Evaluation of Dengue Surveillance System of Nonghin Hospital, Loei Province, 2022–2024

Abstract

Background: Nong Hin District reported the second-highest dengue incidence rate in Loei Province. A sharp increase in dengue cases during 2023–2024 highlighted the need to evaluate the current dengue surveillance system. This study aimed to assess the reporting process, quantitative and qualitative attributes of the system, and provide recommendations for system improvement.

Methods: A cross-sectional descriptive study was conducted in dengue patients (including dengue fever, dengue hemorrhagic fever, and dengue shock syndrome) at Nonghin Hospital from January 1, 2022 to December 31, 2024. The cases were chosen by stratified random samplings by selected ICD-10 codes for dengue and related disease. The case definitions adapted from the Division of Epidemiology definitions, along with physician diagnosis and ICD-10 codes. The reports with codes 26, 27 and 66 in Digital Disease Surveillance were also reviewed. The disease reporting process was studied, and personnel involved in the surveillance system were interviewed.

Results: Nong Hin Hospital reported dengue cases daily via the DDS system. Nurses at service units were able to report directly to affiliated health promotion hospitals. System sensitivity based on case definition, physician diagnosis, and ICD-10 codes was 55.77%, 55.46%, and 55.66%, respectively. Using case definition, sensitivity during the epidemic season, off-season, among inpatients, and outpatients was 56.70%, 51.22%, 63.44%, and 50.86%, respectively. The positive predictive value (PPV) based on case definition was 100%. Data completeness and accuracy were 100% for all variables, except for the onset date, which was accurate in 70.79% of cases. Timeliness ranged from 94.74% to 100%. All surveillance variables were representative. Staff at all levels expressed satisfaction with the system. Reporting procedures were considered simple and convenient. Most administrators did not directly access the DDS but used surveillance reports for planning and analysis. Inpatient departments used the data to manage medical supply readiness during outbreak periods.

Recommendations: 1) Epidemiologists should coordinate with service units to standardize dengue reporting methods both during and outside the epidemic season. For outpatient departments with rotating staff, guidelines should be clearly communicated to new personnel. 2)Physician and staff involved in medical record keeping and ICD-10coding should be trained to ensure complete documentation of clinical symptoms, laboratory results, and patient addresses, with diagnoses accurately coded. 3)A system should be established for verifying patient data accuracy, tracking onset dates, monitoring lab results delayed over three days, issuing alerts for new results, and updating records following changes in diagnosis.