An epidemiological study of A. cantonensis in Jamaica subsequent to an outbreak of human cases of eosinophilic meningitis in 2000.

The infection status of angiostrongylosis in Jamaica was assessed in wild rats and molluscs in the 5 years following the major outbreak of eosinophilic meningitis (EM) in 2000. Parasitological analyses of 297 Rattus rattus and 140 Rattus norvegicus, and 777 terrestrial molluscs from all 14 Parishes on the island revealed Angiostrongylus cantonensis in 32·0% of the rats and in 12·5% of the molluscs. Multivariate analyses confirmed that A. cantonensis occurred significantly more frequently in R. rattus (Odds Ratio [OR] = 1·76), while mean infection intensity in R. rattus was also significantly higher (16·8) than R. norvegicus (11·3) (Mann-Whitney U-test: P = 0·01). Third-stage larvae of A. cantonensis were detected in 29% of 86 Pleurodonte spp.; in 20% of five Poteria spp.; in 18·7% of 369 Thelidomus asper; in 11% of 18 Sagda spp.; and in 6% of 24 veronicellid slugs. Most rodent infections occurred in Northeastern Jamaica (OR = 11·66), a region where infected molluscs were also abundant. Given the prevalence of A. cantonensis infection in rats has significantly increased since the 2000 outbreak, and that a survey of human infections revealed at least ten autochthonous cases in the last 15 years, angiostrongylosis persists as an important zoonosis in Jamaica.

Balamuthia mandrillaris therapeutic mud bath in Jamaica.

Balamuthia mandrillaris is an emerging cause of encephalitis in humans. The transmission dynamics are poorly understood due to the high fatality rate and the sporadic nature of cases. Seventy-two soil samples were collected from beaches and the banks of lagoons, rivers, ponds, mineral springs and streams from across Jamaica and assayed for the presence of B. mandrillaris. Seventy-nine sites were sampled and the mitochondrial 16S rDNA gene of B. mandrillaris was amplified and sequenced to confirm the presence of the amoeba. One isolate of B. mandrillaris was recovered from soil from mineral spring which hosts an informal therapeutic mud bath business. Although B. mandrillaris is less frequently isolated from soil than other free-living amoebae, rubbing mud containing the organism onto the skin increases the likelihood of exposure and infection. This first report on the isolation of B. mandrillaris in the Caribbean and its presence in soil where human contact is likely warrants further investigation using serological methods to elucidate exposure patterns.

The antimicrobial screening of a Barbadian medicinal plant with indications for use in the treatment of diabetic wound infections.

OBJECTIVE: Diabetes mellitus is a chronic non-communicable disease with high prevalence in the North American and Caribbean region. Diabetic Foot Syndrome which is an associated complication can lead to the development of wounds and ulcers which can become infected. Justicia secunda, a plant known locally in Barbados as Bloodroot used in folklore for wound healing, was selected to test its ability to aid diabetic wound healing by antimicrobial activity. It was therefore tested against the bacteria Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, and Enterococcus feacalis (clincal strain) which are commonly found in diabetic wounds. METHODS: The plant was collected by local users. Methanol and acetone extracts of the plant were prepared with use of soxhlet extraction. The antimicrobial activity was assessed with the use of a modified Kirby-Baurer method. Concentrations of 200 mg/ml, 100 mg/ml, 10 mg/ml, and 1 mg/ml of the extract were used, with a standard ciprofloxacin 5 microg positive control, and a 5% dimethyl sulfoxide (DMSO) solution negative control. RESULTS: The J secunda methanol and acetone extracts with an extraction yield of 15.3% and 0.75%, respectively yielded no activity within the concentration range against the three strains of bacteria tested. In comparison with the positive control, relative inhibition zone diameter (RIZD) values of 0% resulted for both the negative control and the extracts, with the positive control having a value of 100%. CONCLUSION: The in vitro screen of the extracts prepared from J secunda, yielded no antimicrobial activity against the three strains of bacteria tested and therefore does not support the folklore claims by this mechanism of action.

An assessment of the process of informed consent at the University Hospital of the West Indies.

OBJECTIVE: To assess the adequacy of the process of informed consent for surgical patients at the University Hospital of the West Indies. METHOD: The study is a prospective, cross-sectional, descriptive study. 210 patients at the University Hospital of the West Indies were interviewed using a standardised investigator-administered questionnaire, developed by the authors, after obtaining witnessed, informed consent for participation in the study. Data were analysed using SPSS V.12 for Windows. RESULTS: Of the patients, 39.4% were male. Of the surgical procedures, 68.6% were scheduled, 7.6% urgent and 23.8% emergency, 35.2% were minor and 64.8% major. Information imparted/received was acceptable in 40% of cases, good in 24% and inadequate (unacceptable) in 36% of cases. Almost all (97.6%) patients stated that they understood why an operation was planned and 93.3% thought that they had given informed consent. Most (95.2%) thought that they had free choice and made up their own mind. A quarter (25.2%) of all patients were told that it was mandatory for them to sign the form. There was a discussion of possible side effects and complications in 56.7% of patients. CONCLUSIONS: This study clearly indicates that surgical patients at the University Hospital of the West Indies feel that they have given informed consent. However, it also suggests that more information should be given to patients for consent to be truly informed.

Absence of opportunistic parasitic infestations in children living with HIV/AIDS in children's homes in Jamaica: pilot investigations.

BACKGROUND: Many children living with HIV/AIDS in developing countries are infected with intestinal parasites. These infections add unnecessary morbidity to children already suffering the clinical insult of living with HIV/AIDS. OBJECTIVE: To determine the prevalence and potential risk factors for intestinal parasitic infections in HIV-infected children living in two institutions in Jamaica. METHODS: A total of 82 faecal specimens were collected from 41 HIV-infected children (age range 2-14 years) who resided in two Children's Homes. A structured 42-item questionnaire was administered to caregivers to obtain clinical and demographic data on each child. Faecal specimens from each patient were examined using standard microbiological techniques and Cryptosporidium antigen detection was conducted using a commercially available enzyme immunoassay (EIA). RESULTS: No opportunistic intestinal parasites were identified in this study. Non-opportunistic parasites diagnosed included Giardia lamblia (12.2%) and Ascaris lumbricoides (2.4%) while the commensals Endolimax nana and Entamoeba hartmanni were found in 4.9% and 2.4% of children, respectively. CONCLUSION: Children living with HIV/AIDS in institutions in Jamaica that are closely supervised do not appear to be at substantial risk for intestinal parasites. This may be due to the strict clinical monitoring of the children and personal and environmental hygiene practices.

Seroprevalence of human toxocariasis, Jamaica.

Seroprevalence of human toxocariasis was studied, based on 1544 samples selected from a total of 3524 submitted to the University of the West Indies in Kingston, Jamaica for diagnosis of dengue during an epidemic in 2010. The prevalence of anti-Toxocara IgG using the CELISA® (Cellabs) ELISA was 21.2% and males (24.4%) were significantly more likely to be exposed than females (17.5%) [χ2 =10.4; p=0.001]. No association was foundbetween exposure to Toxocara and area of residence (rural vs. urban) [χ2 =0.835; p = 0.409]. Prevalence of infection peaked in adolescents (10-19 years-old) and declined thereafter although a rise in prevalence was seen in older age classes. There was a high prevalence of toxocariasis in Jamaica with significant exposure among school age children with no predilection to either sex. The study will inform future work on elucidating the public health and clinical significance of toxocariasis in Jamaica.

Short report: long-term serum antibody isotype responses to Strongyloides stercoralis filariform antigens in eight patients treated with ivermectin.

The enzyme-linked immunosorbant assay was used to investigate long-term changes in serum immunoglobulin G1 (IgG1), IgG4, IgE, and IgA against Strongyloides stercoralis phosphate-buffered saline-soluble filariform larval antigens in eight Jamaican patients treated with ivermectin. Patients were followed for periods of between 170 and 542 days. Based on repeated formalin-ether concentration and agar plate culture, all patients were found to be uninfected up to 18 months following chemotherapy. Generally, all antibody isotype levels decreased following treatment, although there was considerable heterogeneity among patients. In a single patient with hyperinfection, the decrease in IgG4 was marginal and may represent a treatment failure. Reduction in serum antibody isotype responses to S. stercoralis following treatment may be used to assess the effectiveness of ivermectin in treating endemic strongyloidiasis.

Epidemiology of giardiasis and cryptosporidiosis in Jamaica.

We report the findings of a cross-sectional epidemiologic study of Giardia lamblia and Cryptosporidum infections in Jamaica. Three hundred twenty eight stool samples from patients less than one to 81 years of age were examined using formalin-ether concentration for G. lamblia, Zeihl-Neelsen staining for Cryptosporidium, and the Prospect rapid enzyme immunoassay (EIA; Alexon, Sunnyvale, CA) for parasite diagnosis. The Prospect Giardia rapid assay detected 17 cases of G. lamblia infection compared with six by formalin-ether concentration. However, the Prospect Cryptosporidum EIA did not increase the rate of detection of Cryptosporidum when compared with Zeihl-Neelsen staining. Cryptosporidum infections were most frequently diagnosed in children less than five years old and prevalence decreased with age. In contrast, the prevalence of giardiasis increased as children became older. There were no associations between the infections and stool consistency, clinical manifestations, or sex of the individuals. The contribution of the parasites to childhood morbidity will depend on accurate laboratory diagnosis.

Fatal autochthonous eosinophilic meningitis in a Jamaican child caused by Angiostrongylus cantonensis.

A fatal case of infection with Angiostrongylus cantonensis is reported in a 14-month-old Jamaican boy. Although infection with Angiostrongylus was not considered initially, sections of multiple worms were observed in the brain and lungs at autopsy and confirmed the infection. This is the first reported fatality due to this infection in the Western Hemisphere, and follows shortly after an outbreak of eosinophilic meningitis among a group of travelers to Jamaica. The source of infection in this case could not be determined.

Prospective evaluation of enzyme-linked immunosorbent assay and immunoblot methods for the diagnosis of endemic Strongyloides stercoralis infection.

Recently described enzyme-linked immunosorbent assay (ELISA) and immunoblot methods for the detection of serum IgG against Strongyloides stercoralis larval antigens were prospectively evaluated for the diagnosis of endemic strongyloidiasis. A modification of the ELISA involved preincubation of sera with Onchocerca gutturosa phosphate-buffered saline-soluble extract to remove cross-reactivity with other helminths. The sensitivity of the ELISA increased from 80% to 85% following preincubation. Similarly, there was an increase in specificity from 94% to 97%. The IgG recognition of 41-, 31-, and 28-kD filariform larval components showed sensitivities of 100%, 85%, and 65%, respectively. Both the ELISA following incubation of sera with O. gutturosa extract and serum IgG reactivity to a 41-kD larval component using immunoblotting are sensitive and specific techniques for diagnosing endemic strongyloidiasis.

Intestinal parasitic infections in human immunodeficiency virus (HIV)-positive and HIV-negative individuals in San Pedro Sula, Honduras.

Honduras has at least five-times more human immunodeficiency virus (HIV)-infected individuals than any other country in Central America. The relationship between HIV status and the presence of intestinal parasites in this part of the world is unknown. This study presents the results from a prospective, comparative study for the presence of parasites in 52 HIV-positive and 48 HIV-negative persons in San Pedro Sula, Honduras. Infection with HIV was determined by microagglutination and confirmed by Western blot analysis. Parasites were detected in stools using formalin-ether concentration, and Kinyoun and trichrome staining. Age, sex, and clinical state of HIV infection were recorded for each study participant. Our results indicate that Cryptosporidium parvum and Strongyloides stercoralis, which are intracellular or live in the mucosa, were found exclusively in persons infected with HIV. In comparison, the prevalence of the extracellular parasites Giardia lamblia, Ascaris lumbricoides, and Trichuris trichiura was significantly higher (P < 0.05) in persons who were HIV-negative. Trichuris worms are in contact with the gut epithelium and less so with the mucosa, whereas Strongyloides lives within the gut mucosa. It is possible that changes in the gut epithelium due to HIV infection do not affect the mucosa and therefore would not affect Strongyloides. We conclude that infection with HIV may selectively deter the establishment of certain intestinal parasites. This may be due to the fact that HIV-induced enteropathy does not favor the establishment of extracellular parasites. Intracellular and mucosal dwelling organisms, however, may benefit from pathologic changes and reduced local immune responses induced by the virus, which, in turn, may lead to higher prevalence among HIV-infected individuals.

Humoral responses in human strongyloidiasis: correlations with infection chronicity.

Strongyloides stercoralis L3-specific antibody isotype responses amongst individuals with known long-standing (28-46 years) infection were compared with those of 'young' (6-29 years of age) and 'old' (30-80 years of age) infected individuals from an endemic Jamaican population. Characterization of age-dependent isotype patterns in the endemic community showed that immunoglobulin (Ig) G1 responses were significantly inversely correlated with age. Additionally, a trend towards lower IgE levels in the older age group was observed. Comparison with responses amongst known chronically infected individuals showed that IgG1 and IgE levels were similar to those of the 'old' endemic group, but were significantly lower than those of the 'young' group. In contrast, IgA levels were similar in both endemic groups, but were elevated in chronically infected individuals. IgG4 levels were similar in all groups studied. These findings suggest that age correlates with infection chronicity in communities endemic for S. stercoralis, and that individuals acquire infection early in their lives and remain infected into adulthood. Early and sustained upregulation of IgG4 may facilitate the establishment of infection and, in combination with developing IgE hyporesponsiveness, may promote chronic asymptomatic strongyloidiasis. Conversely, upregulated IgA may be involved in controlling chronic infection levels which are reflected in reduced IgG1 production.

Immunodiagnosis of Strongyloides stercoralis infection: a method for increasing the specificity of the indirect ELISA.

Indirect enzyme-linked immunosorbent assay (ELISA) allows sensitive detection of serum immunoglobulin (Ig) G against a soluble extract of Strongyloides stercoralis infective larvae. In this study, 40/40 (100%) human strongyloidiasis sera had high levels of anti-S. stercoralis IgG, but 30/40 (75%) filariasis sera, and 12/40 (30%) necatoriasis sera also had higher levels than control sera from UK residents. In attempts to increase the assay specificity by absorption of cross-reactive IgG, the effectiveness of pre-incubation of sera with extracts of different parasitic nematodes was investigated. One hour of incubation with 20 micrograms/ml aqueous extract of Onchocerca gutturosa absorbed cross-reactive IgG in most filariasis and necatoriasis sera, reducing the proportion with IgG levels above the positivity threshold by more than one-half. Preliminary results suggest that absorption with extracts of other filarial nematodes is equally effective, and that some of the cross-reactive IgG is directed against phosphorylcholine. Cross-reactive IgG in most necatoriasis sera was effectively absorbed with 20 micrograms/ml extract of Necator americanus. Cross-reactive IgG was not effectively absorbed with an extract of Ascaris lumbricoides. Absorption of cross-reactive IgG is an effective means of increasing the specificity of the indirect ELISA, for use in the immunodiagnosis and immuno-epidemiology of S. stercoralis infection.

The age-prevalence profile of abdominal obesity among patients in a diabetes referral clinic in Jamaica.

Generalised obesity is a major risk factor for cardiovascular disease, diabetes, hypertension and premature death, but abdominal or central obesity is even more closely related to these. Diabetes causes accelerated atherosclerosis and this results in peripheral vascular and ischaemic heart disease and stroke, major causes of death in diabetics in the Caribbean. Diabetics who have abdominal obesity are therefore at increased risk for these events. 485 patients attending the Diabetes Referral Clinic at the University Hospital of the West Indies, Jamaica, were evaluated for abdominal obesity based on the ratio between their waist and hip measurements. There was an increase in the numbers of diabetics with increasing age. Abdominal obesity was significantly more prevalent among females (90%) than among males (34.9%) (mean 2 = 142; p < 0.0001), and massive obesity was detected in 31.1% of females. However, the prevalence of abdominal obesity among males and females was not significantly age-related. Given the high prevalence of obesity in this clinic population, more precise studies of abdominal obesity associated morbidity in diabetics should be undertaken.

Cutaneous furuncular myiasis in a Jamaican resident.

Data are presented on a case of cutaneous furuncular myiasis in a Jamaican resident. This condition is virtually unknown in the Caribbean, but is endemic in Central and South America. The infection, which was caused by Dermatobia hominis, was acquired in Belize and was misdiagnosed and treated as infected insect bites. Cutaneous furuncular myiasis should be considered in patients with sub-acute inflammatory nodular skin lesions with a history of recent travel to endemic countries.

Inactivation of strongyloides stercoralis filariform larvae in vitro by six Jamaican plant extracts and three commercial anthelmintics.

In vitro bioassay of (a) aqueous methanol extracts (AME) of the green leaves of mimosa (Mimosa pudica), love weed (Cuscuta americana), vervine (Stachytarpheta jamaicensis), chicken weed (Salvia serotina) and breadfruit (Artocarpus altilis); (b) methanol-water fraction (MWF) of breadfruit leaves, and (c) commercially available drugs albendazole, thiabendazole and levamisole were assayed for nematode inactivating potential, using filariform larvae of Strongyloides stercoralis. Test larvae were obtained from a 10-day-old charcoal coproculture. Bioassays were conducted in Locke's solution, using 100 larvae in each of three replicates. Inactivation was recorded microscopically at 1, 3, 6 and 12 hours, then every 24 hours up to 5 days' incubation. It50 (time for inactivation of 50% of larvae) values read: levamisole and mimosa extract less than 1 hour; love weed extract, approximately 2 hours; breadfruit (MWF), 9.5 hours; chicken weed, 20 hours; albendazole, 35 hours; breadfruit (AME), 49 hours; thiabendazole, 74 hours and vervine extract, 81.5 hours. It95 values followed a similar, trend, and were approximately double the It50 measures. A potential role for locally available natural products in the treatment of strongyloidiasis is highlighted.

Dialysis adequacy at two haemodialysis units in Jamaica.

A prospective study on adequacy of dialysis was conducted at the haemodialysis units of Kingston Public Hospital (KPH) and the University Hospital of the West Indies (UHWI). Dialysis adequacy was better at KPH and morbidity, as measured by patient admission days, was increased at UHWI. Diabetics had a lower mean serum albumin and urea reduction ratio (URR) than non-diabetics. Multiple regression analyses revealed that age of patient (F = 5.30; p = 0.0241) and hospital (F = 7.85; p = 0.007) were the variables significantly associated with serum albumin level when the effect of other variables was controlled (F = 2.12; p = 0.34). Similar analyses showed that the hospital at which dialysis was done was the only factor which accounted for significantly higher URR, with KPH having higher rates (F = 13; p = 0.006). The differences between hospitals necessitate further investigations, explanations and intervention strategies. The study provides opportunities for improving patient care and for dialysis health care professionals to assess clinical performance measures and reduce variation between dialysis centres.

A sonographic study of kidney dimensions in a sample of healthy Jamaicans.

A sonographic study of 49 randomly selected healthy adult Jamaicans was conducted to establish a guide for renal dimensions in the population. The mean length of the right kidney was 9.7 +/- 0.7 cm and the left 10 +/- 0.7 cm. The left kidney was longer than the right in the overall group and in males. There was no difference in width between right or left kidneys in the group as a whole or within either gender. There was a significant association between the weight of males and width of their kidneys; however, this association was not seen in females. The lone association between weight of participants and renal length occurred in females and only with respect to the left kidney. Lengths and widths of kidneys were not associated with height in either gender. Renal surface area (RSA) was similar between the genders and also between right and left kidneys. Similarly, there was no significant association between renal length and body surface area (BSA) overall or within the genders. Renal index (RI) which is more reliable at assessing renal parenchymal mass than renal length alone was 20.92 and 22.86 for the right and left kidneys, respectively, in males. Similarly, RI for the right and left kidneys in females was 23.76 and 25.54, respectively.

Intestinal parasites among young children in the interior of Guyana.

Intestinal parasites contribute greatly to morbidity in developing countries. While there have been several studies of the problem in the Caribbean, including the implementation of control programmes, this has not been done for Guyana. The aim of this study was to determine the prevalence of intestinal parasites among young children in a town located in the interior of Guyana. Eighty-five children under the age of 12 years were studied prospectively for intestinal parasites in Mahdia, Guyana. Stool samples were transported in formalin to the Department of Microbiology, The University of the West Indies, Jamaica, for analysis using the formalin-ether concentration and Ziehl-Neelsen techniques. Data on age and gender of the children were recorded on field data sheets. At least one intestinal parasite was detected in 43.5% (37/85) of the children studied and multiple parasitic infections were recorded in 21.2% (18/85). The most common intestinal helminth parasite was hookworm (28.2%; 24/85), followed by Ascaris lumbricoides (18.8%; 16/85) and then Trichuris trichuria (14.1%; 12/85). Among the protozoan infections Giardia lamblia was detected in 10.5% (9/85) of the study population while Entamoeba histolytica appeared rarely. All stool samples were negative for Cryptosporidium and other intestinal Coccidia. There was no predilection for gender with any of the parasites. The pattern of distribution of worms in this area of Guyana was unlike that seen in other studies. Hookworm infection was the most common among the children and a large proportion had multiple infections. The study established the occurrence and prevalence of a number of intestinal parasites in the population of Guyana. This sets the stage for the design and implementation of more detailed epidemiological studies.