Capsule independent uptake of the fungal pathogen Cryptococcus neoformans into brain microvascular endothelial cells.

Cryptococcosis is a life-threatening fungal disease with a high rate of mortality among HIV/AIDS patients across the world. The ability to penetrate the blood-brain barrier (BBB) is central to the pathogenesis of cryptococcosis, but the way in which this occurs remains unclear. Here we use both mouse and human brain derived endothelial cells (bEnd3 and hCMEC/D3) to accurately quantify fungal uptake and survival within brain endothelial cells. Our data indicate that the adherence and internalisation of cryptococci by brain microvascular endothelial cells is an infrequent event involving small numbers of cryptococcal yeast cells. Interestingly, this process requires neither active signalling from the fungus nor the presence of the fungal capsule. Thus entry into brain microvascular endothelial cells is most likely a passive event that occurs following ‘trapping’ within capillary beds of the BBB

The global inequity of COVID-19 diagnostics : challenges and opportunities

Diagnostics for COVID-19 have advanced at an unprecedented pace over the last two years. Testing is a critical pillar of pandemic control, and is required for epidemiological tracking, treatment, and surveillance. Despite high quality SARS-CoV-2 viral diagnostic capability, there are vast global inequities in access. The Virology, Immunology, and Diagnostics Working Group(WG) of the COVID-19 Clinical Research Coalition (CRC) brings together experts in immunology, infectious diseases, and microbiology to advocate for equity-based COVID-19 research, prioritising solutions driven by communities in low-income and lower middle-income countries (LMICs).1 This commentary shares the unique perspective of the WG on the asymmetry in COVID-19 diagnostic access between low-income and high-income settings, the barriers to these disparities, and highlights opportunities to remedy these inequities.PostprintPeer reviewe

Non-prescribed antibiotic dispensing practices for symptoms of urinary tract infection in community pharmacies and accredited drug dispensing outlets in Tanzania : a simulated clients approach

This study was funded by HATUA project. The Holistic Approach to Unravel Antibacterial Resistance in East Africa is a 3-year Global Context Consortia Award (MR/S004785/1) funded by the National Institute for Health Research, Medical Research Council and the Department of Health and Social Care. The award is also part of the EDCTP2 programme supported by the European Union.Background Antibiotic dispensing without prescription is a major determinant of the emergence of Antimicrobial Resistance (AMR) which has impact on population health and cost of healthcare delivery. This study used simulated clients describing UTI like symptoms to explore compliance with regulation, variations in dispensing practices and drug recommendation, and quality of seller-client interaction on the basis of the gender of the client and the type of drug outlets in three regions in Tanzania. Method A total of 672 Accredited Drug Dispensing Outlets (ADDOs) and community pharmacies were visited by mystery clients (MCs). The study was conducted in three regions of Tanzania namely Kilimanjaro (180, 26.79%), Mbeya (169, 25.15%) and Mwanza (323, 48.07%) in March–May 2020. During data collection, information was captured using epicollect5 software before being analyzed using Stata version 13. Results Overall, 89.43% (CI: 86.87–91.55%) of drug sellers recommended antibiotics to clients who described UTI like symptoms but held no prescription and 58.93% were willing to sell less than the minimum recommended course. Female clients were more likely than male to be asked if they were taking other medications (27.2% vs 9.8%), or had seen a doctor (27.8% vs 14.7%), and more likely to be advised to consult a doctor (21.6% vs 9.0%); pharmacies addressed these issues more often than ADDOs (17.7% vs 13.2, 23.9% vs 16.6%, 17.7 vs 10.9% respectively). Sellers recommended 32 different drugs to treat the same set of symptoms, only 7 appear in the Tanzanian Standard Treatment Guidelines as recommended for UTI and 30% were 2nd and 3rd line drugs. ADDO sellers recommended 31 drug types (including 2nd and 3rd line) but had permission to stock only 3 (1st line) drugs. The most commonly suggested antibiotics were Azithromycin (35.4%) and ciprofloxacin (20.5%). Azithromycin was suggested more often in pharmacies (40.8%) than in ADDOs (34.4%) and more often to male clients (36.0%) than female (33.1%). Conclusion These findings support the need for urgent action to ensure existing regulations are adhered to and to promote the continuing professional development of drug sellers at all outlet levels to ensure compliance with regulation, high quality service and better antibiotic stewardship.Publisher PDFPeer reviewe

Genotypic Diversity Is Associated with Clinical Outcome and Phenotype in Cryptococcal Meningitis across Southern Africa.

Cryptococcal meningitis is a major cause of mortality throughout the developing world, yet little is known about the genetic markers underlying Cryptococcal virulence and patient outcome. We studied a cohort of 230 Cryptococcus neoformans (Cn) isolates from HIV-positive South African clinical trial patients with detailed clinical follow-up using multi-locus sequence typing and in vitro phenotypic virulence assays, correlating these data with clinical and fungal markers of disease in the patient. South African Cn displayed high levels of genetic diversity and locus variability compared to globally distributed types, and we identified 50 sequence types grouped within the main molecular types VNI, VNII and VNB, with 72% of isolates typed into one of seven 'high frequency' sequence types. Spatial analysis of patients' cryptococcal genotype was not shown to be clustered geographically, which might argue against recent local acquisition and in favour of reactivation of latent infection. Through comparison of MLST genotyping data with clinical parameters, we found a relationship between genetic lineage and clinical outcome, with patients infected with the VNB lineage having significantly worse survival (n=8, HR 3.35, CI 1.51-7.20, p=0.003), and this was maintained even after adjustment for known prognostic indicators and treatment regimen. Comparison of fungal genotype with in vitro phenotype (phagocytosis, laccase activity and CSF survival) performed on a subset of 89 isolates revealed evidence of lineage-associated virulence phenotype, with the VNII lineage displaying increased laccase activity (p=0.001) and ex vivo CSF survival (p=0.0001). These findings show that Cryptococcus neoformans is a phenotypically heterogeneous pathogen, and that lineage plays an important role in cryptococcal virulence during human infection. Furthermore, a detailed understanding of the genetic diversity in Southern Africa will support further investigation into how genetic diversity is structured across African environments, allowing assessment of the risks different ecotypes pose to infection

Barriers to the effective treatment and prevention of malaria in Africa: A systematic review of qualitative studies

<p>Abstract</p> <p>Background</p> <p>In Africa, an estimated 300-500 million cases of malaria occur each year resulting in approximately 1 million deaths. More than 90% of these are in children under 5 years of age. To identify commonly held beliefs about malaria that might present barriers to its successful treatment and prevention, we conducted a systematic review of qualitative studies examining beliefs and practices concerning malaria in sub-Saharan African countries.</p> <p>Methods</p> <p>We searched Medline and Scopus (1966-2009) and identified 39 studies that employed qualitative methods (focus groups and interviews) to examine the knowledge, attitudes, and practices of people living in African countries where malaria is endemic. Data were extracted relating to study characteristics, and themes pertaining to barriers to malaria treatment and prevention.</p> <p>Results</p> <p>The majority of studies were conducted in rural areas, and focused mostly or entirely on children. Major barriers to prevention reported included a lack of understanding of the cause and transmission of malaria (29/39), the belief that malaria cannot be prevented (7/39), and the use of ineffective prevention measures (12/39). Thirty-seven of 39 articles identified barriers to malaria treatment, including concerns about the safety and efficacy of conventional medicines (15/39), logistical obstacles, and reliance on traditional remedies. Specific barriers to the treatment of childhood malaria identified included the belief that a child with convulsions could die if given an injection or taken to hospital (10/39).</p> <p>Conclusion</p> <p>These findings suggest that large-scale malaria prevention and treatment programs must account for the social and cultural contexts in which they are deployed. Further quantitative research should be undertaken to more precisely measure the impact of the themes uncovered by this exploratory analysis.</p

Decreased availability of antimalarials in the private sector following the policy change from chloroquine to sulphadoxine-pyrimethamine in the Kilombero Valley, Tanzania

BACKGROUND: Malaria control strategies emphasize the need for prompt and effective treatment of malaria episodes. To increase treatment efficacy, Tanzania changed its first-line treatment from chloroquine to sulphadoxine-pyrimethamine (SP) in 2001. The effect of this policy change on the availability of antimalarials was studied in rural south-eastern Tanzania. METHODS: In 2001 and 2004, the study area was searched for commercial outlets selling drugs and their stocks were recorded. Household information was obtained from the local Demographic Surveillance System. RESULTS: From 2001 to 2004, the number of general shops stocking drugs increased by 15% and the number of drug stores nearly doubled. However, the proportion of general shops stocking antimalarials dropped markedly, resulting in an almost 50% decrease of antimalarial selling outlets. This led to more households being located farther from a treatment source. In 2004, five out of 25 studied villages with a total population of 13,506 (18%) had neither a health facility, nor a shop as source of malaria treatment. CONCLUSION: While the change to SP resulted in a higher treatment efficacy, it also led to a decreased antimalarial availability in the study area. Although there was no apparent impact on overall antimalarial use, the decline in access may have disproportionately affected the poorest and most remote groups. In view of the imminent policy change to artemisinin-based combination therapy these issues need to be addressed urgently if the benefits of this new class of antimalarials are to be extended to the whole population

Obstacles to prompt and effective malaria treatment lead to low community-coverage in two rural districts of Tanzania

BACKGROUND\ud \ud Malaria is still a leading child killer in sub-Saharan Africa. Yet, access to prompt and effective malaria treatment, a mainstay of any malaria control strategy, is sub-optimal in many settings. Little is known about obstacles to treatment and community-effectiveness of case-management strategies. This research quantified treatment seeking behaviour and access to treatment in a highly endemic rural Tanzanian community. The aim was to provide a better understanding of obstacles to treatment access in order to develop practical and cost-effective interventions.\ud \ud METHODS\ud \ud We conducted community-based treatment-seeking surveys including 226 recent fever episodes in 2004 and 2005. The local Demographic Surveillance System provided additional household information. A census of drug retailers and health facilities provided data on availability and location of treatment sources.\ud \ud RESULTS\ud \ud After intensive health education, the biomedical concept of malaria has largely been adopted by the community. 87.5% (78.2-93.8) of the fever cases in children and 80.7% (68.1-90.0) in adults were treated with one of the recommended antimalarials (at the time SP, amodiaquine or quinine). However, only 22.5% (13.9-33.2) of the children and 10.5% (4.0-21.5) of the adults received prompt and appropriate antimalarial treatment. Health facility attendance increased the odds of receiving an antimalarial (OR = 7.7) but did not have an influence on correct dosage. The exemption system for under-fives in public health facilities was not functioning and drug expenditures for children were as high in health facilities as with private retailers.\ud \ud CONCLUSION\ud \ud A clear preference for modern medicine was reflected in the frequent use of antimalarials. Yet, quality of case-management was far from satisfactory as was the functioning of the exemption mechanism for the main risk group. Private drug retailers played a central role by complementing existing formal health services in delivering antimalarial treatment. Health system factors like these need to be tackled urgently in order to translate the high efficacy of newly introduced artemisinin-based combination therapy (ACT) into equitable community-effectiveness and health-impact

FATAL DISSEMINATED CRYPTOCOCCOSIS WITH RENAL INVOLVEMENT IN AN HIV-INFECTED PATIENT

SUMMARY Introduction: We present a fatal case of disseminated cryptococcosis in a young man whose diagnosis of HIV infection was made at the time of admission to the emergency room. Case report: The patient was a twenty-three-year-old man, with a history of daily fever during one month associated with diarrhea, weight loss, headache, vomiting and generalized seizures. He also had a history of diabetes mellitus, alcoholism and drug addiction. Upon physical examination the patient was pale, disoriented and had periods of agitation. White blood cells count was 3,440/mm3 (5% lymphocytes), hemoglobin was 10g/dL, platelets were 83,000/ mm3. Creatinine was 0.7 mg/dL; urea 19 mg/dL; Na, K, and liver enzymes were within normal limits. Lactic dehydrogenase was 494 IU/L. Cerebrospinal fluid (CSF) analysis revealed 10 white blood cells/mm3 (58% neutrophils, 31% lymphocytes, 11% monocytes) and 2 red blood cells/mm3. India ink test revealed six Cryptococcus yeasts/mm3. CSF glucose was 122 mg/dL and protein was 36 mg/ dL. VDRL test was negative and anti-HIV test was positive. Intravenous hydration, insulin, phenytoin, fluconazole, pyrimethamine, sulfadiazine, folinic acid, and amphotericin B were started. The patient did not improve and became obtunded and hypotensive. He was intubated and put on mechanical respiration. He received vasoactive drugs and died less than 24 hours after admission. A postmortem examination was performed and revealed disseminated cryptococcosis, with severe involvement of the kidneys. Conclusion: Cryptococcosis, as a rule, is a systemic disease that affects mostly immunocompromised individuals, especially patients with AIDS. When diagnosed late in its course it has a very high mortality

Improvements in access to malaria treatment in Tanzania following community, retail sector and health facility interventions -- a user perspective

BACKGROUND\ud \ud The ACCESS programme aims at understanding and improving access to prompt and effective malaria treatment. Between 2004 and 2008 the programme implemented a social marketing campaign for improved treatment-seeking. To improve access to treatment in the private retail sector a new class of outlets known as accredited drug dispensing outlets (ADDO) was created in Tanzania in 2006. Tanzania changed its first-line treatment for malaria from sulphadoxine-pyrimethamine (SP) to artemether-lumefantrine (ALu) in 2007 and subsidized ALu was made available in both health facilities and ADDOs. The effect of these interventions on understanding and treatment of malaria was studied in rural Tanzania. The data also enabled an investigation of the determinants of access to treatment.\ud \ud METHODS\ud \ud Three treatment-seeking surveys were conducted in 2004, 2006 and 2008 in the rural areas of the Ifakara demographic surveillance system (DSS) and in Ifakara town. Each survey included approximately 150 people who had suffered a fever case in the previous 14 days.\ud \ud RESULTS\ud \ud Treatment-seeking and awareness of malaria was already high at baseline, but various improvements were seen between 2004 and 2008, namely: better understanding causes of malaria (from 62% to 84%); an increase in health facility attendance as first treatment option for patients older than five years (27% to 52%); higher treatment coverage with anti-malarials (86% to 96%) and more timely use of anti-malarials (80% to 93-97% treatments taken within 24 hrs). Unfortunately, the change of treatment policy led to a low availability of ALu in the private sector and, therefore, to a drop in the proportion of patients taking a recommended malaria treatment (85% to 53%). The availability of outlets (health facilities or drug shops) is the most important determinant of whether patients receive prompt and effective treatment, whereas affordability and accessibility contribute to a lesser extent.\ud \ud CONCLUSIONS\ud \ud An integrated approach aimed at improving understanding and treatment of malaria has led to tangible improvements in terms of people's actions for the treatment of malaria. However, progress was hindered by the low availability of the first-line treatment after the switch to ACT

Increasing malaria hospital admissions in Uganda between 1999 and 2009

<p>Abstract</p> <p>Background</p> <p>Some areas of Africa are witnessing a malaria transition, in part due to escalated international donor support and intervention coverage. Areas where declining malaria rates have been observed are largely characterized by relatively low baseline transmission intensity and rapid scaling of interventions. Less well described are changing patterns of malaria burden in areas of high parasite transmission and slower increases in control and treatment access.</p> <p>Methods</p> <p>Uganda is a country predominantly characterized by intense, perennial malaria transmission. Monthly pediatric admission data from five Ugandan hospitals and their catchments have been assembled retrospectively across 11 years from January 1999 to December 2009. Malaria admission rates adjusted for changes in population density within defined catchment areas were computed across three time periods that correspond to periods where intervention coverage data exist and different treatment and prevention policies were operational. Time series models were developed adjusting for variations in rainfall and hospital use to examine changes in malaria hospitalization over 132 months. The temporal changes in factors that might explain changes in disease incidence were qualitatively examined sequentially for each hospital setting and compared between hospital settings</p> <p>Results</p> <p>In four out of five sites there was a significant increase in malaria admission rates. Results from time series models indicate a significant month-to-month increase in the mean malaria admission rates at four hospitals (trend <it>P </it>< 0.001). At all hospitals malaria admissions had increased from 1999 by 47% to 350%. Observed changes in intervention coverage within the catchments of each hospital showed a change in insecticide-treated net coverage from <1% in 2000 to 33% by 2009 but accompanied by increases in access to nationally recommended drugs at only two of the five hospital areas studied.</p> <p>Conclusions</p> <p>The declining malaria disease burden in some parts of Africa is not a universal phenomena across the continent. Despite moderate increases in the coverage of measures to reduce infection and disease without significant coincidental increasing access to effective medicines to treat disease may not lead to severe disease burden reductions in high transmission areas of Africa. More data is needed from a wider range of malaria settings to provide an honest tracking progress of the impact of scaled intervention coverage in Africa.</p