Page 40 - Timeliness of Infectious Disease Notification & Response Systems - Corien Swaan

38 Chapter 2
Timeliness might also be influenced by the method of reporting. Traditionally, physicians used paper “report cards” provided by the Inspectorate of Health- care as a postal notification form, but these are little used nowadays. A minority of laboratories and physicians use electronic(e)-mail for reporting to the MHS; the precise proportion is unknown.
In this study we performed a quantitative analysis of the timeliness of in- fectious disease reporting in the Netherlands for six diseases. The intervals be- tween onset of symptoms and MHS notification, and between laboratory diag- nosis and notification, were used as quantitative measures of timeliness. These intervals can be influenced in different ways. Public health authorities can raise alertness of patients and physicians with regards to certain diseases so that laboratory tests are requested at an early stage. After laboratory confirmation of diagnoses reporting is most influenced by delays in communication. Such de- lays should be avoided, and so this interval is separately analysed in our study.
We report here serious reporting delays per disease, expressed in the per- centage of notifications occurring within one and two incubation periods.
We relate timeliness to the existence of physician-laboratory-MHS agree- ments, different methods of reporting (post, fax, telephone, e-mail), and the number of notifications using “report cards.”
Methods
We selected notifiable infectious diseases based on their epidemic potential, number of reported cases, use of laboratory confirmation, and available lit- erature for comparisons. As a result, reports for six infectious diseases were studied: shigellosis, entero-haemorrhagic or Shiga-like toxin-producing E. coli (EHEC/STEC) infection, typhoid fever, measles, meningococcosis, and hepatitis A virus (HAV) infection. The criteria for reporting these infectious diseases in the Netherlands are the clinical criteria in combination with the confirmation of the diagnosis by laboratory testing. Notifications from June 2003 to December 2008 were retrieved from the Dutch national database, including date of symp- tom onset, date of laboratory-confirmed diagnosis, and date of reporting to the Municipal Health Service (MHS).
For each case, we determined the intervals between the zero timepoint of symptom onset (T0) and MHS notification (T5), and between laboratory diag- nosis (T2) and MHS notification (T5). As shown in Figure 1, the interval between timepoints onset (T0) and notification (T5) was defined as the period from onset