Prevalence of malaria, dengue, and typhoid fever among children presenting with acute undifferentiated febrile illness (AUFI) landing at the emergency department of the National Institute of Child Health, Karachi

Objective: To determine the prevalence of malaria, dengue and typhoid fever among children presenting with acute undifferentiated febrile illness. Method: The descriptive, cross-sectional study was conducted from September 2022 to February 2023 at the emergency department of the National Institute of Child Health, Karachi, and comprised children aged <14 years with fever of unknown cause over the preceding 3-15 days. Whole blood samples were used for malaria slides and malarial parasite immunochromatographic tests. The serum was subjected to dengue non-structural antigen 1, immunoglobulin M and immunoglobulin G rapid diagnostic tests. Typhoid was diagnosed via blood culture. Antimicrobial susceptibility testing was also performed. Data was analysed using SPSS 22. Results: There were 290 patients with mean age 6.08±3.32 years. Out of 290,156(54%) were male while 134(46%) were female. Typhoid fever was identified in 25(8.8%) cases, followed by malaria 11(3.8%) and dengue 4(1.2%). The majority of patients 260(86.2%) had no confirmed diagnosis for these infections. No co-infections were identified. 19 out of 25 (75%) Salmonella typhi isolates demonstrated resistance to quinolones and while 18 out of 25 (73%) were resistant to third-generation cephalosporins, while all the isolates 25(100%) were sensitive to macrolides and carbapenems. No statistically significant associations were observed between demographic variables and infection status (p>0.05). Conclusion: Typhoid fever was the most frequently identified infection among the three causes of acute undifferentiated febrile illness. However, most cases remained undiagnosed, indicating the need for broader diagnostic evaluation.