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H Schenone

Publications and source records attributed to H Schenone.

At least 73 records · Page 4Linked to original sources
PubMedDate not supplied

[Epidemiology of toxoplasmosis in Chile. VI. Prevalence of human infection, investigated by means of an indirect hemagglutination test, in regions VII, VIII and IX].

In presecuting the investigations on the epidemiology of toxoplasmosis in Chile, a new series of serological surveys has been performed during 1982-1989 in 10 urban and 25 periurban-rural localities from the regions VII, VIII and IX of the country (34 degrees 41'-39 degrees 38' South lat.). In 9,758, randomly selected apparently healthy persons, and indirect hemagglutination test (IHAT) for toxoplasmosis was carried out. The age of these individuals (4,203 males and 5,555 females) varied between 4 and 84 years. The examined persons represent a 0.33% of the total population of the three studied regions. IHAT titers of 1: > or = 16 were regarded as positive. The global prevalence for positive IHAT was 45.5% (50.5% in men and 41.7% in women). A higher proportion of positive tests was observed in urban areas (47.0%) than in periurban-rural sections (33.3%). An increasing prevalence with age was also observed. Only 5 (0.05%) persons had IHAT titers higher than 1:1000.

Adolescent↗
PubMedDate not supplied

[Epidemiology of toxoplasmosis in Chile. VII. Prevalence of human infection investigated by means of indirect hemagglutination reaction in the regions X, XI and XII].

In pursuing the studies on the epidemiology of toxoplasmosis in Chile, a recent series of surveys have been undertaken in 1983-1990 in 4 urban and 22 periurban-rural localities from regions X, XI and XII of the country (39 degrees 38'-56 degrees 00' South lat.). An indirect hemagglutination test (IHAT) for toxoplasmosis was performed to 6,438 randomly selected apparently healthy persons. The age of the surveyed persons (2,779 males and 3,659 females) varied between 1 and 93 years. The number of examined persons represents a 0.61% of the total population of the three studied regions. IHAT titers of 1: > or = 16 were considered as positive. The general prevalence for positive IHAT was 46.3% (47.4% in men and 45.4% in women). Similarly to other regions, a higher proportion of positive reactors was detected in urban sections (49.0%) than in periurban-rural ones (40.3%). An increase of prevalence with age was also observed. Only 8 (0.12%) persons presented IHAT titers higher than 1:1000.

Adolescent↗
PubMedDate not supplied

[Incidence of infection by intestinal parasites among school children in Santiago, Chile, 1988-1989].

In December 1988-February 1989 period, a survey on enteroparasitic infections in children (mean age 8.7 years; males 54.4% and females 45.6%) from five schools located in Santiago, Chile, was undertaken. To each of these individuals, three samples were obtained in order to perform in them the following examinations: co-proparasitological study, modified Ziehl-Neelsen staining for detecting Cryptosporidium sp. and cellulose adhesive test for Enterobius vermicularis. Parasitic elements were found in the following percentages: Blastocystis hominis 51.8, Enterobius vermicularis 39.9, Giardia lamblia 32.1, Entamoeba histolytica 7.8, Hymenolepis nana 2.1 and Ascaris lumbricoides 0.4, Cryptosporidium sp. were not observed. The present study would be demonstrating that enteroparasites maintain their endemic condition among school children from Santiago, including B. hominis which had not been searched previously.

Adolescent↗
PubMedDate not supplied

[Cysticercosis and hydatidosis do not always bring about detectable pathology in humans].

The clinical pictures produced in man by cysticercosis and hydatidosis are well known, not being infrequent the occurrence of fatal cases. Nevertheless, retrospective studies, carried out in autopsies, have permitted to demonstrate that only about one third on the cases of each of one of the quoted parasitoses, were caused by the corresponding etiologies. In this respect, in a study performed in Santiago, Chile between 1947 and 1984, which included the revision of 189,909 autopsy protocols, it was possible to verify that out of 116 neurocysticercosis cases 79 (68.1%) corresponded to autopsy findings, whereas out of 568 hydatidosis cases, 363 (63.9%) were autopsy findings, without a previous clinical history suggesting the respective parasitosis and not depending of the location of the parasite.

Central Nervous System Diseases↗
PubMedDate not supplied

[Problems related to the diagnosis of Chagas' disease].

Trypanosoma cruzi may be transmitted to a susceptible human through different routes: a superficial lesion in the skin, such as a scraping of the small wound produced by the hematophagous triatomid bug vector, which becomes infected with its contaminated feces; the placenta, from the infected mother to the product of conception; a transfusion from an infected donor, or even by ingestion of diverse foods infected or contaminated with the parasite. Whichever may be the transmission of the protozoon, it is advisable to have in mind that it is able to produce an asymptomatic or a symptomatic infection, being possible in both cases, using appropriated methods, to detect the T. cruzi and/or the antibodies generated. From the clinical stand-point, Chagas' Disease may present itself as acute or as a chronic disease. Habitually, the acute disease is characterized by general involvement, fever, hepato-splenomegaly, polidenopathy, and occasionally myocarditis and/or encephalitis, whereas, the chronic form of the disease is characterized by presenting itself in an isolated way or combined, chronic myocardiopathy, megaesophagous or megacolon. At any rate, the problems center in the possibility of a reasonable diagnostic assurance which permits the adoption of adequate therapeutic measures. Some facts, which may help to confront these problems are: a) The epidemiological antecedents (origin in an endemic area, personal knowledge of the vector or of being bitten by it, whether the mother or other relatives are affected by the disease, etc.).(ABSTRACT TRUNCATED AT 250 WORDS)

Chagas Disease↗
PubMedDate not supplied

[Pragmatic data and observations related to the epidemiology of Chagas disease].

Chagas' disease or American trypanosomiasis is a parasitic zoonosis which constitutes and important public health problem in most of the Latin American countries. According to the development of socio-political events in the world, it is possible at present to speak of rural-periurban Chagas' disease and urban Chagas' disease. Rural-periurban Chagas' disease. In its endemo-enzootic condition it is distributed in vast areas from Mexico in the north and Argentina and Chile in the south. It is calculated that the population at risk is about 90 million persons, not less than 16-18 million are Trypanosoma cruzi infected and approximately 38% of these present or have presented pathology caused by the parasite. Organs most frequently affected: heart, esophagus and colon. The corresponding biological vectors are hematophagus triatomid bugs, with greater than 100 species synantropic (st) or sylvatic (sv), existing between parallels 41 N. and 46 S., but only about 36, which have been found infected, have some relationship with man because their adaptation to human dwelling. The human parasitose is less extended due to the fact that the vectors of the region are predominantly sv. The known reservoirs are more than 180 species of terrestrial mammals: domestic, st and sv. Man is possibly the most important. Some available relevant epidemiological information is summarized as follows: Additionally, some autochthonous cases of T. cruzi human infection have been registered in the United States, Trinidad-Tobago, Guyana and Belize. Moreover, infected vectors and/or sv reservoirs have been observed in almost a dozen of Caribbean countries. Urban Chagas' disease. As a consequence of possible better salaries and many other motivations, in the last decades there have been significant and constant migrations from rural to urban areas in many Latin American countries. This situation has facilitated the dissemination of T. cruzi infection through infected reservoirs--mostly humans--and/or passively transported infected vectors. In most of the cases these rural-urban migrations occur in chagasic endemic areas within a same country or in neighbouring ones; in others, the migration can involve countries where Chagas' disease does not exist, transmission being via blood transfusion or placental. According to some estimates, with a mean rate of 1.5% chagasic infected blood donors the minimum risk of T. cruzi transmission is nearly 12.5-25.0% when the volumen of transfused blood is 500 ml.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMedDate not supplied

[Epidemiology of toxoplasmosis in Chile. V. Prevalence of the infection in humans and domestic and wild animals, studied by indirect hemagglutination reaction, in the Juan Fernández Archipelago. V Region].

A serological study utilizing an indirect hemagglutination test (IHAT) for toxoplasmosis was carried out in 222 humans and in 58 domestic animals (31 dogs, Canis familiaris; 27 cats, Felis catus), and in 62 wild mammals distributed into 50 rabbits, Oryctolagus cuniculus and 12 goats, Capra hircus. This survey was performed in the Juan Fernández Archipelago, formed by three islands: Robinson Crusoe, Santa Clara and Alejandro Selkirk (80 degrees 47'-78 degrees 47' west long., and 33 degrees 36'-33 degrees 47' south lat.). Blood samples were collected in filter paper and IHAT with titres greater than or equal to 1:16 were considered positive. This survey showed a prevalence of 42.3% in humans with no difference between men (43.0%) and women (41.5%). A high prevalence was found within groups of young individuals (0 to 19 years old), men and women. Regarding the domestic animal population, 44.8% resulted positive, distributed as follows: dogs 9.7% and cats 85.2%. Twenty one percent of wild animals were positive, distributed as follows: rabbits 8.0% and goats 75.0%. The global prevalence of toxoplasmosis in animals (domestic and wild) was 32.5%. All titres in humans and animals were less than or equal to 1:512. Toxoplasmosis is well extended among the human and animal population of the Juan Fernández Archipelago.

Adolescent↗