A pilot project to improve surveillance for dengue fever in three Caribbean islands - abstract

Simultaneous or sequential circulatin of dengue serotypes 1, 2 and 4 has been detected in several Caribbean countries. This may increase the chances of persons experiencing secondary infections with heterotypic dengue serotypes. Consequently there may be an increased risk of dengue haemorrhagic fever/dengue shock syndrome. Furthermore, Caribbean populations may not have been exposed to dengue serotype 3 in over 20 years and a large proportion of the population may not have immunity to this virus. Dengue type 3 has been recently isolated during epidemics in Central America and its introduction poses a further threat to the Caribbean. Sentinel surveillance was undertaken in a pilot study during August to December 1995 to improve the monitoring of Dengue serotypes on the islands of Jamaica, Trinidad and Dominica. Virological investigations were performed on a total of 92 patients who presented at designated community and hospital health care facilities on the 3 islands. Dengue virus types 1 and 2 were isolated from Jamaican patients. No dengue isolates were obtained from Dominica or Trinidad, although IgM capture ELISA test results suggested current or recent exposure to dengue virus in one Dominican patient. Improved surveillance for dengue could lead to detection of the emergence of new dengue serotypes, or detection of increased virus activity. Using surveillance data to target efforts to control the Aedes aegypti mosquito vector in areas where infection cases reside could reduce the impact of dengue disease in the Caribbean. (AU)

Comparative prevalence of parasites in five communities in Dominica - abstract

We analysed 640 randomly collected, fresh samples of faeces from children aged 2-10 years, living in five different communities in Dominica, by both the modified Kato and formol-ethyl acetate concentration techniques (FEA). There was excellent correlation (greater than 99.5 percent) for ova of Ascaris and Trichuris between the modified Kato techniuqe and the formol-ethyl acetate concentration technique. However, the FEA technique was able to provide information about a wider range of GI parasites. There was a high prevalence for ascariasis at Soufiers (77.8 percent) and Scott's Head (72.7 percent), an elevated prevalence at Grand Bay (28.1 percent), a significantly reduced prevalence at St. Joseph (10.4 percent) and a virtual absence of ascarisis from Mahaut (0.63 percent). Trichuriasis was also significantly higher in Soufriere (81.5 percent) and Scott's Head (85.2 percent), than in Grand Bay (33.7 percent), St. Joseph (34.9 percent), or Mahaut (27.2 percent). In the five communities surveyed, the infections with Ascaris lumbricoides and Trichuris trichiura were, generally, of low intensity (less than 5,000 epg). The higher prevalence of all parasites in the Soufriere and Scott's Head areas was probably due mainly to poorer sanitary conditions (AU)

Investigation of a typhoid outbreak on Dominica

Investigation of a typhoid fever epidemic in Dominica suggests the disease was spread largely by handlers of contaminated food. This and related findings underscore the need for better sanitation, periodic screening of food handlers for Salmonella typhi, and establishment of a special registry containing data on all cases of typhoid fever (AU)