than 38 °C, was significantly associated with increased risk of mortality. The lag structure effect of the temperature showed an immediate impact, followed by a decline in mortality over many days of heat. No effect of cold on mortality was observed. IMPACT STATEMENT: High ambient temperatures are projected to become future norms in temperate climates. Studying populations familiar with desert climates for generations with access to air-conditioning would inform on the mitigation measures to protect other populations from heat and on the limits of human tolerance to extreme temperatures. We studied the relationship between ambient temperature and all-cause mortality in the hot desert city of Mecca. We found that Mecca population is adapted to high temperatures, although there was a limit to tolerance to extreme heat. This implies that mitigation measures should be directed to accelerate individual adaptation to heat and societal reorganization.

Carriage of Neisseria meningitidis among travelers attending the Hajj pilgrimage, circulating serogroups, sequence types and antimicrobial susceptibility: A multinational longitudinal cohort study.

BACKGROUND: Travel to international mass gatherings such as the Hajj pilgrimage increases the risk of Neisseria meningitidis transmission and meningococcal disease. We investigated carriage and acquisition of N. meningitidis among travelers to Hajj and determined circulating serogroups, sequence types and antibiotic susceptibility among isolates. METHOD: We conducted a multinational longitudinal cohort study among 3921 traveling pilgrims in two phases: Pre-Hajj and Post-Hajj. For each participant, a questionnaire was administered and an oropharyngeal swab was obtained. N. meningitidis was isolated, serogrouped, and subjected to whole genome sequence analysis and antibiotic susceptibility testing. RESULTS: Overall carriage and acquisition rates of N. meningitidis were 0.74% (95%CI: 0.55-0.93) and 1.10% (95%CI: 0.77-1.42) respectively. Carriage was significantly higher Post-Hajj (0.38% vs 1.10%, p = 0.0004). All isolates were nongroupable, and most belonged to the ST-175 complex and were resistant to ciprofloxacin with reduced susceptibility to penicillins. Three potentially invasive isolates (all genogroup B) were identified in the Pre-Hajj samples. No factors were associated with Pre-Hajj carriage. Suffering influenza like illness symptoms and sharing a room with >15 people were associated with lower carriage Post-Hajj (adjOR = 0.23; p = 0.008 and adjOR = 0.27; p = 0.003, respectively). CONCLUSION: Carriage of N. meningitidis among traveler attending Hajj was low. However, most isolates were resistant to ciprofloxacin used for chemoprophylaxis. A review of the current meningococcal disease preventive measures for Hajj is warranted.

Association of Ambient Temperature with Mortality in Resident and Multiethnic Transient Populations in a Desert Climate, 2006-2014.

BACKGROUND: Although the association between ambient temperature and mortality in local populations is evident, this relationship remains unclear in transient populations (e.g., due to immigration, mass gatherings, or displacement). The holy city of Mecca annually shelters two populations comprising its residents and the transitory Hajj pilgrims (>2 million people from >180 countries). Both live side by side in a hot desert climate, rendering the development of evidence-based heat-protective measures challenging. OBJECTIVES: We aimed to characterize the ambient temperature-mortality relationship and burden for the Mecca resident and Hajj transient populations, which have distinct levels of adaptation to ambient temperature. METHODS: We analyzed daily air temperature and mortality data for Mecca residents and pilgrims over nine Hajj seasons between 2006 and 2014, using a fitted standard time-series Poisson model. We characterized the temperature-mortality relationship with a distributed lag nonlinear model with 10 d of lag. We determined the minimum mortality temperature (MMT) and attributable deaths for heat and cold for the two populations. RESULTS: The median average daily temperature during the Hajj seasons was 30°C (19°C-37°C). There were 8,543 and 10,457 nonaccidental deaths reported during the study period among Mecca residents and pilgrims, respectively. The MMT was 2.5°C lower for pilgrims in comparison with the MMT for Mecca residents (23.5°C vs. 26.0°C). The temperature-mortality relationship shape varied from inverted J to U shape for the Mecca and pilgrim populations, respectively. Neither hot nor cold temperatures had a statistically significant association with mortality in Mecca residents. In contrast, for pilgrims, elevated temperatures were associated with significantly high attributable mortality of 70.8% [95% confidence interval (CI): 62.8, 76.0]. The effect of heat on pilgrims was immediate and sustained. DISCUSSION: Our findings indicate that pilgrims and Mecca residents exposed to the same hot environmental conditions exhibited distinct health outcomes. This conclusion suggests that a precision public health approach may be warranted to protect against high environmental temperature during mass gatherings of diverse populations. https://doi.org/10.1289/EHP9838.

Undiagnosed and missed active pulmonary tuberculosis during mass gatherings: a prospective cross-sectional study from the Hajj pilgrimage.

Mass gatherings increase the risk of infectious diseases transmission including tuberculosis (TB). The Hajj pilgrimage to Mecca, Saudi Arabia, is attended by over 2 million pilgrims many of whom are from high TB-burden countries, and has been linked to increased risk of TB acquisition among travellers. We investigated the burden of undiagnosed and missed active pulmonary TB (PTB) among Hajj pilgrims symptomatic for cough. The study was conducted among hospitalised and non-hospitalised travellers attending the Hajj pilgrimage in 2016 and 2017. Questionnaires were used to collect relevant data and sputum samples were collected from participants and processed using the Xpert MTB-RIF assay. Non-hospitalised pilgrims (n = 1510) originating from 16 high and medium TB-burden countries were enrolled. Undiagnosed, rifampicin-sensitive, active PTB was identified in 0.7%. Comorbidities (adjOR = 5.9 [95% CI = 1.2-27.8]), close contact with a TB case (adjOR = 5.9 [95% CI = 1.2-27.8]), cough in household (adjOR = 4.46 [95% CI = 1.1-19.5]), and previous TB treatment (adjOR = 10.1 [95% CI = 4.1-98.1]) were independent risk factors for TB. Of the hospitalised pilgrims (n = 304), 2.9% were positive for PTB, and 2.3% were missed, including a rifampicin-resistant case. History of TB treatment was associated with increased risk of TB (adjOR = 8.1 [95% CI = 1.3-48.7]). International mass gatherings may play an important role in the global epidemiology of TB. Preventive measures should be directed to reducing the risk of TB importation and transmission during Hajj and other similar events.

Classic heat stroke in a desert climate: A systematic review of 2632 cases.

BACKGROUND: Although classic heat stroke (HS) is one of the most ancient conditions known to humans, the description of its early clinical manifestations, natural course, and complications remains uncertain. OBJECTIVES: A systematic review of the demographics, clinical characteristics, biomarkers, therapy, and outcomes of HS during the Muslim (Hajj) pilgrimage in the desert climate of Mecca, Saudi Arabia. METHODS: We searched the MEDLINE, Embase, Web of Science Core Collection, SCOPUS, and CINAHL databases from inception to April 2022. We summarized the data from eligible studies and synthesized them in narrative form using pooled descriptive statistics. RESULTS: Forty-four studies, including 2632 patients with HS, met the inclusion criteria. Overweight or obesity, diabetes, and cardiovascular disease were prevalent among cases of HS. Evidence suggests that extreme hyperthermia (pooled mean = 42.0°C [95% confidence interval (CI): 41.9, 42.1], range 40-44.8°C) with hot and dry skin (>99% of cases) and severe loss of consciousness (mean Glasgow Coma Scale <8 in 53.8% of cases) were the dominant clinical characteristics of classic HS. Hypotension, tachypnea, vomiting, diarrhea, and biochemical biomarkers indicating mild-to-moderate rhabdomyolysis, acute kidney, liver, heart injury, and coagulopathy were frequent at the onset. Concomitantly, stress hormones (cortisol and catecholamines) and biomarkers of systemic inflammation and coagulation activation were increased. HS was fatal in 1 in 18 cases (pooled case fatality rate = 5.6% [95%CI: 4.6, 6.5]). CONCLUSIONS: The findings of this review suggest that HS induces an early multiorgan injury that can progress rapidly to organ failure, culminating in death, if it is not recognized and treated promptly.

Whole genome transcriptomic reveals heat stroke molecular signatures in humans.

An evolutionary heat shock response (HSR) protects most living species, including humans, from heat-induced macromolecular damage. However, its role in the pathogenesis of heat stroke is unknown. We examined the whole genome transcriptome in peripheral blood mononuclear cells of a cohort of subjects exposed to the same high environmental heat conditions, who developed heat stroke (n = 19) versus those who did not (n = 19). Patients with heat stroke had a mean rectal temperature at admission of 41.7 ± 0.8°C, and eight were in deep coma (Glasgow Coma Score = 3). The transcriptome showed that genes involved in more than half of the entire chaperome were differentially expressed relative to heat stress control. These include the heat shock protein, cochaperone, and chaperonin genes, indicating a robust HSR. Differentially expressed genes also encoded proteins related to unfolded protein response, DNA repair, energy metabolism, oxidative stress, and immunity. The analysis predicted perturbations of the proteome network and energy production. Cooling therapy attenuated these alterations without complete restoration of homeostasis. We validated the significantly expressed genes by a real-time polymerase chain reaction. The findings reveal the molecular signature of heat stroke. They also suggested that a powerful HSR may not be sufficient to protect against heat injury. The overwhelming proteotoxicity and energy failure could play a pathogenic role. KEY POINTS: Most living species, including humans, have inherent heat stress response (HSR) that shields them against heat-induced macromolecular damage. The role of the HSR in subjects exposed to environmental heat who progressed to heat stroke versus those that did not is unknown. Our findings suggest that heat stroke induces a broad and robust HSR of nearly half of the total heat shock proteins, cochaperones, and chaperonin genes. Heat stroke patients exhibited inhibition of genes involved in energy production, including oxidative phosphorylation and ATP production. Significant enrichment of neurodegenerative pathways, including amyloid processing signalling, the Huntington's and Parkinson's disease signalling suggestive of brain proteotoxicity was noted. The data suggests that more than a powerful HSR may be required to protect against heat stroke. Overwhelming proteotoxicity and energy failure might contribute to its pathogenesis.

Risk factors for heat-related illnesses during the Hajj mass gathering: an expert review.

Human exposure to a hot environment may result in various heat-related illnesses (HRIs), which range in severity from mild and moderate forms to life-threatening heatstroke. The Hajj is one of the largest annual mass gatherings globally and has historically been associated with HRIs. Hajj attracts over two million Muslim pilgrims from more than 180 countries to the holy city of Makkah, Kingdom of Saudi Arabia. Several modifiable and non-modifiable factors render Hajj pilgrims at increased risk of developing HRIs during Hajj. These include characteristics of the Hajj, its location, population, and rituals, as well as pilgrims' knowledge of HRIs and their attitude and behavior. Makkah is characterized by a hot desert climate and fluctuating levels of relative humidity. Pilgrims are very diverse ethnically and geographically, with different adaptations to heat. Significant proportions of the Hajj population are elderly, obese, and with low levels of fitness. In addition, many have underlying health conditions and are on multiple medications that can interfere with thermoregulation. Other factors are inherent in the Hajj and its activities, including crowding, physically demanding outdoor rituals, and a high frequency of infection and febrile illness. Pilgrims generally lack awareness of HRIs, and their uptake of preventive measures is variable. In addition, many engage in hazardous behaviors that increase their risk of HRIs. These include performing rituals during the peak sunshine hours with no sun protection and with suboptimal sleep, nutrition, and hydration, while neglecting treatment for their chronic conditions. HRIs preventive plans for Hajj should incorporate measures to address the aforementioned factors to reduce the burden of these illnesses in future Hajj seasons. Lessons from the Hajj can be used to inform policy making and HRIs preventive measures in the general population worldwide.

Respiratory pathogens among ill pilgrims and the potential benefit of using point-of-care rapid molecular diagnostic tools during the Hajj.

We investigated respiratory pathogens among ill Hajj pilgrims from Marseille. We also discuss the potential role of point-of-care (POC) rapid molecular diagnostic tools for this purpose. Clinical data were collected using a standardised questionnaire. Influenza A and B viruses, human rhinovirus and human coronaviruses, Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae and Klebsiella pneumoniae were investigated using real-time PCR in respiratory samples obtained during travel, at the onset of symptoms. 207 participants were included. A cough, expectoration, rhinitis and a sore throat were the most frequent respiratory symptoms, followed by loss of voice and dyspnoea. 38.7% and 25.1% of pilgrims reported a fever and influenza-like symptoms, respectively. 59.4% pilgrims received antibiotics. Rhinovirus (40.6%) was the most frequent pathogen, followed by S. aureus (35.8%) and H. influenzae (30.4%). Virus and bacteria co-infections were identified in 28.5% of participants. 25.1% pilgrims who were positive for respiratory bacteria did not receive antibiotic treatment. In the context of the Hajj pilgrimage, it is important to detect infections that can be easily managed with appropriate treatment, and those that can affect prognosis, requiring hospitalisation. POC rapid molecular diagnostic tools could be used for patient management at small Hajj medical missions and to rationalise antibiotic consumption among Hajj pilgrims.

Carriage of Neisseria meningitidis Among Umrah Pilgrims: Circulating Serogroups and Antibiotic Resistance.

Background: Meningococcal disease and outbreaks are a risk during mass gatherings such as the Umrah religious pilgrimage to the Kingdom of Saudi Arabia (KSA). We aimed to investigate the carriage of Neisseria meningitidis among the 2019 Umrah pilgrims and determine the circulating serogroups and their antibiotic susceptibility profiles. Methods: We conducted a cross-sectional study among adult Umrah pilgrims from 17th to 29th April 2019 in Mecca city, KSA. A questionnaire was administered to each participant, and an oropharyngeal swab was obtained. Microbiological techniques were used to isolate, identify and serogroup N. meningitidis from the swabs. E-tests were used to determine the susceptibility of the isolates to nine antibiotics. Results: The study enrolled 616 pilgrims from 17 countries with a mean age of 53.8 years (±13.1, range = 19-91) and a male-to-female ratio of 1.1:1. Nearly 39% of the respondents had no formal education, 32.5% declared having an underlying health condition and 17.2% were current or past smokers. During their Umrah stay, most pilgrims reported sharing accommodation (98.5%) and never using a face mask (98.5%). Also, 34.6% reported suffering from influenza-like symptoms and 11.8% used antibiotics. N. meningitidis was isolated from three pilgrims (carriage rate of 0.49%), two were serogroup A and one was serogroup B. Antibiotic susceptibility results were available for one isolate (serogroup B) which showed resistance to ciprofloxacin and decreased susceptibility to trimethoprim-sulfamethoxazole. Conclusion: Carriage of N. meningitidis among Umrah pilgrims was low. However, invasive serogroups were identified, including an isolate resistant to ciprofloxacin used for chemoprophylaxis. Meningococcal disease preventive measures for Umrah should be regularly reviewed and updated accordingly to reduce the risk of the disease and future pilgrimage-associated outbreaks.

Pattern of utilization, disease presentation, and medication prescribing and dispensing at 51 primary healthcare centers during the Hajj mass gathering.

BACKGROUND: The majority of pilgrims seeking healthcare during Hajj are seen at primary healthcare centers (PHCCs). Data on the utilization of these facilities during Hajj can aid in directing optimal health services delivery and allocation of resources during the pilgrimage. METHOD: We investigated the pattern of disease presentation, caseload, and medication prescribing and dispensing at 51 PHCCs during the 2019 Hajj. Data on patients' demographics, diagnoses, and prescribed medications were retrieved from each PHCC's electronic records and analyzed. Data were also used to calculate six of the World Health Organization (WHO) indicators for drug use at these facilities. RESULTS: Data were captured for 99,367 patients who were mostly Hajj pilgrims (95.4%), male (69.1%) from the Eastern Mediterranean (60.8%) and had a mean age of 46.6 years (SD = 14.9). Most patients (85.2%) were seen in Mina and towards the end of Hajj. The majority of patients (96.0%) had a single diagnosis; most commonly, respiratory (45.0%), musculoskeletal (17.2%), and skin (10.5%) diseases. Patients were prescribed 223,964 medications, mostly analgesics (25.1%), antibacterials for systemic use (16.5%), anti-inflammatory and antirheumatic products (16.4%), and cough and cold preparations (11.9%). On average, 2.25 (SD = 0.94) medications were prescribed per consultation, with low (1.3%) prevalence of polypharmacy. An antibiotic and an injectable were prescribed in 43.6 and 2.67% of patient encounters, respectively. Most (92.7%) of the prescribed drugs were actually dispensed, in an average time of 8.06 min (SD = 41.4). All PHCCs had a copy of the essential drugs list available, on which all the prescribed drugs appeared. CONCLUSION: Respiratory illnesses are the main reason for PHCCs visits during Hajj, and analgesics and antibiotics are the most common medications prescribed to pilgrims. Our results, including the calculated WHO drug use indicators, contribute to evidence-based optimization of primary healthcare services during Hajj.

Potential Cross-Reactive Immunity to COVID-19 Infection in Individuals With Laboratory-Confirmed MERS-CoV Infection: A National Retrospective Cohort Study From Saudi Arabia.

BACKGROUND: A growing number of experiments have suggested potential cross-reactive immunity between severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and previous human coronaviruses. We conducted the present retrospective cohort study to investigate the relationship between previous Middle East respiratory syndrome-coronavirus (MERS-CoV) infection and the risk of SARS-CoV-2 infection as well as the relationship between previous MERS-CoV and COVID-19-related hospitalization and mortality. METHODS: Starting in March 2020, we prospectively followed two groups of individuals who tested negative for COVID-19 infection. The first group had a previously confirmed MERS-CoV infection, which was compared to a control group of MERS-negative individuals. The studied cohort was then followed until November 2020 to track evidence of contracting COVID-19 infection. FINDINGS: A total of 82 (24%) MERS-positive and 260 (31%) MERS-negative individuals had COVID-19 infection. Patients in the MERS-positive group had a lower risk of COVID-19 infection than those in the MERS-negative group (Risk ratio [RR] 0.696, 95% confidence interval [CI] 0.522-0.929; p =0.014). The risk of COVID-19-related hospitalization in the MERS-positive group was significantly higher (RR 4.036, 95% CI 1.705-9.555; p =0.002). The case fatality rate (CFR) from COVID-19 was 4.9% in the MERS-positive group and 1.2% in the MERS-negative group (p =0.038). The MERS-positive group had a higher risk of death than the MERS-negative group (RR 6.222, 95% CI 1.342-28.839; p =0.019). However, the risk of mortality was similar between the two groups when death was adjusted for age (p =0.068) and age and sex (p =0.057). After controlling for all the independent variables, only healthcare worker occupation and >1 comorbidity were independent predictors of SARS-CoV-2 infection. INTERPRETATION: Individuals with previous MERS-CoV infection can exhibit a cross-reactive immune response to SARS-CoV-2 infection. Our study demonstrated that patients with MERS-CoV infection had higher risks of COVID-19-related hospitalization and death than MERS-negative individuals.

Novel Respiratory Viruses in the Context of Mass-Gathering Events: A Systematic Review to Inform Event Planning from a Health Perspective.

BACKGROUND: Mass-gathering events (MGEs) occur regularly throughout the world. As people congregate at MGEs, there is an increased risk of transmission of communicable diseases. Novel respiratory viruses, such as Severe Acute Respiratory Syndrome Coronavirus-1 (SARS-CoV-1), Influenza A Virus Subtype H1N1 Strain 2009 (H1N1pdm09), Middle East Respiratory Syndrome Coronavirus (MERS-CoV), and Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), or Coronavirus Disease 2019 (COVID-19), may require specific infection prevention and control strategies to minimize the risk of transmission when planning MGEs. This literature review aimed to identify and analyze papers relating to novel respiratory viruses with pandemic potential and to inform MGE planning. METHOD: This paper used a systematic literature review method. Various health care databases were searched using keywords relating to MGEs and novel respiratory viruses. Information was extracted from identified papers into various tables for analysis. The analysis identified infection prevention and control strategies used at MGEs to inform planning before, during, and following events. RESULTS: In total, 27 papers met the criteria for inclusion. No papers were identified regarding SARS-CoV-1, while the remainder reported on H1N1pdm09 (n = 9), MERS-CoV (n = 15), and SARS-CoV-2 (n = 3). Various before, during, and after event mitigation strategies were identified that can be implemented for future events. CONCLUSIONS: This literature review provided an overview of the novel respiratory virus epidemiology at MGEs alongside related public health mitigation strategies that have been implemented at these events. This paper also discusses the health security of event participants and host communities in the context of cancelling, postponing, and modifying events due to a novel respiratory virus. In particular, ways to recommence events incorporating various mitigation strategies are outlined.

Knowledge, Attitude, and Perceived Risks Towards COVID-19 Pandemic and the Impact of Risk Communication Messages on Healthcare Workers in Saudi Arabia.

PURPOSE: To investigate knowledge, attitude, and perceived risks towards COVID-19 pandemic among healthcare workers (HCWs) in Saudi Arabia. Besides, the impact of risk communication strategy on the attitude and practice of HCWs was investigated. PATIENTS AND METHODS: We conducted a cross-sectional study that targeted HCWs from various Saudi health facilities. We utilized a self-administrated, online-based questionnaire designed to assess basic knowledge of COVID-19, attitude and disease perception, and the impact of risk communication messages among HCWs. RESULTS: A total of 1691 responses were received in the study. The HCWs exhibited good levels of knowledge (total maximum score is 1) of COVID-19 concerning the modes of transportation of COVID-19 (0.82±0.16), sample collection method for COVID-19 diagnosis (0.98±0.08), transmission of infection from asymptomatic individuals (0.99±0.11), and that antibiotics are not effective against the new COVID-19 (0.83±0.38). Nearly one-third of the participants considered a high/very high possibility of acquiring COVID-19 infection. HCWs had good attitude scores concerning their willingness to deal with new COVID-19 patients (0.87±0.33) and their beliefs in being educated on COVID-19 (0.99±0.11). Almost all participants strongly agree/agree that it is important to take action to prevent the spread of COVID-19 within healthcare facilities and received health information messages. Notably, 93.4% of the participants stated that the received messages changed their attitude towards COVID-19 and its preventive measures. Good knowledge scores were significantly associated with age > 49 years old, higher educational level, and physician occupation. Similarly, good attitude scores were higher among males, HCWs aged 40-49 years old, non-Saudi nationals, and physician and nurse occupations. CONCLUSION: HCWs have fair knowledge and attitude towards the COVID-19 pandemic. The risk communication is an effective strategy to improve the attitude and practice of HCWs towards COVID-19 in Saudi Arabia.

Gastrointestinal symptoms and knowledge and practice of pilgrims regarding food and water safety during the 2019 Hajj mass gathering.

BACKGROUND: Food and water-borne diseases (FWBDs) are a health risk at the Hajj mass gathering. The current study documented the prevalence and management of gastrointestinal (GI) symptoms among pilgrims during the 2019 Hajj and assessed their knowledge and practice concerning food and water safety. METHOD: An analytical cross-sectional study was conducted in Macca, Saudi Arabia, among adult Hajj pilgrims from 28 countries. Data was collected from 15th-20th August 2019 by facer-to-face interviews using an anonymous structured questionnaire. Basic demographic data as well as information regarding pilgrims' knowledge and practice relating to food and water safety and any GI symptoms experienced during the Hajj was collected and analyzed. RESULTS: The study enrolled 1363 pilgrims with a mean age of 50.1 years (SD = 12.3) and 63.4% (n = 845) were male. At least 9.7% (n = 133) of pilgrims experience GI symptoms and 5.1% (69/1363) suffered diarrhea. Most respondents drunk bottled water (99.4%, n = 1324) and obtained their food from their hotel /Hajj mission (> 86%). In general, pilgrims had good knowledge and practice in relation to food and water safety, although risky practices were noted concerning keeping food at unsafe temperatures and hazardous sharing of food and water. Gender, nationality and suffering GI symptoms during Hajj were significantly associated with good knowledge and good practice. There was a moderate but statistically significant positive correlation between knowledge and practice scores (rs = 0.41, p < 0.0001). CONCLUSION: Despite overall good knowledge and self-reported practice, risky behaviors relating to food and water safety were identified among pilgrims, many of whom suffered from GI symptoms during Hajj. Our results can form the basis for developing tailored, targeted and effective interventions to improve pilgrims' knowledge and behavior and reduce the burden of FWBDs at the Hajj and beyond.

Lack of Zika Virus and Other Recognized Flaviviruses among the Mosquito Vectors during and Post the Hajj Mass Gathering.

Makkah city, Kingdom of Saudi Arabia (KSA), contains many of the world's mosquito vectors of parasitic and arboviral disease and is the site of the Hajj mass gathering. As such there is a risk of exportation and globalization of vector-borne viruses, including the re-emerging Zika virus (ZIKV). There was international concern regarding the introduction of ZIKV to KSA and potential international spread of the virus following the 2016 Hajj which took place few days after the Rio summer Olympics at the height of the ZIKV pandemic. We aimed to detect flaviviruses, including ZIKV, circulating among mosquito hosts in the city of Makkah during and post the 2016 Hajj pilgrimage. Mosquitos (adults and larvae) were sampled from 15 sites in Makkah city during and post the 2016 Hajj and identified to species by morphological keys. Mosquitos were pooled according to date of collection, location, and species. A Pan-Flaviviruses RT-PCR assay that enables identification of 51 flaviviruses species and three tentative species was used to detect flavivirus RNA directly from mosquito homogenates. Between the 10 September and 6 October 2016, 9412 female mosquitos were collected. Of these, 81.3% were Aedes aegypti, 18.6% were Culex species, and 0.1% were Anopheles species. Of the total 493 mosquito pools generated, 242 (49%) were positive by the Pan-Flaviviruses primer set. Sequence analysis revealed that none of the mosquitos carried a pathogenic flavivirus, including ZIKV, but were infected with a novel insect-specific flavivirus. We found no pathogenic flaviviruses circulating in Makkah city during and post the 2016 Hajj and no evidence of introduction of ZIKV through the pilgrimage. Enhanced vector-borne diseases surveillance, prevention, and control are crucial in KSA especially during international mass gatherings such as the annual Hajj to prevent outbreaks and the spread of viruses with epidemic and pandemic potentials.

Medication Handling and Storage among Pilgrims during the Hajj Mass Gathering.

We aimed to investigate the knowledge and practices of Hajj pilgrims regarding medication storage and handling during the Hajj mass gathering. In this cross-sectional study, adult pilgrims from 30 countries were interviewed using a structured questionnaire during the 2019 Hajj. The study enrolled 1221 participants with a mean age of 50.8 years (SD = 12.5, range = 18-98) and male:female ratio of 1.7:1. Most pilgrims were literate, 50.4% had a university or higher education, and 38% reported at least one underlying health condition. Most pilgrims reported receiving education regarding the proper way to store their medication during Hajj, mainly from physicians (73.7%) and pharmacists (39.4%). Although 68.2% of pilgrims had good knowledge regarding medication storage and the potential effect of inappropriate storage conditions on medications and health, inadequate knowledge and poor practice were identified among some. Level of education, having an underlying health condition and receiving health education on mediation storage were independently associated with good knowledge. Most pilgrims took their medications with them during Hajj, although storage and handling of their medication also varied depending on the stages of their Hajj pilgrimage journey. Improving Hajj pilgrims' awareness and knowledge about appropriate storage and handling of their medications are beneficial in reducing the risk of associated adverse health outcomes, both during Hajj and beyond the mass gathering.