Early Warning System for CD Dr Venanzio Vella, Senior Epidemiologist, CEEN

Objective of EWS for CD Early detection of outbreaks; Timely outbreak response and control; Monitoring trends; Evaluate impact of control activities.

patients GPs etc Private & public hospitals, clinics, etc As soon as a health worker see a patient with symptoms matching the case definition of diseases X, Y. Z tally the case on a weekly form 52 weekly reports per year per health unit are aggregated at intermediate level Feedbacks Feedback The central level aggregates the aggregates of the intermediate level Feedback LAB How the EWS should work Outbreak control

But there are problematic data

patients GPs etc Private & public hospitals, clinics, etc Some health worker stop reporting all cases and the decision of what and when to report becomes subjective. 50% of expected weekly reports are sent to the intermediate level in certain periods of the year, 100% in other periods No Feedbacks Feedbacks No Feedback The central level has difficulties in deciding is an increase in aggregate numbers is real of due to vagaries of reporting Feedback LAB can only detect a few diseases Not all epidemics are investigated Reasons for the problematic data

Basic Principles Guidelines on standardized data collection; Legislative Framework; Training to fill skill gaps; Quality control of data and feedback; Timely Monitoring to identify, investigate and control outbreaks; Evaluation of results.

Web Portal Software upgrading to include the data on CDs; Update of the indicators collected by the previous health project; Availability of statistical reports and other relevant documents; Training on using the portal.

Guidelines & Training Assessment against guidelines; Gaps in procedures, skills, resources; Training to fill gaps;

Standardization Standard List of Diseases; Standard Case Definition; Standard way of reporting; Behavioural practices of reporting (incentive, feedbacks, enforcement of legal obligations);

Quality control of data Completeness of weekly reports; Timeliness of weekly reports; Trend analysis; Outliers spotting; Feedback to periphery to confirm, justify, correct, incentivise.

Timely Monitoring to assess change Quality control to avoid vagaries of reporting; Threshold levels -Fixed values e.g. One case of Cholera, Polio, Measles is sufficient to issue an outbreak alert (likelihood of individual cases resulting in an outbreak), haemorrhagic fevers (severity of the disease); -Values exceeding expected trends

Speedy confirmation of outbreaks Laboratory capacity; Training; Human & other resources; costs.

Speedy investigation & control Field Epidemiology Training; Identification of Source; Tracing and testing contacts; Lab confirmation; Management and containment of spread of outbreaks; Quarantine control; Logistics and supplies; Coordinated multisectoral action; Communication.

Evaluate If EWS is complying with criteria -Timeliness (e.g. X% units reporting on time); - Completeness (e.g. X% expected reports received); - Feedback (e.g. X% GPs receiving feedback); If action is taken (e.g. % events investigated) If action taken has it been effective.