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IntroductionThe risk of progression to tuberculosis disease is highest within the first year after M. tuberculosis infection (TBI). We hypothesize that people with newly acquired TBI have a unique cytokine/chemokine profile that could be used as a potential biomarker.MethodsWe evaluated socio-demographic variables and 18 cytokines/chemokines in plasma samples from a cohort of people deprived of liberty (PDL) in two Colombian prisons: 47 people diagnosed with pulmonary TB, 24 with new TBI, and 47 non-infected individuals. We performed a multinomial regression to identify the immune parameters that differentiate the groups.ResultsThe concentration of immune parameters changed over time and was affected by the time of incarceration. The concentration of sCD14, IL-18 and IP-10 differed between individuals with new TBI and short and long times of incarceration. Among people with short incarceration, high concentrations of MIP-3α were associated with a higher risk of a new TBI, and higher concentrations of Eotaxin were associated with a lower risk of a new TBI. Higher concentrations of sCD14 and TNF-α were associated with a higher risk of TB disease, and higher concentrations of IL-18 and MCP-1 were associated with a lower risk of TB disease.ConclusionsThere were cytokines/chemokines associated with new TBI and TB disease. However, the concentration of immune mediators varies by the time of incarceration among people with new TBI. Further studies should evaluate the changes of these and other cytokines/chemokines over time to understand the immune mechanisms across the spectrum of TB.

IntroductionIn the early days of the COVID-19 pandemic there were numerous stories of health equity work being put “on hold” as public health staff were deployed to the many urgent tasks of responding to the emergency. Losing track of health equity work is not new and relates in part to the need to transfer tacit knowledge to explicit articulation of an organization’s commitment to health equity, by encoding the commitment and making it visible and sustainable in policy documents, protocols and processes.MethodsWe adopted a Theory of Change framework to develop training for public health personnel to articulate where and how health equity is or can be embedded in their emergency preparedness processes and documents.ResultsOver four sessions, participants reviewed how well their understanding of disadvantaged populations were represented in emergency preparedness, response and mitigation protocols. Using equity prompts, participants developed a heat map depicting where more work was needed to explicitly involve community partners in a sustained manner. Participants were challenged at times by questions of scope and authority, but it became clear that the explicit health equity prompts facilitated conversations that moved beyond the idea of health equity to something that could be codified and later measured. Over four sessions, participants reviewed how well their understanding of disadvantaged populations were represented in emergency preparedness, response and mitigation protocols. Using equity prompts, participants developed a heat map depicting where more work was needed to explicitly involve community partners in a sustained manner. Participants were challenged at times by questions of scope and authority, but it became clear that the explicit health equity prompts facilitated conversations that moved beyond the idea of health equity to something that could be codified and later measured.DiscussionUsing the indicators and prompts enabled the leadership and staff to articulate what they do and do not know about their community partners, including how to sustain their involvement, and where there was need for action. Saying out loud where there is – and is not – sustained commitment to achieving health equity can help public health organizations move from theory to true preparedness and resilience.

BackgroundThe World Health Organization (WHO) End TB strategy document ‘Toward tuberculosis elimination: an action framework for low incidence countries'—like Canada— identifies screening and treatment of latent tuberculosis infection (LTBI) for groups at increased risk for TB disease as a priority, including newcomers from endemic countries. In 2015, the clients-centered model offered at a primary care facility for refugees, BridgeCare Clinic, Winnipeg, Canada was evaluated. The model included LTBI screening, assessment, and treatment, and originally offered 9-months of isoniazid as treatment. This mixed methods evaluation investigates LTBI program outcomes since the introduction of two short-course treatment regimens: 4-months of rifampin, and 3-months of isoniazid and rifapentine.MethodsThis study combined a retrospective analysis of program administrative data with structured interviews of clinic staff. We included LTBI treatment eligibility, the treatment regimen offered, treatment initiation, and completed treatment from January 1, 2015 to August 6, 2020.ResultsSeven hundred and one people were screened, and infection rates varied from 34.1% in 2015 to 53.3% in 2020. Most people living with LTBI came from high TB burden countries in Africa and South-East Asia WHO regions and were younger than 45 years old. Treatment eligibility increased 9% (75% in 2015 to 86% in 2016–2020) and most people diagnosed with LTBI took the short course treatments offered. There was an increase of 14.5% in treatment initiation (75.6 vs. 90.1%), and an increase of 8% in treatment completion (82.4 vs. 90.4%) after short-course regimens were introduced. The final model showed that the treatment regimen tends to affect the frequency of treatment completion, but there are other factors that influence this outcome, in this population. With the new treatments, BridgeCare Clinic achieved the 90% of treatment coverage, and the 90% treatment completion rate targets recommended in the End TB Strategy. Qualitative interviews with clinic staff further affirm the higher acceptability of the new treatments.ConclusionWhile these results are limited to government-sponsored refugees in Winnipeg, they highlight the acceptability and value of short-course LTBI treatment as a possibility for reaching End TB targets in primary care settings.

Immunomodulators such as tumour necrosis factor (TNF) inhibitors are used to treat autoimmune conditions by reducing the magnitude of the innate immune response. Dampened innate responses pose an increased risk of new infections by opportunistic pathogens and reactivation of pre-existing latent infections. The alteration in immune response predisposes to increased severity of infections. TNF inhibitors are used to treat autoimmune conditions such as rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, transplant recipients, and inflammatory bowel disease. The efficacies of immunomodulators are shown to be varied, even among those that target the same pathways. Monoclonal antibody-based TNF inhibitors have been shown to induce stronger immunosuppression when compared to their receptor-based counterparts. The variability in activity also translates to differences in risk for infection, moreover, parallel, or sequential use of immunosuppressive drugs and corticosteroids makes it difficult to accurately attribute the risk of infection to a single immunomodulatory drug. Among recipients of TNF inhibitors, Mycobacterium tuberculosis has been shown to be responsible for 12.5-59% of all infections; Pneumocystis jirovecii has been responsible for 20% of all non-viral infections; and Legionella pneumophila infections occur at 13-21 times the rate of the general population. This review will outline the mechanism of immune modulation caused by TNF inhibitors and how they predispose to infection with a focus on Mycobacterium tuberculosis, Legionella pneumophila, and Pneumocystis jirovecii. This review will then explore and evaluate how other immunomodulators and host-directed treatments influence these infections and the severity of the resulting infection to mitigate or treat TNF inhibitor-associated infections alongside antibiotics.

Background: People living in long-term care facilities (LTCF) are at high risk to develop active tuberculosis primarily as a result of reactivation of a latent TB infection, or endemic transmission between residents. Current national guidelines in Canada are to use a posterior-anterior and lateral chest X-ray to screen for TB for those over 65 years old, upon admission to a LTCF.Objective: To assess the available evidence for cost benefits of universal chest X-ray screening for new LTCF residents.Methodology: We conducted a search for all articles published until September 2018, in PubMed and WorlCat databases, in English, using a combination of key words: chest X-ray, chest radiography or CXR, long-term care, elderly, screening, and tuberculosis. We also reviewed publicly available guidelines for screening new residents to LTCF from across Canada. We report on a qualitative synthesis of the evidence in the documents retrieved.Results: The final review yielded four cost-effectiveness studies (2 of 4 conducted in countries with low incidence), one systematic review, one recommendation/editorial, and one cohort study. We found that in a tuberculosis low-incidence country the CXR cost per identified case was $672,298 CAD. Enacting a more targeted screening program, perhaps one that tests only those who previously had TB, or other high-risk medical conditions may enhance the cost-effectiveness.Recommendations: We suggest reviewing the screening policy for active TB in people entering LTCF, which is based on a CXR. The results indicate that a targeted search for active TB in people with symptoms or other high-risk medical conditions may be more cost-effective.

Although Canada has one of the lowest tuberculosis incidence rates in the world, certain groups are disproportionately affected, including foreign born people from high incidence countries. The Winnipeg Regional Health Authority has initiated a process to decentralize latent tuberculosis infection (LTBI) management at primary care clinics in Winnipeg. One of these clinics is BridgeCare Clinic which provides services to government-assisted refugees. The present study describes the BridgeCare Clinic LTBI program and reviews program outcomes from January 2015 to October 2016. Refugees at BridgeCare Clinic receive comprehensive care, including LTBI screening and treatment. The LTBI program is managed by physicians, nurse practitioners, and primary care nurses under a patient-centered model of care. An accessible interpretation service, education to clients, and laboratory sampling at the clinic with free IGRA testing are important components of the program. Anonymized data on client outcomes were statistically analyzed and qualitative interviews were conducted with senior staff. During the study period, 274 IGRA tests were ordered with 158 negative results (57.7%) and 101 positive results (36.9%). Of 45 clients eligible (from January to December 2015) for LTBI treatment, 11 (24.4%) declined to receive treatment and 34 (75.6%) started treatment. Twenty-seven (79.4%) clients completed treatment, 3 (8.8%) clients moved out of province, and 4 (11.8%) did not complete treatment. The most recent World Health Organization strategy for tuberculosis control calls for integrated, patient-centered care and prevention. Aligned with these WHO recommendations, our experience suggests that LTBI care and treatment can be delivered effectively in a primary care setting using an integrated patient-centered approach.

Many Canadians have had personal experience of a major emergency or disaster at some point in their lifetime and close to a third of those affected were evacuated from their homes or communities. Most evacuations have lasted less than 2 weeks, but in some instances, people have been displaced for months or years. For example, hundreds of residents evacuated following flooding in Lake St. Martin, Manitoba in 2011, remain displaced today. In order to learn more about the roles and responses of public health for long-term evacuees (LTEs) in Canada, we conducted a narrative review of published English-language documents, beginning with literature specific to Canada and then expanding to include literature on other high-income countries. We found that while researchers have explored public health considerations in emergency preparedness, acute disaster management, and resettlement in these contexts there is a dearth of published evidence regarding the public health implications of prolonged evacuation and the public health responses to long-term evacuation in Canada and in other high-income countries. Because the public health needs of diverse populations of LTEs have not been fully investigated, it is likely that they are neither well-understood nor adequately addressed in public health policy and practice.