ABSTRACT
No information has been yet published on snakebite in Bolivia. The country includes very different ecological situations leading to various epidemiological risks. A study has been carried out to evaluate the incidence and location of snakebite, particularly in relation with altitude, in order to improve management. Investigations on snakebite epidemiology were based on a) cases treated in health facilities as reported by health authorities and b) household surveys carried out in areas with high variations of altitude, in various regions of Bolivia. An average of 700 bites was treated each year in Bolivia (national annual incidence = 8 bites per 100,000 people) with a great disparity between districts. Household surveys showed annual incidences ranged from 30 to 110 bites per 100,000 inhabitants depending on location. Annual mortality ranged 0.1-3.9 per 100,000 people. A significant and constant inverse correlation was shown between snakebite incidence and altitude, which may be explained by both snake and human distributions and activities. Notification of snakebite is useful for improving patient management and informing antivenom distribution. It should also involve the report of deaths and clinical details of envenomation.
Subject(s)
Snake Bites/epidemiology , Snake Bites/mortality , Adult , Altitude , Bolivia/epidemiology , Female , Geography , Health Surveys , Humans , Incidence , Male , Middle Aged , Retrospective Studies , Rural Population , Seasons , Urban PopulationABSTRACT
OBJECTIVE: To compare the drop of Chagas antibody titres between non-infected and congenitally infected newborns treated by two doses of benznidazole, aiming at evaluating the recovery time and giving recommendations regarding serological criteria of recovery. METHODS: During a clinical trial, the drop of Trypanosoma cruzi antibody titres measured by ELISA tests was followed during the first year of life in congenitally infected newborns treated with different doses of benznidazole and compared to T. cruzi antibody titres in non-parasitaemic newborns. Confirmation of recovery was given by two negative serological tests: Chagas Stat-Pak (CSP) (immunochromatography) and Chagatest v3.0 (ELISA). RESULTS: In non-parasitaemic infants of infected mothers, antibodies of maternal origin disappeared in <8 months while in infected infants, T. cruzi antibodies decreased more slowly and disappeared in 9-16 months allowing to confirm the recovery. All CSP tests were negative before the ninth month while about 10% of ELISA tests remained positive at the 12th month. CONCLUSIONS: Recovery may be confirmed in most cases at 10 months. The CSP test was compared to Chagatest v3.0 ELISA and appeared to give a reliable response. The decrease rate of antibodies does not depend on treatment modes.
Subject(s)
Antibodies, Protozoan/blood , Chagas Disease/congenital , Nitroimidazoles/therapeutic use , Trypanocidal Agents/therapeutic use , Trypanosoma cruzi/immunology , Chagas Disease/drug therapy , Chagas Disease/immunology , Chagas Disease/transmission , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay/methods , Female , Follow-Up Studies , Humans , Infant, Newborn , Infectious Disease Transmission, Vertical , Nitroimidazoles/administration & dosage , Parasitemia/drug therapy , Parasitemia/immunology , Pregnancy , Pregnancy Complications, Infectious , Treatment Outcome , Trypanocidal Agents/administration & dosageABSTRACT
OBJECTIVE: To compare the results of an immunochromatographic test performed on whole blood, Chagas Stat-Pak, with those of an ELISA test using recombinant antigens. METHOD: We tested 995 subjects of a rural population of all ages in the south of Bolivia, 459 pregnant women of the same population and 1030 urban women giving birth from the east of Bolivia. RESULTS: The sensitivity of the CSP test for the entire studied population (n = 2484) was 94.73% [93.35-96.10]; the specificity was 97.33% [96.50-98.15]. However, the specificity differed significantly between rural pregnant and urban birthing women, which could be attributed either to differences of parasite strain or Chagas prevalence. CONCLUSION: The test is simple of use, reliable, relatively inexpensive (<2 US$ each test) and its performances are compatible with a field use for large-scale screenings.
Subject(s)
Chagas Disease/diagnosis , Reagent Kits, Diagnostic/standards , Trypanosoma cruzi/isolation & purification , Adolescent , Adult , Age Factors , Animals , Antigens, Protozoan/immunology , Bolivia/epidemiology , Chagas Disease/epidemiology , Chagas Disease/immunology , Child , Child, Preschool , Feasibility Studies , Female , Humans , Infant , Male , Middle Aged , Pregnancy , Prospective Studies , Sensitivity and Specificity , Trypanosoma cruzi/immunology , Young AdultABSTRACT
We evaluated the prevalence of Chagas disease using a rapid screening test (Chagas Stat-Pak), confirmed by ELISA, in Caraparí, a village of 9000 inhabitants in southern Bolivian Chaco. The prevalence of Trypanosoma cruzi was estimated in a sample of 995 people. The prevalence adjusted on age was 51.2% and was proportionally related to age. We also observed a very significant cline from the south to the north of the locality, where the prevalence ranged from 40 to 80%. In children younger than 11 years, the prevalence was 21.5%, which confirmed the importance of residual vector transmission despite several years of vector control. Among women of procreation age, the prevalence was 63.9%, resulting in a high risk of congenital transmission. The control of the disease requires an increase in vector control and improvement of dwellings before considering children's treatment with trypanocide.
