The control of hookworm disease in Commonwealth Caribbean countries.

Like other countries around the globe where conditions existed for the parasites causing hookworm disease to thrive, this disease was a serious problem to settlers in countries of the Commonwealth Caribbean, i.e. those countries that were formerly part of the British Empire.

Seasonal abundance, biting cycle and parity of the mosquito Haemagogus leucocelaenus in Trinidad, West Indies.

Adult female populations of Haemagogus leucocelaenus (Dyar and Shannon), the sylvan vector of yellow fever, were monitored weekly during 1981-82 by human collectors on the ground at Point Gourde in Chaguaramas Forest, 16 km west of Port of Spain, Trinidad. Hg.leucocelaenus showed only diurnal landing activity, from 06.

Seasonal abundance, biting cycle, parity and vector potential of the mosquito Haemagogus equinus in Trinidad.

The mosquito Haemagogus equinus is a known vector of yellow fever (YF) in central America. Seasonal abundance, daily biting activity and the age composition of adult Hg.equinus female populations were monitored weekly during 1981-82 by human collectors on the ground at Point Gourde Forest, Chaguaramas, 16 km west of Port of Spain, Trinidad.

Significant changes in gastrointestinal tract parasitic infections in children of St. Kitts over the 9-year period 1982-1991.

When 239 (1982) and 361 (1991) five- and nine-year-old children in St. Kitts were assessed for the presence of parasitic infections, there were significant reductions in the prevalence of trichuriasis from 83% to 58%, of ascariasis from 24% to 8.6% and of giardiasis from 15% to 9.

Suppression of Aedes aegypti by predatory Toxorhynchites moctezuma in an island habitat.

Larval populations of the mosquito Aedes aegypti were suppressed by predatory Toxorhynchites moctezuma mosquito larvae released systematically in a village on Union Island (Saint Vincent and the Grenadines) during March-December 1988. Eggs and larvae of Tx.moctezuma were transported from Trinidad and introduced into all semi-permanent and permanent water-holding containers in the experimental village at Clifton.

Effects of Toxorhynchites moctezuma larval predation on Aedes aegypti populations: experimental evaluation.

Predatory larvae of the mosquito Toxorhynchites moctezuma were used experimentally to control a standing crop of larvae of the dengue vector mosquito Ae.aegypti. Each week, fifty Ae.

Distribution and seasonality of Culex (Melanoconion) caudelli, a vector of arboviruses in Trinidad.

Seasonal and spatial distributions of the arbovirus vector mosquito Culex (Melanoconion) caudelli Dyar and Knab (Diptera: Culicidae) in the Aripo-Wallerfield forest, Trinidad, were studied by collecting mosquitoes attracted to mouse-baited traps in forest, ecotone and savannah, one day per week throughout the year, 98% of the Cx caudelli mosquitoes were collected during the wet season, with a significant positive correlation between rainfall and mosquito catch. The reverse occurred during the dry season. Cx caudelli displayed a preference for the ecotone where 67% were collected, while 32% and 1% were collected in the forest and savannah respectively.

Seasonality, biting cycle and parity of the yellow fever vector mosquito Haemagogus janthinomys in Trinidad.

1. Age composition, seasonal abundance and diel patterns of landing activity of the sylvan vector of yellow fever Haemagogus janthinomys Dyar were monitored weekly during 1981-82 by human collectors on the ground at Point Gourde in Chaguaramas Forest, 16 km west of Port of Spain, Trinidad. 2.

Laboratory colonization and maintenance of Toxorhynchites moctezuma.

A colony of Toxorhynchites moctezuma was established at the Caribbean Epidemiology Centre in Trinidad in 1984. Toxorhynchites moctezuma was maintained in cages with high humidities. Eggs were deposited most frequently in a cut bicycle tire containing water.

Visceral larva migrans in seven members of one family in Trinidad.

The occurrence of the first seven cases of visceral larva migrans in Trinidad and Tobago is described. All cases occurred in children of the same family. The ELISA test was used to confirm the clinical diagnosis.

Seasonal incidence and diel oviposition periodicity of Haemagogus mosquitoes (Diptera: Culicidae) in Trinidad, W.I. Part III. Haemagogus celeste (Dyar and Nunez Tovar) and Haemagogus leucocelaenus (Dyar and Shannon).

The seasonal incidence and diel oviposition patterns of sylvan Haemagogus celeste and Hg. leucocelaenus in the Pt. Gourde Forest, Trinidad, were monitored weekly for 53 consecutive weeks using conventional ovitraps.

Observations on the seasonal incidence and diel oviposition periodicity of Haemagogus mosquitoes (Diptera: Culicidae) in Trinidad, W.I. II. Haemagogus equinus Theobald.

Diel patterns of oviposition of sylvan Haemagogus equinus in the field in Trinidad, West Indies, were monitored weekly for 53 consecutive weeks using standard ovitraps. During the wet season (September to November 1981 and May to September 1982) a large well-defined unimodal peak (comprising 97% of all eggs laid and 89% of occurrences) occurred at 12.00-14.

Blastocystis hominis in two children of one family.

Two apparently healthy children from the same family were found to have moderate to heavy Blastocystis hominis in their stool samples whilst being investigated for intestinal symptoms: sporadic, painless, rectal bleeding in one and persistent diarrhoea in the other. After treatment with metronidazole, they had no further signs, and stool samples became negative. Eighteen months later, both were asymptomatic, and stool samples continued to be negative for the parasite.

Observations on the seasonal incidence and diel oviposition periodicity of Haemagogus mosquitoes (Diptera: Culicidae) in Trinidad, W.I.: Part I. Haemagogus janthinomys Dyar.

The diel oviposition periodicity of sylvan Haemagogus janthinomys Dyar in the Pt. Gourde Forest, Trinidad, West Indies was monitored weekly for 53 weeks using conventional ovitraps. During the wet season (September to November 1981 and May to September 1982) a large well-defined unimodal peak occurred six to eight hours after sunrise (comprising 94% of eggs laid and 91% occurrences).

A laboratory investigation of mosquito larval predation by Toxorhynchites moctezuma on Aedes aegypti.

1. Functional responses of predatory Toxorhynchites moctezuma (Dyar & Knab) larvae feeding on Aedes aegypti (L.) larvae (Diptera: Culicidae) were found to be type II of Holling (1959) and Rogers (1972).

Diel biting activity of Culex (Melanoconion) caudelli in Trinidad, West Indies.

The diel biting periodicity of the arbovirus vector Culex (Melanoconion) caudelli Dyar and Knab (Diptera; Culicidae) in the Aripo-Wallerfield forest, Trinidad, was studied by collecting mosquitoes attracted to mouse-baited traps at 2-hourly intervals during eight 24 h periods. Biting females of Cx caudelli were collected during all night-time hours, 18.00-06.

Bancroftian filariasis in coastal north Trinidad: the effects of mass chemotherapy using spaced doses of diethylcarbamazine citrate on human microfilaraemias and vector infection rates.

The effects of a mass chemotherapy programme using spaced doses of diethylcarbamazine citrate on Wuchereria bancrofti microfilaraemias and vector infection rates were studied in an isolated rural community of 650 people in north Trinidad where a microfilaria rate of 15% had previously been recorded. A single oral dose of 6 mg/kg body weight was given at monthly intervals for one year. After 6 months, 79% (52/66) of persons previously microfilaraemic had become negative.

Natural transovarial transmission of dengue 4 virus in Aedes aegypti in Trinidad.

The isolation of dengue 4 virus from adult Aedes aegypti, reared from eggs collected in nature, is reported for the first time. From the locality where the isolate was made, 25 pools consisting of 1,848 Ae. aegypti reared from eggs were processed.

Filariasis in Amerindians of western Guyana with observations on transmission of Mansonella ozzardi by a Simulium species of the amazonicum group.

In order to conduct experimental infection studies of Mansonella ozzardi in local haematophagous Diptera, volunteers infected with this parasite were identified during a microfilaria survey in four Amerindian villages in the Pakaraima Mountains of western Guyana, near the Brazilian border. M. ozzardi microfilariae were detected in thick blood smears from 8-21% of persons examined.

Avian pox in birds from Trinidad.

Over a 7-year period in Trinidad, 9,514 birds were examined for avian pox and four species were found infected: the golden-headed manakin, Pipra erythrocephala (7% infected), the white-bearded manakin, Manacus manacus (5%), the violaceous euphonia Euphonia violacea (1%), and the bare-eyed thrush, Turdus nudigenis (less than 1%). The elaborate courtship displays of manakins may have a bearing on a "common source" type of infection. The apparently abrupt appearance of the disease at three localities in Trinidad in 1964 perhaps indicates introduction of the virus by migratory birds.