Dengue fever (DF) is a major public health concern in the Dominican Republic. In recent years, several epidemics of DF have been reported to the Pan American Health Office (PAHO), but the extent of the epidemics has not been clearly understood yet. Therefore, we conducted a nationwide seroepidemiology of dengue (DEN) infection. At the same time, we conducted an interview survey to assess public awareness regarding the disease. The serum samples were collected at seven main cities in the Dominican Republic and screened for DEN antibody with a commercial ELISA kit. A total of 2007 serum specimens were examined. The prevalence of DEN antibody in the seven cities varied between 43.1 and 89.7%. Neutralization (N) test carried out on the ELISA-positive serum from Samana, one of the high antibody-prevalent cities, revealed that all the sera showed positive to at least two DEN serotypes. Geometric mean N titers against DEN-1, 2, 3 and 4 were 40.5, 463.7, 59.9 and 454.4 respectively. No difference in antibody prevalence was observed between males and females. It appeared that a high level of awareness regarding DF did little affect DEN prevalence. Strong, concrete public health strategies that motivate the local community to combat DF are required.

OBJECTIVEThe aim of this survey was to compare the seroprevalences ofHelicobacter Pylori (H. pylori) and chronic atrophic gastritis (CAG) in Tanzania and the Dominican Republic, both of which are tropical countries, and thereafter compare the prevalences in Tanzania and the Dominican Republic with prevalences from our previous studies done in Japan (1991) and China (1996/97).

METHODSCommunity-based study in which 573 inhabitants of Tanzania and 1,215 inhabitants of the Dominican Republic answered detailed questionnaires on upper digestive tract diseases, and then underwent screening for gastric cancer by serum pepsinogen and testing for antibody toH. pylori.

RESULTSAfter adjusting to the 'Age-Standardized Rate' (ASR) using the world population in 1995, the seroprevalences ofH. pylori infection in male and female subjects for Tanzania (m=85.3% & f=88.2%) were very high compared to those for the Dominican Republic (m=63.5% & f=62.4%) and Japan (m=62.0% & f=46.8%), and similar to those of China (m=78.0% & f=77.3%). Also, the agestandardized prevalences of CAG in males and females for Tanzania (m-0.237& f=0.458). were higher than those of the Dominican Republic (m=0.168 & f=0.211) and China (m=0.111 & f=0.107) and compared well with those of Japan (m=0.266 & f=0.352).

CONCLUSIONSAlthough Tanzania and the Dominican Republic are both developing countries, Tanzania had a very high age-standardized prevalence ofH. pylori and CAG compared to that of the Dominican Republic, which showed a trend similar to that of Japan.