Magnitude, distribution, and estimated level of underreporting of acute gastroenteritis in Jamaica.

Jamaica is the third largest island in the Caribbean. The epidemiology of acute gastroenteritis (AGE) is important to Jamaica, particularly in the areas of health, tourism, and because of the potential impact on the local workforce and the economy. Data collected by the National Surveillance Unit on the prevalence of AGE transmitted by food are not accurate. To determine the true magnitude, risk factors, and the extent of underreporting of AGE in Jamaica, we conducted a cross-sectional, population-based retrospective survey during the periods of 21 February-7 March and 14-27 June 2009, corresponding to high- and low-AGE season respectively. Of the total 1,920 persons selected randomly by a multistage cluster-sampling process, 1,264 responded (response rate 65.8%). Trained interviewers administered a standardized, validated questionnaire during face-to-face interviews. The overall prevalence of self-reported AGE was 4.0% (95% CI 2.9-5.1) at a rate of 0.5 episodes/per person-year. The highest monthly prevalence of AGE (14.6%) was found among the 1-4 year(s) age-group and the lowest (2.1%) among the 25-44 years age-group. Of the 18 cases (36%) who sought medical care, 11% were hospitalized, 33% were treated with antibiotics, and 66.7% received oral rehydration fluids. Only 2 cases who sought medical care reportedly submitted stool specimens. The mean duration of diarrhoea was 3.1 days, which resulted in a mean loss of 4 productive days, with over half of the cases requiring someone to care for them. The burden of syndromic AGE for 2009 was extrapolated to be 122,711 cases, showing an underreporting factor of 58.9. For every laboratory-confirmed AGE case, it was estimated that 383 more cases were occurring in the population. This research confirms that the prevalence of AGE is underreported in Jamaica and not being adequately detected by the current surveillance system. The components of the integrated surveillance system for AGE in Jamaica, particularly the laboratory aspect, need to be strengthened.

Success in controlling a major outbreak of malaria because of Plasmodium falciparum in Jamaica.

In 2006, after 44 years of eradication of malaria, Jamaica had an outbreak of Plasmodium falciparum: 406 confirmed cases between September 2006 and December 2009 with a peak of the epidemic in December 2006. In response to the outbreak, the Ministry of Health launched an emergency response through early detection and prompt treatment of cases, vector control, public education and intersectoral collaboration. Ninety percent (361) of cases were residents of Kingston, and 63.6% were identified through house to house surveillance visits. For 56% of the confirmed cases, treatment with chloroquine was initiated within a week of onset of symptoms. Only one (0.3%) of 358 cases who had a post-treatment smear on day 7 had a persistent asexual parasitaemia, while none of the 149 persons who had a follow-up smear on day 28 was positive. The outbreak highlighted the need for increased institutional capacity for surveillance, confirmation and treatment of malaria as well as effective prevention and control of outbreaks which can occur after elimination. Jamaica appears to have successfully eliminated malaria after its reintroduction.

The Jamaican hypertension prevalence study.

This study was designed to investigate the prevalence of hypertension in Jamaica. Jamaica has an area of 4,411 square miles and is divided into 14 parishes. The visited districts were randomly selected. The sample population was selected based upon a two-stage stratified random sampling design. Each dwelling in the "Sampling Universe" had an equal probability of being selected. The survey team spent a week in the districts in each parish selected. Employing the Statistical Institute of Jamaica's (STATIN) two-stage stratified random sampling design, preselected house-holds were visited. Non-response was documented and considered in the final analysis. Only individuals 15 years and older were allowed to participate in the study. The 2,064 subjects who participated were the basis for estimates of hypertension. Following logistic regression analysis, the main risk factors for hypertension are being female, advancing age, obesity, having diabetes and having a family history of hypertension. Jamaica has a point prevalence of hypertension of 30.8% in the 15-and-over age group. These findings would greatly assist in formulating policies to deal with this scourge of society.

Leptospirosis and malaria as causes of febrile illness during a dengue epidemic in Jamaica.

BACKGROUND: Epidemics of febrile illnesses are often associated with rainy seasons in the tropics. During 2007-2008 an epidemic of dengue was identified in Jamaica based on serological testing of sera. METHODS: A subset of 3165 of 5400 sera submitted for dengue analysis was tested for Leptospira IgM and malaria IgG using ELISA to determine their role in causing epidemic fever. FINDINGS: Seropositivity for dengue, leptospirosis, and malaria were 38·4 and 6·0 and 6·5%, respectively, indicative of three concurrent epidemics. Mixed exposure to all three diseases was rare (0·1%), as were mixed dengue/malaria (2·4%); dengue/leptospirosis (1·6%), and leptospirosis/malaria (0·03%) exposure. Exposure to dengue and malaria appeared to occur most frequently among children while leptospirosis was more common among adults. CONCLUSION: While serological diagnosis definitively established that dengue was the main cause of the epidemic febrile illness, the data suggested that there may be other causes of fever, which may occur simultaneously. Consequently, leptospirosis and malaria should be considered as causes of fever during epidemics of dengue in endemic areas.