Botswana is one of the four front line malaria elimination countries in Southern Africa, with malaria control activities that include routine vector control. Past and recent studies have shown that Anopheles arabiensis is the only known vector of Plasmodium parasites in the country. This report presents a preliminary evaluation on Anopheles species composition in seven districts of Botswana with some inferences on their vectorial role. Overall, 404 Anopheles mosquito females were collected, of which 196 were larvae collected from several breeding sites, and 208 were adults obtained from indoor pyrethrum spray catches (PSC). Anopheles arabiensis (58.9%) accounted for the highest relative frequency in 5 out of 7 districts sampled. The other species collected, among those identified, were barely represented: Anopheles longipalpis type C (16.3%), Anopheles parensis (8.9%), Anopheles quadriannulatus (5.4%), and Anopheles leesoni (0.2%). PCR test for human β-globin on mosquitoes collected by PSC showed that An. arabiensis and An. parensis had bitten human hosts. Moreover, An. arabiensis showed a non-negligible Plasmodium falciparum infection rate in two sites (3.0% and 2.5% in Chobe and Kweneng West districts, respectively). This work provides first time evidence of Anopheles diversity in several areas of Botswana. Anopheles arabiensis is confirmed to be widespread in all the sampled districts and to be vector of P. falciparum. Moreover, the presence of Anopheles funestus group in Botswana has been assessed. Further research, entomological surveillance activities and possibly vector control programmes need to be better developed and implemented as well as targeting outdoors resting vectors.
5 December 2018 in The American Journal of Tropical Medicine and Hygiene
Drug-resistant Plasmodium falciparum is a major threat to global malaria control and elimination efforts. In Botswana, a southern African country approaching malaria elimination, P. falciparum molecular data are not available. Parasites were assessed through pollymerase chain reaction (PCR) for confirmation of positive rapid diagnostic tests, multiplicity of infection (MOI), and drug resistance markers among isolates from clinical uncomplicated malaria cases collected at health facilities. Of 211 dried blood spot samples selected for the study, 186 (88.2%) were PCR positive for P. falciparum. The mean MOI based on MSP1 genotyping was 2.3 and was not associated with age. A high prevalence of wild-type parasites for pfcrt and pfmdr1 was found, with a haplotype frequency (K76/N86) of 88.8% and 17.7% of the isolates having two copies of the pfmdr1 gene. For pfATPase6, all the parasites carried the wild-type S769 allele. Sequencing showed no evidence of non-synonymous mutations associated with reduced artemisinin derivative sensitivity in the P. falciparum k13 gene. In conclusion, we found that P. falciparum parasites in Botswana were mostly wild type for the drug resistance markers evaluated. Yet, there was a high rate of a molecular marker associated to reduced sensitivity to lumefantrine. Our results indicate the need for systematic drug efficacy surveillance to complement malaria elimination efforts.
Introduction: Prostate cancer (CaP) is the most common malignancy and the second leading cause of cancer-related deaths among men in Botswana. Currently, diagnosing CaP relies on examining prostate biopsy samples, which can be challenging due to benign mimics. This study aims to evaluate the potential of Alpha-methyl acyl-CoA racemase (AMACR/p504s) and p63, as diagnostic markers for CaP. This may potentially validate the use of immunohistochemistry for detecting CaP in Botswana, where it is not routinely utilized. Methods: The study included 69 samples, comprising 5 prostatic chip specimens, 50 core biopsies, and 14 radical prostatectomy specimens. These cases were reviewed and categorized into CaP (49 cases) and benign prostatic hyperplasia (BPH) (20 cases). Immunohistochemistry was performed using AMACR/p504s and p63 immunohistochemical stains. Results: The study found that AMACR/p504s had a sensitivity of 96% and a specificity of 95%, while p63 had a sensitivity and specificity of 100%. PSA levels showed significant positive correlation with AMACR/p504s expression (P < 0.00001). Discussion: In this study, we have demonstrated the diagnostic utility of AMACR/p504s and p63 due to their high sensitivity and specificity in detecting CaP in Botswana, where these biomarkers are not yet widely used. Furthermore, utilizing these markers in conjunction with other diagnostic tools, such as PSA levels and morphological evaluation, could improve the diagnostic accuracy, especially in challenging cases where histopathological examination alone may be inconclusive.
PURPOSE: Cervical cancer remains a significant public health concern globally and particularly in sub-Saharan Africa, where high rates of HIV infection exacerbate cervical cancer incidence. Understanding the cervical microbiome and its role in cancer progression is essential, especially in regions where both cervical cancer incidence and HIV prevalence are high. This study aimed to characterize the cervical microbiome in women living with HIV (WLWH) and HIV-negative women with squamous cell carcinoma of the cervix in Botswana, compare the microbiome between before and after chemoradiation therapy (CRT) in WLWH, and assess the prognostic value of specific microbial taxa for overall survival (OS) in WLWH. PATIENTS AND METHODS: Cervical samples were collected from women with cervical cancer presenting to one hospital in 2018-2019. Patients' clinical data, including HIV status, were recorded. Microbial composition was analyzed using 16S rRNA gene sequencing. Microbiome diversity and composition were evaluated using alpha and beta diversity metrics. Differential microbial abundance was analyzed using linear discriminant analysis effect size. The association between microbial taxa and OS was explored using Cox proportional hazards regression. RESULTS: WLWH (n = 42) had a significantly lower Pielou evenness index than HIV-negative women (n = 11; 0.6 v 0.7, P = .02), suggesting a more imbalanced microbiome in WLWH. WLWH had higher levels of Parvimonas and members of the Corynebacteriaceae and Micrococcaceae families, suggesting a shift toward a more pathogenic microbiome. In WLWH, CRT did not significantly alter overall microbial diversity. However, Lactobacillus and Sutterella were enriched before treatment, reflecting a less pathogenic microbiome, whereas Ruminococcus and Phascolarctobacterium and the families Caulobacterales and Flavobacteriia were enriched after treatment, reflecting microbial adaptations to the altered immune and treatment environment. Notably, higher levels of Flavobacteriia after CRT were independently associated with worse OS in WLWH. CONCLUSION: Microbiome profiles differ between WLWH and HIV-negative women with cervical cancer in Botswana. The microbiome might have prognostic significance. Future research is needed to better understand the significance of the microbiota in cervical cancer progression and treatment outcomes and the potential role of microbiome-targeted interventions.