ACTIVE, LABORATORY-BASED SURVEILLANCE FOR DENGUE INFECTION IN BIEN HOA CITY IN 2002

This report described the program collaborated with the CDC Colorado USA with the name "Active, laboratory-based surveillance for dengue infection in Bien Hoa City in 2002". The result of this study is as follows: The predominant serotype which circulated in Bien Hoa City in 2002 was Dengue-4. The number of clinical diagnoses recorded as Viral Syndrome and Fever of Unknown Origin (899 cases) is higher than that diagnosed as DF/DHF (603 cases). The number of dengue isolates recovered from Viral Syndromes, Fever of Unknown Origins and Suspect Dengue Patients (48 viruses) was higher than that isolated from DF/DHF cases (45 viruses). This result demonstrated that Viral Syndromes and Fever of Unknown Origins had an important role which were reservoirs distributing dengue viruses into the population. In the past, Viral Syndromes and Fever of Unknown Origins were not the target for dengue control, so the dengue viruses from these patients continued to infect the mosquito vectors, thus the dengue outbreaks continued to develop. This data explains that all efforts to reduce morbidity and lethality caused by dengue in the recent years have never obtained hopeful results.