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.

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.

Identification of Anopheles aquasalis as a possible vector of malaria in Guyana, South America

Adult female mosquitoes were collected in Mahdia, Guyana, to determine the incidence of malaria in Anopheles species found during the month of June 2000. Centers for Disease Control miniature white (incandescent) light traps, model 512, and miniature black (ultraviolet) light traps, model 912, were used to capture female mosquitoes. Numbers of mosquitoes collected were compared between white and black light traps and between traps set outside and inside of buildings. Adult female Anopheles mosquitoes were identified and an ELISA dipstick test for Plasmodium vivax and Plasmodium falciparum was performed on each mosquito. An aquasalis, An oswaldoi, and An braziliensis were attracted to white light traps. An triannulatus and An darlingi were collected from black light traps. Approximately the same numbers of all female Anopheles mosquitoes 28/45 (62) were caught inside buildings as outside. Numbers of female non-anopheles mosquitoes captured in light traps varied between the traps set outside of buildings and inside of buildings with bright light traps collecting 91/122 (75). A total of 45 Anopheles mosquitoes were captured and 122 non-anopheles species. Of the two known vectors of malaria in Guyana, An darlingi mosquitoes were not infected with P vivax but An aquasalis was found to be a carrier. The findings of this study suggest a need for further surveying and identification of current malaria vectors in Guyana.

Identification of Anopheles aquasalis as a possible vector of malaria in Guyana, South America.

Adult female mosquitoes were collected in Mahdia, Guyana, to determine the incidence of malaria in Anopheles species found during the month of June 2000. Centers for Disease Control miniature white (incandescent) light traps, model 512, and miniature black (ultraviolet) light traps, model 912, were used to capture female mosquitoes. Numbers of mosquitoes collected were compared between white and black light traps and between traps set outside and inside of buildings. Adult female Anopheles mosquitoes were identified and an ELISA dipstick test for Plasmodium vivax and Plasmodium falciparum was performed on each mosquito. An aquasalis, An oswaldoi, and An braziliensis were attracted to white light traps. An triannulatus and An darlingi were collected from black light traps. Approximately the same numbers of all female Anopheles mosquitoes 28/45 (62%) were caught inside buildings as outside. Numbers of female non-anopheles mosquitoes captured in light traps varied between the traps set outside of buildings and inside of buildings with bright light traps collecting 91/122 (75%). A total of 45 Anopheles mosquitoes were captured and 122 non-anopheles species. Of the two known vectors of malaria in Guyana, An darlingi mosquitoes were not infected with P vivax but An aquasalis was found to be a carrier. The findings of this study suggest a need for further surveying and identification of current malaria vectors in Guyana.

Field evaluation of the Determine rapid human immunodeficiency virus diagnostic test in Honduras and the Dominican Republic.

Rapid detection of human immunodeficiency virus (HIV) infection can result in improved patient care and/or faster implementation of public health preventive measures. A new rapid test, Determine (Abbott, Abbott Park, Ill.), detects HIV type 1 (HIV-1) and HIV-2 antibodies within 15 min by using 50 microl of serum or plasma. No specialized equipment or ancillary supplies are required, and results are read visually. A positive result is noted by the appearance of a red line. An operational control (red line) indicates proper test performance. We evaluated the Determine rapid HIV detection test with a group of well-characterized serum samples (CD4 counts and viral loads were known) and serum samples from HIV-positive individuals at field sites in Honduras and the Dominican Republic. In the field evaluations, the results obtained by the Determine assay were compared to those obtained by local in-country HIV screening procedures. We evaluated serum from 100 HIV-positive patients and 66 HIV-negative patients. All samples gave the expected results. In a companion study, 42 HIV-positive samples from a Miami, Fla., serum bank were tested by the Determine assay. The samples had been characterized in terms of CD4 counts and viral loads. Fifteen patients had CD4 counts <200 cells/mm(3), while 27 patients had CD4 counts >200 cells/mm(3). Viral loads ranged from 630 to 873,746 log(10) copies/ml. All samples from the Miami serum bank were positive by the Determine test. Combined results from the multicenter studies indicated that the correct results were obtained by the Determine assay for 100% (142 of 142) of the HIV-positive serum samples and 100% (66 of 66) of the HIV-negative serum samples. The Determine test was simple to perform and the results were easy to interpret. The Determine test provides a valuable new method for the rapid identification of HIV-positive individuals, especially in developing countries with limited laboratory infrastructures.

Dengue in Guyana.

There have been dramatic increases in dengue fever (DF) and dengue haemorrhagic fever in South America. Guyana has reported less than five cases per year for most of the past decade. We evaluated patients in a clinic in Georgetown, Guyana, over 2 days and found evidence of 50 cases of dengue infection.

PIP: This research letter evaluates the incidence of dengue fever and dengue hemorrhagic fever in Guyana, South America, in a study conducted at the Vector Control Medical Center on July 20-21, 1998. Venous blood samples were collected from 112 patients (99 men and 13 women ranging in age from 9 to 60 years) who were inflicted with fever, chills, malaise, and/or headache. 50 samples were detected to be dengue virus- positive, illustrating a 45% prevalence of recent dengue virus infection among the tested patients. This study revealed that the incidence of dengue fever in Guyana is under-reported. Thus, improvements should be made in the surveillance measures for dengue infection in Guyana and its surrounding countries.

Dengue in Guyana

Evaluates patients in a clinic in Georgetown, Guyana for dengue fever and dengue hemorhagic fever. Evidence of 50 cases of dengue infection; Guyana reporting less than five cases per eyar for most of the 1990s; Suggestion for surveillance measures for dengue virus infections in Guyana and surrounding countries.(AU)

Evaluation of the MRL diagnostics dengue fever virus IgM capture ELISA and the PanBio Rapid Immunochromatographic Test for diagnosis of dengue fever in Jamaica

We evaluated two new commercial dengue diagnostic tests, the MRL Diagnostics Dengue Fever Virus IgM Capture ELISA and the PanBio Rapid Immunochromatographic Test, on serum samples collected during a dengue epidemic in Jamaica. The MRL ELISA method correctly identified 96 percent (78 of 80) of the samples as dengue positive, while the PanBio test identified 100 percent (80 of 80). Both tests were 100 percent (20 samples of 20) specific.(Au)

Evaluation of the MRL diagnostics dengue fever virus IgM capture ELISA and the PanBio Rapid Immunochromatographic Test for diagnosis of dengue fever in Jamaica.

We evaluated two new commercial dengue diagnostic tests, the MRL Diagnostics Dengue Fever Virus IgM Capture ELISA and the PanBio Rapid Immunochromatographic Test, on serum samples collected during a dengue epidemic in Jamaica. The MRL ELISA method correctly identified 98% (78 of 80) of the samples as dengue positive, while the PanBio test identified 100% (80 of 80). Both tests were 100% (20 samples of 20) specific.

Gapeworm infection of domestic cats in Puerto Rico.

In a survey of 40 adult cats in Puerto Rico, 13 (33%) were found to be infected with the gapeworm Synagamus (Mammomonogamus) ierei. Direct fecal smear and necropsy were the methods used to detect the infection. Fourteen adult worm pairs were collected in one cat; the average was four. Histologically, evidence of chronic inflammation was observed in the nasopharynx of infected cats. The parasite occurs widely in the Caribbean region. It was concluded that the similarity of the gapeworm egg with those of hookworms and the recondite location of the adult gapeworm probably explain the lack of reports on the infection.

Antibodies of influenza viruses in military recruits from Argentina, Brazil and Colombia. Their relation to ABO blood group distribution.

In a large-scale seroepidemiological study, the prevalence was determined of antibodies to influenza A viruses in the sera of military representative of the inhabited geographical regions of Argentina, Brazil and Colombia. The micro-haemagglutination-inhibition test was used against the Swine, PR/8, FM/1 and Asian antigenic strains. From each of the three recruit populations 500 sera were tested.Positive titres to the FM/1 and Asian strains were found in 72% and 80% respectively of the Colombian sera, in 56% and 69% of the Argentinian sera, and in 49% and 63% of the Brazilian sera. Of these 1500 sera, 5 were positive to the PR/8 strain and 2 to the Swine strain.This study also showed that there were highly significantly greater proportions of positive reactors to the FM/1 and Asian strains among persons of blood groups O and B than among those of blood group A in all three countries.