Taipei's Use of a Multi-Channel Mass Risk Communication Program to Rapidly Reverse an Epidemic of Highly Communicable Disease

This article reports on a multi-channel crisis management mass communications programme that included, amongst other strategies, the sending of short message service (SMS), or text, messages to approximately 2.2 million Taipei City, Taiwan, residents. The messages were sent on October 12 2007 in the context of an outbreak of acute hemhorrhagic conjunctivitis (AHC), which is frequently accompanied by a highly transmissible acute eye infection. In short, the evaluation finds that the timely launch of this systematic, communication-based intervention proved effective at preventing a dangerous spike in AHC and was able to bring this high-risk disease under control.

This risk communication programme focused on communicating directly to the public through three routes: (1) schools delivered a Taipei Department of Health letter signed by the mayor (which detailed AHC information and prevention methods) for students to take home to their parents, (2) the mayor held a press conference to discuss the epidemic and offer guidance to citizens for preventing the spread of the disease, and (3) over 2.2 million SMS messages were delivered to all Taipei mobile phone numbers. The messages briefed Taipei residents on the current status of the epidemic and recommended citizen-level control measures. All communications suggested that symptomatic students stay at home, apart from other members of the family, and recommended household disinfection.

As detailed here, Taipei's ability to launch such a large-scale SMS campaign was a direct result of Taiwan's Communicable Disease Act (2006). This act allowed government officials to override the people's right to privacy when responding to epidemic disasters. In this case, the Taipei city government held a contract with Taiwan's six major mobile phone companies and committed all of them to allowing six free public service messages (per year) to be sent to their users if deemed necessary by the proper authorities.

The researchers analysed 461 reported AHC cases from 10 Taipei schools (totaling 18,134 students). For each of the schools, they randomly selected one class that had had occurrences of AHC - eye redness (pink eye) accompanied with pain, swelling, tearing, or discharge - and one class where there had been no occurrence of AHC as case and control groups, respectively. Family clusters were defined as two or more cases of AHC occurring in one family within 14 days; class clusters were defined as three or more AHC cases in one class of students within 7 days. Both family clusters and class clusters were charted through epidemiological investigation.

Median time from exposure to onset of the disease was 1 day. This was significantly shorter for cases occurring in family clusters than in class clusters (mean±SD: 2.6±3.2 vs. 4.39±4.82 days, p = 0.03), as well as for cases occurring in larger family clusters as opposed to smaller ones (1.2±1.7 days vs. 3.9±4.0 days, p<0.01). Taipei's programme was found to have had a significant impact on patient compliance. Home confinement of symptomatic children increased from 10% to 60% (p<0.05) and helped curb the spread of AHC. Taipei experienced a rapid decrease in AHC cases between the Friday of the SMS announcement and the following Monday, October 15 (0.70% vs. 0.36%). By October 26, AHC cases had reduced to 0.01%. The success of this risk communication programme in Taipei City (as compared to Keelung City, where an AHC outbreak had occurred the previous month) is further reflected through rapid improvements in three epidemic indicators: (1) significantly lower crude attack rates (1.95% vs. 14.92%, p<0.001), (2) a short epidemic period of AHC (13 vs. 34 days), and (3) a quick drop in risk level (1-2 weeks) in Taipei districts that border Keelung (the original domestic epicentre).

In the researchers' words: "We believe the SMS messaging component of the program was integral to the success of the 2007 AHC intervention and will continue to explore the use of this tool. We know from our questionnaire that fourteen percent of parents who confined their affected children at home during 2007's AHC outbreak reported that their decision to comply with this preventive measure was based on the SMS messages they received. Although the effects of the cell phone method cannot be fully isolated from the multi-channel risk communication system in this study, we believe that future interventions that utilize SMS exclusively will provide more insight on the effectiveness of this method."

They conclude by recommending that public health officials incorporate similar methods into existing guidelines for preventing pandemic influenza and other emerging infectious diseases.