Scarlet Fever

Since 2004, the French syndromic surveillance system SurSaUD® coordinated by the French Public Health Agency (Sante publique France) daily collects morbidity data from two data sources: the emergency departments (ED) network Oscour® and the emergency general practitioners associations SOS Medecins. Almost 92% of the French ED attendances are recorded by the system. SOS Medecins network is a group of 62 associations of general practitioners, dispatched all over the territory. Sante publique France received data from 61 out of 62 associations. Both data sources collect medical diagnosis, using ICD10 codes in the ED network and specific medical thesaurus in SOS Medecins associations. These data are routinely analyzed to detect and follow-up various expected or unusual public health events all over the territory. The system is also used for reassurance of decision makers. In that framework, in March 2017, the French Ministry of Health requested Sante publique France to validate a potential scarlet fever outbreak in France.

Objective:

Describe a case study of validation of a scarlet fever outbreak using syndromic surveillance data sources.

Scarlet fever is a notifiable disease in Hong Kong for over 40 years. There was relatively low activity of scarlet fever until an outbreak in mid-2011 which resulted in two deaths and more than 1,500 cases. Scarlet fever incidence remained elevated since then with >10-fold increase comparing to that before the upsurge. Reemergence of scarlet fever was also reported in China in 2011 and the United Kingdom in 2014. We analyzed the patterns in scarlet fever incidence in Hong Kong using the notifiable disease surveillance data from 2005-2015.

Objective:

This study examined the epidemiology of scarlet fever in Hong Kong based on notifiable disease surveillance data, in a period where a 10-fold upsurge in scarlet fever incidence occurred. High risk groups and important factors associated with scarlet fever transmission were identified.