{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T17:25:55Z","timestamp":1792085155653,"version":"4.4.0"},"reference-count":40,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T00:00:00Z","timestamp":1762128000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015624","name":"University of Jeddah, Jeddah, Saudi Arabia","doi-asserted-by":"publisher","award":["UJ-24-SUTU-885"],"award-info":[{"award-number":["UJ-24-SUTU-885"]}],"id":[{"id":"10.13039\/501100015624","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Little is known about morbidity patterns and healthcare utilization among specific Hajj pilgrim groups. This study examined influenza vaccination coverage, disease spectrum and healthcare utilization outcomes among Sudanese pilgrims during Hajj 2025. Methods: A cross-sectional analysis was conducted using de-identified patient records from the Saudi Health Electronic Surveillance Network for Sudanese Hajj pilgrims in 1\u20139 June 2025. Data included demographics, influenza vaccination status, healthcare utilization metrics, morbidities and temporal distribution of visits. Comparisons between hospital and primary healthcare center (PHC) attendees were performed using appropriate statistical tests. Results: A total of 1130 pilgrims sought care, with 88.6% (n = 1001) attending PHCs and 11.4% (n = 129) hospitals. Their mean age was 49.7 \u00b1 12.9 years, and 67.9% (n = 767) were male. Influenza vaccination coverage was 79% (893\/1130); vaccinated pilgrims had lower incidence of influenza-like illness (ILI) compared to unvaccinated pilgrims (5.2% vs. 15.2%, p &lt; 0.01). Respiratory illnesses were the most frequent diagnoses (40.8% in PHCs and 24.8% in hospitals), followed by musculoskeletal disorders (24.5% and 16.3%, respectively). Compared to PHCs, presentation rate for chronic diseases was higher in hospitals (19.4% vs. 8.7%, p &lt; 0.001), so was the median clinic time (14.1 vs. 8.6 min, p &lt; 0.001). Healthcare utilization peaked on days 3\u20135 coinciding with the \u2018Arafat Day\u2019. Conclusions: Sudanese pilgrims most commonly presented with acute respiratory conditions, with PHCs managing the majority of cases, and influenza vaccination was protective against ILI. Findings emphasize the need for strong primary care, efficient resource allocation, and targeted preventive strategies to safeguard pilgrims\u2019 health in the future.<\/jats:p>","DOI":"10.3390\/vaccines13111134","type":"journal-article","created":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T16:18:42Z","timestamp":1762186722000},"page":"1134","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Influenza Vaccination and Morbidity Among Sudanese Hajj Pilgrims During the 2025 Hajj"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2163-004X","authenticated-orcid":false,"given":"Najim Z.","family":"Alshahrani","sequence":"first","affiliation":[{"name":"Department of Family and Community Medicine, College of Medicine, University of Jeddah, Jeddah 23218, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0554-4790","authenticated-orcid":false,"given":"Mohammed R.","family":"Algethami","sequence":"additional","affiliation":[{"name":"Department of Family and Community Medicine, College of Medicine, University of Jeddah, Jeddah 23218, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdulrahman M.","family":"Albeshry","sequence":"additional","affiliation":[{"name":"Department of Family and Community Medicine, College of Medicine, University of Jeddah, Jeddah 23218, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zuhier","family":"Awan","sequence":"additional","affiliation":[{"name":"College of Applied Medical Sciences, University of Jeddah, Jeddah 23218, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wael","family":"AlZhrani","sequence":"additional","affiliation":[{"name":"Population Health Management, Jeddah First Health Cluster, Health Holding Company, Jeddah 21429, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Osama A.","family":"Bugis","sequence":"additional","affiliation":[{"name":"Population Health Management, Jeddah First Health Cluster, Health Holding Company, Jeddah 21429, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah Jaber","family":"Alsahafi","sequence":"additional","affiliation":[{"name":"Population Health Management, Jeddah First Health Cluster, Health Holding Company, Jeddah 21429, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2286-5139","authenticated-orcid":false,"given":"Harunor","family":"Rashid","sequence":"additional","affiliation":[{"name":"Children\u2019s Hospital Westmead Clinical School, Sydney Infectious Diseases Institute, University of Sydney, Westmead, Sydney, NSW 2145, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"868","DOI":"10.15537\/smj.2017.8.20124","article-title":"Umrah. An opportunity for mass gatherings health research","volume":"38","author":"Yezli","year":"2017","journal-title":"Saudi Med. J."},{"key":"ref_2","unstructured":"(2025, August 28). GASTAT: Total Number of Pilgrims Performing Hajj 1446H (2025) Reaches (1,673,230), Available online: https:\/\/www.stats.gov.sa\/en\/w\/news\/49."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1016\/j.tmaid.2015.12.008","article-title":"Hajj-associated viral respiratory infections: A systematic review","volume":"14","author":"Gautret","year":"2015","journal-title":"Travel. Med. Infect. Dis."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"100017","DOI":"10.1016\/j.mgmed.2025.100017","article-title":"International Health Regulations (IHR) and the success story of public health preparedness during Hajj in Saudi Arabia","volume":"3","author":"Alshahrani","year":"2025","journal-title":"Mass Gather. Med."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1136\/bmj.330.7483.133","article-title":"Hajj: Journey of a lifetime","volume":"330","author":"Gatrad","year":"2005","journal-title":"BMJ"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"744","DOI":"10.26719\/2019.25.10.744","article-title":"Health issues in the hajj pilgrimage: A literature review","volume":"25","author":"Aldossari","year":"2019","journal-title":"East. Mediterr. Health J."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1008","DOI":"10.1016\/S0140-6736(06)68429-8","article-title":"Health risks at the Hajj","volume":"367","author":"Ahmed","year":"2006","journal-title":"Lancet"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1016\/j.jiph.2023.05.021","article-title":"Epidemiology of Hajj pilgrimage mortality: Analysis for potential intervention","volume":"17","author":"Gaddoury","year":"2024","journal-title":"J. Infect. Public Health"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"100099","DOI":"10.1016\/j.dialog.2023.100099","article-title":"Prevalence of emergency cases among pilgrims presenting at King Abdulaziz International Airport Health Care Center at Hajj Terminal, Jeddah, Saudi Arabia during Hajj Season, 1440 H\u20142019","volume":"2","author":"Alrufaidi","year":"2023","journal-title":"Dialogues Health"},{"key":"ref_10","unstructured":"(2025, September 10). List of Hospitals in Mina Where Pilgrims Can Receive Medical Services\u2014Hajj Reporters. Available online: https:\/\/hajjreporters.com\/list-of-hospitals-in-mina-where-pilgrims-can-receive-medical-services\/."},{"key":"ref_11","unstructured":"(2025, September 10). MOH News\u2014MOH: 4 Hospitals and 26 Healthcare Centers in Mina Ready to Serve Pilgrims on the Day of At-Tarwiyah, Available online: https:\/\/www.moh.gov.sa\/en\/Ministry\/MediaCenter\/News\/Pages\/News-2022-07-06-001.aspx."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/S1473-3099(11)70337-1","article-title":"Emergence of medicine for mass gatherings: Lessons from the Hajj","volume":"12","author":"Memish","year":"2012","journal-title":"Lancet Infect. Dis."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/j.jiph.2008.08.008","article-title":"Hajj: Health lessons for mass gatherings","volume":"1","author":"Shafi","year":"2008","journal-title":"J. Infect. Public Health"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"tay070","DOI":"10.1093\/jtm\/tay070","article-title":"Strengthening health security at the Hajj mass gatherings: A Harmonised Hajj Health Information System","volume":"25","author":"Yezli","year":"2018","journal-title":"J. Travel. Med."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"taae122","DOI":"10.1093\/jtm\/taae122","article-title":"Sacred journeys and pilgrimages: Health risks associated with travels for religious purposes","volume":"31","author":"Parker","year":"2024","journal-title":"J. Travel. Med."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1016\/j.aogh.2016.12.001","article-title":"Mass Gatherings and Public Health: Case Studies from the Hajj to Mecca","volume":"83","author":"Rahman","year":"2017","journal-title":"Ann. Glob. Health"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"260","DOI":"10.1016\/S0140-6736(89)90439-X","article-title":"Intercontinental spread of an epidemic group A Neisseria meningitidis strain","volume":"2","author":"Moore","year":"1989","journal-title":"Lancet"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Mushi, A., Yassin, Y., Khan, A., Alotaibi, B., Parker, S., Mahomed, O., and Yezli, S. (2021). A Longitudinal Study Regarding the Health Profile of the 2017 South African Hajj Pilgrims. Int. J. Environ. Res. Public Health, 18, Available online: https:\/\/www.mdpi.com\/1660-4601\/18\/7\/3607\/htm.","DOI":"10.3390\/ijerph18073607"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1111\/irv.12429","article-title":"Cross-sectional survey and surveillance for influenza viruses and MERS-CoV among Egyptian pilgrims returning from Hajj during 2012\u20132015","volume":"11","author":"Refaey","year":"2017","journal-title":"Influenza Other Respir Viruses"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Mahdi, H.A., Alluhidan, M., Almohammed, A.B., Alfelali, M., Shaban, R.Z., Booy, R., and Rashid, H. (2023). Epidemiological Differences in Hajj-Acquired Airborne Infections in Pilgrims Arriving from Low and Middle-Income versus High-Income Countries: A Systematised Review. Trop. Med. Infect. Dis., 8, Available online: https:\/\/www.mdpi.com\/2414-6366\/8\/8\/418\/htm.","DOI":"10.3390\/tropicalmed8080418"},{"key":"ref_21","unstructured":"(2025, October 22). Global Influenza Programme. Available online: https:\/\/www.who.int\/teams\/global-influenza-programme\/surveillance-and-monitoring\/case-definitions-for-ili-and-sari?utm_source=chatgpt.com."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"50","DOI":"10.4103\/1817-1737.49412","article-title":"Respiratory tract infection during Hajj","volume":"4","author":"Alzeer","year":"2009","journal-title":"Ann. Thorac. Med."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Yezli, S., Yassin, Y., Mushi, A., Almuzaini, Y., and Khan, A. (2022). Pattern of utilization, disease presentation, and medication prescribing and dispensing at 51 primary healthcare centers during the Hajj mass gathering. BMC Health Serv. Res., 22, Available online: https:\/\/pubmed.ncbi.nlm.nih.gov\/35115010\/.","DOI":"10.1186\/s12913-022-07507-3"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"12622","DOI":"10.1038\/s41598-024-62682-z","article-title":"Morbidity amongst South African Hajj pilgrims in 2023\u2014A retrospective cohort study","volume":"14","author":"Mahomed","year":"2024","journal-title":"Sci. Rep."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"571.e1","DOI":"10.1016\/j.cmi.2015.02.008","article-title":"Mass gathering and globalization of respiratory pathogens during the 2013 Hajj","volume":"21","author":"Memish","year":"2015","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Kattan, W. (2024). The state of primary healthcare centers in Saudi Arabia: A regional analysis for 2022. PLoS ONE, 19, Available online: https:\/\/journals.plos.org\/plosone\/article?id=10.1371\/journal.pone.0301918.","DOI":"10.1371\/journal.pone.0301918"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/j.ijid.2016.05.024","article-title":"Hajj vaccinations\u2014Facts, challenges, and hope","volume":"47","author":"Sharaf","year":"2016","journal-title":"Int. J. Infect. Dis."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1007\/s44443-025-00095-2","article-title":"From data to insights: A comprehensive analysis of pilgrims stress and fatigue during Hajj using wearable remote sensing systems","volume":"37","author":"Alshamrani","year":"2025","journal-title":"J. King Saud Univ. \u2014Comput. Inf. Sci."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2233","DOI":"10.2147\/RMHP.S521097","article-title":"Health Risk Behaviors and Associated Factors Among Hajj 2024 Pilgrims: A Multinational Cross-Sectional Study","volume":"18","author":"Samarkandi","year":"2025","journal-title":"Risk Manag Heal. Policy"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"781","DOI":"10.12669\/pjms.344.15989","article-title":"Patterns of Inpatient Admissions during Hajj: Clinical conditions, length of stay and patient outcomes at an advanced care centre in Makkah, Saudi Arabia","volume":"34","author":"Mirza","year":"2018","journal-title":"Pak. J. Med. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"100019","DOI":"10.1016\/j.mgmed.2025.100019","article-title":"Pilgrimage and prevention: Closing meningococcal gaps ahead of Hajj 2025","volume":"3","author":"Alshahrani","year":"2025","journal-title":"Mass Gathering Med."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"924","DOI":"10.1001\/jamainternmed.2023.2629","article-title":"Temporal Clustering of Critical Illness Events on Medical Wards","volume":"183","author":"Doshi","year":"2023","journal-title":"JAMA Intern. Med."},{"key":"ref_33","first-page":"e56754","article-title":"The Prevalence of Musculoskeletal Injuries Among Pilgrims During the 2023 Hajj Season: A Cross-Sectional Study","volume":"16","author":"Alghamdi","year":"2024","journal-title":"Cureus"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Yezli, S., Yassin, Y., Mushi, A., Aburas, A., Alabdullatif, L., Alburayh, M., and Khan, A. (2021). Gastrointestinal symptoms and knowledge and practice of pilgrims regarding food and water safety during the 2019 Hajj mass gathering. BMC Public Health, 21, Available online: https:\/\/bmcpublichealth.biomedcentral.com\/articles\/10.1186\/s12889-021-11381-9.","DOI":"10.1186\/s12889-021-11381-9"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Alnafisah, R., Alnasiri, F., Alzaharni, S., Alshikhi, I., and Alqahtani, A. (2023). Food Safety Practices during Hajj: On-Site Inspections of Food-Serving Establishments. Trop. Med. Infect. Dis., 8, Available online: https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC10610560\/.","DOI":"10.3390\/tropicalmed8100480"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2562","DOI":"10.1016\/j.vaccine.2015.04.006","article-title":"Changes in the prevalence of influenza-like illness and influenza vaccine uptake among Hajj pilgrims: A 10-year retrospective analysis of data","volume":"33","author":"Alfelali","year":"2015","journal-title":"Vaccine"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Tian, Y., Ma, Y., Ran, J., Yuan, L., Zeng, X., Tan, L., Chen, L., Xu, Y., Li, S., and Huang, T. (2024). Protective Impact of Influenza Vaccination on Healthcare Workers. Vaccines, 12, Available online: https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC11599008\/.","DOI":"10.3390\/vaccines12111237"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1016\/j.cmi.2014.11.026","article-title":"Vaccinations against respiratory tract infections at Hajj","volume":"21","author":"Alqahtani","year":"2015","journal-title":"Clin. Microbiol. Infect."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"100009","DOI":"10.1016\/j.mgmed.2024.100009","article-title":"AI-powered predictive analytics for crowd health management","volume":"2","author":"Baklola","year":"2024","journal-title":"Mass Gather. Med."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"100012","DOI":"10.1016\/j.mgmed.2025.100012","article-title":"Building climate-resilient infrastructure for Hajj pilgrims: A path to safer and sustainable pilgrimage","volume":"3","author":"Baklola","year":"2025","journal-title":"Mass Gather. Med."}],"container-title":["Vaccines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-393X\/13\/11\/1134\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,12]],"date-time":"2025-11-12T08:02:51Z","timestamp":1762934571000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-393X\/13\/11\/1134"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,3]]},"references-count":40,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2025,11]]}},"alternative-id":["vaccines13111134"],"URL":"https:\/\/doi.org\/10.3390\/vaccines13111134","relation":{},"ISSN":["2076-393X"],"issn-type":[{"value":"2076-393X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,3]]}}}