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H Schenone

Publications and source records attributed to H Schenone.

227 records · Page 13Linked to original sources
PubMedDate not supplied

[Evaluation of a triatoma infestans eradication program in rural dwellings from the IV region, Chile, by means of serology for Chagas disease in 0-10 years old children].

The present study deals with the evaluation of the effectiveness of the measures employed in the control of Triatoma infestans, the vector of Trypanosoma cruzi infection (Chagas' disease), in the IV region of Chile through a serological follow up program. For this reason, a serological survey has been carried out in 2,783 children, from 0 to 10 years, who live in rural high endemic areas of the region. The sera were tested using an indirect hemagglutination test (IHAT) and ELISA techniques with results agreeing in 99.9% of the samples. In children with positive serology xenodiagnosis was performed and blood samples from the corresponding mothers were submitted to serology for Chagas' disease. These additional tests should allow to distinguish between congenital infection and vectorial transmission. It was observed that vectorial transmission of T. cruzi was interrupted in some localities where entomological control has been applied for 10 years, or lowered in those which have been submitted to desinsectations in the last 5 years. On the other hand, a relatively high prevalence of the infection has been detected in some localities. These results suggest an apparent increase of vectorial transmission, indicating the need of readjusting the dwellings insecticide sprayings activities to improve the measures against the vector.

Animals↗
PubMedDate not supplied

[Diagnosis in 1348 patients which consulted for a probable spider bite or insect sting].

Accumulate experience, from 1955 to 1995, in an outpatient university parasitology clinic in Santiago, with 1,384 patients referred from diverse public and private medical institutions because of a probable spider bite or insect stings, is presented. It is noteworthy that only 618 (44.7%) of consultations corresponded to clinical conditions originated by arthropods, whereas from the remaining 766, 612 (44.2%) were due to a bacterial, viral or parasitic etiology and 154 (11.1%) were caused by physical or chemical agents. Frequency of diagnosis was: loxoscelism 16.6%, spider bites (excluded Loxosceles laeta) 1.3%, scorpion sting 0.9%, tick stings 2.2%, insect bites 23.7%, impetigo 6.6%, folliculitis 11.3%, boil 22.7%, erysipelas 0.1%, pustula maligna 0.3%, herpes simplex 2.5, palpebral herpes zoster 0.3%, acute Chagas' disease 0.4%, angioneurotic edema 0.1%, ecchymosis 3.0, contact dermitis 7.8% and chemical dermitis 0.2%. These frequencies do not indicate the real occurrence of the diagnosed nosologies, but what happened in a specialized outpatient clinic dealing cheaply with parasitic diseases and arthropod envenomations. Description of relevant clinical features and epidemiological considerations of pathology observed, conjointly with differential diagnosis are presented.

Angioedema↗
PubMedDate not supplied

[Chagas disease: impact of Triatoma infestans control program in Alto del Carmen, Huasco Province, III Region Atacama, Chile].

A control program of Triatoma infestans has been carried out in Alto del Carmen, an endemic chagasic rural county in the III Region, Chile. The program started in 1988 with an attack phase consisting in a masshouse spraying with residual insecticide, followed by an entomological surveillance phase with health education for community participation and vector detection in eventually reinfested houses. A yearly evaluation in 1992, 1993, 1994 and 1995 was carried out in order to determine the effectiveness of vector control activities. In 1992, 24.1% of dwellings was infested, whereas in 1993, 1994 and 1995 the infestation rates were 3.9%, 2.8% and 4.0% respectively. The similar infestation rates found in 1993, 1994 and 1995 suggest passive dispersion of triatomas from areas without surveillance. Additionally, in 1994, 110 (16.0%) out of 688 examined people resulted serologically positive. It is noteworthy that all of the children in the 0-4 year age group--born after the attack phase--resulted serologically negative. This fact may indicate the interruption of vectorial transmission of Chagas' disease in Alto del Carmen county. It is concluded that the control activities performed in the county constitute good strategies to the Nacional Program of Control of T. infestans, but for the success of such a program it is necessary to integrate the efforts of all endemic areas with an active community participation.

Adolescent↗
PubMedDate not supplied

[Evaluation of vectors of Chagas' disease eradication programs in Chile by serological study of children under 10 years old].

Chagas' disease is a parasitic zoonosis with high prevalence in Chile. It is distributed in rural and periurban section in the northern most seven out of thirteen regions in which the country is divided, and affects about 142,000 individuals dispersed in most of the 165 counties sited in the chagasic zone. Triatoma infestans--intradomiciliary species--is the main and practically exclusive vector of Trypanosoma cruzi. Diverse tools may be utilized in order to interrupt the domestic cycle of transmission of T. cruzi: health education, housing improvement and elimination of vectors by dwelling insecticide sprayings. This last resource has received priority in Chile in the last 12 years. To evaluate the effectivity of the programs for eliminating T. infestans a serological study for Chagas' disease--comprising 8,767 children less than 10 years old from 27 rural counties insecticide sprayed in the last 12 years--was carried out. A global total of 125 (1.4%) children resulted positive, figure significantly lower than 5.4% found in 1982-1990 in the same age group. Distribution by regions of positive individuals showed a decrease of prevalence in each of them: III Region, from 9.8 to 1.0%, IV Region, 7.2 to 2.0%, V Region, 5.2 to 1.9%, and Metropolitan Region, 1.4% to 0.6. Even though positive children have still been found in 46.7% of localities of the studied counties, it is possible to affirm that the vector control programs have been effective and must be maintained, and increased in those localities with T. cruzi infection in children under 10 years of age, with the general aim of eradicate Chagas' disease transmission in Chile before 2000.

Animals↗
PubMedDate not supplied

[Current trends of the epidemiology of human trichinosis in Chile].

Surveillance of the epidemiology of human trichinosis in Chile has been maintained during the last 30 years by the Department of Parasitology. Incidence and prevalence have been followed-up by analysing Ministry of Health annual reports and periodical phototrichinoscopic examination of diaphragm samples from individuals autopsied at the Santiago Medico Legal Service. A decrease has been observed on: incidence from 1.4 per 100,000 in the 1960s to 0.7 in the 1980s down to 0.3 in 1993 and 1994 and to 0.5 in 1995, and prevalence from 3.4% to 2.8%, 2.0% and 0.8% in 1972, 1982, 1992 and 1997 respectively. A predominance of the prevalence in the groups of more age, with the observation of calcified Trichinella spiralis larvae should be indicating a decline of new infections in the general population. This decrease of frequency of human trichinosis in Chile is possible due to the interaction of two main factors, efficacy and higher implementation of control measures and significant advances in porcine technology with a resulting provision to consumers of pork from young animals practically trichinosis free.

Adolescent↗
PubMedDate not supplied

[Immunodiagnosis in 647 suspected clinical cases of toxoplasmosis].

Though Toxoplasma gondii can cause severe pathology in human, in most of the cases it produces only asymptomatic infection. So, it is important to dispose some methods capables to discriminate between acute and chronic infections. An indirect hemagglutination test (IHAT), dye test (DT) and complement fixation test (CFT) were performed in 647 sera from patients suspected of having toxoplasmosis infection. IHAT and DT titer > or = 4 and CFT > or = 5 were considered positive. Titers were classified as follows: low (4-16), median (64-512) and high (> or = 1000) for IHAT and DT. The pathologies for demanding these serological tests were: adenopathies (58), nephropathies (72), neuropathies (30), obstetrical problems (65), opthalmopathies (147), AIDS (237) and miscellaneous (37). Global positivity of 49.5% and 4.5% for IHAT/DT and CFT respectively were found. The positivity for the different groups were: adenopathies (48.3% and 13.8%), nephropathies (43.1% and 1.4%), neuropathies (26.7% and 3.3%), obstetrical problems (40.0% and 0.0%), ophthalmopathies (59.9% and 8.2%), AIDS (52.1% and 2.5%) and miscellaneous (40.5% and 2.7%) for IHAT/DT and CFT respectively. Low and median titers for IHAT/DT were found in 81.3% of cases. A high agreement in frequency of concordant and discordant titers of IHAT/DT and CFT, indicating a recent or acute infection was observed. This fact was more relevant in adenopathies, ophthalmopathies (uveitis) and AIDS groups.

Adolescent↗
PubMedDate not supplied

[Human infection by Trypanosoma cruzi in Chile: epidemiology estimates and costs of care and treatment of the chagasic patient].

According to the gathered information from the 1992 Chile census and an extensive epidemiological field study of Chagas' disease in rural-periurban sections of the seven most northern regions where this malady is endemic, the following epidemiological outline arises: Total population in the country 13,348,401. Population in endemic regions 8,824,205 (urban 8,050,700, rural 773,505). Number of infected 142,000 (16.7%). Total number of cardiopathies 26,554 (18.7%). In considering the regime of fees for health attentions of the National Health Funds--including hospitalization, laboratory tests and surgical interventions--in its minimal prices plus the value of medicaments, it is possible to produce some estimates on the cost of attention and treatment, in U.S. dollars, of the chagasic patient. Average annual cost of a patient with chronic chagasic cardiopathy U.S. $439.29 to U.S. $584.25 If these values are multiplied by 26,554 give rise to a figure ranging from U.S. $11,644,906 to U.S. $15,514,474.

Chagas Disease↗
PubMedDate not supplied

[Yield of xenodiagnosis and PCR in the evaluation of specific chemotherapy of Chagas' disease in children].

Amplification by the polymerase chain reaction (PCR) of Trypanosoma cruzi kinetoplastic DNA was used to enhance sensitivity in the detection of the parasite in blood, with the ultimate goal of improving the parasitological diagnosis of Chagas' disease in 0-10 year-old infected children. Twenty eight children were evaluated by using xenodiagnosis (XD) and PCR. Whereas XD detected 75.0% of the cases PCR was positive in 96.8%. The usefulness of the PCR was further investigated in the 28 children who have received specific treatment with nifurtimox. Negativation of XD after three and six months post treatment was observed in all the cases, but only 21.4% and 35.8% negativation of the PCR after three and six months post treatment respectively. These observations suggest that PCR is the most sensitive and quick technique available for direct detection of T. cruzi in chagasic children and that it can be a very useful tool for the follow-up of infected subjects after specific chemotherapeutical treatment.

Chagas Disease↗
PubMedDate not supplied

[Scorpion stings outbreaks in recently constructed urban dwellings inhabitants].

Scorpion stings are unfrequent in Chile. Most of cases occur in rural areas during the warm season. Clinical manifestations have a low to moderate intensity and consist in local pain and inflammation, sometimes associated with headache and hyperthermia. Two autbreaks of scorpion stings--affecting six and five adult residents (18-42 years old) of recently built urban dwelling complexes--have been recorded in Chile in summertime of 1957 and 1998. The first took place in the town of Maipú and the second in Villa Alborada sites respectively 10 and 150 km South of the city of Santiago. The Maipú dwelling complex was constituted by 112 one story houses in which lived 504 people. In Villa Alborada live 1,050 persons distributed in 158 apartments, 86 of which are in the main floor and in 26 of these last the occupants have observed scorpions inside. All the 11 cases occurred into the dwelling: four when sleeping at night, three performing different activities (trying to find a tool, searching a kee, housekeeping), two when putting their shoes, and two walking with bare feet in dormitory. In all the cases the causative scorpion was observed, captured or destroyed. Identification of six specimens from Maipú corresponded to Brachistoternus ehrenbergi and of two from Villa Alborada to Bothriurus borrelianus. All the patients presented mild to moderate symptomatology. Treatment consisted basically in oral antihistamanic and/or antinflammatory tablets. Recovery was observed within one to seven days with a mean of three days. Prophylactic measures consisted in health education and physical destruction of scorpions in Maipú and insecticide spraying on floors of basement apartments and surrounding areas in Villa Alborada. Though the majority of accidents by scorpion stings happens in rural areas, also may occur in urban areas--rural in the near past--where dwellings have been constructed in fields which in not to much preterit times constituted the habitat of the referred arthropod, phenomenom that have occurred in summertime in the two dwelling complexes described in the present communication.

Adolescent↗