Who infects whom? Social networks and tuberculosis transmission in wild meerkats

Transmission of infectious diseases is strongly influenced by who contacts whom. Despite the global distribution of tuberculosis (TB) in free-living wild mammal populations, little is known of the mechanisms of social transmission of Mycobacterium bovis between individuals. Here, I use a network approach to examine for correlations between five distinct types of intra- and intergroup social interaction and changes in TB status of 110 wild meerkats (Suricata suricatta) in five social groups over two years. Contrary to predictions, the most socially interactive animals were not at highest risk of acquiring infection, indicating that in addition to contact frequency, the type and direction of interactions must be considered when quantifying disease risk. Within social groups, meerkats that groomed others most were more likely to become infected than individuals who received high levels of grooming. Conversely, receiving, but not initiating, aggression was associated with M. bovis infection. Incidence of intergroup roving by male meerkats was correlated with the rovers themselves subsequently testing TB-positive, suggesting a possible route for transmission of infection between social groups. Exposure time was less important than these social interactions in influencing TB risk. This study represents a novel application of social network analysis using empirical data to elucidate the role of specific interactions in the transmission of an infectious disease in a free-living wild animal population.     

Is tuberculosis taken seriously in the United Kingdom?

Tuberculosis has been the subject of much concern in recent years. Notifications have increased, inadequacies in surveillance revealed, and policies for BCG immunisation and screening of immigrants questioned. Until recently the disease was given low priority in the United Kingdom. There is no overall strategic framework for tackling tuberculosis, and fears have been expressed about the future of local tuberculosis control programmes in the new market economy of the NHS. An action plan for tuberculosis within the context of a national programme is urgently required. Only then will a major impact on the incidence of the disease be seen.     

Who does all the research in conservation biology?

Much of the worlds biodiversity is located within countries with developing economies. We therefore examine how well developing nations and their scientists are represented in three international conservation biology journals (Conservation Biology, Biological Conservation, Biodiversity and Conservation). We found: (1) that 28% of studies were from lower income countries and only 15% of all papers had primary authors from these nations. Of papers from lower income countries, although 80% had at least one local author, only 47% had primary authors from the country where the study was conducted. (2) Lower income countries had more research with a strong applied focus compared to research from high-income countries. (3) In lower income countries research was often funded by international sources but the primary authors of these studies were from affluent nations. (4) The three journals differed in how well they represented lower income nations and their scientists, reflecting their editorial policies for including research from lower income nations. The main reason for the large discrepancy in a countrys output of conservation research is due to the difference in a nations ability to invest in science. However, a brief survey of authors suggests that there is a large amount of information available in lower income and non-English speaking countries that is not easily accessible to the international conservation community. Journals may therefore need to consider altering their policies if we are to improve the representation of research by scientists in lower income nations.     

Who are the Kuchi? Nomad self-identities in Afghanistan

'Kuchi', an Afghan Persian word meaning 'those who go on migrations', is the common generic term, used by both Afghans and foreigners, for the nomads of Afghanistan, as it has been for many decades. Most if not all the nomads, and indeed many long-settled former nomads, now acknowledge this name, yet in the 1960s and 1970s few of those so labelled used the term for themselves. This article examines the usage of both 'Kuchi' and 'nomad', and locates them in the wider contexts of ethnic labelling practices in Afghanistan, anthropological debates about pastoral nomadism, and government-nomad relations in both Afghanistan and neighbouring Iran.  

Résumé

« Kuchi >>, un mot farsi d'Afghanistan désignant « ceux qui migrent >>, est le nom générique donné depuis des dizaines d'années par les Afghans, aussi bien que par les étrangers, aux nomades d'Afghanistan. Alors qu'aujourd'hui, la plupart de ces nomades, sinon tous, ainsi d'ailleurs que beaucoup d'anciens nomades sédentarisés depuis longtemps, se réclament de ce nom, ils étaient peu nombreux à se désigner ainsi dans les années 1960 et 1970. L'auteur examine ici l'usage des mots « Kuchi >> et « nomades >> et les resitue dans le contexte plus large des pratiques de dénomination ethniques en Afghanistan, des débats anthropologiques sur le nomadisme pastoral et des relations entre gouvernement et nomades en Afghanistan et dans l'Iran voisin.     

Who owns the data?

About ten years ago, a group of scientists began to argue that it was unfair to ask other scientists to pay to read the results of research that had been publicly funded.     

Is Mycobacterium bovis in the environment important for the persistence of bovine tuberculosis?

Mycobacterium bovis is the causative agent of bovine tuberculosis (bTB) in cattle and wildlife. Direct aerosol contact is thought to be the primary route of infection between conspecifics, whereas indirect transmission via an environmental reservoir of M. bovis is generally perceived not to be a significant source for infection. Here, we report on the application of molecular technology (PCR) to quantify the prevalence of M. bovis in the environment and to explore its epidemiological significance. We show that the detectability of viable M. bovis at badger setts and latrines is strongly linked to the frequency of M. bovis excretion by infected badgers, and that putative M. bovis in the environment is prevalent on a large proportion of endemic cattle farms in Britain. These results raise important questions about the role of an environmental reservoir in bTB persistence.     

Who owns the Brazilian carbon?

Brazil is one of the major contributors to land‐use change emissions, mostly driven by agricultural expansion for food, feed, and bioenergy feedstock. Policies to avoid deforestation related to private commitments, economic incentives, and other support schemes are expected to improve the effectiveness of current command and control mechanisms increasingly. However, until recently, land tenure was unknown for much of the Brazilian territory, which has undermined the governance of native vegetation and challenged support and incentive mechanisms for avoiding deforestation. We assess the total extent of public governance mechanisms protecting aboveground carbon (AGC) stocks. We constructed a land tenure dataset for the entire nation and modeled the effects and uncertainties of major land‐use acts on protecting AGC stocks. Roughly 70% of the AGC stock in Brazil is estimated to be under legal protection, and an additional 20% is expected to be protected after areas in the Amazon with currently undesignated land undergo a tenure regularization. About 30% of the AGC stock is on private land, of which roughly two‐thirds are protected. The Cerrado, Amazon, and Caatinga biomes hold about 40%, 30%, and 20% of the unprotected AGC, respectively. Effective conservation of protected and unprotected carbon will depend on successful implementation of the Forest Act, and regularization of land tenure in the Amazon. Policy development that prioritizes unprotected AGC stocks is warranted to promote conservation of native vegetation beyond the legal requirements. However, different biomes and land tenure structures may require different policy settings considering local and regional specifics. Finally, the fate of current AGC stocks relies upon effective implementation of command and control mechanisms, considering that unprotected AGC in native vegetation on private land only accounts for 6.5% of the total AGC stock.     

Who cares for the protons?

It is tempting to use standard protonation states for the analysis of protein-ligand interactions. Two different pK(a) calculation methods, PROPKA (protein pK(a)) and MCCE (multi conformation continuum electrostatics), were applied to challenge this convenient behavior. As data basis, we selected five recently approved drugs for which structural information of the protein-drug complex is available. We analyzed the pK(a) calculations in terms of a measure termed BIPS (binary protonation states) recently introduced by us. Both methods agree in detecting the majority of the sites with atypical BIPS values. However, when using only one method, some of the atypcial BIPS value would have been missed. Therefore, we recommend using both methods to set such an interpretation on a solid basis.     

Who speaks for the dispossessed?

This commentary articulates three perspectives on race in America: economic determinism, institutionalism and a field-theoretic approach. It argues that William Julius Wilson's masterwork, The Declining Significance of Race, was informed by the first and anticipated the latter two. Wilson's most profound and enduring legacy is his unwavering concern for the dispossessed.     

Exosomes in tuberculosis: Still terra incognita?

Today, diagnosis, vaccination, and treatment of tuberculosis (TB) remain major clinical challenges. Therefore, an introduction of new diagnostic measures and biomarkers is necessary to improve infection control. The ideal biomarker for TB infection can be defined as a host or pathogen-derived biomolecule, which is potent for identifying infection and determining its clinical stage. Exosomes, defined as cell-derived nanovesicles released into biological fluids, are involved in cell–cell communication and immune modulation. These vesicles have emerged as a new platform for improving the clinical diagnosis and prognosis of different infectious diseases and cancers. The role of these nanovehicles, as alternative biomarkers for the improvement of TB diagnosis and treatment, has been demonstrated in a significant body of literature. In this review, we summarized recent progress in the clinical application of exosome-based biomarkers in TB infection.     

Multi-Morbidity in Hospitalised Older Patients: Who Are the Complex Elderly?

Background

No formal definition for the “complex elderly” exists; moreover, these older patients with high levels of multi-morbidity are not readily identified as such at point of hospitalisation, thus missing a valuable opportunity to manage the older patient appropriately within the hospital setting.

Objectives

To empirically identify the complex elderly patient based on degree of multi-morbidity.

Design

Retrospective observational study using administrative data.

Setting

English hospitals during the financial year 2012–13.

Subjects

All admitted patients aged 65 years and over.

Methods

By using exploratory analysis (correspondence analysis) we identify multi-morbidity groups based on 20 target conditions whose hospital prevalence was ≥ 1%.

Results

We examined a total of 2788900 hospital admissions. Multi-morbidity was highly prevalent, 62.8% had 2 or more of the targeted conditions while 4.7% had six or more. Multi-morbidity increased with age from 56% (65-69yr age-groups) up to 67% (80-84yr age-group). The average multi-morbidity was 3.2±1.2 (SD). Correspondence analysis revealed 3 distinct groups of older patients. Group 1 (multi-morbidity ≤2), associated with cancer and/or metastasis; Group 2 (multi-morbidity of 3, 4 or 5), associated with chronic pulmonary disease, lung disease, rheumatism and osteoporosis; finally Group 3 with the highest level of multi-morbidity (≥6) and associated with heart failure, cerebrovascular accident, diabetes, hypertension and myocardial infarction.

Conclusions

By using widely available hospital administrative data, we propose patients in Groups 2 and 3 to be identified as the complex elderly. Identification of multi-morbidity patterns can help to predict the needs of the older patient and improve resource provision.