7 research outputs found
Occurrence of pathogenic Vibrio cholerae serogroups 01 and 0139 in some estuaries of Tanzania
In this study, the occurrence of culturable Vibrio cholerae serogroup O1 and O139 in three selected Tanzanian Estuaries, Mzinga, Pangani and Ruvu were explored. A total of 480 water and plankton samples were collected along salinity gradients (fresh, brackish and marine waters). Samples were enriched in Alkaline Peptone Water (APW) and subsequently cultured on Thiosulfate Citrate Bile-Salt Sucrose (TCBS) agar. Resulting isolates were serially identified by oxidase test, API-20E test and monoclonal antibodies for V. cholerae serogroup O1 and O139. A total of 670 presumptive V. cholerae isolates were obtained from 416 samples (86.7%), where 137 (20.4%) were oxidase test positive. Out of the oxidase test positive, 96 (70.8%) were further confirmed by API 20E to be V. cholerae while only 8 isolates were ascertained by monoclonal antibodies to be V. cholerae O1 and 1 isolate to be V. cholerae O139. This indicated that, apart from the few V. cholerae O1 and O139 confirmed serogroups, there is still a large percentage of V. cholerae non-O1/O139. Similarly, both V. Cholerae serogroups O1 and non-O1/O139 were observed in clinical samples suggesting a close link between the existence of the bacterium in aquatic environments and cholera outbreak.Key words: Tanzanian Estuaries, V. cholerae, serogroupO1/O13
Co-variations of Cholera with Climatic and Environmental Parameters in Coastal Regions of Tanzania
The bacterium causing cholera, Vibrio cholerae, is essentially a marine organism and its ecological dynamics have been linked to oceanographic conditions and climate. We used autoregressive models with external inputs to identify potential relationships between number of cholera cases in the coastal regions of mainland Tanzania with climatic and environmental indices (maximum air temperature, sea surface temperature, wind speed and chlorophyll a). Results show that between 2004 and 2010 coastal regions of mainland Tanzania with approximately 21% of the total population accounted for approximately 50% of the cases and 40% of the total mortality. Significant co-variations were found between seasonally adjusted cases and coastal ocean chlorophyll a and to some degree sea surface temperature, both lagged by one to four months. Cholera cases in Dar es Salaam were also weakly related to the Indian Ocean Dipole Mode Index lagged by 5 months, suggesting that it may be possible to predict Cholera outbreaks for Dar es Salaam 5 months ahead of time. The results also suggest that the severity of cholera in coastal regions is set by conditions in the ocean and that longer-term environmental and climate parameters may be used to predict cholera outbreaks along the coastal regions
Absence of Germline BRCA1 c.68_69delAG and c.5266dupC Mutations among Hormone Receptor-negative Breast Cancer Patients: A First Impression at a Tertiary Cancer-care Facility in Tanzania
The germline BRCA1 c.68_69delAG (185delAG) and c.5266dupC (5382insC) mutations are associated with hormone receptor-negative breast cancer (BC). Limited studies have examined their contribution to alarming BC incidence in Sub Saharan Africa (SSA). Our study aimed to examine the contribution of germline BRCA1 c.68_69delAG and c.5266dupC mutations to BC incidence among hormone receptor-negative BC patients admitted to Ocean Road Cancer Institute in Tanzania. Face-to-face interviews were conducted to capture socio-demographic characteristics, anthropometric measurements, family history of cancer and reproductive information from each patient. Their histopathological data were extracted from the hospital medical records. The germline BRCA1 founder mutations were analyzed on blood samples using Sanger sequencing technology. The patients mean age at diagnosis was 47.05 ± 12.82 years. A family history of cancer was observed in 13.6% of patients. The germline BRCA1 c.68_69delAG and c.5266dupC mutations were not detected in the study group. Our findings indicate that the germline BRCA1 c.68_69delAG and c.5266dupC mutations do not contribute to BC manifestation in hormone receptor-negative BC patients in Tanzania. Thus, screening BC patients for these mutations has no clinical relevance. Our data further suggest that the c.68_69delAG and the c.5266dupC mutations should not be considered when developing genetic testing guidelines in Tanzania.
Keywords: Breast cancer, germline BRCA1 mutation, c.68_69delAG (185delAG), c.5266dupC (5382insC), Tanzani
The distribution of reproductive risk factors disclosed the heterogeneity of receptor-defined breast cancer subtypes among Tanzanian women
BACKGROUND: Recent epidemiological studies suggest that reproductive factors are associated with breast cancer (BC) molecular subtypes. However, these associations have not been thoroughly studied in the African populations. The present study aimed to investigate the prevalence of BC molecular subtypes and assess their association with reproductive factors in Tanzanian BC patients. METHODS: This hospital-based case-only cross-sectional study consisted of 263 histologically confirmed BC patients in Tanzania. Clinico-pathological data, socio-demographic characteristics, anthropometric measurements, and reproductive risk factors were examined using the Chi-square test and one-way ANOVA. The association among reproductive factors and BC molecular subtypes was analyzed using multinomial logistic regression. The heterogeneity of the associations was assessed using the Wald test. RESULTS: We found evident subtype heterogeneity for reproductive factors. We observed that post-menopausal status was more prevalent in luminal-A subtype, while compared to luminal-A subtype, luminal-B and HER-2 enriched subtypes were less likely to be found in post-menopausal women (OR: 0.21, 95%CI 0.10â0.41, pâ=â0.001; OR: 0.39, 95%CI 0.17â0.89, pâ=â0.026, respectively). Also, the luminal-B subtype was more likely to be diagnosed in patients aged â€â40 years than the luminal-A subtype (OR: 2.80, 95%CI 1.46â5.32, pâ=â0.002). Women who had their first full-term pregnancy at <â30 years were more likely to be of luminal-B (OR: 2.71, 95%CI 1.18â4.17, pâ=â0.018), and triple-negative (OR: 2.28, 95%CI 1.02â4.07, pâ=â0.044) subtypes relative to luminal-A subtype. Furthermore, we observed that breastfeeding might have reduced odds of developing luminal-A, luminal-B and triple-negative subtypes. Women who never breastfed were more likely to be diagnosed with luminal-B and triple-negative subtypes when compared to luminal-A subtype (OR: 0.46, 95%CI 0.22â0.95, pâ=â0.035; OR: 0.41, 95%CI 0.20â0.85, pâ=â0.017, respectively). . CONCLUSION: Our results are the first data reporting reproductive factors heterogeneity among BC molecular subtypes in Tanzania. Our findings suggest that breast-feeding may reduce the likelihood of developing luminal-A, luminal-B, and triple-negative subtypes. Meanwhile, the first full-term pregnancy after 30 years of age could increase the chance of developing luminal-A subtype, a highly prevalent subtype in Tanzania. More interventions to promote modifiable risk factors across multiple levels may most successfully reduce BC incidence in Africa. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12905-021-01536-6
Breast Cancer in East Africa: Prevalence and Spectrum of Germline SNV/Indel and CNVs in BRCA1 and BRCA2 Genes Among Breast Cancer Patients in Tanzania
Background: Growing prevalence and aggressiveness of breast cancer (BC) among East African women strongly indicate that the genetic risk factor implicated in the etiology of the disease may have a key role. Germline pathogenic variants in BRCA1 and BRCA2 (BRCA1/2) are known to increase the lifetime risk of BC. This study investigated the prevalence and spectrum of germline single nucleotide variant/insertion and deletion (SNV/indel), and copy number variations (CNVs) in BRCA1/2 among Tanzanian BC patients, and evaluated the associations of identified variants with patient's socio-demographic and histopathological characteristics. Methods: One hundred BC patients were examined for BRCA1/2 variants using next-generation sequencing (NGS). Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA) assay were performed for the confirmation of SNV/indel and CNVs, respectively. Results: Six germline SNV/indel pathogenic variants were detected from six unrelated patients. Five of these variants were identified in BRCA1, and one in BRCA2. We also identified, in one patient, one variant of uncertain clinical significance (VUS). CNV was not detected in any of the BC patients. Furthermore, we found that in our cohort, BRCA1/2 variant carriers were triple-negative BC patients (p = 0.019). Conclusions: Our study provides first insight into BC genetic landscape by the use of NGS in the under-represented East African Tanzanian populations. Our findings support the importance of genetic risk factors in BC etiology in Tanzania and showed a relatively high overall prevalence (6%) of germline BRCA1/2 pathogenic variants in BC patients. Therefore, our results indicate that BRCA1/2 pathogenic variants may well contribute to BC incidence in Tanzania. Thus, the identification of frequent variants in BRCA1/2 genes will enable implementation of rapid, inexpensive population-specific BRCA1/2 genetic testing, particularly for triple-negative BC patients known for their high prevalence in Tanzania. This will, in turn, greatly contributes to provide effective therapeutic strategies. © 2022 The Authors. Cancer Medicine published by John Wiley & Sons Ltd
The interplay between XPGâAsp1104His polymorphism and reproductive risk factors elevates risk of breast cancer in Tanzanian women: A multiple interaction analysis
Abstract Background Reproductive history and genetics are wellâknown risk factors of breast cancer (BC). Little is known about how these factors interact to effect BC. This study investigated the association of ten polymorphisms in DNA repair genes with BC susceptibility in the Tanzanian samples and further analyzed the association between reproductive risk factors and disease risk Methods A hospitalâbased caseâcontrol study in 263 histopathological confirmed BC patients and 250 ageâmatched cancerâfree controls was carried out. Allelic, genotypic, and haplotype association analyses were executed. Also, multifactor dimensionality reduction (MDR), and interaction dendrogram approaches were performed. Results The frequency of genotypic and allelic variants of XRCC1âArg399Gln (rs25487), XRCC2âArg188His (rs3218536), XRCC3âThr241Met (rs861539), XPGâAsp1104His (rs17655), and MSH2âGly322Asp (rs4987188) were significantly different between the groups (pâ<â0.05). Moreover, XRCC1âArg399Gln (rs25487), XRCC3âThr241Met (rs861539), and XPGâAsp1104His (rs17655) were associated with the increased risk of BC in coâdominant, dominant, recessive, and additive geneticâinheritance models (pâ<â0.05). XRCC1âArg/Gln genotype indicated a 3.1âfold increased risk of BC in preâmenopausal patients (p = 0.001) while XPGâHis/His genotype showed a 1.2âfold increased risk in younger BC patients (<40âyears) (p = 0.028). Asp/His+His/His genotypes indicated a 1.3âfold increased risk of BC in PR+ patients and a 1.1âfold decreased risk of BC in luminalâA patients (p = 0.014, p = 0.020, respectively). MDR analysis revealed a positive interaction between BC and the XPGâAsp1104His (rs17655) together with family history of cancer in the firstâdegree relatives. Dendrogram analysis indicated that the XPGâAsp1104His (rs17655) and family history of cancer in firstâdegree relatives were significantly synergistic and might be associated with an elevated risk of BC in Tanzania. Conclusions The XPGâAsp1104His (rs17655) might exert both independent and interactive effects on BC development in the Tanzanian women
Abstracts of Tanzania Health Summit 2020
This book contains the abstracts of the papers/posters presented at the Tanzania Health Summit 2020 (THS-2020) Organized by the Ministry of Health Community Development, Gender, Elderly and Children (MoHCDGEC); President Office Regional Administration and Local Government (PORALG); Ministry of Health, Social Welfare, Elderly, Gender, and Children Zanzibar; Association of Private Health Facilities in Tanzania (APHFTA); National Muslim Council of Tanzania (BAKWATA); Christian Social Services Commission (CSSC); & Tindwa Medical and Health Services (TMHS) held on 25â26 November 2020. The Tanzania Health Summit is the annual largest healthcare platform in Tanzania that attracts more than 1000 participants, national and international experts, from policymakers, health researchers, public health professionals, health insurers, medical doctors, nurses, pharmacists, private health investors, supply chain experts, and the civil society. During the three-day summit, stakeholders and decision-makers from every field in healthcare work together to find solutions to the countryâs and regional health challenges and set the agenda for a healthier future.
Summit Title: Tanzania Health SummitSummit Acronym: THS-2020Summit Date: 25â26 November 2020Summit Location: St. Gasper Hotel and Conference Centre in Dodoma, TanzaniaSummit Organizers: Ministry of Health Community Development, Gender, Elderly and Children (MoHCDGEC); President Office Regional Administration and Local Government (PORALG); Ministry of Health, Social Welfare, Elderly, Gender and Children Zanzibar; Association of Private Health Facilities in Tanzania (APHFTA); National Muslim Council of Tanzania (BAKWATA); Christian Social Services Commission (CSSC); & Tindwa Medical and Health Services (TMHS)