Epidemiological characteristics of dengue hemorrhagic fever in Ba Tri district, Ben Tre province, 2004 – 2014

Abstract

      Currently, dengue fever/dengue hemorrhagic fever (DF/DHF) has an upward trend and it is an important public health challenge in many areas, including Ba Tri District, Ben Tre Province. A cross sectional study was conducted in 2015 with a retrospective secondary data analysis on DF/DHF cases from 2004-2014 in Ba Tri District aimed to explore the epidemiological characteristics of the disease. The results showed that DF/DHF occurred mainly from May to August annually and peaked in June and July. During 2004-2014, there were a total of 5728 of DF/DHF cases, 5 deaths and the rates per 100,000 people ranged from 20.9 to 1018.5. The disease had occurred at 24/24 communes and town, especially in communes located near by the sea and rivers. 50.2% of cases were males and 49.8% cases were females. 87.9% of patienrs aged ≤ 15 years old and the rate of severe DHF was on a decreasing trend. Clinical clasification showed mainly DF and DHF with warning symptoms (83.2%). All four serotypes presented and there was a change in types of serotypes being responsible for epidemic each year. In 2014, DEN-1 was the main serotype detected (97.3%). 2004 and 2010 had the highest number of cases /100,000 people, which were 353.7 and 1018.5, and was also the years with mainly DEN-3 responsible for the epidemic. Aedes aegypti was the main vector for transmitting the disease. Common clinical symptoms included high fever (62.8%), headeach (44,7%), positive tourniquest test (44,2%), hemorrhagic manifestation (26.6%), and 53.8% patients had hrombocytopenia (platelet count of ≤100,000mm3). 95.5% DF/DHF patients were clasified as DF, 3% with warning symptoms and only 1.5% were severe DHF cases. 27,7% patients initially diagnosed with DF/DHF were re-confirmed as not having DF/DHF later on before they left the hospitals. Based on the results, the authors provided several specific recommendations regarding monitoring and controling of DF/DHF in the District.