Introducción. Se publican pocos estudios sobre las causas del retardo del diagnóstico y el tratamiento de la malaria en Bolivia. Objetivo. Conocer los factores que retardan el diagnóstico y el tratamiento de la malaria en el servicio público del municipio de Riberalta, Bolivia. Materiales y métodos. Se calcularon los tiempos transcurridos entre el inicio de los síntomas y el tratamiento, entre el inicio de los síntomas y el diagnóstico, y entre el diagnóstico y el inicio del tratamiento; se compararon las medias de los tiempos calculados con el lugar de infección, la especie parasitaria, el nivel de atención, el lugar y el método de diagnóstico, y la edad se correlacionó con los tiempos calculados. Resultados. De 2.482 casos positivos válidos evaluados entre enero y diciembre de 2010, se encontró una media de 4,16 días entre el inicio de los síntomas y el inicio del tratamiento, de 4,07 días entre el inicio de los síntomas y el diagnóstico, y de 0,10 días entre el diagnóstico y el tratamiento. El retardo del diagnóstico y los factores, lugar de diagnóstico, lugar de infección, nivel de atención, especie parasitaria y método de diagnóstico, mostraron una diferencia estadística significativa (p<0,05). En el análisis de la covarianza se observó una asociación estadística con el nivel de atención y la especie parasitaria (p<0,05) Conclusión. Existe un retardo en el diagnóstico de la malaria, lo cual es influenciado por factores como el lugar de infección, lugar del diagnóstico, nivel de atención, especie parasitaria y método de diagnóstico.

Introduction. Few studies on the causes of the delay of malaria diagnosis and treatment in Bolivia are published. Objective. To know the factors that delay malaria diagnosis and treatment of malaria in the public service of the town of Riberalta, Bolivia. Materials and methods. The times between the onset of symptoms and treatment, between the onset of symptoms and diagnosis and between the diagnosis and the start of treatment were calculated. The averages of the calculated times were compared with respect to the site of infection, parasite species, level of care, place of diagnosis and diagnostic method and th patient’s age was correlated with the calculated times. Results. Between January and December 2010, 2,482 positive valid cases were studied. An average of 4.16 days was found between the onset of symptoms and the start of treatment, the average time between the onset of symptoms and diagnosis was 4.07 days, and between diagnosis and the start of treatment 0.10 days. Statistically significant (p<0.05) differences were found for factors related to the delay of diagnosis such as place of diagnosis, site of infection, level of care, parasite species and diagnostic method. The analysis of covariance showed a statistical association with the level of care and the parasite species (p<0.05). Conclusion. The delay in malaria diagnosis is influenced by factors such as the site of infection, place of diagnosis, level of care, parasite species and diagnostic method.

With AIDS/HIV, early detection is of key importance to public health, as well as disseminating prevention information and providing timely and appropriate treatment. In Bolivia, at the end of 2006 approximately 50% had AIDS at the time of diagnosis, detection having occurred late in the illness. The HIV/AIDS epidemic in Bolivia is concentrated, with prevalence rates over 5% among the atrisk population, primarily men who have sex with men. From January 1984 through October 2006, the total number of HIV/AIDS cases reported in Bolivia rose to 2 190, with 1 239 HIV and 951 AIDS cases, and underreporting estimated to be over 70% country-wide. The United National Joint Program on AIDS (UNAIDS) estimated that by the end of 2006 there would be 6 700 people living with HIV/AIDS in Bolivia. In the context of this scenario, the article describes the challenges facing the HIV/AIDS program and the strategies developed to address the epidemic in Bolivia. In addition, the UN-AIDS/PAHO strategies are stressed and must get underway for HIV/AIDS prevention and control activities in the country.

Based on the results of comparative analyses of 1,039 specimens of several progenies of Anopheles nuneztovarifrom three localities in Colombia, eight costal wing spot patterns were observed. Patterns I and III were the most frequent: 77.96% and 11.36%, respectively. Using the diagnostic characters ratio of the length of the basal dark area of hind tarsomere II/length of hind tarsomere II, ratio of the length of the humeral pale spot/length of the pre-humeral dark spot, and the ratio of the length of the subcostal pale spot/length of the distal sector dark spot (DS-III2/Ta-III2, HP/PHD, SCP/DSD) approximately 5% of the adult females were misidentified as a species of Nyssorhynchus, different from An. nuneztovari. Approximately 5% of the specimens showed DS-III2/Ta-III2 ratio less than 0.25 (range 0.21 - 0.24), and among them 3.34% shared a HP/PHD ratio less than 1.50. Consequently, 1.52% of An. nuneztovari individuals can be misidentified as Anopheles oswaldoi. In those specimens with the DS-III2/Ta-III2 ratios higher than 0.25, 34.45% displayed SCP/DSD values greater than 0.50 and of these, 3.65% displayed HP/PHD values greater than 1.8. This combination of characters could lead one to misidentify samples of An. nuneztovari as Anopheles rangeli. Similarly, 2.43% of the females could be identified erroneously as either Anopheles aquasalis or Anopheles benarrochi. Individuals with a HP/PHD ratio greater than 2.0, could be misidentified as Anopheles trinkae, Anopheles strodei or Anopheles evansae. A distinct combination of diagnostic characters for An. nuneztovari from Colombia is proposed.

Mediante muestreos larvales se evaluó la positividad y asociación poblacional del vector de dengue, Aedes aegypti, con Culex quinquefasciatus, vector del virus del Nilo, en 537 sumideros ubicados en 19 comunas de seis SILOS (Sistemas Locales de Salud) de la Ciudad de Cali, Colombia. Los índices promedio de positividad de sumideros (IS) fueron 57,2 y 73,6% para cada especie, respectivamente. Aunque sólo fue una tendencia, estos valores variaron acorde al estrato social de la ciudad y en todas las áreas evaluadas se estableció que ambas especies presentan una asociación poblacional positiva de alta significancia. Al evaluar la importancia relativa de los sumideros en la producción de A. aegypti, se observó que estos criaderos son tan o más importantes que los encontrados en áreas intra y peridomiciliares de los barrios y unidades residenciales. El análisis de las casas de 10 manzanas, incluyendo 62 sumideros ubicados en la vecindad próxima de las viviendas, mostró que en el intradomicilio no se producen pupas. Si se asume una tasa constante de sobrevivencia diaria de 0,80, el número de hembras/manzana estimado para los sumideros fue mayor que la de otros criaderos del peridomicilio. Para los sumideros la densidad absoluta varió entre 45 y 555 (= 200 hembras/manzana), mientras que en los segundos, éste varió únicamente entre 0 y 69 ( = 22 hembras/manzana).

Larval sampling was carried out to evaluate the presence and population relationship between the vector of dengue, Aedes aegypti and Culex quinquefasciatus, vector of West Nile virus, in 537 sinks, located in 19 “comunas” (quarter associations) of the six SILOS (i.e. local health systems) of the city of Cali, Colombia. The mean positivity index (IS) for the sinks was 57.2% and 73.6% for each species, respectively. Although it was only a tendency, these values varied according to city social strata, and in all of the areas evaluated it was established that each species had a highly significant positive population correlation. In evaluating the relative importance of the city sinks in the production of A. aegypti, it was established that those breeding sites are equally or more important than intra or peridomiciliar breeding sites. The analysis of houses in 10 city blocks, including 62 street sinks in the nearby vicinity, revealed that intradomiciliar settings do not produce pupae. Assuming a constant adult survival rate of 0.80 per day, the number of females per block estimated for the sinks was greater than peridomiciliar breeding sites. For the street sinks, absolute density varied between 45 and 555 ( 200 female/block), while in the peridomiciliar settings it was only 0 and 69 ( 22 female/block).

The genetic variation and population structure of three populations of Anopheles darlingi from Colombia were studied using random amplified polymorphic markers (RAPDs) and amplified fragment length polymorphism markers (AFLPs). Six RAPD primers produced 46 polymorphic fragments, while two AFLP primer combinations produced 197 polymorphic fragments from 71 DNA samples. Both of the evaluated genetic markers showed the presence of gene flow, suggesting that Colombian An. darlingi populations are in panmixia. Average genetic diversity, estimated from observed heterozygosity, was 0.374 (RAPD) and 0.309 (AFLP). RAPD and AFLP markers showed little evidence of geographic separation between eastern and western populations; however, the F ST values showed high gene flow between the two western populations (RAPD: F ST = 0.029; Nm: 8.5; AFLP: F ST = 0.051; Nm: 4.7). According to molecular variance analysis (AMOVA), the genetic distance between populations was significant (RAPD:phiST = 0.084; AFLP:phiST = 0.229, P < 0.001). The F ST distances and AMOVAs using AFLP loci support the differentiation of the Guyana biogeographic province population from those of the Chocó-Magdalena. In this last region, Chocó and Córdoba populations showed the highest genetic flow.

En la búsqueda de alternativas de control de Aedes aegypti, vector del dengue, se evaluó una formulación en pastillas de Bacillus thuringiensis israeliensis (BTI) en recipientes para almacenar agua. En Cali se seleccionaron tres zonas a intervenir, zona urbana Jarillón de Floralia, zona rural Montebello y Brisas de Montebello. En estos sitios se trataron 101 depósitos entre tanques y barriles metálicos, tomando 20 recipientes como grupo testigo. En los recipientes se contó el número de larvas; con un cucharón de aproximadamente 500 ce de capacidad, antes de la aplicación se tomaron cuatro muestras por recipiente, se empleó una pastilla de BTI por cada 50L de agua, se efectuaron evaluaciones postratamiento a los 15, 30 y 40 días; con los datos obtenidos se halló el porcentaje de reducción de Aedes aegypti. Igualmente se evaluaron las pastillas con la participación de la comunidad; se trataron 49 depósitos entre tanques y barriles metálicos, tomando 11 recipientes como grupo testigo, los recipientes se marcaron cada 50L, indicando el número de pastillas a aplicar de acuerdo con el nivel de agua en cada recipiente. A las personas que participaron en el estudio se les suministraron pastillas para 2 tratamientos, se realizaron evaluaciones postratamiento a los 20, 40, 60 y 80 días, las cuales fueron efectuadas de la misma forma descrita en la primera evaluación. El porcentaje de reducción en pupas obtenido en la evaluación a los 30 días fue del 100, 89 y 93% en el Jarillón de Floralia, Brisas de Montebello y Montebello respectivamente y de 90, 76 y 4% a los 45 días, para las mismas localidades. El porcentaje de reducción en pupas obtenido en la evaluación con participación comunitaria a los 40 días fue del 99 y 100%, en Brisas de Montebello y Montebello respectivamente y de 83 y 100% a los 80 días para las mismas localidades. Este último valor obtenido a los 80 días no está reflejando la residualidad de las pastillas, indica que la comunidad que participó en la intervención sí aplicó la segunda dosis suministrada desde el inicio del estudio. La formulación de BTI en pastillas es una herramienta para el control de Aedes aegypti en recipientes.

In the search of control alternatives for Aedes aegypti the mosquito vector of dengue fever, a formulation in pills of Bacillus thuringiensis israeliensis in containers to store water was evaluated. In Cali three zones were selected to intervene: urban zone Jarillón de Floraría (located on Cauca river's border), rural zone Montebello and Brisas de Montebello. In these sites 101 deposits between tanks and metallic barréis were treated, taking 20 containers as control group. The number of larvae in the containers was counted, with a ladle of approximately 500 ce. Before the application four samples by container were taken, a BTI pill for each 50 Lt of water was applied. Evaluations post-treatment were conducted at 15, 30 and 40 days; with the obtained data the percentage of larvae reduction was found. After this, the pills were evaluated with community participation, a total of 49 containers among tanks and metallic barréis were used, taking 11 containers as control group, the containers were marked each 50 Lt as indication of pills amount needed. For each house were given pills for two treatments; post-treatment evaluations were conducted at 20, 40, 60 and 80 days, the method described on the first evaluation was used. The pupae reduction percentage obtained on the evaluation at 30 days was 100, 89, and 93% in Jarillón de Floralia, Brisas de Montebello y Montebello respectively, and 90, 76, and 4% at 45 days for the same localities. The percentage of reduction in pupas obtained on the evaluation with the community at 40 days was 99 and 100% in Brisas de Montebello and Montebello respectively, and 83 and 100% at 80 days for the same localities. This last valué, obtained at 80 days, is not reflecting the pills residuality, which indicates that the community that participated in the intervention applied the second dose supplied since the start of the study. The BTI pills formulation is an efective tool Aedes aegypti control in water containers.

Random amplified polymorphic DNA (RAPD) markers were used to analyze 119 DNA samples of three Colombian Anopheles nuneztovari populations to study genetic variation and structure. Genetic diversity, estimated from heterozygosity, averaged 0.34. Genetic flow was greater between the two populations located in Western Colombia (F ST: 0.035; Nm: 6.8) but lower between these two and the northeastern population (F ST: 0.08; Nm: 2.8). According to molecular variance analysis, the genetic distance between populations was significant (phiST 0.1131, P < 0.001). The variation among individuals within populations (phiST 0.8869, P < 0.001)was also significant, suggesting a greater degree of population subdivision, not considered in this study. Both the parameters evaluated and the genetic flow suggest that Colombian An. nuneztovari populations are co-specific.