An essential endoplasmic reticulum-resident N-acetyltransferase ortholog in Plasmodium falciparum.

N-terminal acetylation is a common eukaryotic protein modification that involves the addition of an acetyl group to the N-terminus of a polypeptide. This modification is largely performed by cytosolic N-terminal acetyltransferases (NATs). Most associate with the ribosome, acetylating nascent polypeptides co-translationally. In the malaria parasite Plasmodium falciparum, exported effectors are thought to be translated into the endoplasmic reticulum (ER), processed by the aspartic protease plasmepsin V and then N-acetylated, despite having no clear access to cytosolic NATs. Here, we used inducible gene deletion and post-transcriptional knockdown to investigate the primary ER-resident NAT candidate, Pf3D7_1437000. We found that it localizes to the ER and is required for parasite growth. However, depletion of Pf3D7_1437000 had no effect on protein export or acetylation of the exported proteins HRP2 and HRP3. Despite this, Pf3D7_1437000 depletion impedes parasite development within the host red blood cell and prevents parasites from completing genome replication. Thus, this work provides further proof of N-terminal acetylation of secretory system proteins, a process unique to apicomplexan parasites, but strongly discounts a promising candidate for this post-translational modification.

Poly-basic peptides and polymers as new drug candidates against Plasmodium falciparum.

BACKGROUND: Plasmodium falciparum, the malaria-causing parasite, is a leading cause of infection-induced deaths worldwide. The preferred treatment approach is artemisinin-based combination therapy, which couples fast-acting artemisinin derivatives with longer-acting drugs, such as lumefantrine, mefloquine, and amodiaquine. However, the urgency for new treatments has risen due to the parasite's growing resistance to existing therapies. In this study, a common characteristic of the P. falciparum proteome-stretches of poly-lysine residues, such as those found in proteins related to adhesion and pathogenicity-is investigated for its potential to treat infected erythrocytes. METHODS: This study utilizes in vitro culturing of intra-erythrocytic P. falciparum to assess the ability of poly-lysine peptides to inhibit the parasite's growth, measured via flow cytometry of acridine orange-stained infected erythrocytes. The inhibitory effect of many poly-lysine lengths and modifications were tested this way. Affinity pull-downs and mass spectrometry were performed to identify the proteins interacting with these poly-lysines. RESULTS: A single dose of these poly-basic peptides can successfully diminish parasitemia in human erythrocytes in vitro with minimal toxicity. The effectiveness of the treatment correlates with the length of the poly-lysine peptide, with 30 lysine peptides supporting the eradication of erythrocytic parasites within 72 h. PEG-ylation of the poly-lysine peptides or utilizing poly-lysine dendrimers and polymers retains or increases parasite clearance efficiency and bolsters the stability of these potential new therapeutics. Lastly, affinity pull-downs and mass-spectrometry identify P. falciparum's outer membrane proteins as likely targets for polybasic peptide medications. CONCLUSION: Since poly-lysine dendrimers are already FDA-approved for drug delivery and this study displays their potency against intraerythrocytic P. falciparum, their adaptation as anti-malarial drugs presents a promising new therapeutic strategy for malaria.

Toxoplasma gondii requires its plant-like heme biosynthesis pathway for infection.

Heme, an iron-containing organic ring, is essential for virtually all living organisms by serving as a prosthetic group in proteins that function in diverse cellular activities ranging from diatomic gas transport and sensing, to mitochondrial respiration, to detoxification. Cellular heme levels in microbial pathogens can be a composite of endogenous de novo synthesis or exogenous uptake of heme or heme synthesis intermediates. Intracellular pathogenic microbes switch routes for heme supply when heme availability fluctuates in their replicative environment throughout infection. Here, we show that Toxoplasma gondii, an obligate intracellular human pathogen, encodes a functional heme biosynthesis pathway. A chloroplast-derived organelle, termed apicoplast, is involved in heme production. Genetic and chemical manipulation revealed that de novo heme production is essential for T. gondii intracellular growth and pathogenesis. Surprisingly, the herbicide oxadiazon significantly impaired Toxoplasma growth, consistent with phylogenetic analyses that show T. gondii protoporphyrinogen oxidase is more closely related to plants than mammals. This inhibition can be enhanced by 15- to 25-fold with two oxadiazon derivatives, lending therapeutic proof that Toxoplasma heme biosynthesis is a druggable target. As T. gondii has been used to model other apicomplexan parasites, our study underscores the utility of targeting heme biosynthesis in other pathogenic apicomplexans, such as Plasmodium spp., Cystoisospora, Eimeria, Neospora, and Sarcocystis.

An ortholog of Plasmodium falciparum chloroquine resistance transporter (PfCRT) plays a key role in maintaining the integrity of the endolysosomal system in Toxoplasma gondii to facilitate host invasion.

Toxoplasma gondii is an apicomplexan parasite with the ability to use foodborne, zoonotic, and congenital routes of transmission that causes severe disease in immunocompromised patients. The parasites harbor a lysosome-like organelle, termed the "Vacuolar Compartment/Plant-Like Vacuole" (VAC/PLV), which plays an important role in maintaining the lytic cycle and virulence of T. gondii. The VAC supplies proteolytic enzymes that contribute to the maturation of invasion effectors and that digest autophagosomes and endocytosed host proteins. Previous work identified a T. gondii ortholog of the Plasmodium falciparum chloroquine resistance transporter (PfCRT) that localized to the VAC. Here, we show that TgCRT is a membrane transporter that is functionally similar to PfCRT. We also genetically ablate TgCRT and reveal that the TgCRT protein plays a key role in maintaining the integrity of the parasite's endolysosomal system by controlling morphology of the VAC. When TgCRT is absent, the VAC dramatically increases in volume by ~15-fold and overlaps with adjacent endosome-like compartments. Presumably to reduce aberrant swelling, transcription and translation of endolysosomal proteases are decreased in ΔTgCRT parasites. Expression of subtilisin protease 1 is significantly reduced, which impedes trimming of microneme proteins, and significantly decreases parasite invasion. Chemical or genetic inhibition of proteolysis within the VAC reverses these effects, reducing VAC size and partially restoring integrity of the endolysosomal system, microneme protein trimming, and invasion. Taken together, these findings reveal for the first time a physiological role of TgCRT in substrate transport that impacts VAC volume and the integrity of the endolysosomal system in T. gondii.

Epidemiology of Tuberculosis and Progress Toward Meeting Global Targets - Worldwide, 2019.

Although tuberculosis (TB) is curable and preventable, in 2019, TB remained the leading cause of death from a single infectious agent worldwide and the leading cause of death among persons living with HIV infection (1). The World Health Organization's (WHO's) End TB Strategy set ambitious targets for 2020, including a 20% reduction in TB incidence and a 35% reduction in the number of TB deaths compared with 2015, as well as zero TB-affected households facing catastrophic costs (defined as costs exceeding 20% of annual household income) (2). In addition, during the 2018 United Nations High-Level Meeting on TB (UNHLM-TB), all member states committed to setting 2018-2022 targets that included provision of TB treatment to 40 million persons and TB preventive treatment (TPT) to 30 million persons, including 6 million persons living with HIV infection and 24 million household contacts of patients with confirmed TB (4 million aged <5 years and 20 million aged ≥5 years) (3,4). Annual data reported to WHO by 215 countries and territories, supplemented by surveys assessing TB prevalence and patient costs in some countries, were used to estimate TB incidence, the number of persons accessing TB curative and preventive treatment, and the percentage of TB-affected households facing catastrophic costs (1). Globally, TB illness developed in an estimated 10 million persons in 2019, representing a decline in incidence of 2.3% from 2018 and 9% since 2015. An estimated 1.4 million TB-related deaths occurred, a decline of 7% from 2018 and 14% since 2015. Although progress has been made, the world is not on track to achieve the 2020 End TB Strategy incidence and mortality targets (1). Efforts to expand access to TB curative and preventive treatment need to be substantially amplified for UNHLM-TB 2022 targets to be met.

Prevalence and genetic profiles of isoniazid resistance in tuberculosis patients: A multicountry analysis of cross-sectional data.

BACKGROUND: The surveillance of drug resistance among tuberculosis (TB) patients is central to combatting the global TB epidemic and preventing the spread of antimicrobial resistance. Isoniazid and rifampicin are two of the most powerful first-line anti-TB medicines, and resistance to either of them increases the risk of treatment failure, relapse, or acquisition of resistance to other drugs. The global prevalence of rifampicin resistance is well documented, occurring in 3.4% (95% CI 2.5%-4.4%) of new TB patients and 18% (95% CI 7.6%-31%) of previously treated TB patients in 2018, whereas the prevalence of isoniazid resistance at global and regional levels is less understood. In 2018, the World Health Organization (WHO) recommended a modified 6-month treatment regimen for people with isoniazid-resistant, rifampicin-susceptible TB (Hr-TB), which includes rifampicin, pyrazinamide, ethambutol, and levofloxacin. We estimated the global prevalence of Hr-TB among TB patients and investigated associated phenotypic and genotypic drug resistance patterns. METHODS AND FINDINGS: Aggregated drug resistance data reported to WHO from either routine continuous surveillance or nationally representative periodic surveys of TB patients for the period 2003-2017 were reviewed. Isoniazid data were available from 156 countries or territories for 211,753 patients. Among these, the global prevalence of Hr-TB was 7.4% (95% CI 6.5%-8.4%) among new TB patients and 11.4% (95% CI 9.4%-13.4%) among previously treated TB patients. Additional data on pyrazinamide and levofloxacin resistance were available from 6 countries (Azerbaijan, Bangladesh, Belarus, Pakistan, the Philippines, and South Africa). There were no cases of resistance to both pyrazinamide and levofloxacin among Hr-TB patients, except for the Philippines (1.8%, 95% CI 0.2-6.4) and Belarus (5.3%, 95% CI 0.1-26.0). Sequencing data for all genomic regions involved in isoniazid resistance were available for 4,563 patients. Among the 1,174 isolates that were resistant by either phenotypic testing or sequencing, 78.6% (95% CI 76.1%-80.9%) had resistance-conferring mutations in the katG gene and 14.6% (95% CI 12.7%-16.8%) in both katG and the inhA promoter region. For 6.8% (95% CI 5.4%-8.4%) of patients, mutations occurred in the inhA promoter alone, for whom an increased dose of isoniazid may be considered. The main limitations of this study are that most analyses were performed at the national rather than individual patient level and that the quality of laboratory testing may vary between countries. CONCLUSIONS: In this study, the prevalence of Hr-TB among TB patients was higher than the prevalence of rifampicin resistance globally. Many patients with Hr-TB would be missed by current diagnostic algorithms driven by rifampicin testing, highlighting the need for new rapid molecular technologies to ensure access to appropriate treatment and care. The low prevalence of resistance to pyrazinamide and fluoroquinolones among patients with Hr-TB provides further justification for the recommended modified treatment regimen.

National tuberculosis prevalence surveys in Africa, 2008-2016: an overview of results and lessons learned.

OBJECTIVE AND METHODS: Worldwide, tuberculosis (TB) is the leading cause of death from a single infectious agent. In many countries, national TB prevalence surveys are the only way to reliably measure the burden of TB disease and can also provide other evidence to inform national efforts to improve TB detection and treatment. Our objective was to synthesise the results and lessons learned from national surveys completed in Africa between 2008 and 2016, to complement a previous review for Asia. RESULTS: Twelve surveys completed in Africa were identified: Ethiopia (2010-2011), Gambia (2011-2013), Ghana (2013), Kenya (2015-2016), Malawi (2013-2014), Nigeria (2012), Rwanda (2012), Sudan (2013-2014), Tanzania (2011-2012), Uganda (2014-2015), Zambia (2013-2014) and Zimbabwe (2014). The eligible population in all surveys was people aged ≥15 years who met residency criteria. In total 588 105 individuals participated, equivalent to 82% (range 57-96%) of those eligible. The prevalence of bacteriologically confirmed pulmonary TB disease in those ≥15 years varied from 119 (95% CI 79-160) per 100 000 population in Rwanda and 638 (95% CI 502-774) per 100 000 population in Zambia. The male:female ratio was 2.0 overall, ranging from 1.2 (Ethiopia) to 4.1 (Uganda). Prevalence per 100 000 population generally increased with age, but the absolute number of cases was usually highest among those aged 35-44 years. Of identified TB cases, 44% (95% CI 40-49) did not report TB symptoms during screening and were only identified as eligible for diagnostic testing due to an abnormal chest X-ray. The overall ratio of prevalence to case notifications was 2.5 (95% CI 1.8-3.2) and was consistently higher for men than women. Many participants who did report TB symptoms had not sought care; those that had were more likely to seek care in a public health facility. HIV prevalence was systematically lower among prevalent cases than officially notified TB patients with an overall ratio of 0.5 (95% CI 0.3-0.7). The two main study limitations were that none of the surveys included people <15 years, and 5 of 12 surveys did not have data on HIV status. CONCLUSIONS: National TB prevalence surveys implemented in Africa between 2010 and 2016 have contributed substantial new evidence about the burden of TB disease, its distribution by age and sex, and gaps in TB detection and treatment. Policies and practices to improve access to health services and reduce under-reporting of detected TB cases are needed, especially among men. All surveys provide a valuable baseline for future assessment of trends in TB disease burden.

OBJECTIF ET MÉTHODES: Dans le monde entier, la tuberculose (TB) est la principale cause de décès par un seul agent infectieux. Dans de nombreux pays, les surveillances nationales de prévalence de la TB sont le seul moyen de mesurer de manière fiable la charge de la TB et peuvent également fournir d'autres données pour éclairer les efforts nationaux visant à améliorer la détection et le traitement de la TB. Notre objectif était de synthétiser les résultats et les leçons tirées des surveillances nationales réalisées en Afrique entre 2008 et 2016, pour complémenter une analyse précédente pour l'Asie. RÉSULTATS: Douze surveillances réalisées en Afrique ont été identifiés: Ethiopie (2010-2011), Gambie (2011-2013), Ghana (2013), Kenya (2015-2016), Malawi (2013-2014), Nigeria (2012), Rwanda (2012), Soudan (2013-2014 ), Tanzanie (2011-2012), Ouganda (2014-2015), Zambie (2013-2014) et Zimbabwe (2014). La population éligible dans toutes les surveillances était des personnes ≥15 ans qui répondaient aux critères de résidence. Au total, 588.105 personnes ont participé, ce qui équivaut à 82% (entre 57% et 96% ) des personnes éligibles. La prévalence de la TB pulmonaire bactériologiquement confirmée chez les ≥15 ans variait de 119 (IC95%: 79-160) pour 100.000 habitants au Rwanda et 638 (IC95%: 502 à 774) pour 100.000 habitants en Zambie. Le ratio hommes/femmes était globalement de 2,0, allant de 1,2 (Ethiopie) à 4,1 (Ouganda). La prévalence pour 100.000 habitants augmentait généralement avec l'âge, mais le nombre absolu de cas était généralement le plus élevé chez les 35 à 44 ans. Parmi les cas de TB identifiés, 44% (IC95%: 40-49) n'ont pas rapporté de symptômes de TB lors du dépistage et n'ont été identifiés comme éligibles aux tests de diagnostic qu'en raison d'une radiographie pulmonaire anormale. Le rapport global entre la prévalence et les notifications de cas était de 2,5 (IC95%: 1,8-3,2) et était systématiquement plus élevé pour les hommes que pour les femmes. De nombreux participants qui avaient rapporté des symptômes de TB n'avaient pas recherché des soins; ceux qui en avaient étaient plus susceptibles de rechercher des soins dans un établissement de santé publique. La prévalence du VIH était systématiquement plus faible parmi les cas prévalents que chez les patients TB officiellement notifiés avec un rapport global de 0,5 (IC95% 0,3 - 0,7). Les deux principales limitations de l'étude étaient les suivantes: aucune des surveillances n'incluait des personnes de moins de 15 ans et 5 des 12 surveillances ne contenaient pas de données sur le statut VIH. CONCLUSIONS: Les surveillances nationales sur la prévalence de la TB en Afrique menées entre 2010 et 2016 ont fourni de nouvelles données sur la charge de morbidité de la TB, la répartition par âge et par sexe, et les lacunes dans la détection et le traitement de la TB. Des politiques et des pratiques pour améliorer l'accès aux services de santé et réduire la sous-déclaration des cas de TB détectés sont nécessaires, en particulier chez les hommes. Toutes les surveillances fournissent une base précieuse pour l'évaluation future des tendances de la charge de morbidité TB.

Global Epidemiology of Tuberculosis and Progress Toward Meeting Global Targets - Worldwide, 2018.

Worldwide, tuberculosis (TB) is the leading cause of death from a single infectious disease agent (1), including among persons living with human immunodeficiency virus (HIV) infection (2). A World Health Organization (WHO) initiative, The End Tuberculosis Strategy, set ambitious targets for 2020-2035, including 20% reduction in TB incidence and 35% reduction in the absolute number of TB deaths by 2020 and 90% reduction in TB incidence and 95% reduction in TB deaths by 2035, compared with 2015 (3). This report evaluated global progress toward these targets based on data reported by WHO (1). Annual TB data routinely reported to WHO by 194 member states were used to estimate TB incidence and mortality overall and among persons with HIV infection, TB-preventive treatment (TPT) initiation, and drug-resistant TB for 2018 (1). In 2018, an estimated 10 million persons had incident TB, and 1.5 million TB-related deaths occurred, representing 2% and 5% declines from 2017, respectively. The number of persons with both incident and prevalent TB remained highest in the WHO South-East Asia and African regions. Decreases in the European region were on track to meet 2020 targets. Globally, among persons living with HIV, 862,000 incident TB cases occurred, and 1.8 million persons initiated TPT. Rifampicin-resistant or multidrug-resistant TB occurred among 3.4% of persons with new TB and 18% among persons who were previously treated for TB (overall, among 4.8% of persons with TB). The modest decreases in the number of persons with TB and the number of TB-related deaths were consistent with recent trends, and new and substantial progress was observed in increased TPT initiation among persons living with HIV. However, to meet the global targets for 2035, more intensive efforts are needed by public health partners to decrease TB incidence and deaths and increase the number of persons receiving TB curative and preventive treatment. Innovative approaches to case finding, scale-up of TB preventive treatment, use of newer TB treatment regimens, and prevention and control of HIV will contribute to decreasing TB.

Global Epidemiology of Tuberculosis and Progress Toward Achieving Global Targets - 2017.

Worldwide, tuberculosis (TB) is the leading cause of death from a single infectious disease agent (1) and the leading cause of death among persons living with human immunodeficiency virus (HIV) infection, accounting for approximately 40% of deaths in this population (2). The United Nations' (UN) Sustainable Development Goals (3) and the World Health Organization's (WHO's) End TB Strategy (4) have defined ambitious targets for 2020-2035, including a 35% reduction in the absolute number of TB deaths and a 20% reduction in TB incidence by 2020, compared with 2015 (4). Since 2000, WHO has produced annual TB estimates for all countries (1). Global and regional disease estimates were evaluated for 2017 to determine progress toward meeting targets. In 2017, an estimated 10 million incident cases of TB and 1.57 million TB deaths occurred, representing 1.8% and 3.9% declines, respectively, from 2016. Numbers of TB cases and disease incidence were highest in the WHO South-East Asia and Africa regions, and 9% of cases occurred among persons with HIV infection. Rifampicin-resistant (RR) or multidrug-resistant (MDR) (resistance to at least both isoniazid and rifampicin) TB occurred among 3.6% and 18% of new and previously treated TB cases, respectively (5.6% among all cases). Overall progress in global TB elimination was modest in 2017, consistent with that in recent years (1); intensified efforts to improve TB diagnosis, treatment, and prevention are required to meet global targets for 2020-2035.

Global Epidemiology of Tuberculosis.

Tuberculosis (TB) was the underlying cause of 1.3 million deaths among human immunodeficiency virus (HIV)-negative people in 2016, exceeding the global number of HIV/acquired immune deficiency syndrome (AIDS) deaths. In addition, TB was a contributing cause of 374,000 HIV deaths. Despite the success of chemotherapy over the past seven decades, TB is the top infectious killer globally. In 2016, 10.4 million new cases arose, a number that has remained stable since the beginning of the 21th century, frustrating public health experts tasked to design and implement interventions to reduce the burden of TB disease worldwide. Ambitious targets for reductions in the epidemiological burden of TB have been set within the context of the Sustainable Development Goals (SDGs) and the End TB Strategy. Achieving these targets is the focus of national and international efforts, and demonstrating whether or not they are achieved is of major importance to guide future and sustainable investments. This article reviews epidemiological facts about TB, trends in the magnitude of the burden of TB and factors contributing to it, and the effectiveness of the public health response.

Tuberculosis control in the era of HIV.

Without HIV, the tuberculosis (TB) epidemic would now be in decline almost everywhere. However, instead of looking forward to the demise of TB, countries that are badly affected by HIV are struggling against a rising tide of HIV-infected patients with TB. As a consequence, global TB control policies have had to be revised and control of TB now demands increased investment. This paper assesses what is being done to address the issue and what remains to be done.

Multidrug-resistant tuberculosis around the world: what progress has been made?

Multidrug-resistant tuberculosis (MDR-TB) (resistance to at least isoniazid and rifampicin) will influence the future of global TB control. 88% of estimated MDR-TB cases occur in middle- or high-income countries, and 60% occur in Brazil, China, India, the Russian Federation and South Africa. The World Health Organization collects country data annually to monitor the response to MDR-TB. Notification, treatment enrolment and outcome data were summarised for 30 countries, accounting for >90% of the estimated MDR-TB cases among notified TB cases worldwide. In 2012, a median of 14% (interquartile range 6-50%) of estimated MDR-TB cases were notified in the 30 countries studied. In 15 of the 30 countries, the number of patients treated for MDR-TB in 2012 (71 681) was >50% higher than in 2011. Median treatment success was 53% (interquartile range 40-70%) in the 25 countries reporting data for 30 021 MDR-TB cases who started treatment in 2010. Although progress has been noted in the expansion of MDR-TB care, urgent efforts are required in order to provide wider access to diagnosis and treatment in most countries with the highest burden of MDR-TB.

Cost-effectiveness of a comprehensive programme for drug-resistant tuberculosis in China.

OBJECTIVE: To investigate the cost-effectiveness of a comprehensive programme for drug-resistant tuberculosis launched in four sites in China in 2011. METHODS: In 2011-2012, we reviewed the records of 172 patients with drug-resistant tuberculosis who enrolled in the comprehensive programme and we collected relevant administrative data from hospitals and China's public health agency. For comparison, we examined a cohort of 81 patients who were treated for drug-resistant tuberculosis in 2006-2009. We performed a cost-effectiveness analysis, from a societal perspective, that included probabilistic uncertainty. We measured early treatment outcomes based on three-month culture results and modelled longer-term outcomes to facilitate estimation of the comprehensive programme's cost per disability-adjusted life-year (DALY) averted. FINDINGS: The comprehensive programme cost 8837 United States dollars (US$) per patient treated. Low enrolment rates meant that some fixed costs were higher, per patient, than expected. Although the comprehensive programme appeared 30 times more costly than the previous one, it resulted in greater health benefits. The comprehensive programme, which cost US$ 639 (95% credible interval: 112 to 1322) per DALY averted, satisfied the World Health Organization's criterion for a very cost-effective intervention. CONCLUSION: The comprehensive programme, which included rapid screening, standardized care and financial protection, improved individual outcomes for MDR tuberculosis in a cost-effective manner. To support post-2015 global heath targets, the comprehensive programme should be expanded to non-residents and other areas of China.

National tuberculosis prevalence surveys in Asia, 1990-2012: an overview of results and lessons learned.

OBJECTIVE AND METHODS: In many countries, national tuberculosis (TB) prevalence surveys are the only way to reliably measure the burden of TB disease and monitor trends. They can also provide evidence about the current performance of TB care and control and how this could be improved. We developed an inventory of Asian surveys from 1953 to 2012 and then compiled and analysed a standard set of data for all national surveys implemented between 1990 (the baseline year for 2015 global TB targets) and 2012. RESULTS: There were 21 surveys in 12 countries between 1990 and 2012; published results were available for 18. The participation rate was at least 80% and often much higher except for two surveys in Thailand. The prevalence of bacteriologically-positive TB disease among adults aged ≥15 years varied widely among countries (1.2 per 1000 population in China in 2010 to 15 per 1000 population in Cambodia in 2002), but age and sex distribution patterns were consistent with a progressive increase in rates of disease by age, and men accounting for 66-75% of prevalent cases. A high proportion of cases (40-79% across all surveys) did not report TB symptoms that met screening criteria (generally cough of 2-3 weeks or more, and blood in the sputum) and were only detected due to chest X-ray screening of all survey participants; this proportion increased over time in countries with repeat survey data. The ratio of prevalent cases to cases notified to national TB programmes was typically around two, but was as high as three in Lao PDR and Pakistan even after the internationally recommended TB control strategy had been implemented nationwide for several years. Four countries (China, Cambodia, the Republic of Korea and the Philippines demonstrated declines in smear or culture-positive pulmonary TB prevalence of approximately 50% over 10 years. CONCLUSIONS: National TB prevalence surveys in Asia show that large reductions in the prevalence of TB disease can be achieved within a decade, that men bear much more of the burden than women and that the epidemic is ageing. Comparisons among countries show that more can be achieved in TB control in some countries with existing strategies and technologies. However, with many prevalent cases not reporting classic TB symptoms, all countries face the challenge of defining and implementing strategies that will result in earlier detection and treatment of cases.

On the spread and control of MDR-TB epidemics: an examination of trends in anti-tuberculosis drug resistance surveillance data.

BACKGROUND: Multidrug resistant tuberculosis (MDR-TB) poses serious challenges for tuberculosis control in many settings, but trends of MDR-TB have been difficult to measure. METHODS: We analyzed surveillance and population-representative survey data collected worldwide by the World Health Organization between 1993 and 2012. We examined setting-specific patterns associated with linear trends in the estimated per capita rate of MDR-TB among new notified TB cases to generate hypotheses about factors associated with trends in the transmission of highly drug resistant tuberculosis. RESULTS: 59 countries and 39 sub-national settings had at least three years of data, but less than 10% of the population in the WHO-designated 27-high MDR-TB burden settings were in areas with sufficient data to track trends. Among settings in which the majority of MDR-TB was autochthonous, we found 10 settings with statistically significant linear trends in per capita rates of MDR-TB among new notified TB cases. Five of these settings had declining trends (Estonia, Latvia, Macao, Hong Kong, and Portugal) ranging from decreases of 3% to 14% annually, while five had increasing trends (four individual oblasts of the Russian Federation and Botswana) ranging from 14% to 20% annually. In unadjusted analysis, better surveillance indicators and higher GDP per capita were associated with declining MDR-TB, while a higher existing absolute burden of MDR-TB was associated with an increasing trend. CONCLUSIONS: Only a small fraction of countries in which the burden of MDR-TB is concentrated currently have sufficient surveillance data to estimate trends in drug-resistant TB. Where trend analysis was possible, smaller absolute burdens of MDR-TB and more robust surveillance systems were associated with declining per capita rates of MDR-TB among new notified cases.

Beyond UHC: monitoring health and social protection coverage in the context of tuberculosis care and prevention.

Tuberculosis (TB) remains a major global public health problem. In all societies, the disease affects the poorest individuals the worst. A new post-2015 global TB strategy has been developed by WHO, which explicitly highlights the key role of universal health coverage (UHC) and social protection. One of the proposed targets is that "No TB affected families experience catastrophic costs due to TB." High direct and indirect costs of care hamper access, increase the risk of poor TB treatment outcomes, exacerbate poverty, and contribute to sustaining TB transmission. UHC, conventionally defined as access to health care without risk of financial hardship due to out-of-pocket health care expenditures, is essential but not sufficient for effective and equitable TB care and prevention. Social protection interventions that prevent or mitigate other financial risks associated with TB, including income losses and non-medical expenditures such as on transport and food, are also important. We propose a framework for monitoring both health and social protection coverage, and their impact on TB epidemiology. We describe key indicators and review methodological considerations. We show that while monitoring of general health care access will be important to track the health system environment within which TB services are delivered, specific indicators on TB access, quality, and financial risk protection can also serve as equity-sensitive tracers for progress towards and achievement of overall access and social protection.

Drug-resistant tuberculosis in the WHO European Region: an analysis of surveillance data.

To review the latest information about levels of anti-tuberculosis (TB) drug resistance in the European Region of the World Health Organization (WHO) and time-trends in multidrug-resistant TB (resistance to isoniazid and rifampicin; MDR-TB) over the past fifteen years. We analysed data on drug resistance among new and previously treated TB cases reported from 1997 to 2012. Data are collected in surveys of representative samples of TB patients or from surveillance systems based on diagnostic drug susceptibility testing. A total of 15.7% (95% confidence limits (CI): 9.5-21.9) of new and 45.3% (95%CI: 39.2-51.5) of previously treated TB cases are estimated to have MDR-TB in the Region. Extensively drug-resistant TB (MDR-TB and resistance to fluoroquinolones and second-line injectables; XDR-TB) had been reported by 38 of the 53 countries of the region (72%). The proportion of MDR-TB cases with XDR-TB is 11.4% (95%CI: 8.6-14.2). Between 1997 and 2012, population rates of MDR-TB declined in Estonia, Latvia and Germany and increased in the United Kingdom, Sweden and Tomsk Oblasts of the Russian Federation. Surveillance of drug resistance has been strengthened in the WHO European Region, which has the highest proportions of MDR-TB and XDR-TB ever reported globally. More complete data are needed particularly from the Russian Federation.

MAPK/ERK activation in macrophages promotes Leishmania internalization and pathogenesis.

The obligate intracellular parasite Leishmania binds several receptors to trigger uptake by phagocytic cells, ultimately resulting in visceral or cutaneous leishmaniasis. A series of signaling pathways in host cells, which are critical for establishment and persistence of infection, are activated during Leishmania internalization. Thus, preventing Leishmania uptake by phagocytes could be a novel therapeutic strategy for leishmaniasis. However, the host cellular machinery mediating promastigote and amastigote uptake is not well understood. Here, using small molecule inhibitors of Mitogen-activated protein/Extracellular signal regulated kinases (MAPK/ERK), we demonstrate that ERK1/2 mediates Leishmania amazonensis uptake and (to a lesser extent) phagocytosis of beads by macrophages. We find that inhibiting host MEK1/2 or ERK1/2 leads to inefficient amastigote uptake. Moreover, using inhibitors and primary macrophages lacking spleen tyrosine kinase (SYK) or Abl family kinases, we show that SYK and Abl family kinases mediate Raf, MEK, and ERK1/2 activity and are necessary for uptake. Finally, we demonstrate that trametinib, a MEK1/2 inhibitor used to treat cancer, reduces disease severity and parasite burden in Leishmania-infected mice, even if it is started after lesions develop. Our results show that maximal Leishmania infection requires MAPK/ERK and highlight potential for MAPK/ERK-mediated signaling pathways to be novel therapeutic targets for leishmaniasis.