Zoonotic Tuberculosis – The Changing Landscape

Despite slow reductions in the annual burden of active human tuberculosis (TB) cases, zoonotic TB (zTB) remains a poorly monitored and an important unaddressed global problem. There is a higher incidence in some regions and countries, especially where close association exists between growing numbers of cattle (the major source of Mycobacterium bovis) and people, many suffering from poverty, and where dairy products are consumed unpasteurised. More attention needs to be focused on possible increased zTB incidence resulting from growth in dairy production globally and increased demand in low income countries in particular. Evidence of new zoonotic mycobacterial strains in South Asia and Africa (e.g. M. orygis), warrants urgent assessment of prevalence, potential drivers and risk in order to develop appropriate interventions. Control of M. bovis infection in cattle through detect and cull policies remain the mainstay of reducing zTB risk, whilst in certain circumstances animal vaccination is proving beneficial. New point of care diagnostics will help to detect animal infections and human cases. Given the high burden of human tuberculosis (caused by M. tuberculosis) in endemic areas, animals are affected by reverse zoonosis, including multi-drug resistant strains. This, may create drug resistant reservoirs of infection in animals. Like COVID-19, zTB is evolving in an ever-changing global landscape

Interventions to improve exercise behaviour in sedentary people living with and beyond cancer: a systematic review

Background: To systematically review the effects of interventions to improve exercise behaviour in sedentary people living with and beyond cancer. Methods: Only randomised controlled trials (RCTs) that compared an exercise intervention to a usual care comparison in sedentary people with a homogeneous primary cancer diagnosis, over the age of 18 years were eligible. The following electronic databases were searched: Cochrane Central Register of Controlled Trials MEDLINE; EMBASE; AMED; CINAHL; PsycINFO; SportDiscus; PEDro from inception to August 2012. Results: Fourteen trials were included in this review, involving a total of 648 participants. Just six trials incorporated prescriptions that would meet current recommendations for aerobic exercise. However, none of the trials included in this review reported intervention adherence of 75% or more for a set prescription that would meet current aerobic exercise guidelines. Despite uncertainty around adherence in many of the included trials, the interventions caused improvements in aerobic exercise tolerance at 8–12 weeks (SMD=0.73, 95% CI=0.51–0.95) in intervention participants compared with controls. At 6 months, aerobic exercise tolerance is also improved (SMD=0.70, 95% CI=0.45–0.94), although four of the five trials had a high risk of bias; hence, caution is warranted in its interpretation. Conclusion: Expecting the majority of sedentary survivors to achieve the current exercise guidelines is likely to be unrealistic. As with all well-designed exercise programmes, prescriptions should be designed around individual capabilities and frequency, duration and intensity or sets, repetitions, intensity of resistance training should be generated on this basis

Systematic review of the validity and reliability of consumer-wearable activity trackers

Abstract Background Consumer-wearable activity trackers are electronic devices used for monitoring fitness- and other health-related metrics. The purpose of this systematic review was to summarize the evidence for validity and reliability of popular consumer-wearable activity trackers (Fitbit and Jawbone) and their ability to estimate steps, distance, physical activity, energy expenditure, and sleep. Methods Searches included only full-length English language studies published in PubMed, Embase, SPORTDiscus, and Google Scholar through July 31, 2015. Two people reviewed and abstracted each included study. Results In total, 22 studies were included in the review (20 on adults, 2 on youth). For laboratory-based studies using step counting or accelerometer steps, the correlation with tracker-assessed steps was high for both Fitbit and Jawbone (Pearson or intraclass correlation coefficients (CC) > =0.80). Only one study assessed distance for the Fitbit, finding an over-estimate at slower speeds and under-estimate at faster speeds. Two field-based studies compared accelerometry-assessed physical activity to the trackers, with one study finding higher correlation (Spearman CC 0.86, Fitbit) while another study found a wide range in correlation (intraclass CC 0.36–0.70, Fitbit and Jawbone). Using several different comparison measures (indirect and direct calorimetry, accelerometry, self-report), energy expenditure was more often under-estimated by either tracker. Total sleep time and sleep efficiency were over-estimated and wake after sleep onset was under-estimated comparing metrics from polysomnography to either tracker using a normal mode setting. No studies of intradevice reliability were found. Interdevice reliability was reported on seven studies using the Fitbit, but none for the Jawbone. Walking- and running-based Fitbit trials indicated consistently high interdevice reliability for steps (Pearson and intraclass CC 0.76–1.00), distance (intraclass CC 0.90–0.99), and energy expenditure (Pearson and intraclass CC 0.71–0.97). When wearing two Fitbits while sleeping, consistency between the devices was high. Conclusion This systematic review indicated higher validity of steps, few studies on distance and physical activity, and lower validity for energy expenditure and sleep. The evidence reviewed indicated high interdevice reliability for steps, distance, energy expenditure, and sleep for certain Fitbit models. As new activity trackers and features are introduced to the market, documentation of the measurement properties can guide their use in research settings

Molecular analysis of human and bovine tubercle bacilli from a local setting in Nigeria

To establish a molecular epidemiological baseline for the strains causing tuberculosis in Nigeria, a survey of isolates from humans and cattle was carried out. Spoligotyping and variable-number tandem-repeat analysis revealed that the majority of tuberculosis disease in humans in Ibadan, southwestern Nigeria, is caused by a single, closely related group of Mycobacterium tuberculosis strains. Using deletion typing, we show that approximately 13% of the disease in humans in this sample was caused by strains of Mycobacterium africanum and Mycobacterium bovis rather than M. tuberculosis. Molecular analysis of strains of M. bovis recovered from Nigerian cattle show that they form a group of closely related strains that show similarity to strains from neighboring Cameroon. Surprisingly, the strains of M. bovis recovered from humans do not match the molecular type of the cattle strains, and possible reasons for this are discussed. This is the first molecular analysis of M. tuberculosis complex strains circulating among humans and cattle in Nigeria, the results of which have significant implications for disease control

The burden of transboundary animal diseases and implications for health policy

In Sahelian Africa and connected regions, the burden of transboundary animal diseases is poorly understood. This is due in part to the lack of robust estimates of the distribution and intensity of these diseases within the region. However, the problem is compounded by the complexity of the types of losses attributable to specific diseases, including the impact on human health of zoonotic transboundary diseases such as brucellosis and Rift Valley fever. There is also a balance between disease losses and the cost of our response to the presence or perceived threat of transboundary animal diseases. This chapter presents a framework for measuring the burden of transboundary animal diseases in the Sahel region, explores disease distribution data and collates what information is available on productivity losses and expenditure on disease mitigation, namely surveillance, prevention, control and treatment activities. We highlight the need for standardised data collection processes that capture disease loss estimates as well as expenditure related to our response. Reporting changes in losses and expenditure over time will provide a basis for making informed disease control policies for transboundary animal diseases. The outcome of this will be an evidence-base for mobilising resources in an efficient and effective manner