Impact of involving the community in entomological surveillance of Triatoma infestans (Klug, 1834) (Hemiptera, Triatominae) vectorial control.

BACKGROUND: Vectorial transmission is the principal path of infection by Trypanosoma cruzi, the parasite that causes Chagas disease. In Argentina, Triatoma infestans is the principal vector; therefore, vector control is the main strategy for the prevention of this illness. The Provincial Program of Chagas La Rioja (PPCHLR) carries out entomological evaluation of domiciliary units (DUs) and spraying of those where T. infestans is found. The lack of government funds has led to low visitation frequency by the PPCHLR, especially in areas with a low infestation rate, which are not prioritized. Therefore, seeking possible alternatives to complement control activities is necessary. Involving householders in entomological evaluation could be a control alternative. The major objective was to determine the cost of entomological evaluation with and without community participation. METHODS: For entomological evaluation without community participation, PPCHLR data collected in February 2017 over 359 DUs of the Castro Barros Department (CBD) were used. For entomological evaluation with community participation, 434 DUs of the same department were selected in November 2017. Each householder was trained in collecting insects, which were kept in labeled plastic bags, recovered after 2 weeks, and analyzed in the laboratory for the presence of T. cruzi. Using householders' collection data, a spatial scan statistic was used to detect clusters of different T. infestans infestations. Entomological evaluation costs with and without community participation related to the numbers of DUs visited, DUs evaluated, and DUs sprayed were calculated and compared between methodologies. In addition, the number of DUs evaluated of the DUs visited was compared. RESULTS: According to the results, the triatomines did not show evidence of T. cruzi infection. Spatial analysis detected heterogeneity of T. infestans infestation in the area. Costs related to the DUs visited, evaluated, and sprayed were lower with community participation (p < 0.05). In addition, more DUs were evaluated in relation to those visited and a greater surface area was covered with community participation. CONCLUSION: Participation of the community in the infestation survey is an efficient complement to vertical control, allowing the spraying to be focused on infested houses and thus reducing the PPCHLR's costs and intervention times.

Phenotypic diversity of Triatoma infestans at the microgeographic level in the Gran Chaco of Argentina and the Andean valleys of Bolivia.

Triatoma infestans (Klug) is the main vector of Trypanosoma cruzi, etiologic agent of Chagas disease. The phenotype of the species varies at different geographic scales. The objective of this study was to compare the antennal phenotype of spatially close T. infestans populations and to evaluate its usefulness as a marker of exchange of individuals between populations. The antennal phenotype of 190 T. infestans from Argentina and Bolivia was analyzed using uni- and multivariate techniques. This study shows heterogeneity of the antennal phenotypes of closely related T. infestans populations living in different habitats. Specimens collected in a goat corral and a rabbit cage in La Rioja (Argentina) were dissimilar to the specimens collected in the nearby intradomestic environment. Similarly, specimens from peridomestic corrals in Cochabamba (Bolivia) were different from the intradomestic and sylvatic specimens, indicating some degree of isolation between these populations. In contrast, T. infestans collected in chicken coops and the intradomestic environment were similar, in all studied regions, suggesting a frequent exchange of individuals between the two habitats and/or because of the similarity of the habitat due to the presence of chickens in the intradomestic environment. We propose that each habitat affects in a particular mode the insect morphology and these changes could be used to identify recolonizing T. infestans. These results support the hypothesis of different degrees of isolation between intradomestic and peridomestic habitats. Within this context, special attention should be given to chicken coops and other close peridomestic structures in relation to the recolonization process of domestic habitats by T. infestans.

Infestation of rural houses by Triatoma infestans in the region of Los Llanos (La Rioja, Argentina).

Vectorial transmission of Chagas disease has been strongly reduced in most parts of the Southern Cone countries of South America, except in the Gran Chaco region of Argentina, Bolivia, and Paraguay. Given periodical interruptions of the vector control programmes in the endemic region of the Gran Chaco of Argentina, the vectorial transmission of the disease has been increasing during the last years. From the beginning of 2004, the provincial Ministry of Health of La Rioja, Argentina, started a vector control programme to cover the rural houses of the Los Llanos area in the southwestern area of the Gran Chaco region. This article reports the result of a standardized entomological survey and insecticide application against Chagas disease vectors in the intra and peridomestic structures of the rural houses of Los Llanos. A total of 4062 houses were inspected, of which 46.8% were found to be infested by Triatoma infestans. Infestation by vector species other than T. infestans was less than 0.5%(T. eratyrusiformis and T. platensis). Intradomestic infestation was found in 27.2%, whereas peridomestic infestation was found in 39.3% of the houses. The lowest figure of intradomestic infestation was 6.6% (Department F Varela), and the highest value of intradomestic infestation was 45.1% (Department Independencia). In spite of the demonstrated success of vector control elsewhere, this study shows that the vector populations are susceptible to pyrethroid insecticides in the southern area of the Gran Chaco of Argentina, that there still are regions where rural houses show heavy infestation by T. infestans associated with big peridomestic structures and that the vectorial transmission of the Chagas disease will continue, unless a sustained and well organized vector control effort is installed in the region.

Infestation of rural houses by Triatoma infestans in the region of Los Llanos (La Rioja, Argentina)

Vectorial transmission of Chagas disease has been strongly reduced in most parts of the Southern Cone countries of South America, except in the Gran Chaco region of Argentina, Bolivia, and Paraguay. Given periodical interruptions of the vector control programmes in the endemic region of the Gran Chaco of Argentina, the vectorial transmission of the disease has been increasing during the last years. From the beginning of 2004, the provincial Ministry of Health of La Rioja, Argentina, started a vector control programme to cover the rural houses of the Los Llanos area in the southwestern area of the Gran Chaco region. This article reports the result of a standardized entomological survey and insecticide application against Chagas disease vectors in the intra and peridomestic structures of the rural houses of Los Llanos. A total of 4062 houses were inspected, of which 46.8 percent were found to be infested by Triatoma infestans. Infestation by vector species other than T. infestans was less than 0.5 percent(T. eratyrusiformis and T. platensis). Intradomestic infestation was found in 27.2 percent, whereas peridomestic infestation was found in 39.3 percent of the houses. The lowest figure of intradomestic infestation was 6.6 percent (Department F Varela), and the highest value of intradomestic infestation was 45.1 percent (Department Independencia). In spite of the demonstrated success of vector control elsewhere, this study shows that the vector populations are susceptible to pyrethroid insecticides in the southern area of the Gran Chaco of Argentina, that there still are regions where rural houses show heavy infestation by T. infestans associated with big peridomestic structures and that the vectorial transmission of the Chagas disease will continue, unless a sustained and well organized vector control effort is installed in the region.

Efficacy and tolerability of celecoxib compared with diclofenac slow release in the treatment of acute ankle sprain in an Asian population.

INTRODUCTION: Cyclooxygenase (COX)-2 selective inhibitors are attractive candidates for treatment of ankle sprain because of their efficacy as anti-inflammatory and analgesic agents and their overall safety, including lack of effect on platelet aggregation. The objective of this study was to assess the efficacy and tolerability of celecoxib compared with diclofenac slow release (SR) in the treatment of acute ankle sprain in an Asian population. METHODS: In this seven-day, multicentre, double-blind, randomised, parallel-group trial, 370 patients with first- or second-degree ankle sprain occurring at or less than 48 hours prior to the first dose of study medication were randomised to receive celecoxib 200 mg bid (189 patients) after a 400 mg loading dose or diclofenac SR 75 mg bid (181 patients). Patients were required to demonstrate moderate to severe ankle pain on weight bearing (45 mm or greater on a 100 mm visual analogue scale [VAS]) at baseline. The primary efficacy end point was the patient's assessment of ankle pain (VAS on full weight bearing) on day 4. RESULTS: Celecoxib was as effective as diclofenac SR in improving the signs and symptoms of ankle sprain. At day 4, mean VAS scores for celecoxib and diclofenac SR had decreased to 28 mm and 30 mm, respectively. Treatment differences were not statistically significant. Incidence of upper gastrointestinal adverse events was low in both treatment groups (0.5 percent versus 2.2 percent for celecoxib and diclofenac SR, respectively). CONCLUSION: Celecoxib, a COX-2 selective inhibitor, is as effective as diclofenac SR in treating ankle sprains. With its platelet-sparing properties, celecoxib may offer an advantage over diclofenac SR in managing musculoskeletal injuries.

External pelvic fixation in an infant: a case report.

We report on the use of a small-frame Hoffman external fixator on an 18-month-old, 25-pound infant with a severe complex pelvic fracture and prostatic and urethral injury. The small-frame external fixator was found to be adequate in stabilizing the pelvis and maintaining hemodynamic control.

Genu recurvatum: a complication of prolonged femoral skeletal traction.

Genu recurvatum is a rare complication of prolonged skeletal traction. The literature reports very few cases, the majority secondary to wire traction applied to the tibia in the treatment of femoral shaft fractures. A case of genu recurvatum in a 12-year-old girl as a complication of prolonged femoral skeletal traction was treated at the Kobe University Hospital. A proximal open wedge tibial osteotomy using iliac bone grafts was the surgical treatment initiated at the time of diagnosis. Follow-up after 1 year showed recurrence of the genu recurvatum. Early surgical intervention, prolonged casting and application of knee orthosis were all contributory factors in the recurrence of genu recurvatum in our patient. It should be emphasized that extreme care should be taken in treating femoral shaft fractures in children, especially those requiring wire traction in the tibia or femur, in order to prevent genu recurvatum.