Seasonal variation and co-infection of dengue and typhoid cases in a tertiary care hospital: A cross-sectional analytical study
DOI:
https://doi.org/10.61529/idjp.v35i1.492Abstract
Background: In tropical areas of Pakistan, dengue and typhoid fever are the most common causes of acute undifferentiated febrile illness. Their similar clinical characteristics make diagnosis and treatment much more difficult. The aim of this study is to determine the seasonal distribution and quantity of co-infection between laboratory-confirmed cases of typhoid and dengue among hospitalized patients in tertiary care hospitals.
Material and Methods: This cross-sectional analytical study was carried out at Quaid-e-Azam Medical College/ Bahawal Victoria Hospital Bahawalpur between January 2023 and December 2024. A total of 280 febrile patients with laboratory testing for both disorders and a fever (≥38°C for ≤10 days) were included. Typhoid was confirmed by blood culture for Salmonella typhi/ paratyphi, while dengue was confirmed by NS1 antigen detection. SPSS version 23.0 was used to evaluate data on demographics, clinical characteristics, and admission dates (classified into seasonal periods).
Results: 112 (40.0%) of the 280 patients had dengue, 94 (33.6%) had typhoid, and 9 (3.2%) had two infections. Typhoid surged after the monsoon (October-November 61.7% of cases), but dengue peaked during the monsoon (July-September 78.6%). In September and October, seven out of nine dual instances took place. The only significant predictor of dual infection was admission after the monsoon (adjusted OR = 5.2, 95% CI: 1.4-19.3; p=0.014).
Conclusion: There is a significant seasonal co-infection of dengue and typhoid during the post-monsoon transition, making integrated diagnostic and public health efforts necessary during this high-risk time.
Keywords: Dengue; Febrile illness, Salmonella typhi, Seasonal variation, Typhoid fever
References
Deng J, Wang L, Liu Y, Zhang X, Chen H, Li M, et al. Global, regional, and national burden of dengue infection in children and adolescents: An analysis of the Global Burden of Disease Study 2021. EClinicalMedicine. 2024; 78. DOI: https://doi.org/10.1016/j.eclinm.2024.102943
Murthy S, Date K, Patel H, Kambhampati AK, Buckeridge D, Luby SP, et al. Global typhoid fever incidence: an updated systematic review with meta-analysis. Lancet Infect Dis. 2025; 25(12): 1347-62.
DOI: https://doi.org/10.1016/s1473-3099(25)00359-7
Murthy S, Hagedoorn NN, Faigan S, Rathan MD, Marchello CS, Crump JA. Complications and mortality of typhoid fever: an updated global systematic review and meta-analysis. Lancet Infect Dis. 2026; 26(3): 270-3. DOI: https://doi.org/10.1016/s1473-3099(25)00551-1
Kuehn R, Baker S, Crump JA, Wain J, Parry CM, Dougan G. Enteric (typhoid and paratyphoid) fever. Lancet. 2025; 406(10509): 1283–94. DOI: https://doi.org/10.1016/s0140-6736(25)01335-2
Kumar K, Singh A, Sharma P, Gupta R, Chaudhary S, Yadav S. Acute febrile illness: A systematic review of infectious aetiologies among patients. J Pharm Negat Results. 2022; 13: 5079–93. Available from: https://www.pnrjournal.com/index.php/home/article/view/9473
Grundy BS, Houpt ER. Opportunities and challenges to accurate diagnosis and management of acute febrile illness in adults and adolescents: A review. Acta Trop. 2022; 227: 106286. DOI: https://doi.org/10.1016/j.actatropica.2021.106286
Ashton PM, Wong VK, Dongol S, Tran-Dien A, Thanh Duy P, Karkey A, et al. Interplay between the gut microbiome and typhoid fever: Insights from endemic countries and a controlled human infection model. Microbiome. 2025; 13(1): 168. DOI: https://doi.org/10.1186/s40168-025-02125-7
Dias RA. Towards a comprehensive definition of pandemics and strategies for prevention: A historical review and future perspectives. Microorganisms. 2024 Aug 30;12(9):1802. DOI: https://doi.org/10.3390/microorganisms12091802
Carey ME, Weill FX, Parkhill J, Holt KE, Dougan G, Baker S, et al. Global diversity and antimicrobial resistance of typhoid fever pathogens: Insights from a meta-analysis of 13,000 Salmonella Typhi genomes. Elife. 2023; 12: e85867.
DOI: https://doi.org/10.7554/eLife.85867
Liu G, Li Y, Zhang Q, Chen X, Wang J, Zhao Y, et al. The global burden of typhoid and paratyphoid fever from 1990 to 2021 and the impact on prevention and control. BMC Infect Dis. 2025; 25(1): 919. DOI: https://doi.org/10.1186/s12879-025-11223-8
Huy BV, Toan NV. Prognostic indicators associated with progresses of severe dengue. PLoS One. 2022; 17(1): e0262096. DOI: https://doi.org/10.1371/journal.pone.0262096
Thirumoorthy TP, Rajendran V, Senthilkumar B, Krishnan P, Ramachandran VG, Venkatesan M, et al. Recent emergence of cephalosporin-resistant Salmonella Typhi in India due to the endemic clone acquiring IncFIB (K) plasmid encoding bla CTX-M-15 gene. Microbiol Spectr. 2025; 13(5): e00875-24. DOI: https://doi.org/10.1128/spectrum.00875-24
Chandna A, Chheng K, Dittrich S, Faiz MA, Ghose A, Haque U, et al. Defining the burden of febrile illness in rural South and Southeast Asia: an open letter to announce the launch of the Rural Febrile Illness project. Wellcome Open Res. 2022; 6: 64. DOI: https://doi.org/10.12688/wellcomeopenres.16393.2
Vimal S, Vishwanathan V, Dharwadker A. Dengue and typhoid co-infection study. JMPAS J Med Pharm Allied Sci. 2022; 11(2347): 4542–6. DOI: https://doi.org/10.55522/jmpas.V11I2.2347
Iftikhar M, Naeem U, Khan S, Shah SAA, Khan MA, Qureshi MS, et al. Malaria and dengue co-infection: A comprehensive study in Peshawar, Pakistan. Cureus. 2024; 16(12): e76401. DOI: https://doi.org/10.7759/cureus.76401
Salh GK, Kaur J, Kaur H, Kaur P, Kaur R, Kaur G. Clinical profile of fever in patients admitted through the outpatient department in a North Indian tertiary care teaching hospital. J Clin Sci Res. 2021;10(4): 227–32. DOI: https://doi.org/10.4103/jcsr.jcsr_18_21
Soria MA, Cervantes SA, Siemer AB. Calmodulin binds the N-terminus of the functional amyloid Orb2A inhibiting fibril formation. PLoS One. 2022; 17(1): e0259872. DOI: https://doi.org/10.1371/journal.pone.0259872
Di Napoli M, Di Gregorio F, Di Natale M, Gialanella G, Esposito V, Pedone C, et al. Study of the antimicrobial activity of the human peptide SQQ30 against pathogenic bacteria. Antibiotics (Basel). 2024; 13(2): 145. DOI: https://doi.org/10.3390/antibiotics13020145
Baig A, Baig F, Khan MQ, Khan N. Epidemiological trend of dengue: A 2023 report from district Nowshera, Pakistan. J Health Wellness Community Res. 2025: e148. DOI: https://doi.org/10.61919/twr1sa06
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