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For centuries, tuberculosis, which is a chronic infection caused by the bacillus Mycobacterium tuberculosis has remained a global health problem. The global burden of tuberculosis has increased, particularly in the Southern African region, mainly due to HIV, and inadequate health systems which has in turn given rise to emergent drug resistant tuberculosis (TB) strains. Bovine tuberculosis (BTB) has also emerged as a significant disease with the tendency for inter-species spread. The extent of interspecies BTB transmission both in urban and rural communities has not been adequately assessed. The phenomenon is of particular importance in rural communities where people share habitats with livestock and wildlife (particularly in areas near national parks and game reserves). Aerosol and oral intake are the major routes of transmission from diseased to healthy individuals, with health care workers often contracting infection nosocomially. Although TB control has increasingly been achieved in high-income countries, the disease, like other poverty-related infections, has continued to be a disaster in countries with low income economies. Transmission of infections occurs not only amongst humans but also between animals and humans (and occasionally vice versa) necessitating assessment of the extent of transmission at their interface. This review explores tuberculosis as a disease of humans which can cross-transmit between humans, livestock and wildlife. The review also addresses issues underlying the use of molecular biology, genetic sequencing and bioinformatics as t tools to understand the extent of inter-species cross-transmission of TB in a 'One Health' context. [ABSTRACT FROM AUTHOR]

Infectious diseases account for nearly 40% of the burden of human mortality and morbidity in low-income countries, of which 7% is attributable to zoonoses and 13% to recently emerging diseases from animals. One of the strategic approaches for effective surveillance, monitoring and control of infectious diseases compromising health in both humans and animals could be through a combination of multiple disciplines. The approach can be achieved through a joint effort from stakeholders comprising health professionals (medical and veterinary), social, economic, agricultural, environmental and other interested parties. With resource scarcity in terms of number of staff, skills and facility in low-income countries, participatory multi-sectoral and multidisciplinary approaches in limiting the burden of zoonotic diseases could be worthwhile. We review challenging issues that may limit the 'One Health' approach for infectious diseases surveillance in Tanzania with a focus on Health Policy and how best the human and animal health systems could be complemented or linked to suit the community in need for disease control under the theme's context. [ABSTRACT FROM AUTHOR]

Despite the apparent public health concern about Bovine tuberculosis (BTB) in Tanzania, little has been done regarding the zoonotic importance of the disease and raising awareness of the community to prevent the disease. Bovine tuberculosis is a potential zoonotic disease that can infect a variety of hosts, including humans. The presence of multiple hosts including wild animals, inefficient diagnostic techniques, absence of defined national controls and eradication programs could impede the control of bovine TB. In Tanzania, the diagnosis of Mycobacterium bovis in animals is mostly carried out by tuberculin skin testing, meat inspection in abattoirs and only rarely using bacteriological techniques. The estimated prevalence of BTB in animals in Tanzania varies and ranges across regions from 0.2% to 13.3%, which is likely to be an underestimate if not confirmed by bacteriology or molecular techniques. Mycobacterium bovis has been detected and isolated from different animal species and has been recovered in 10% of apparently healthy wildebeest that did not show lesions at post-mortem. The transmission of the disease from animals to humans can occur directly through the aerosol route and indirectly by consumption of raw milk. This poses an emerging disease threat in the current era of HIV confection in Tanzania and elsewhere. Mycobacterium bovis is one of the causative agents of human extra pulmonary tuberculosis. In Tanzania there was a significant increase (116.6%) of extrapulmonary cases reported between 1995 and 2009, suggesting the possibility of widespread M. bovis and Mycobacterium tuberculosis infection due to general rise of Human Immunodeficiency virus (HIV). This paper aims to review the potential health and economic impact of bovine tuberculosis and challenges to its control in order to safeguard human and animal population in Tanzania. [ABSTRACT FROM AUTHOR]

In-depth interviews regarding health seeking behaviour were conducted with 202 adults registered with pulmonary tuberculosis at the centralized Chest Clinic in Lusaka, Zambia. The median (mean) diagnostic delay was 8.6 (9) weeks, and was significantly associated with the following factors: female sex, lower education, more than six instances of health-seeking encounters, outpatient diagnosis of tuberculosis, and visiting a private doctor or traditional healer. More effective tuberculosis control interventions require novel methods of accessing women and less educated people. Decentralization of public tuberculosis care and improved integration with private sector health providers may also reduce diagnostic delay. [ABSTRACT FROM AUTHOR]

The polymerase chain reaction (PCR) was evaluated in a trial which, with respect to the positive-to-negative ratio, approximated the situation of a diagnostic laboratory in a tuberculosis-endemic area. Three hundred sputum samples were included in the study, of which one-third were known to contain mycobacteria as judged by direct microscopy. The repetitive insertion sequence IS 6110/IS 986 of Mycobacterium tuberculosis was used as a target. The samples were spiked with DNA from a modified IS 6110/IS 986 sequence, which gives rise to PCR products easily distinguished from PCR products amplified from chromosomal Mycobacterium tuberculosis DNA. This allowed identification of samples that contained substances inhibitory to the Taq polymerase. The detection limit of the assay was 0.05 pg to 0.5 pg of purified Mycobacterium tuberculosis DNA, corresponding to 10 to 100 organisms. The sensitivity and specificity of the PCR was compared with that of conventional microscopy and culture. It was concluded that this method is fast and sensitive, but that culture currently is crucial for assessing viability and thus infectivity. [ABSTRACT FROM AUTHOR]

Nebulised pentamidine was used to treat 30 patients with Pneumocystis carinii pneumonia. Fourteen patients (group 1) received pentamidine isethionate 4 mg/kg (six patients) or 8 mg/kg (eight patients) via a standard jet nebuliser (Acorn, system 22) with a flow rate of 8 l/min. The aerosol droplets had a mass median aerodynamic diameter of 2.6 microns (geometric standard deviation (GSD) 2.9) and 46% of droplets were less than 3.9 microns. A further 16 patients (group 2) received 8 mg/kg pentamidine via a jet nebuliser with baffles to limit droplet size to below 4 microns (Respirgard II). This generated aerosol droplets with a mass median aerodynamic diameter of 0.8 micron (GSD 1.5) and 98% were less than 3.9 microns. Only three of the 14 patients in group 1 responded clinically to treatment, one after the lower dose of pentamidine. Treatment was discontinued in 10 patients and one patient died at bronchoscopy from haemorrhage. Thirteen of the 16 patients in group 2 responded. Side effects occurred infrequently; two patients from group 1 had a cough, six patients (four from group 2) had contact bleeding at bronchoscopy, and two further patients had haemoptysis. The differing response rate may be due to differences in the mean droplet size of the aerosols produced by the nebulisers. Nebulised pentamidine (8 mg/kg) when delivered by Respirgard II nebuliser appears to be as effective as conventional treatment for Pneumocystis carinii pneumonia of mild to moderate severity. [ABSTRACT FROM PUBLISHER]

The value of transbronchial biopsy and bronchoalveolar lavage was assessed in the diagnosis of pulmonary disease in patients infected with the human immunodeficiency virus (HIV). Seventy four transbronchial biopsy and 66 bronchoalveolar lavage specimens (60 paired specimens) from 80 examinations in 64 patients were reviewed. Pneumocystis carinii was the most common pathogen isolated (43 patients). Bronchoalveolar lavage was superior to transbronchial biopsy for the diagnosis of this pathogen, the sensitivities being 90% and 56%. Cytomegalovirus was identified three times by lavage and once by transbronchial biopsy. Neither method detected Kaposi's sarcoma in the one patient shown to have it by open lung biopsy. The complication rate in a concurrent study of bronchoscopy with transbronchial biopsy in 74 consecutive HIV positive patients was 22%. This study does not support the use of transbronchial biopsy in these patients. [ABSTRACT FROM PUBLISHER]