Effect of Supervision or Short Messages (SMS) on the Detection Rate of Diseases Under Surveillance in the Littoral Region of Cameroon: A Randomized Controlled Health Facility-Based Trial.

INTRODUCTION: The Integrated Disease Surveillance and Response (IDSR) strategy was adopted in Cameroon in the early 2000s. However, some limitations in terms of the detection rates of diseases under surveillance are still observed. The present study was conducted to assess the effect of supervision or Short Message Service (SMS) reminders on the detection rate of cholera and measles in health facilities in Douala. METHODS: This was a randomised controlled health facility-based trial that involved assigning health facilities to either monthly supervision of personnel in charge of surveillance, SMS reminders, or a control group. The effect of the interventions was assessed by comparing the detection rates of cholera and measles by personnel with respect to the number of expected suspected cases in consultation records. RESULTS: A total of 271 health facilities were assessed for eligibility and 159 were included in the trial (53 per study group). The health facilities were assigned to either supervision, SMS or control group using stratified randomisation by health district. The detection rates of suspected cholera and measles cases were 11.05% and 35.19% in the control group, respectively. Health facilities in the supervision group demonstrated significantly higher detection rates of cholera cases [IRR (Incidence Rate Ratio) =1.87 (1.09-3.19); p = 0.022] and measles cases [IRR=1.78 (1.01-3.15); p=0.046], while there was no detected difference in the SMS group compared to the control group for both cholera and measles. The combined detection rate of both cholera and measles was significantly higher in the supervision group than in the control group; however, exposure to SMS did not produce a significant effect. After adjustment, results were consistent, except for detection of cholera cases, where the effect of supervision was attenuated and no longer statistically significant (adjusted IRR=1.39 (0.80-2.42); p=0.243). CONCLUSION: Supervision significantly improved the detection of suspected cholera and measles cases, whereas SMS reminders showed no significant effect. Strengthening routine supportive supervision should be prioritised to improve IDSR performance.