Risk factors associated with dengue fever outbreak in Harf Sufyan district-Amran governorate, Yemen, 2023: case control study

Dengue Fever (DF) is endemic in Yemen. On September 4th, 2023, the surveillance officer in Amran governorate reported an increased number of suspected DF in Harf-Sufyan district. On September 5th, 2023, a team from electronic Integrated Disease Early Warning System eIDEWS and Rapid Response (RR) program was sent to investigate. This study aimed to confirm the existence of the outbreak, determine risk factors, and recommend control measures. A descriptive case-control study (1:2 ratio) was conducted in Harf Sufyan from 5 September to 29 October 2023. The standard WHO case definition of DF was used to collect data from cases. Controls are any person living in the same area and his/her houses adjacent to the homes of cases without dengue fever. Data on individual, environmental, and behavioral risk factors were collected. Attack rates, odds ratios, and confidence intervals (CI) were calculated with p < 0.05 considered statistically significant. A total of 34 patients were positive for DF IgM, and 68 controls were included in this study. The males were 58% and 43% were < 30 years old of age. The overall attack rate was 0.9/100 of the population. The first case of DF was in the epi week 37 and reached the peak in week 39. Multivariate analysis revealed only wearing short (OR: 17, CI: 4.8–60.1) and T-shirts clothes and who working (OR: 23, CI: 2.9–33.2) were significant associated factors with DF infection. The findings highlight that the DF is emerging to be an important disease in in Harf Sufyan district-Amran governorate, Yemen. Occupational exposure and wearing short-sleeved clothing found to be the primary significant risk factors. Therefore, increasing community awareness about the DF infection, mode of transmission, and control measures, as well as protective clothes, is highly recommended. Not applicable.