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1.
Clin Infect Dis ; 70(4): 574-580, 2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-30950493

RESUMEN

BACKGROUND: The mechanisms underlying the finding of reduced child mortality in communities with biannual treatment with azithromycin remain unclear. We determined if there was a difference in morbidity in a cohort of children aged 1-36 months, residing in communities randomized to biannual treatment of preschool-aged children with azithromycin or placebo. METHODS: Thirty villages in Kilosa, Tanzania, were randomly assigned to receive biannual treatment of all children aged 1-59 months with either azithromycin (20/mg/kg single dose) or placebo. Children who were aged 1-36 months and participated in the baseline survey were enrolled in this cohort study and followed prospectively for 2 years. Children were monitored every 6 months for signs and symptoms of diarrheal disease, acute respiratory illness, and anemia. Mixed-effects models that include age, time, treatment arm, and the interaction of treatment arm and time as independent predictors were used to evaluate differences between children by treatment assignment over time. RESULTS: There was no difference in rates of diarrhea, fever, or anemia by treatment arm at baseline and at all phases of follow-up. The decline over time in reported cough was statistically significant in the children residing in the azithromycin communities, but not in the placebo communities. Once adjusting for clustering and age, the difference in decline between the 2 treatment arms was not significant (P = .09). CONCLUSIONS: A beneficial effect of azithromycin treatment on morbidity outcomes was not evident at biannual surveys. CLINICAL TRIALS REGISTRATION: NCT02048007.


Asunto(s)
Azitromicina , Administración Masiva de Medicamentos , Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Niño , Preescolar , Estudios de Cohortes , Humanos , Lactante , Morbilidad , Prevalencia , Tanzanía/epidemiología
2.
J Viral Hepat ; 26(6): 750-756, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30712273

RESUMEN

Blood transfusion is one of the most commonly relied upon therapies in sub-Saharan Africa. Existing safeguards recommended include systematic screening for transfusion-transmitted infections and restricted voluntary nonremunerated blood donor selection. We report the transfusion-transmitted infection screening and notification practice at a large urban blood transfusion centre in Dar-es-Salaam, Tanzania. Between October 2016 and March 2017 anonymized records of all donors registered at the blood transfusion unit were accessed to retrospectively note demographic information, donor status, first-time status, transfusion-transmitted infection result and notification. 6402 consecutive donors were screened for transfusion-transmitted infections; the majority were family/replacement blood donors (88.0%) and male (83.8%). Overall transfusion-transmitted infections prevalence was 8.4% (95% CI 7.8-9.1), with hepatitis B being the most prevalent infection (4.1% (95% CI 3.6-4.6)). Transfusion-transmitted infections were more common in family/replacement blood donors (9.0% (95% CI 8.3-9.8)) as compared to voluntary nonremunerated blood donor (4.1% (95% CI 2.8-5.7)). A minority of infected-donors were notified of a positive result (8.5% (95% CI 6.3-11.2)). Although transfusion-transmitted infections are more prevalent among family/replacement blood donors, overall risk of transfusion-transmitted infections across all groups is considerable. In addition, existing efforts to notify donors of a positive transfusion-transmitted infection are poor. Future policies must focus on improving linkage to care for newly diagnosed patients with transfusion-transmitted infections.


Asunto(s)
Donantes de Sangre , Infecciones por VIH/epidemiología , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Reacción a la Transfusión/epidemiología , Reacción a la Transfusión/prevención & control , Adolescente , Adulto , Transfusión Sanguínea , Notificación de Enfermedades , Familia , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/diagnóstico , Hepatitis B/sangre , Hepatitis B/diagnóstico , Hepatitis C/sangre , Hepatitis C/diagnóstico , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Tanzanía/epidemiología , Reacción a la Transfusión/virología , Adulto Joven
3.
PLoS One ; 19(4): e0302076, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38625965

RESUMEN

BACKGROUND: Polymicrobial bloodstream infections (BSI) are difficult to treat since empiric antibiotics treatment are frequently less effective against multiple pathogens. The study aimed to compare outcomes in patients with polymicrobial and monomicrobial BSIs. METHODS: The study was a retrospective case-control design conducted at Muhimbili National Hospital for data processed between July 2021 and June 2022. Cases were patients with polymicrobial BSI, and controls had monomicrobial BSI. Each case was matched to three controls by age, admitting ward, and duration of admission. Logistic regression was performed to determine independent risk factors for in-hospital and 30-day mortality. RESULTS: Fifty patients with polymicrobial BSI and 150 with monomicrobial BSI were compared: the two arms had no significant differences in sex and comorbidities. The most frequent bacteria in polymicrobial BSI were Klebsiella pneumoniae 17% (17/100) and Enterobacter species 15% (15/100). In monomicrobial BSI, S. aureus 17.33% (26/150), Klebsiella pneumoniae 16.67% (25/150), and Acinetobacter species 15% (15/150) were more prevalent. Overall, isolates were frequently resistant to multiple antibiotics tested, and 52% (130/250) were multidrug resistance. The 30-day and in-hospital mortality were 33.5% (67/200) and 36% (72/200), respectively. On multivariable analysis, polymicrobial BSIs were independent risk factors for both in-hospital mortality (aOR 2.37, 95%CI 1.20-4.69, p = 0.01) and 30-day mortality (aOR 2.05, 95%CI 1.03-4.08), p = 0.04). In sub-analyses involving only neonates, polymicrobial BSI was an independent risk factor for both 30-day mortality (aOR 3.13, 95%CI 1.07-9.10, p = 0.04) and in-hospital mortality (aOR 5.08, 95%CI 1.60-16.14, p = 0.006). Overall, the median length of hospital stay post-BSIs was numerically longer in patients with polymicrobial BSIs. CONCLUSION: Overall, polymicrobial BSI was a significant risk for mortality. Patients with polymicrobial BSI stay longer at the hospital than those with monomicrobial BSI. These findings call for clinicians to be more aggressive in managing polymicrobial BSI.


Asunto(s)
Bacteriemia , Sepsis , Recién Nacido , Humanos , Estudios de Casos y Controles , Estudios Retrospectivos , Bacteriemia/microbiología , Tanzanía/epidemiología , Staphylococcus aureus , Sepsis/microbiología , Factores de Riesgo , Hospitales , Antibacterianos/uso terapéutico
4.
PLoS Negl Trop Dis ; 18(4): e0012090, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38598562

RESUMEN

BACKGROUND: The Alliance for the Global Elimination of Trachoma (GET) endorses the full SAFE strategy to eliminate trachoma; Surgery (for trichiasis), Antibiotics (to reduce the community pool of infection, Facial cleanliness, and Environmental improvement (to decrease transmission). There is no accepted measure of facial cleanliness. This study compared two possible metrics for facial cleanliness. METHOD/FINDINGS: Metric one: Clean face was defined as observed absence of ocular and nasal discharge on the face. Metric two: observing a grade of dirtiness (scale 10 = lightest to 0 = darkest) on a standard facial wipe. The reliability of grading a child's face or grading a facial wipe was determined in children in Kongwa Tanzania. We also observed both measurements in a cohort of 202 children ages 1 to <7years prior to face cleaning, immediately afterwards, and 4 hours afterwards. Fifty of the children did not have face cleaning and were controls. Intra-and interobserver reliability was similar for both measures, the latter = 0.53 for observing a clean face and 0.52 for grading a facial wipe. There was no correlation between the two. Both measures detected facial cleaning, compared to control children who were not cleaned, immediately after cleaning; control children with 53% clean faces and wipe score of 6.7 compared to cleaned children with 88% clean faces and wipe score of 8 (p = .0001, p = < .0001, respectively). Both measures also detected face washing 4 hours previously compared to controls. CONCLUSIONS: The two metrics were equally reliable, and both measured the behavior of face washing. They measure different aspects of a clean face; one measures the amount of dirt on wiped area and the other measures ocular and nasal discharge. Both measurements appear to capture the behavior of facial cleaning, and the choice of metric would appear to rest on the measurement that captures the stated objective of the behavior, consideration of costs, training, logistics, and implementation.


Asunto(s)
Cara , Higiene , Tracoma , Humanos , Tracoma/prevención & control , Preescolar , Tanzanía/epidemiología , Lactante , Femenino , Masculino , Niño , Higiene/normas , Reproducibilidad de los Resultados
5.
Adv Hematol ; 2024: 1937419, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38524403

RESUMEN

Introduction: Due to the significant resources involved in creating HSCT programs there is a significant disparity in the availability of this treatment modality between the developed and developing countries. This manuscript details the process and the outcomes of the first HSCT program in East Africa which was started at Muhimbili National Hospital (MNH) in Dar-es-Salaam, Tanzania. Materials and Methods: Information and data were collected on the processes which had been implemented for starting the HSCT program at MNH. The details of the collaborations, training, infrastructure development, and acquisition of the biomedical equipment, as well as the actual process for HSCT, as well as the outcomes of treatment are described. Observations. The project has been detailed in 4 stages for ease of description: Stage 1: Preparatory work which was performed by the Government of Tanzania, as well as the administrators and clinicians from MNH (July 2017-September 2021). Stage 2: Exploratory gap analysis by the teams from MNH and International Haematology Consortium of HCG Hospital, India (HCG-IHC) in October 2021. Stage 3: Activities for closure of gaps (November 2021). Stage 4: Stem Cell Transplantation Camps (November 2021 to March 2022). 11 peripheral blood stem cell transplants were done in two camps, November 2021 (5 patients), and February 2022 (6 patients). 10 patients underwent autologous peripheral blood stem cell transplantation for multiple myeloma and 1 for lymphoma. The median duration of hospital stay was 19 ± 6 days. The median time for neutrophil engraftment, it was on 8.8 ± 0.8 days, and for platelet engraftment was 9.6 ± 2.4 days. Progression-free survival was 100%, and there was no mortality. Conclusion: Commonalities in the socioeconomic challenges in developing countries can be leveraged to create robust HSCT programs in other developing countries.

6.
Vaccines (Basel) ; 12(1)2023 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-38250835

RESUMEN

COVID-19 vaccination remains to be the most important intervention in the fight against the pandemic. The immunity among the vaccinated population and its durability can significantly vary due to various factors. This study investigated the humoral immune responses among individuals who received any of the COVID-19 vaccines approved for use in Tanzania. A total of 1048 randomly selected adults who received COVID-19 vaccines at different time points were enrolled and humoral immune responses (IR) were tested at baseline and three months later (960, 91.6%). The level of SARS-CoV-2 anti-spike/receptor binding domain (RBD) IgG, anti-nucleocapsid IgG, and IgM antibodies were determined using a commercially available chemiluminescent microparticle immunoassay. Descriptive data analysis was performed using STATA version 18 and R. At baseline, serum IgG against anti-spike/RBD was detected in 1010/1048 (96.4%) participants (95%CI: 94.9-97.5) and 98.3% (95%CI: 97.3-99) three months later. The IgG against the SARS-CoV-2 nucleocapsid proteins were detected in 40.8% and 45.3% of participants at baseline and follow-up, respectively. The proportion of seroconverters following vaccination and mean titers of anti-spike/RBD antibodies were significantly more among those who had past SARS-CoV-2 infection than in those with no evidence of past infection, (p < 0.001). Only 0.5% of those who had detectable anti-spike/RBD antibodies at baseline were negative after three months of follow-up and 1.5% had breakthrough infections. The majority of participants (99.5%) had detectable anti-spike/RBD antibodies beyond 6 months post-vaccination. The proportion of Tanzanians who mounted humoral IR following COVID-19 vaccination was very high. Seroconversions, as well as the mean titers and durability of humoral IR, were significantly enhanced by exposure to natural SARS-CoV-2 infection. In view of the limited availability of COVID-19 vaccines as well as challenges to completing subsequent doses, booster doses could only be suggested to high-risk groups.

7.
PLoS Negl Trop Dis ; 15(4): e0009343, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33861754

RESUMEN

BACKGROUND: To eliminate trachoma as a public health problem, countries must achieve a district-level prevalence of trachomatous inflammation-follicular (TF) <5% in children ages 1-9 years. Re-emergence of TF could trigger additional rounds of mass drug/antibiotic administration (MDA), so accurate tools for use in surveys assessing trachoma prevalence are essential. METHODOLOGY & PRINCIPAL FINDINGS: We surveyed 2401 children ages 1-9 years from 50 villages in Kongwa, Tanzania, 2 years post-MDA and 1.5 years after an impact survey found TF <5% in the same villages. Our survey included multiple tools: clinical determination of TF, Cepheid testing for Chlamydia trachomatis infection, and testing for anti-pgp3 antibodies via multiplex bead array. Photographs of the upper tarsal conjunctiva were taken in a subset of children to corroborate the field grades. Overall TF prevalence in 1-9 year olds was 7.1% (95% CI: 5.6%-8.9%), which decreased with age (p = <0.0001). TF prevalence by village was heterogeneous, with 19 villages having TF <5% and 16 villages having TF >10%. There was a strong correlation between field and photo grading of TF (kappa = 0.69; 95% CI: 0.60-0.78) and between TF and infection, with 21.5% of TF-positive children also testing positive for infection, as compared to only 1.6% of TF-negative children (p = 0.0010). Overall seroprevalence was 18.2% (95% CI: 14.8%-22.1%), which increased with age (p = <0.0001). Notably, 1-2 year olds, who were born after the cessation of MDA and theoretically should not have had exposure to C. trachomatis in the absence of transmission, had an average seroprevalence of 6.7%. CONCLUSIONS & SIGNIFICANCE: Field TF prevalence, supported by photographic review and infection data, suggested re-emergence of trachoma in Kongwa. Moreover, seropositivity in the children born after cessation of MDA indicated exposure to C. trachomatis despite a previous survey finding of TF <5%. Examining seropositivity in specific age groups expected to have limited exposure to C. trachomatis can be used to detect re-emergence.


Asunto(s)
Antibacterianos/farmacología , Administración Masiva de Medicamentos , Tracoma/epidemiología , Anticuerpos Antibacterianos/análisis , Niño , Preescolar , Chlamydia trachomatis/inmunología , Femenino , Humanos , Lactante , Masculino , Prevalencia , Análisis de Regresión , Estudios Seroepidemiológicos , Encuestas y Cuestionarios , Tanzanía/epidemiología , Tracoma/tratamiento farmacológico
8.
Am J Trop Med Hyg ; 103(3): 1301-1307, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32067633

RESUMEN

The Macrolides Oraux pour Réduire les Décès avec un Oeil sur la Résistance study showed that administration of biannual, single-dose azithromycin to preschool children reduces mortality. We sought to evaluate its impact on azithromycin resistance. Thirty randomly selected communities in Kilosa district, Tanzania, were randomized to receive 6-monthly single-dose azithromycin (∼20 mg/kg) versus placebo treatment of children aged 1-59 months. From each community, 40 children (aged 1-59 months) were randomly selected at baseline, 12 and 24 months. Isolation and resistance testing of Streptococcus pneumoniae and Escherichia coli were evaluated using nasopharyngeal and rectal swabs, respectively. The carriage prevalence and the proportion of azithromycin-resistant isolates were determined using disk diffusion. At baseline, the characteristics of the randomly selected children were similar by treatment arms. Both at baseline and in annual cross-sectional surveys, rates of S. pneumoniae and E. coli isolation between treatment arms were similar. The proportions of azithromycin-resistant S. pneumoniae isolates in the children in communities treated with azithromycin versus placebo at baseline, 12 months, and 24 months were 26.5% (18.1%; P = 0.26), 26.8% (16.5%; P = 0.29), and 13.4% (17.0%; P = 0.57), respectively. The proportions of azithromycin-resistant E. coli isolates at baseline, 12 months, and 24 months in the azithromycin (versus placebo) arms were 14.9% (18.9%; P = 0.16), 21.5% (16.6%; P = 0.10), and 14.9% (14.7%; P = 0.95), respectively. Over the 24 months, the mean treatment coverage for the azithromycin and placebo was 76.9% and 74.8%, respectively (P = 0.49). Biannual administration of single-dose azithromycin to children did not appear to result in excess azithromycin resistance in S. pneumoniae and E. coli isolates over 24 months of follow-up.


Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Mortalidad del Niño , Escherichia coli/efectos de los fármacos , Macrólidos/administración & dosificación , Streptococcus pneumoniae/efectos de los fármacos , Preescolar , Estudios Transversales , Farmacorresistencia Bacteriana , Femenino , Humanos , Lactante , Masculino , Administración Masiva de Medicamentos , Nasofaringe , Prevalencia , Tanzanía/epidemiología
9.
Cancer Epidemiol Biomarkers Prev ; 29(11): 2261-2268, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32856600

RESUMEN

BACKGROUND: To inform policy makers in Tanzania if and how best to implement rapid HPV testing, we assessed the interobserver reproducibility of careHPV test at three different levels of the healthcare system in an urban and a rural region of Tanzania. METHODS: Women aged 30 to 50 years were screened by careHPV testing in two primary healthcare centers (PHC), two district hospitals (DiH), and two regional hospitals (ReH). Aliquots were retested at regional (ReH) and national referral laboratories (NRL). Reproducibility was evaluated using agreement and kappa index measures. Intralaboratory reproducibility was also evaluated in a set of 10 positive and 10 negative samples. RESULTS: Samples from 1,134 women were locally tested and retested at ReH and/or NRL. Test results from Dar es Salaam ReH and Kilimanjaro PHC showed clear quality problems including suspicion of contamination during testing or aliquoting. After excluding these samples, 18.8% of 743 women were HPV positive at clinic level. The resulting careHPV reproducibility at different levels of the healthcare system was very good [agreement 95.7%, 95% confidence interval (CI), 94.0-96.9; kappa, 0.86, 95% CI, 0.81-0.91]. Intralaboratory agreement was also very good across four different experiments, with Fleiss' kappa between 0.87 (95% CI, 0.61-1.00) and 1.00 (0.75-1.00). CONCLUSIONS: Rapid HPV testing was highly reproducible between lower and higher levels of the healthcare system in Tanzania; however, performance seems to be operator dependent. IMPACT: The careHPV test seems to be a feasible option for cervical cancer screening in an organized, decentralized system and in limited-resource settings if quality assurance measures are in place.


Asunto(s)
Papillomaviridae/genética , Infecciones por Papillomavirus/diagnóstico , Adulto , Detección Precoz del Cáncer , Femenino , Pruebas Genéticas , Humanos , Persona de Mediana Edad , Tanzanía
10.
Clin Infect Dis ; 49(6): 976-81, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19663598

RESUMEN

BACKGROUND: Monitoring of antiretroviral treatment (ART) with human immunodeficiency virus (HIV) viral loads, as recommended in industrialized countries, is rarely available in resource-limited settings because of the high costs and stringent requirements for storage and transport of plasma. Dried blood spots (DBS) can be an alternative to plasma, but the use of DBS has not been assessed under field conditions in rural Africa. The present study investigates the performance of DBS in HIV viral load monitoring of patients who received ART in rural Tanzania. PATIENTS AND METHODS: From November 2007 through June 2008, parallel plasma and DBS specimens were obtained from patients who received ART at Haydom Lutheran Hospital in rural Tanzania. DBS specimens were stored at tropical room temperature for 3 weeks before testing with the NucliSENS EasyQ HIV-1 v1.2 assay. Results obtained with DBS were compared with results obtained with use of a gold-standard plasma assay. RESULTS: Ninety-eight plasma-DBS pairs were compared, and plasma viral loads ranged from <40 to >1,000,000 copies/mL. The correlation between plasma and DBS viral load was strong (R(2) = 0.75). The mean difference (+/- standard deviation) was 0.04 +/ 0.57 log(10) copies/mL, and only 8 samples showed >1 log(10) copies/mL difference. HIV type 1 RNA was detected in 7%, 60%, and 100% of DBS specimens with corresponding plasma viral loads of 40-999, 1000-2999, and 3000 copies/mL, respectively. CONCLUSIONS: DBS, in combination with the NucliSENS EasyQ HIV-1 v1.2 asay, performed well in monitoring HIV viral loads in patients who received ART in rural Tanzania, although the sensitivity was reduced when viral burden was low. The use of DBS can simplify virological monitoring in resource-limited settings.


Asunto(s)
Sangre/virología , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Plasma/virología , Carga Viral , Adolescente , Adulto , Anciano , Antirretrovirales/uso terapéutico , Niño , Preescolar , Estudios Transversales , Países en Desarrollo , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Juego de Reactivos para Diagnóstico , Población Rural , Sensibilidad y Especificidad , Manejo de Especímenes/métodos , Tanzanía , Adulto Joven
11.
BMC Infect Dis ; 9: 108, 2009 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-19583845

RESUMEN

BACKGROUND: Virological response to antiretroviral treatment (ART) in rural Africa is poorly described. We examined virological efficacy and emergence of drug resistance in adults receiving first-line ART for up to 4 years in rural Tanzania. METHODS: Haydom Lutheran Hospital has provided ART to HIV-infected patients since October 2003. A combination of stavudine or zidovudine with lamivudine and either nevirapine or efavirenz is the standard first-line regimen. Nested in a longitudinal cohort study of patients consecutively starting ART, we carried out a cross-sectional virological efficacy survey between November 2007 and June 2008. HIV viral load was measured in all adults who had completed at least 6 months first-line ART, and genotypic resistance was determined in patients with viral load >1000 copies/mL. RESULTS: Virological response was measured in 212 patients, of whom 158 (74.5%) were women, and median age was 35 years (interquartile range [IQR] 29-43). Median follow-up time was 22.3 months (IQR 14.0-29.9). Virological suppression, defined as <400 copies/mL, was observed in 187 patients (88.2%). Overall, prevalence of > or =1 clinically significant resistance mutation was 3.9, 8.4, 16.7 and 12.5% in patients receiving ART for 1, 2, 3 and 4 years, respectively. Among those successfully genotyped, the most frequent mutations were M184I/V (64%), conferring resistance to lamivudine, and K103N (27%), Y181C (27%) and G190A (27%), conferring resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs), whereas 23% had thymidine analogue mutations (TAMs), associated with cross-resistance to all nucleoside reverse transcriptase inhibitors (NRTIs). Dual-class resistance, i.e. resistance to both NRTIs and NNRTIs, was found in 64%. CONCLUSION: Virological suppression rates were good up to 4 years after initiating ART in a rural Tanzanian hospital. However, drug resistance increased with time, and dual-class resistance was common, raising concerns about exhaustion of future antiretroviral drug options. This study might provide a useful forecast of drug resistance and demand for second-line antiretroviral drugs in rural Africa in the coming years.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , Adulto , Estudios de Cohortes , Estudios Transversales , Femenino , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Masculino , Tanzanía , Factores de Tiempo , Viremia/tratamiento farmacológico
12.
Diagn Microbiol Infect Dis ; 93(4): 293-298, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30709562

RESUMEN

Serological surveillance for trachoma could allow monitoring of transmission levels in areas that have achieved elimination targets. Platforms that allow testing in basic laboratories or testing of easy-to-manage samples such as dried blood spots would contribute to the feasibility of serologic testing. Blood from 506 1-12-year-olds in 2 villages in Kongwa district, Tanzania, was tested for antibodies against the antigen Pgp3. Whole blood, plasma, and dried blood spots (DBS) were tested in lab and field settings using a cassette-enclosed Pgp3 lateral flow assay (LFA-cassette) and a pared-back "dipstick" assay (LFA-dipstick). DBS were also tested with a bead-based multiplex assay (MBA). There was no significant difference in antibody positivity between the MBA and either LFA format (ranging from 42.5% to 48.4%). Interrater agreement between an expert rater and 3 different raters in field and lab settings was uniformly good, with Cohen's kappa >0.81 in all cases.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Chlamydia trachomatis/inmunología , Inmunoensayo/métodos , Tracoma/diagnóstico , Niño , Preescolar , Humanos , Lactante , Estudios Seroepidemiológicos , Tanzanía/epidemiología
13.
Ophthalmic Epidemiol ; 26(1): 1-6, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30543311

RESUMEN

PURPOSE: Trachoma, caused by repeated ocular infection with Chlamydia trachomatis, is the leading infectious cause of blindness worldwide and is targeted for elimination as a public health problem. We sought to determine whether a one-time azithromycin mass treatment would reduce trachomatous inflammation-follicular (TF) levels below the elimination threshold of 5% in communities with disease prevalence between 5 and 9.9%. METHODS: The study was conducted in 96 sub-village units (balozis) in the Kongwa district of Tanzania which were predicted from prior prevalence surveys to have TF between 5 and 9.9%. Balozis were randomly assigned to the intervention and control arms. The intervention arm received a single mass drug administration of azithromycin. At baseline and 12-month follow-up, ocular exams for trachoma, ocular swabs for detection of chlamydial DNA, and finger prick blood for analysis of anti-chlamydial antibody were taken. RESULTS: Comparison of baseline and 12-month follow-up showed no significant difference in the overall TF1-9 prevalence by balozi between control and treatment arms. In the treatment arm there was a significant reduction of ocular infection 12 months after treatment (p = 0.004) but no change in the control arm. No change in Pgp3-specific antibody responses were observed after treatment in the control or treatment arms. Anti-CT694 responses increased in both study arms (p = 0.009 for control arm and p = 0.04 for treatment arm). CONCLUSION: These data suggest that a single round of MDA may not be sufficient to decrease TF levels below 5% when TF1-9 is between 5 and 9.9% at baseline.


Asunto(s)
Azitromicina/administración & dosificación , Chlamydia trachomatis/genética , ADN Bacteriano/análisis , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Tracoma/tratamiento farmacológico , Antibacterianos/administración & dosificación , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Infecciones Bacterianas del Ojo/epidemiología , Infecciones Bacterianas del Ojo/microbiología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Prevalencia , Tanzanía/epidemiología , Factores de Tiempo , Tracoma/epidemiología , Tracoma/microbiología , Resultado del Tratamiento
14.
PLoS Negl Trop Dis ; 13(8): e0007632, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31412024

RESUMEN

BACKGROUND: Babesia, a tick-borne genus of intraerythrocytic parasites, is understudied in humans outside of established high-endemic areas. There is a paucity of data on Babesia in Africa, despite evidence that it is regionally present. A pilot study suggested that Babesia was present in a rural district of Tanzania. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional study was conducted July-August 2017: residents in a case hamlet that had clustering of subjects with high signal-to-cut off (S/CO) ratios for antibodies against B. microti in the pilot study, and a control hamlet that had lacked significant signal, were evaluated for B. microti. Subjects aged ≥15yrs (n = 299) underwent clinical evaluation and household inspections; 10ml whole blood was drawn for Babesia transcription mediated amplification (TMA), B. microti indirect fluorescent antibody testing (IFA) and rapid diagnostic testing (RDT) for Plasmodium spp. Subjects aged <15yrs (n = 266) underwent a RDT for Plasmodium and assessment by ELISA for B. microti antibodies. A total of 570 subjects participated (mean age 22 [<1 to 90yrs]) of whom 50.7% were female and 145 (25.5%) subjects were Plasmodium RDT positive (+). In those <15yrs, the median ELISA S/CO was 1.11 (IQR 0.80-1.48); the median S/CO in the case (n = 120) and control (n = 146) hamlets was 1.19 (IQR 0.81-1.48) and 1.06 (IQR 0.80-1.50) respectively (p = 0.4). Children ≥5yrs old were more likely to have a higher S/CO ratio than those <5yrs old (p<0.001). One hundred (38%) subjects <15yrs were Plasmodium RDT+. The median S/CO ratio (children <15yrs) did not differ by RDT status (p = 0.15). In subjects ≥15yrs, no molecular test was positive for Babesia, but four subjects (1.4%) were IFA reactive (two each at titers of 128 and 256). CONCLUSIONS/SIGNIFICANCE: The findings offer further support for Babesia in rural Tanzania. However, low prevalence of seroreactivity questions its clinical significance.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Babesia/inmunología , Babesiosis/epidemiología , Babesiosis/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Babesiosis/sangre , Babesiosis/parasitología , Niño , Preescolar , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Proyectos Piloto , Plasmodium/inmunología , Tanzanía/epidemiología , Adulto Joven
15.
J Virol ; 81(23): 13158-67, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17881457

RESUMEN

Herpes simplex virus type 2 (HSV-2) infects the genital mucosa and is one of the most common sexually transmitted viruses. Here we sequenced a segment comprising 3.5% of the HSV-2 genome, including genes coding for glycoproteins G, I, and E, from 27 clinical isolates from Tanzania, 10 isolates from Norway, and 10 isolates from Sweden. The sequence variation was low compared to that described for clinical HSV-1 isolates, with an overall similarity of 99.6% between the two most distant HSV-2 isolates. Phylogenetic analysis revealed a divergence into at least two genogroups arbitrarily designated A and B, supported by high bootstrap values and evolutionarily separated at the root. Genogroup A contained isolates collected in Tanzania, and genogroup B contained isolates collected in Tanzania and Scandinavia, implying that the genetic variability of HSV-2 is higher in Tanzania than in Scandinavia. Recombination network analysis and bootscan analysis revealed a complex pattern of phylogenetically conflicting informative sites in the sequence alignments. These signals were present in synonymous and nonsynonymous sites in all three genes and were not accumulated in specific regions, observations arguing against positive selection. Since the PHI test applied solely to synonymous sites revealed a high statistical probability of recombination, we suggest as a novel finding that homologous recombination is, as reported earlier for HSV-1 and varicella-zoster virus, a prominent feature in the evolution of HSV-2.


Asunto(s)
Herpes Genital/virología , Herpesvirus Humano 2/clasificación , Herpesvirus Humano 2/genética , Polimorfismo Genético , Recombinación Genética , Análisis por Conglomerados , ADN Viral/química , ADN Viral/genética , Evolución Molecular , Genotipo , Geografía , Herpesvirus Humano 2/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Noruega , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Suecia , Tanzanía , Proteínas del Envoltorio Viral/genética
16.
Am J Trop Med Hyg ; 99(4): 937-939, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30062986

RESUMEN

Scabies was recently added to the World Health Organization list of neglected tropical diseases. The ability to treat scabies with oral ivermectin makes a mass drug administration (MDA) campaign a feasible option for scabies control. Ivermectin MDA in communities endemic for lymphatic filariasis (LF) or onchocerciasis may already be having an impact on scabies. We examined the effect of ivermectin MDA for LF on scabies prevalence over 4 years in eight Tanzanian villages. At baseline, 4.4% (95% confidence interval [CI]: 3.7-5.4) of individuals tested positive for scabies, decreasing to 0.84% (95% CI: 0.51-1.4) after one round of ivermectin MDA but increased in Year 3 (2.5% [95% CI: 1.9-3.3]) and Year 4 (2.9% [95% CI: 2.2-3.8]). Most scabies cases were seen in children younger than 15 years. The data suggest that single-dose ivermectin MDA may not be effective in attaining long-term decreases when scabies prevalence is less than 5%.


Asunto(s)
Filariasis Linfática/epidemiología , Filaricidas/uso terapéutico , Ivermectina/uso terapéutico , Administración Masiva de Medicamentos/estadística & datos numéricos , Oncocercosis/epidemiología , Escabiosis/epidemiología , Adolescente , Animales , Niño , Preescolar , Estudios Transversales , Esquema de Medicación , Filariasis Linfática/tratamiento farmacológico , Filariasis Linfática/parasitología , Femenino , Humanos , Lactante , Masculino , Onchocerca/efectos de los fármacos , Onchocerca/patogenicidad , Onchocerca/fisiología , Oncocercosis/tratamiento farmacológico , Oncocercosis/parasitología , Prevalencia , Población Rural , Sarcoptes scabiei/efectos de los fármacos , Sarcoptes scabiei/patogenicidad , Sarcoptes scabiei/fisiología , Escabiosis/parasitología , Escabiosis/prevención & control , Tanzanía/epidemiología , Wuchereria bancrofti/efectos de los fármacos , Wuchereria bancrofti/patogenicidad , Wuchereria bancrofti/fisiología
17.
Am J Trop Med Hyg ; 99(1): 51-56, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29637884

RESUMEN

Babesia is a tick-borne intraerythrocytic parasite that is clinically and diagnostically similar to malaria parasite, conferring risk of misdiagnosis in areas where both parasites are endemic. Data on Babesia in humans in Africa are lacking, despite evidence that it is present in regional animal populations. Samples that were collected in November 2014 to July 2015 in Kilosa district, Tanzania, were evaluated for evidence of malaria and Babesia infection. Clinical data and laboratory samples (i.e., hemoglobin, rapid diagnostic testing [RDT] for malaria, peripheral blood smear, and dried blood spots) from a routine survey were available for analysis. Dried blood spots were tested using an investigational enzyme linked immunosorbent assay (ELISA) against Babesia microti. A total of 1,030 children aged 1 month to < 5 years were evaluated; 186 (18.1%) were malaria RDT positive, 180 (96.8%) of whom had peripheral smears reviewed; 70/180 (38.9%) were smear positive for parasites. The median (inter quartile range) and range of B. microti ELISA signal to cutoff (S/C) ratio was 0.10 (0.06-0.15) and 0.01-1.65, respectively; the S/C ratios were significantly higher in subjects ≥ 1 year as compared with those < 1 year old (P < 0.001). There was also a statistically significant association between a positive RDT for malaria and the Babesia S/C (median 0.09 versus 0.13 in RDT negative versus RDT positive, respectively; P < 0.001). The highest S/C ratios were disproportionately clustered in a few hamlets. The findings suggest that Babesia may be present in Kilosa district, Tanzania. However, serological cross-reactivity and false positivity, notably between Babesia and Plasmodium spp., cannot be definitively excluded and have implications for testing in other settings.


Asunto(s)
Babesia microti/crecimiento & desarrollo , Babesiosis/epidemiología , Malaria Falciparum/epidemiología , Plasmodium falciparum/crecimiento & desarrollo , Anticuerpos Antiprotozoarios/química , Babesia microti/inmunología , Babesiosis/sangre , Babesiosis/diagnóstico , Babesiosis/parasitología , Preescolar , Coinfección , Reacciones Cruzadas , Pruebas con Sangre Seca , Ensayo de Inmunoadsorción Enzimática , Eritrocitos/parasitología , Femenino , Humanos , Lactante , Recién Nacido , Malaria Falciparum/sangre , Malaria Falciparum/diagnóstico , Malaria Falciparum/parasitología , Masculino , Proyectos Piloto , Plasmodium falciparum/inmunología , Tanzanía/epidemiología
18.
Invest Ophthalmol Vis Sci ; 58(7): 3249-3253, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28660278

RESUMEN

Purpose: To assess for an association between conjunctival infection with nonchlamydial bacterial species and the presence of trachomatous scarring (TS) in women in central Tanzania. Methods: Cross-sectional data were collected from a random sample of women ages 18 and older in 47 trachoma-endemic communities in Kongwa, Tanzania. Each participant completed a survey, provided a conjunctival swab sample, and received an ocular exam to assess for TS. Biologic samples were cultured for bacterial growth and speciation. Contingency tables were used to assess the associations between TS and bacterial carriage. Results: Complete data was provided by 3882 women (80.7% of invitees). Of all samples, 14% resulted in a positive bacterial isolate. There was no association between TS and nonchlamydial bacterial carriage, whether assessed by species, pathogenicity, or in aggregate. There was a significant association between increasing age and TS severity, but not between age and bacterial carriage. No Corynebacterium was found in the swabs. Conclusions: This study found no association between TS and nonchlamydial ocular infections, although associations with Corynebacterium cannot be ruled out.


Asunto(s)
Cicatriz/etiología , Tracoma/complicaciones , Adulto , Antibacterianos/uso terapéutico , Cicatriz/epidemiología , Estudios Transversales , Femenino , Bacterias Gramnegativas/aislamiento & purificación , Humanos , Persona de Mediana Edad , Prevalencia , Tanzanía/epidemiología , Tracoma/epidemiología , Tracoma/microbiología , Adulto Joven
19.
J Virol Methods ; 125(2): 137-43, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15794983

RESUMEN

Herpes simplex viruses types 1 and 2 (HSV-1 and HSV-2), which are common worldwide, are so similar that antibodies directed against one serotype may crossreact with antigens from the other one. Methods for specific detection of antibodies against HSV-1 or HSV-2 are based upon the antigenicities of glycoproteins G. However, due to the cost, the available commercial methods may not readily be used in developing countries. A different enzyme-linked immunosorbent assay (ELISA) method, based upon a synthetic oligopeptide corresponding to an immunogenic region in glycoprotein G of HSV-2, has been used recently and successfully for detection of HSV-2 antibodies. In the present study, the sequences of a newly identified immunogenic and type-specific region in glycoprotein G of HSV-1 was used to synthesize three different, branched oligopeptides. The performances of these peptides in an ELISA were investigated by testing Scandinavian and African sera which were characterized by commercial ELISA and Western blotting methods and divided into four groups either lacking HSV antibodies, containing antibodies against one or the other virus, or against both types. The peptide which corresponded in sequence to the immunodominant region was as specific and sensitive by an ELISA as were the commercial methods. The method is inexpensive and reliable.


Asunto(s)
Anticuerpos Antivirales , Ensayo de Inmunoadsorción Enzimática/métodos , Herpesvirus Humano 1/aislamiento & purificación , Oligopéptidos/inmunología , Proteínas del Envoltorio Viral/análisis , Herpes Genital/diagnóstico , Herpes Genital/inmunología , Herpes Genital/virología , Herpesvirus Humano 1/inmunología , Herpesvirus Humano 2/inmunología , Humanos , Epítopos Inmunodominantes/genética , Epítopos Inmunodominantes/inmunología , Sensibilidad y Especificidad , Proteínas del Envoltorio Viral/inmunología
20.
Sci Rep ; 5: 18532, 2015 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-26687891

RESUMEN

Ocular infection with Chlamydia trachomatis can lead to trachoma, a leading infectious cause of blindness. Trachoma is targeted for elimination by 2020. Clinical grading for ocular disease is currently used for evaluating trachoma elimination programs, but serological surveillance can be a sensitive measure of disease transmission and provide a more objective testing strategy than clinical grading. We calculated the basic reproduction number from serological data in settings with high, medium, and low disease transmission based on clinical disease. The data showed a striking relationship between age seroprevalence and clinical data, demonstrating the proof-of-principle that age seroprevalence predicts transmission rates and therefore could be used as an indicator of decreased transmission of ocular trachoma.


Asunto(s)
Ceguera/patología , Chlamydia trachomatis/patogenicidad , Pruebas Serológicas , Tracoma/patología , Antígenos Bacterianos/sangre , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/sangre , Proteínas Bacterianas/inmunología , Ceguera/sangre , Ceguera/epidemiología , Ceguera/microbiología , Niño , Preescolar , Chlamydia trachomatis/aislamiento & purificación , Ojo/microbiología , Ojo/patología , Femenino , Humanos , Lactante , Masculino , Estudios Seroepidemiológicos , Tracoma/sangre , Tracoma/epidemiología , Tracoma/microbiología
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