Sustaining community event-based surveillance in Sierra Leone

ObjectiveTo assess whether the change in death swabbing policy in SierraLeon has begun to affect community death reporting, we analyzedtrends in death reporting before and after the policy change.IntroductionStemming from the 2014-6 Ebola virus disease (EVD) outbreak,community event based surveillance (CEBS) was implemented inSierra Leone using community health workers to generate alerts fortrigger events suggestive of EVD transmission. Through September30, 2015 (last month of active EVD transmission), the majority (86%)of alerts reflected community deaths; this was beneficial as Ebola-related deaths were detected with delay during the epidemic’s peak.The Government had implemented a policy of mandatory swabbingand testing of all dead bodies. The policy changed on June 30, 2016wherein only swabbing of deaths deemed to be high-risk for EVD isrequired. To assess whether this policy change has begun to affectcommunity death reporting, we analyzed trends in death reportingbefore and after the policy change.MethodsThis analysis was conducted using data from nine districts duringperiod 1 (January-June 2016) and period 2 (July 2016). Weeklychanges in the reporting of death alerts during the two periods wereassessed. An interrupted time series analysis (ITS) with a segmentedlinear regression was also used to assess the immediate impact of thepolicy change.ResultsDuring period 1, monthly changes in death alerts across districtswere variable (-8% to 16%). Comparison of the weekly averagebetween periods 1 and 2 showed a 33% reduction in death alerts.During period 1 (before the policy change), there was an overallsignificant increase of 3.2 death alerts per week (p=0.00) andno immediate impact or changes in the trend afterwards. At thedistrict level, on average 354 death alerts were generated weekly inJune, compared to 237 in July (33% reduction); Moyamba districtexperienced the largest drop in death alerts from 46 to 16 (65%).ConclusionsCommunity death reporting provides early warning of EVDtransmission by rapidly capturing death alerts where vital registrationis not fully functional. Although we have one month of data post-policy change, this preliminary analysis suggests that the changein swabbing policy may have halted an observed increase in deathreporting. Further community mobilization efforts and training arewarranted to prevent a drop in death reporting