Page 45 - Timeliness of Infectious Disease Notification & Response Systems - Corien Swaan

Timeliness of infectious disease reporting, the Netherlands, 2003-2009 43
In contrast, given the long incubation period of HAV infections, only 2.8% of cas- es of HAV infection were not reported within two incubation periods. However, having corrected for the period of infectiousness before disease onset (Ic), the percentage of HAV infection notifications within one and two incubation peri- ods was substantially lower, with 71.4% of cases reported within one Ic (Table 2). Likewise for measles cases, the percentage reported within one Ic was lower (48.5%) than reported within one incubation period (67.2%).
For all six diseases, the median distribution of the period from diagnosis until notification (Pd) was between zero and three days, but a substantial per- centage of notifications occurred more than three days after diagnosis, varying between 12% for meningococcosis and 42% for shigellosis. Assuming a Pd of zero (i.e. MHS notification on the same day as laboratory diagnosis), the median Po decreased by one day for meningococcosis and HAV infection to as much as four days for shigellosis, EHEC/STEC infection, and typhoid fever (underlined figures in italics in Table 1).
For meningococcosis, the percentage of notifications occurring within one incubation period would be 14% higher if notification were to take place on the day of laboratory diagnosis. For shigellosis and EHEC/STEC infections, the improvement was likewise substantial (5.5% and 8.3% within one incubation period and 10% and 19.4% within two incubation periods). However, the overall percentage of cases reported within one incubation period remained low, at 5.9% and 10.6%, respectively.
Time trends
For shigellosis and HAV infection, the mean Pd decreased by one day from 2003 and 2004 to 2008, the period of our study. For HAV infection this decrease is not statistically significant. The mean Po for shigellosis and HAV infections how- ever, showed no clear time-trend over the years (Table 3).
Notification procedures
All 31 MHS in the Netherlands returned the questionnaire. Of these, 25 MHS had agreements with physicians to authorise direct laboratory reporting by one or more laboratories in their region. With regards methods of reporting by physicians and laboratories, five MHS received most reports by post, and 12 MHS received them largely by fax. Others reported a combination of these two methods, with telephone sometimes used in case of urgency; seven MHS received most laboratory reports by e-mail. For all the MHS, reports from physi- cians came most often by post or by telephone and rarely by e-mail.
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