Tuberculosis contact tracing, Angola.

Objective: To assess the outcomes of a contact-tracing programme to increase the diagnosis of tuberculosis in Cubal, Angola and offer preventive treatment to high-risk groups. Methods: A health centre-based contact-tracing programme was launched in Hospital Nossa Senhora da Paz in March 2015 and we followed the programme until 2022. In that time, staffing and testing varied which we categorized as four periods: medical staff reinforcement, 2015-2017, with a doctor seconded from Vall d'Hebron University Hospital, Spain; routine staff, 2017-2021, with no external medical support; community directly observed treatment (DOT), 2018-2019 with community worker support; and enhanced contact tracing, 2021-2022, with funding that allowed free chest radiographs, molecular and gastric aspirate testing. We assessed differences in contacts seen each month, and testing and treatment offered across the four periods. Findings: Overall, the programme evaluated 1978 contacts from 969 index cases. Participation in the programme was low, although it increased significantly during the community DOT period. Only 16.6% (329/1978) of contacts had a chest radiograph. Microbiological confirmation increased to 72.2% (26/36) after including molecular testing, and 10.1% (200/1978) of contacts received treatment for tuberculosis. Of 457 contacts younger than 5 years, 36 (7.9%) received preventive tuberculosis treatment. Half of the contacts were lost to follow-up before a final decision was taken on treatment. Conclusion: Contact tracing increased the diagnosis of tuberculosis although engagement with the programme was low and loss to follow-up was high. Participation increased during community DOT. Community-based screening should be explored to improve participation and diagnosis.

Telemedicine experience between two hospitals from Angola and Spain.

OBJECTIVE: Telemedicine uses information and communication technologies to provide services in the field where the distance is a critical factor. The aim of the present study is to describe the experience of a synchronous telemedicine between two hospitals in Spain and Angola. METHODS: This is a retrospective observational study of all synchronous telemedicine sessions conducted between the Hospital Nossa Senhora da Paz in Angola and the Vall d'Hebron University Hospital in Spain from January 2011 to December 2014. RESULTS: Seventy-two cases were discussed in the telemedicine sessions. The average age of patients was 18.02 (SD 13.75) years and mostly women (54.38 percent). Reasons to discuss the cases were 46.47 percent doubts in the diagnosis and therapeutic management, 15.47 percent were purely formative cases, and only 8.45 percent treatment doubt. At the time of presentation, 29 percent of the patients were already diagnosed, 95 percent of whom with infectious disease diagnostic, and from the undiagnosed patients 36 percent presented a febrile syndrome. CONCLUSION: This study shows the viability of synchronous telemedicine between European and African countries without an excessively sophisticated technology.

Ultrasound findings and associated factors to morbidity in Schistosoma haematobium infection in a highly endemic setting.

OBJECTIVE: To evaluate the usefulness of the WHO classification of ultrasound pathological changes and to establish risk factors for morbidity in a highly endemic setting. METHODS: One hundred and fifty-seven ultrasounds were performed on school-aged children previously diagnosed with urinary schistosomiasis in Cubal, Angola. The findings were analysed according to the WHO guidelines. Factors for morbidity were studied. RESULTS: Mean age of the children was 8.7 (SD 3.2) years. Pathological changes were found in 85.3% (84.7% in the bladder, 34.4% the ureter and 6.3% kidney lesions). The global score according to the WHO classification was 5.74. Male gender [OR 2.61 (1.04-6.58); P 0.043] and older age [OR 2.96 (1.17-7.46); P 0.023] were associated with a higher risk of developing any kind of urinary abnormality. Proteinuria was present in 61.7% of the children. Macroscopic haematuria [OR 2.48 (1.11-5.58); P = 0.02)] and a high level of proteinuria > 300 mg/dl [OR 5.70 (2.17-14.94); P 300 mg/dl)] were associated with abnormalities of the upper urinary tract and showed good positive and negative predictive values for the detection of pathology in the upper urinary tract (65.5% and 71.1%, respectively). CONCLUSIONS: Severe urinary tract pathology was found in a high percentage of the children in our setting. Microhaematuria and proteinuria were good markers of morbidity, proteinuria being more precise for severe alterations of the upper urinary tract. We suggest initial and evolutive ultrasound in children diagnosed with schistosomiasis, and close monitoring including periodic controls. As schistosomiasis control efforts are currently focused on reducing morbidity, tests that detect the presence or degree of morbidity are essential for targeting treatment and tracking the progress of control campaigns.

Field and laboratory comparative evaluation of a LAMP assay for the diagnosis of urogenital schistosomiasis in Cubal, Central Angola.

OBJECTIVE: To evaluate the performance of Rapid-Heat LAMPellet assay in field conditions for diagnosis of urogenital schistosomiasis in an endemic area in Cubal, Angola, and to assess the reproducibility in a reference laboratory. METHODS: A total of 172 urine samples from school-age children were tested for microhaematuria, microscopic detection of Schistosoma haematobium eggs and LAMP for DNA detection. Urine samples were stored in a basic equipped laboratory. Field-LAMP tests were performed with and without prior DNA extraction from urine samples, and the results were read by turbidity and by colour change. When field procedures were finished, samples were sent to a reference laboratory to be reanalysed by LAMP. RESULTS: A total of 83 of 172 (48.3%) were positive for microhaematuria, 87/172 (50.6%) were microscopy-positive for S. haematobium eggs detection, and 127/172 (73.8%) showed LAMP-positive results for detecting S. haematobium using purified DNA and 109/172 (63.4%) without prior DNA extraction. MacNemar's test showed a statistical significant relation between LAMP results and microscopy-detected S. haematobium infections and microhaematuria (P < 0.001 in both cases), respectively. When samples of purified DNA were reanalysed in a reference laboratory in Spain using the same LAMP methodology, the overall reproducibility achieved 72.1%. CONCLUSIONS: The ease of use, simplicity and feasibility demonstrated by LAMP assay in field conditions together with the acceptable level of reproducibility achieved in a reference laboratory support the use of LAMP assay as an effective test for molecular diagnosis of urogenital schistosomiasis in endemic remote areas.

Changes in malaria epidemiology in a rural area of Cubal, Angola.

BACKGROUND: Scarce information about malaria epidemiology in Angola has been published. The objective of this study is to describe the epidemiology of malaria at the Hospital Nossa Senhora da Paz (Cubal, Angola) and the fatality rate due to malaria (total and in children under five years) in the last five years. METHODS: A retrospective, observational study was performed at the Hospital Nossa Senhora da Paz, a 400-bed rural hospital located in Benguela Province of Angola. The study population included all patients who attended the hospital from January 2009 to December 2013. Outcome variables were calculated as follows: the percentage of malaria cases (number of positive thick blood films, divided by the total thick blood films performed); the percentage of in-patients for malaria (number of in-patients diagnosed with malaria, divided by the total number of in-patients); and, the fatality rate (number of deaths due to malaria divided by the number of positive thick blood films). RESULTS: Overall, 23,106 thick blood films were performed, of which 3,279 (14.2%) were positive for Plasmodium falciparum infection. During this five-year period, a reduction of 40% (95% CI 37-43%, p < 0.001) in the malaria-positive slides was detected. Distribution of positive-malaria slides showed a seasonal distribution with a peak from December to March (rainy season). An average annual reduction of 52% (95% CI 50-54%, p < 0.001) in the admissions due to malaria was observed. The overall fatality rate due to malaria was 8.3%, and no significant differences in the annual fatality rate were found (p = 0.553). CONCLUSIONS: A reduction in the number of malaria cases and the number of admissions due to malaria has been observed at the Hospital Nossa Senhora da Paz, during the last five years, and incidence along the study period showed a seasonal distribution. All this information could be useful when deciding which malaria control strategies have to be implemented in this area.

Impact of traditional cutaneous scarification on anthrax lesions: A series of cases from Cubal, Angola.

OBJECTIVES: Bacillus anthracis infection is a worldwide zoonosis that affects the most vulnerable population and has a high mortality rate without treatment, especially in non-cutaneous presentations. Cutaneous scarification is still common in some regions of the world for the treatment of certain diseases as part of traditional medicine. We describe a series of cutaneus anthrax from a rural setting in Angola where cutaneus scarification is common. CASE PRESENTATION: This is a retrospective observational study describing a series of cutaneous anthrax cases from Cubal (Angola), many of whom were treated with skin scarification before admission. A total of 26 cases were diagnosed from January 2010 to December 2018. None of the cases were confirmed and eight (30.8%) were probable cases according to the Centers for the Disease Control and Prevention anthrax case definition. The median age was 11 (4.7-30.5) years, 17 (65.4%) had lesions on the head, face, or neck and 15 (57.7%) were treated with cutaneous scarification. Nine (34.6%) patients died. Traditional cutaneous scarification was significantly associated with cutaneous superinfection, respiratory, systemic involvement, and death. CONCLUSION: Our case series points to increased complications and worse outcome of cutaneous anthrax disease if treated with skin scarification.

Weather and electrical demand and consumption data of a small Mexican community.

The development of novel technologies to mitigate the effects of climate change through Smart Grids requires energy related data. Unfortunately, this type of data is not always available in Mexico, especially from non-large urban areas and at the household level. Therefore, we present a dataset that contains electrical demand and consumption time series of 5 households within a small community in Mexico, at various resolutions, as well as weather data. The electrical demand is given in 15 min resolution, while the electrical consumption is presented in both hourly and daily resolutions. The data is contained within 15 separate .csv files; one for each household's resolution. In turn, the weather data is given in two .csv files (for outdoor and indoor variables, respectively) that together contain 24 meteorological variables measured in a 5 min resolution that is not always consistent. The dataset comprises of two separate folders that contain either the electrical demand and consumption files or the weather files. This dataset could aid in the development of novel smart grid methods and algorithms that might be able to push the energy transition in Mexico and other developing countries forward.

Civil Engineering and Malaria Risk: A Descriptive Study in a Rural Area of Cubal, Angola.

(1) Background: Angola is among the high-burden countries with malaria cases globally. After 2013, we suspected an increase in the number of malaria cases in Cubal (Angola), previously in decline. Our objective was to evaluate the incidence rate in Cubal, overall and by neighborhood, for 2014, 2015, and 2016. (2) Methods: A retrospective, observational study was performed in Cubal (Angola) from January 2014 to December 2016, including all patients with a microbiologically confirmed diagnosis, treated at Cubal's Hospitals for this period of time. The principal variables calculated were the incidence rates of 2014, 2015, and 2016 in Cubal (overall and by neighborhood). (3) Results: There were 3249 malaria cases. The incidence rates were 2.27, 10.73, and 12.40 cases per 1000 inhabitants in 2014, 2015, and 2016, respectively. In the neighborhood, Hamavoko-Kasseke, there was a 10.73-fold increase in incidence during this period. Additionally, Hamavoko-Kasseke presents an anomalous distribution of malaria cases. (4) Conclusions: We observed an increase in the incidence of malaria in Cubal during the three-year study period. The case distribution was highly heterogeneous with hyperendemic areas, and we found a chronobiological association between the construction of a civil engineering project. This information could be useful for deciding which malaria control strategies must be implemented in this area.

Old zoonotic agents and novel variants of tick-borne microorganisms from Benguela (Angola), July 2017.

BACKGROUND: Ticks and tick-borne diseases constitute a real threat for the livestock industry, which is increasing in Angola. In addition, ticks are vectors of zoonoses of public health concern, and scarce information is available from this country. In an effort to contribute to the prevention of zoonotic infectious diseases affecting humans and animals, the molecular screening of certain tick-related microorganisms collected on cattle in Angola was performed under a 'One Health' scope. METHODS: Ticks collected from cattle in Cubal (Benguela Province, Angola) in July 2017 were analysed in pools using specific PCR assays for bacteria (Rickettsia, Anaplasmataceae, Borrelia, Coxiella and Spiroplasma) and protozoa (Theileria and Babesia) detection. RESULTS: A total of 124 tick specimens were grouped in 25 pools (two Amblyomma variegatum, three Hyalomma truncatum, 16 Rhipicephalus decoloratus, two Rhipicephalus duttoni, one Rhipicephalus evertsi mimeticus and one Rhipicephalus sp.). The amplified microorganisms were (pools): Rickettsia africae (two A. variegatum and one R. decoloratus), Rickettsia aeschlimannii (three H. truncatum), Ehrlichia spp. (six R. decoloratus), Coxiella spp. (all but H. truncatum), Francisella sp. (one H. truncatum), Spiroplasma sp. closely related to Spiroplasma ixodetis (three R. decoloratus), Babesia bigemina (two R. decoloratus) and Babesia spp. (two A. variegatum). The obtained nucleotide sequences from Ehrlichia spp., two Coxiella genotypes (from R. duttoni and Rhipicephalus sp.), Francisella sp. and Babesia spp. (from A. variegatum) reached low identities with known genetically characterized species. CONCLUSIONS: This study demonstrates the circulation in Angola of the pathogen R. aeschlimannii and potential novel tick-related microorganisms belonging to Ehrlichia, Coxiella, Francisella, Spiroplasma and Babesia spp. and corroborates the presence of R. africae and B. bigemina. Our results should be considered in developing protocols for the management of fever of unknown origin and for veterinary practices. Further studies are required to evaluate the risk of tick-borne diseases in Angola.

The complete mitochondrial genome of the strawberry aphid Chaetosiphon fragaefolii Cockerell, 1901 (Hemiptera: Aphididae) from California, USA.

The aphid Chaetosiphon fragaefolii Cockerell, 1901 is an agricultural pest and known vector of strawberry viruses. To better understand its biology and systematics, we performed a genomic analysis on C. fragaefolii collected from Quinalt strawberry plants from Pacific Grove, Monterey county, California, USA using Oxford Nanopore and Illumina sequencing. The resulting data were used to assemble the aphids complete mitogenome. The mitogenome of C. fragaefolii is 16,108 bp in length and contains 2 rRNA, 13 protein-coding, and 22 tRNA genes (GenBank accession number LC590896). The mitogenome is similar in content and organization to other Aphididae. Phylogenetic analysis of the C. fragaefolii mitogenome resolved it in a fully supported clade in the tribe Macrosiphini. Analysis of the cox1 barcode sequence of C. fragaefolii from California found exact and nearly identical sequences to C. fragaefolii and Chaetosiphon thomasi Hille Ris Lambers, 1953, suggesting the two species are conspecific.

Ultrasound Evolution of Pediatric Urinary Schistosomiasis after Treatment with Praziquantel in a Highly Endemic Area.

Urinary schistosomiasis causes damage to the urological system. Ultrasound is a method that detects the burden of secondary disease, individually and in epidemiological studies. In this study, the Schistosoma haematobium-associated urinary tract pathology is analyzed before and after treatment in a short period of time. Seventy children who had previously participated in an epidemiological study on schistosomiasis in the city of Cubal, Angola, and had also performed urinary ultrasound between August 2013 and February 2014 were cited 6-8 months later to assess the possible reinfection and repeat new urinary ultrasound, analyzing changes at the level of urinary pathology. The presence of hematuria and proteinuria was also analyzed. Of the 70 children analyzed, 29 (41.4%) were girls, with an average age of 10.4 years (standard deviation 2.3). Fifty-three (75.7%) had an improvement in their bladder and/or kidney scores, whereas 12 (17.1%) had no change and five (7.1%) had progression of the disease. None of the parameters analyzed completely disappeared. After one single course of treatment with praziquantel, all the analyzed parameters showed regression. Improvement was greater in the urinary bladder than in the upper urinary tract, though these lesions also reversed; the reversion of all parameters was greater among children older than 10 years old than the younger ones. Proteinuria was the parameter with a smaller reduction. Ultrasound should be a usual tool for diagnosis and follow-up in urinary schistosomiasis, particularly in children; more accurate recommendations about follow-up in the case of children whose lesions do not reverse should be established.

Prevalence and molecular characterization of Strongyloides stercoralis, Giardia duodenalis, Cryptosporidium spp., and Blastocystis spp. isolates in school children in Cubal, Western Angola.

BACKGROUND: Human infections by the gastrointestinal helminth Strongyloides stercoralis and the enteric protozoans Giardia duodenalis, Cryptosporidium spp. and Blastocystis spp. are not formally included in the list of 20 neglected tropical diseases prioritised by the World Health Organization. Although largely underdiagnosed and considered of lower public health relevance, these infections have been increasingly demonstrated to cause significant morbidity and even mortality globally, particularly among children living in resource-poor settings. METHODS: In this cross-sectional survey the prevalence, frequency and molecular diversity of S. stercoralis, G. duodenalis, Cryptosporidium spp. and Blastocystis spp. were investigated in a school children population in the province of Benguela (Angola). A total of 351 stool samples were collected during January to June 2015. The presence of S. stercoralis and G. duodenalis was confirmed by qPCR methods. Giardia duodenalis assemblages and sub-assemblages were determined by multilocus sequence-based genotyping of the glutamate dehydrogenase and ß-giardin genes of the parasite. Detection and identification of Cryptosporidium and Blastocystis species and subtypes was carried out by amplification and sequencing of a partial fragment of the small-subunit ribosomal RNA gene of both protozoan. Analyses of risk factors potentially associated with the transmission of these pathogens were also conducted. RESULTS: Prevalences of S. stercoralis, G. duodenalis, Cryptosporidium spp., and Blastocystis spp. were estimated at 21.4% (95% CI: 17.1-25.7%), 37.9% (95% CI: 32.8-43.0%), 2.9% (95% CI: 1.1-4.5%) and 25.6% (95% CI: 21.18-30.2%), respectively. Overall, 64.1% (225/351) of the children were infected by at least one of the pathogens investigated. Sequence analyses of the 28 G. duodenalis isolates that were successfully genotyped allowed the identification of sub-assemblages AI (14.3%), AII (14.3%), BIII (7.1%) and BIV (25.0%). Discordant typing results AII/AIII and BIII/BIV were identified in 7.1% and 14.3% of the isolates, respectively. A total of five additional isolates (17.9%) were identified as assemblage B. Three Cryptosporidium species including C. hominis (70%), C. parvum (20%) and C. canis (10%) were found circulating in the children population under study. A total of 75 Blastocystis isolates were assigned to the subtypes ST1 (30.7%), ST2 (30.7%), ST3 (36.0%), ST5 (1.3%) and ST7 (1.3%), respectively. Children younger than seven years of age had significantly higher risk of infections by protozoan enteropathogens (PRR: 1.35, P < 0.01), whereas being underweight seemed to have a protective effect against these infections (PRR: 0.74, P = 0.005). CONCLUSIONS: The burden of disease attributable to human strongyloidiasis, giardiosis, cryptosporidiosis and blastocystosis in Angola is considerably higher than initially estimated in previous surveys. Surveillance and control of these infections should be jointly tackled with formally considered neglected tropical diseases in order to maximize effort and available resources. Our data also demonstrate the added value of using molecular diagnostic methods in high transmission areas.

Prevalence of Strongyloides stercoralis and Other Intestinal Parasite Infections in School Children in a Rural Area of Angola: A Cross-Sectional Study.

Strongyloides stercoralis is widely distributed in the tropics and subtropics. The aim of this study was to determine the prevalence of S. stercoralis and other intestinal parasites and identify the risk factors for infection with S. stercoralis in a rural area of Angola. A cross-sectional study was conducted in school-age children (SAC) in Cubal, Angola. A questionnaire collecting clinical and epidemiological variables was used, and two stool samples were collected. A concentration technique (Ritchie) and a technique for detection of larvae migration (Baermann) were performed. Of 230 SAC, 56.1% were female and the mean age was 9.3 years (SD 2.45). Severe malnutrition, according to body mass index (BMI)-for-age, was observed in 20.4% of the SAC, and anemia was found in 59.6%. Strongyloides stercoralis was observed in 28 of the 230 (12.8%) SAC. Eggs of other helminths were observed in 51 (22.2%) students: Hymenolepis spp. in 27 students (11.7%), hookworm in 14 (6.1%), Schistosoma haematobium in four (1.7%), Enterobius vermicularis in four (1.7%), Ascaris lumbricoides in three (1.3%), Taenia spp. in two (0.9%), and Fasciola hepatica in one (0.4%). Protozoa were observed in 17 (7.4%) students. Detection of S. stercoralis was higher using the Baermann technique versus using formol-ether (11.3 vs. 3%). Overall prevalence of S. stercoralis in the school population of 16 studied schools in the municipal area of Cubal was greater than 10%. This fact must be considered when designing deworming mass campaigns. The use of specific tests in larvae detection is needed to avoid overlooking this parasite.

Oviposition preference and egg eclosion in different salt concentrations in the coastal malaria vector Anopheles aquasalis Curry.

Anopheles aquasalis is the main malaria vector in Sucre State, Venezuela. The larvae of this species are saltwater tolerant. The effects of different concentrations of salt on oviposition preference and egg survival were studied under laboratory conditions. Choice experiments with salt concentrations of 0, 10, 20, 30, and 40% in bottled water were set up for individual adult females and the number of eggs laid in each salt concentration was noted. Egg survival, as inferred by the number of hatched larvae also was determined for each salt concentration. Females preferred to oviposit in freshwater and rejected water salt concentrations of 40%, but they were neither attracted nor repelled by water with 10-30% of salt. Eggs hatched more quickly in the lower salt concentrations, but egg survival was not affected by salt concentrations of up to 20%. Thus, female oviposition preference in An. aquasalis determines egg survival.

Systematization of oral hygiene in a pediatric patient: case report / Sistematización de la higiene oral en un paciente pediátrico: reporte de caso

Oral hygiene is an important step in the control of the biofilm, a factor related to diseases such as gingivitis and tooth decay. The systematization of oral hygiene in children is a set of measures that seeks to achieve sequential learning, thus guaranteeing a better elimination of the biofilm. Objetive: To show a sequence of systematized steps in oral hygiene in a pediatric patient with a definitely positive behavior. Case Report: Six year old female patient, without relevant medical history. On clinical intraoral examination presented biofilm accumulation and swollen gums. The presumptive diagnosis was marginal gingivitis associated with biofilm, the treatment included a preventive phase with motivation and education. The control of the disease evolution was carried out with a card of Systematization Technique of Oral Hygiene, the methodology included the recording of the educational sessions using videos and photographs. Results: the adequate use of the amount of toothpaste was achieved, the integrity was improved to 100%, the brushing time increased from 24 to 120 seconds and it was possible to add tongue brushing and not rinsing after brushing within the oral hygiene routine. Conclusion: The patient was able to clean all dental surfaces, using homogeneous times for each surface, following an orderly sequence in toothbrushing, as well as to acquire knowledge regarding the amount of toothpaste to use, tongue brushing and not rinsing after toothbrushing. The systematization of oral hygiene allowed us to achieve these achievements in six sessions.

La higiene oral es un paso importante para el control de la biopelícula, la cual es un factor relacionado con enfermedades como gingivitis y caries dental. La sistematización de la higiene oral en niños es un conjunto de medidas que buscan lograr un aprendizaje secuencial, garantizando así una mejor eliminación del biofilm. Objetivo: Mostrar una secuencia de pasos sistematizados en la higiene oral en un paciente pediátrico con comportamiento definitivamente positivo. Reporte de un Caso: Paciente femenino de 6 años, sin antecedentes médicos relevantes. Al examen clínico intraoral presentó acumulación de biofilm y encías inflamadas. El diagnóstico presuntivo fue gingivitis marginal asociada a biofilm, el tratamiento incluyó una fase preventiva con motivación y educación. El control de la evolución se realizó con una ficha sobre la Técnica de Sistematización de Higiene oral, la metodología incluye el registro de las sesiones educativas usando vídeos y fotografías. Resultados: se logró el uso adecuado de la cantidad de dentífrico, se mejoró la integridad al 100%, el tiempo de cepillado pasó de 24 a 120 segundos y se consiguió integrar el cepillado de la lengua y el no enjuague post cepillado dentro de su higiene oral. Conclusión: La paciente consiguió realizar la limpieza de todas las superficies dentales, tiempos homogéneos para cada superficie, una secuencia ordenada en su cepillado dental, así como adquirir conocimientos en la cantidad de dentífrico utilizado, el cepillado de la lengua y el no enjuagarse después del cepillado dental. La sistematización de la higiene oral permitió conseguir estos logros en 6 sesiones.

Mycobacterium tuberculosis lineage 4 comprises globally distributed and geographically restricted sublineages.

Generalist and specialist species differ in the breadth of their ecological niches. Little is known about the niche width of obligate human pathogens. Here we analyzed a global collection of Mycobacterium tuberculosis lineage 4 clinical isolates, the most geographically widespread cause of human tuberculosis. We show that lineage 4 comprises globally distributed and geographically restricted sublineages, suggesting a distinction between generalists and specialists. Population genomic analyses showed that, whereas the majority of human T cell epitopes were conserved in all sublineages, the proportion of variable epitopes was higher in generalists. Our data further support a European origin for the most common generalist sublineage. Hence, the global success of lineage 4 reflects distinct strategies adopted by different sublineages and the influence of human migration.

Epidemiology of Schistosomiasis and Usefulness of Indirect Diagnostic Tests in School-Age Children in Cubal, Central Angola.

INTRODUCTION: Schistosomiasis remains a public health major problem and little is known in many areas, mainly in Sub-Saharan Africa. OBJECTIVES: To assess the burden and risk factors of schistosomiasis and intestinal parasitic helminthes in the children of Cubal, Angola, and to compare different diagnostic approaches for urinary schistosomiasis under field conditions. METHODS: A cross-sectional study was conducted. Urine and faeces samples of school children were microscopically studied. A random sample of children was obtained from an alphabetically arranged list of children, taking one of two children. Urine dipstick, colorimetric test and macrohaematuria were considered as indirect diagnostic methods and compared to direct urine examination. Possible risk factors for the infection were sex, age, distance to the river and previous treatment with praziquantel; the assessment was performed using Chi-square test. RESULTS: A total of 785 (61.18%) children showed S. haematobium eggs in urine; children living within 500 meters from the river had a higher odds for infection: Odds ratio 1.97 (1.45-2.7 CI 95%); urine dipstick showed sensitivity of 96% and specificity of 61.3%, with a positive predictive value; colorimetric test showed sensitivity of 52.5%, specificity of 74.6% and a positive predictive value of 77%. Proteinuria was present in 653 (51.1%) children, being more frequent in children with S. haematobium in urine (75.2%); 32 of 191 stool samples (16%) showed the presence of other intestinal parasites and 8 (4%) for S. haematobium. CONCLUSIONS: Prevalence of urinary schistosomiasis in our study area is much higher than the national average, considering it as a high-risk community. Proximity to a source of water was a risk factor for the infection. Indirect tests, as urine dipstick and colorimetric test, were useful tools for diagnosis, due to ease of use and low cost. Proteinuria was a common finding, probably showing an early structural damage due to schistosomiasis in this group of children.

Tuberculosis diagnosed in a rural setting in Angola. Accuracy of follow-up sputum smears to predict outcome.

OBJECTIVE: To analyze treatment outcome and the accuracy of positive sputum smear at 2 months to predict treatment failure in a cohort of patients with tuberculosis (TB) in a rural setting in Angola. DESIGN: Observational study of patients with TB from January 2009 to August 2010 in Hospital Nossa Senhora da Paz in Angola. A multivariate analysis was performed to identify variables associated with treatment failure and death. Sensitivity, specificity, positive and negative predictive values and likelihood ratios to define the accuracy of a positive sputum smear at 2 months to predict treatment failure were calculated. RESULTS: One thousand four hundred and twenty-five patients were diagnosed with TB. Overall, 526 patients were cured from TB and 419 had treatment completed, so 945 (66·3%) patients achieved treatment success. The outcomes of the remaining patients were: 91 (6·4%) had treatment failure, 100 (7%) died, 49 (3·4%) interrupted treatment, and 240 (16·8%) were transferred out. Variables associated with a higher risk of treatment failure were previously treated patients (odds ratio, 2·36; 95% confidence interval, 1·32-4·2) and positive sputum smear at 2 months (odds ratio, 9·81; 95% confidence interval, 5·88-16·36). Among the group of 551 patients with sputum smear confirmed at diagnosis and specimens taken at 2 and 5 months, the positive predictive value (31%) and the positive likelihood ratio (3·21) of a positive sputum smear taken at 2 months to predict treatment failure were low. CONCLUSIONS: Patients with positive sputum smear at 2 months have a higher risk of treatment failure. However, this by itself is a poor predictor of treatment failure.