A twelve-year study of leptospirosis on Barbados

Between November 1979 and December 1991, 398 cases of severe leptospirosis were confirmed on Barbados (range for 1980–1991 23–56; mean 32.7; incidence 13.3/100,000/year). For the six-year periods 1980–1985 and 1986–1991 there was no significant change in incidence with time. Incidence is unlikely to change significantly in the next decade. Monthly average case numbers ranged from 1.4 (July) to 4.3 (November). The average (2.8) for June to December (the 7 wetter months) was not significantly higher than that (2.5) for January to May (the 5 drier months). The age range was 7–86. There were three times as many male cases (302) as female (96), and nearly 10 times as many in those <35. Although the highest number of cases (69) was in males aged 15–24, the highest incidence was in the older age groups, particularly the male 65–74 year-olds, and the female 55–64 year-olds. Leptospirosis was the proven cause of death in 55 (13.8%) hospital patients (annual range 0–13, mean 4.5). Some of a further 39 fatalities might have been cases. Death from leptospirosis was nearly twice as common among the women as among the men. Only one patient under 20 years of age died.Leptospira were isolated and identified from 117 (29.4%) of the 398 sick patients. The infecting organisms werebim (serogroup Autumnalis — 75),copenhageni (Icterohaemorrhagiae — 26),arborea (Ballum — 14) andbajan (Australis — 2). These infecting serovars could not be distinguished clinically, but infection was milder in children than in adults. Despite its predominance in surveyed children, serogroup Panama was virtually absent in this study. Rainfall is the major factor affecting the distribution of cases; not surprisingly, sanitation workers and agricultural workers appear to be the groups at highest risk. The general lack of clear-cut risk factors reflects the ubiquity of leptospires in the environment and the fact that the disease is not entirely occupational.     

The prevalence of severe leptospirosis among humans on Barbados

Leptospirosis was confirmed by the Leptospira Laboratory in 138 hospital patients on Barbados between early November 1979 and the end of 1982 (annual average 43.6 cases). These were the great majority of severe cases occurring on the island during that time. The crude incidence rate ranged between 15 and 23 per 100,000 population per year (average 17.6). 26 of the patients died (15 males, 11 females), giving an over-all case fatality rate of 18.8%, and an average of 8.2 deaths per year. 68% of all cases were in males. The highest percentages of cases were in males aged 20 to 24 and females aged 55 to 59, but the incidence of the disease in both sexes increased with age up to 60 years. Previous figures recorded on the island by the Ministry of Health for 1975-79 were considerably lower, with a mean of 23.6 cases per year and a crude annual incidence of 9.5 per 100,000. 15 of the patients died (13 males, 2 females), giving an over-all case fatality rate of 12.7% and an average of 3 deaths per year. 74% of all cases were in males. The highest percentages of cases were in the 20 to 29 and 50 to 59 year age groups for males and females, respectively, i.e., similar to those in the present series. In both sexes the incidence of leptospirosis increased with age up to 60 years.(ABSTRACT TRUNCATED AT 250 WORDS)     

The problem of human leptospirosis in Barbados.

The results of a retrospective study of human leptospirosis cases occurring in Barbados during the period 19-68-74, and of serological findings among high risk occupational groups, fever cases and health centre patients monitored for the disease during 1975-77, indicate that infection by serotype fort-bragg of the Autumnalis group is widespread in this Caribbean island. The occupational groups most affected are sanitation workers and sugar-cane workers. Results of serological tests conducted at the principle hospital are comparable with the results obtained by the microscopic agglutination reference test procedure conducted at the Pan American Zoonosis Centre (CEPANZO).     

Absence of epidemicity of severe leptospirosis in Barbados

The possibility of micro-epidemics of severe leptospirosis occurring on the island of Barbados was investigated by examining the space-time clustering of the disease in 212 laboratory-confirmed cases admitted to Queen Elizabeth Hospital, Bridgetown, over a 7-year period. A series of 109 patients with symptoms compatible with leptospirosis but shown to be otherwise by laboratory examination were also examined for comparison. No significant space-time clustering was found among the leptospirosis cases, indicating no evidence for micro-epidemics. By comparison, statistically significant clustering was apparent among the smaller non-leptospirosis series. Possible explanations for the absence of observed micro-epidemics of leptospirosis are discussed.     

Antigens recognized by the human immune response to severe leptospirosis in Barbados

Serum samples obtained from patients hospitalized in Barbados with severe leptospirosis were tested by the microscopic agglutination test (MAT), enzyme immunoassay (EIA) and immunoblotting with leptospires that had been isolated from these patients. While serum samples taken a few days after onset of symptoms often showed no apparent correlation between MAT and EIA, later sequential serum samples produced similar profiles in both tests during the course of infection. Immunoblotting sonicate from Leptospira interrogans serovars arborea, copenhageni and bim with patients' sera, revealed reactions with a number of bands that corresponded with outer envelope components. These components included lipopolysaccharide (LPS), flagella and other outer membrane proteins, in addition to a low-molecular-weight (MW) carbohydrate cross-reactive with members of the Leptospiraceae. IgM antibodies elicited in the first to second week after infection reacted mainly with LPS and the low-MW cross-reactive carbohydrate. Comparative analysis of isolates of the same serovar by sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting showed that while two serovar arborea isolates were identical, serovar bim isolates differed significantly from each other. This difference was also observed in comparative MAT testing.     

A cluster of leptospirosis among abattoir workers

In early December 1998, the Northern Rivers Public Health Unit (north-eastern New South Wales) was alerted to a possible cluster of leptospirosis cases by the supervising scientist of the Western Pacific Region World Health Organization/Food and Agricultural Organization Collaborating Centre for Reference and Research on Leptospirosis. Investigation revealed a cluster of eight leptospirosis cases diagnosed during October and November 1998. All were employees of a local meat works. Leptospira serovars isolated included pomona and hardjo. Symptoms included headache, fever, muscle pain, sore eyes, abdominal pain, vomiting, jaundice, and rash. Five of the eight cases were hospitalised. The infection could not be traced to any particular source. Unfortunately, records of stock killed during the exposure periods were not available. All cases reported exposure to large volumes of animal urine during the course of their work. Protective clothing provided included an apron, gloves, and rubber boots. All of the patients said they wore rubber boots and seven of the eight wore the apron provided. Only two patients reported wearing gloves, the remainder thought these were too difficult to work in.     

浙江省鼠形动物蜱源立克次体感染状况调查

目的了解浙江省不同类型地理环境中鼠形动物蜱源立克次体的感染状况。方法 2009—2011年在安吉县、金东区和天台县用夹夜法捕获鼠形动物,进行分类鉴定、无菌采集肝脾标本,并采用巢式PCR方法检测无形体属与埃立克体属16SrRNA以及立克次体属（包括斑疹伤寒群和斑点热群）与东方体属热休克蛋白基因groEL。结果 3个调查点共捕获鼠形动物14种851头,社鼠（30.32%）、黑线姬鼠（18.80%）和青毛鼠（11.75%）为主要优势种,其中金东区、安吉县和天台县的优势鼠种分别为社鼠（39.20%）、青毛鼠（32.05%）和黑线姬鼠（59.57%）。562份肝脾标本中检出立克次体48份,阳性检出率为8.54%;其中无形体属占3.38%,斑疹伤寒群占1.78%,恙虫病东方体属占1.78%,埃立克体属占1.07%,斑点热群占0.53%。金东区和安吉县无形体属检出率较高为4.76%和4.27%,斑点热群仅在天台县检出。社鼠的立克次体阳性检出率最高为14.97%。同一鼠形动物可存在多种立克次体混合感染。结论浙江省不同类型地理环境鼠形动物中广泛存在立克次体感染,不同地理位罝和不同鼠形动物的蜱源立克次体检出率不同。     

四川省钩端螺旋体宿主动物调查

目的：了解野鼠、耕牛和猪的钩端螺旋体带菌情况，探讨减少钩端螺旋体病发病影响因素。方法：对野鼠鼠肾、耕牛牛尿和生猪猪肾进行钩端螺旋体菌株的分离培养。结果：在野鼠鼠肾和水牛牛尿中分离出钩端螺旋体菌株。结论：野鼠仍是我省钩端螺旋体病的主要传染源，水牛为七日热群钩端螺旋体病的传染源。初步发现近年我省钩端螺旋体病发病减少可能是由于野鼠种群变化带来的结果。     

Poliomyelitis, rubella, and dengue antibody survey in Barbados. A follow-up study

A follow-up study of poliomyelitis, rubella, and dengue antibodies has been made in light of results obtained in a 1972 health and serological survey in Barbados, W.I. Poliomyelitis antibody neutralization tests performed on sera from 307 children under age 15 using overnight serum/virus mixtures on microtiter plates at low serum dilutions revealed the absence of polio antibody at 1:2 dilution in 13.7% for type 1, 6.5% for type 2, and 14.3% for type 3 virus. A significant correlation of the presence or absence of poliomyelitis antibody to types 2 and 3 was seen with the response to immunization histories. Forty-three of 49 girls (88%) given rubella vaccine (RA 27/3) in 1972 had demonstrable haemagglutination-inhibition antibody 4 years later. Neutralization tests for dengue antibody confirmed the results of the complement-fixation tests and indicated that type 2 was probably the sole infecting strain.     

Historical and current predictors of self-reported health status among elderly persons in Barbados.

OBJECTIVE: To understand the relative contribution of past events and of current experiences as determinants of health status among the elderly in the Caribbean nation of Barbados, in order to help develop timely public health interventions for that population. METHODS: The information for this prevalence study was collected in Barbados between December 1999 and June 2000 as part of the "SABE project," a multicenter survey in seven urban areas of Latin America and the Caribbean that evaluated determinants of health and well-being in elderly populations (persons 60 and older). We used ordinal logistic regression to model determinants of self-reported health status, and we assessed the relative contribution of historical socioeconomic indicators and of three current modifiable predictor groups (current socioeconomic indicators, lifestyle risk factors, and disease indicators), using simple measures of association and model fit. RESULTS: Historical determinants of health status accounted for 5.2% of the variation in reported health status, and this was reduced to 2.0% when mediating current experiences were considered. Current socioeconomic indicators accounted for 4.1% of the variation in reported health status, lifestyle risk factors for 7.1%, and current disease indicators for 33.5%. CONCLUSIONS: Past socioeconomic experience influenced self-reported health status in elderly Barbadians. Over half of this influence from past events was mediated through current socioeconomic, lifestyle, and disease experiences. Caring for the sick and reducing lifestyle risk factors should be important considerations in the support of the current elderly. In addition, ongoing programs for poverty reduction and increased access to health care and education should be considered as long-term strategies to improve the health of the future elderly.     

Stigma, discrimination, and HIV/AIDS knowledge among physicians in Barbados.

OBJECTIVE: To determine the extent of clinical knowledge of HIV/AIDS that physicians in Barbados have and their attitudes towards persons living with HIV/AIDS. METHODS: In 2000 the Barbados Association of Medical Practitioners conducted a survey in order to assess its members' views on HIV/AIDS issues. Over a two-month period 203 physicians (76% of all those practicing in the country) were interviewed. The survey included physicians working in private practice and the public sector. They were surveyed individually concerning their attitudes towards counseling as well as their clinical knowledge, perception of safe practices, fear of occupational exposure, views on ethical issues, experience treating HIV/AIDS patients, and background with HIV/AIDS continuing education. RESULTS: In comparison to physicians who had graduated in later years, physicians who had graduated in 1984 or earlier had seen fewer HIV/AIDS clients, had lower levels of knowledge about the disease, were more likely to test for HIV/AIDS without informed consent, and were less likely to have ever attended a continuing education training course on HIV/AIDS. Overall, knowledge of the clinical indications of HIV/AIDS was low, and 76% of the physicians did not think they had adequate counseling skills. Over 80% of the physicians were comfortable looking after HIV/AIDS patients. While 95% of the physicians would not release HIV test results without a patient's consent, 33% would test, without consent, a seriously ill patient, and 15% would test without consent a patient upon whom they had to perform an invasive procedure if they perceived the patient to be from a high-risk population such as gay men or commercial sex workers. Only 53% of the physicians had attended an HIV/AIDS in-service training program between 1995 and 1999. CONCLUSIONS: Physician training in Barbados should focus on all aspects of HIV/AIDS care, including clinical and emotional factors. Attendance at such training should be mandatory for public sector physicians, and medical school curricula need to be examined to ensure their HIV/AIDS content is current and comprehensive.     

Sero surveillance of leptospirosis among sewer workers in Pune

Leptospirosis is an important occupational disease affecting people coming in contact with animals and their discharges. The occurrence of infection in ones workplaces is linked to the environment to which the worker is exposed and the adaptability of the organism in that working environment. Rodents usually abound in underground sewers and are carriers of leptospira. The urine of rodents and other animals present in that area is likely to contaminate these sewers. Leptospira are excreted in the urine of infected animals. Thus sewer workers are at a potential risk of leptospirosis. The prevalence of leptospirosis in these workers could thus indirectly predict the presence of the disease in animals in a particular geographical niche. Total seventy-eight sewer workers from 5 different municipal wards in Pune were examined to find out the evidence of past infection with leptospira using microagglutination test (MAT). The prevalence rate was found to be 16.6%. The serovars to which antibodies were detected include autumnalis (38.4%), pyrogenes (23.0%), canicola (15.3%) and pomona (15.3%). Evidence of leptospiral infection was found to be maximum in sewer workers in the areas of the city that were infested with rodents and stray animals.     

A waterborne outbreak of leptospirosis among United States military personnel in Okinawa, Japan

A waterborne outbreak of leptospirosis occurred among US military personnel during September 1987, on the island of Okinawa, Japan. Micro-agglutination titres for leptospiral antigen of greater than or equal to 200 were detected in hospitalized adult males averaging 22.5 years of age with symptoms compatible with leptospirosis. Epidemiological findings revealed two case clusters distinguished by time and place of exposure. The overall attack rates among recreational swimmers and combat skills training participants were 467/1000 (7/15) and 183/1000 (15/82), respectively. Swallowing of water differentiated individuals with laboratory-confirmed infection from those with no infection, while water immersion alone did not appear to result in leptospiral infection. Additionally, subnormal rainfall may have contributed to the risk of exposure associated with this outbreak.     

Characteristics of HIV-infected childbearing women in Barbados.

OBJECTIVE: To describe the demographic profile, social and family characteristics, and lifestyle traits of HIV-infected childbearing women in the Caribbean nation of Barbados in comparison to a control group of HIV-negative women. METHODS: Data for this report were drawn from the Pediatrics HIV Surveillance Program of the Queen Elizabeth Hospital in Barbados. The data covered all HIV-infected women in the country who delivered between 1986-2000, with similar data coming from a control group of HIV-negative childbearing women. Routine information recorded during antenatal care was obtained from the women's case records. Additional data were collected from interviews with the women. RESULTS: There were 182 HIV-infected women who delivered during the study period, and a group of 202 childbearing women served as controls. In comparison to the control group, the HIV-infected women were younger, more often multiparous, and more likely to have been unemployed at the time of their pregnancy. The HIV-infected women also had had an earlier onset of sexual activity, had had more sexual partners during their lifetime, and were more likely to be involved with an older sexual partner. At the time of giving birth most of the HIV-infected women were asymptomatic for AIDS and were living with either their parents (mother or father or both) or the baby's father. In addition, at the time of their six-weeks-postnatal visit, the large majority of the HIV-infected women were involved in caring for their children. The proportion of HIV-infected women who were diagnosed prior to childbirth increased significantly over the study period, rising from 25% during 1986-1990 to 82% during 1996-2000. Slightly over one-fifth of the HIV-infected women had had one or more subsequent pregnancies after they had learned that they were infected. CONCLUSIONS: The early age of sexual activity as well as repeated pregnancies, especially from different and older partners, may have contributed significantly to both vertical and horizontal HIV transmission in Barbados. Future studies of HIV incidence and its trend among childbearing women could be important for monitoring the HIV epidemic in this country. Many of the HIV-infected childbearing women in our study were unemployed, sick, and had multiple children. Therefore, to help them to plan for and cope with the disease and also the care of their children beyond the perinatal period, there is a need to provide the women with repeated counseling with continued follow-up and, where necessary, additional economic, social, and medical support.