Page 199 - Timeliness of Infectious Disease Notification & Response Systems - Corien Swaan

notification delay, physicians should provide prophylaxis to high risk contacts themselves directly after laboratory confirmation or in case of epidemiological linkage. It also underlines the need for primary prevention through vaccination. Prolonged disease identification delay for bacterial pathogens causing gas- tro-enteritis as shigellosis, STEC and (para)typhoid fevers is the result of patient, doctor and laboratory delay (14). Delays for these pathogens are described by studies in the UK, US, Korea and Australia as well and included recommenda- tions for limiting doctor, laboratory and notification delay (13, 16, 19-21). Our studies show that for STEC and shigellosis, the outbreak control timeframe or incubation period timeframe is probably beyond reach even with short notifi- cation delays as in the Netherlands. Insight in laboratory tests delay is there- fore necessary to evaluate the potential reduction in delay in this part of the notification chain. As with pertussis, if notifications are too late for the MHS for optimal outbreak control, primary prevention of these diseases among the population needs prioritization. It also emphasizes the necessity of other sur- veillance systems for early identification of clusters such as typing of foodborne pathogens as Salmonella. However, during an outbreak investigation, reduction of patient, physician and laboratory delays is still necessary for real-time moni- toring the effect of interventions.
We conclude that for some infectious diseases the total local reporting de- lay (D1) is far longer than the timeframe needed for outbreak control, or longer than two incubation periods. For these diseases, primary prevention through e.g. health education, vaccination, and food safety is important besides reduc- tion of the local identification time during outbreaks.
Research question 3: Which elements of notification systems facilitate timely notification?
We identified the following facilitating elements in notification systems: notifica- tions by laboratories either combined with physicians, legal frameworks for no- tification delay, training and provision of evaluation and feedback to reporters. Electronic notifications systems were only faster than conventional reporting in comparative studies. During outbreaks, alerts systems contribute to decreasing disease identification and notification delay through information and providing guidance on case definitions and available laboratory confirmation tests.
General discussion 197
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