In the summer of 2009, during the first months of the 2009 influenza pandemic, we launched a community study on influenza-like illness (ILI) in Ho Chi Minh City. About a dozen private clinics were enrolled initially, and they sent us daily reports on influenza-like illness cases by standard mobile phone SMS text messages. The study was designed for quick reporting and easy adoption. Every day, the enrolled clinics sent a single text message with the information below
and the simplicity of this design allowed us to enroll more clinics and build a long-term consistent time series of influenza-like illness trends in Ho Chi Minh City. We have enrolled 70 clinics throughout the course of the study, and 26 of these are long-term consistent reporters. The median clinic sees 28 outpatients per day (IQR: 15-50), and approximately 11% of patients meet the ILI case definition. The exterior of a typical clinic is shown below.
This is a single-doctor clinic that is open in the afternoons, and the doctor sees between 20 and 25 patients per day in a simple consultation room with just a desk and some chairs.
The key trend we follow is the percentage of patients in a clinic that meet the case definition for influenza-like illness (we use the ECDC case definition). The graph below shows this trend relative to its median.
When the line touches +5%, that means that approximately 16% of clinic patients meet the ILI case definition.
The big news this summer is that we launched a desktop and mobile website that reports these trends in real time. These can be viewed at www.ili.vn, in both English and Vietnamese. The website shows the past ten days of ILI activity, along with the previous ten days and the ten days before that for comparison. On your phone, the website should look like the screenshot below.
Thanks to Ha Minh Lam for all his hard work on the website.