High Rate of Recent Infections among International Travelers who bound for Australian Cities from Suvarnabhumi Airport, Thailand, November – December 2007

Abstract

Background: In 2006, over half a million of travelers departed from Thailand to Australia. Concern of upcoming influenza pandemic posed a challenge for public health professionals to find effective measures for delaying a global spread. We conducted a study to determine potential risk of transmission and factors related to the potential spread of infection across international border.
Methods: During November-December 2007, 188 travelers aged over 18 years departing from Thailand to Australia were randomly selected at Suvarnabhumi Airport in Samut Prakarn Province. A self-administered questionnaire was used for collecting data on demographics, travel patterns, diseases status and risk of acquiring infection.
Results: Of 114 surveyed, 74 (64.9%) entered Thailand for holidays. Majority of travelers (65.8%) spent less than 2 weeks in Thailand. Over half of them (55.3%) were males and mean age was 37.0 years (SD 13.9). Common illnesses in the past 2 weeks reported were URI (34.5%, 38/110) and diarrhea (12.7%, 14/110). For URI, 75.8% perceived that having coughing/ sneezing was a risk factor. Half of the travelers believed that consumption of contaminated food and water was a possible cause of diarrhea. About 39.5% (45/114) were never vaccinated against influenza. Regarding to the places visited, transportation used and events attended, only history of visiting farm in the past two weeks increased risk of having URI (Adjusted OR=4.64, 95% CI=1.01-21.20). In addition, staying at guest house (Adjusted OR=5.95, 95% CI=1.80-19.66) and staying at hotel more than 5 days per trip (Adjusted OR=20.48, 95% CI=1.26-333.08) were independent risk of diarrheal infection among travelers.
Conclusion: Nearly half of all travelers departing Thailand for Australia reported infections within 2 weeks of departure. URI was common among people who have recently visited a farm. Our findings suggested that improving surveillance and measures for international travelers was in urgent need to timely control the deadly respiratory infections, including SARS and novel influenza viruses.