Tuberculosis Treatment Outcomes and Interruption among Patients Assessing Dots Regimen in a Tertiary Hospital in Semi-Urban Area of South-Western Nigeria

BackgroundTuberculosis remains one of the most infectious diseases worldwide especially with the HIV pandemic. It is a cause of high morbidity andmortality in developing countries including Nigeria. Reasons contributing to high morbidity and mortality include high defaulting rate and treatment interruption. Several studies had evaluated the treatment outcome of tuberculosis but there is paucity of published literature on the outcome of treatment interruption especially in this environment. This study thus assessed the outcome of treatments and interruption among patients assessing DOTS regimen in a tertiary hospital located in a semi urban area in south-western Nigeria.MethodologyThe study was a review of TB register of the federal medical centre,Owo from its inception in 2008 to 2011. All the patients that have completed at least one course of chemotherapy (defined as 8 months of  anti-tuberculosis treatment- 2months intensive phase and 6 months continuation phase) were included. Treatment outcome and interruption were defined in accordance with World Health Organisation (WHO) recommendations. Data were analysed with SPSS version 17.ResultsA total of 400 patients were included. The mean age of patients was 36.8 ± 16.8 years and 56.3% were male. Majority, (79.7%) were adults aged 19-64 years, 12.5% were in the paediatric age group and 7.8% were  elderly. Less than half, 45.3% had TB/HIV co-infection. Regarding treatment outcome of tuberculosis, 75.5% were cured, 14.8% died, 4%  relapsed and 3% defaulted. A little above one-fifth, 21 (5.3%) hadtreatment interruption among whom 9 (42.9%) were successfully traced and completed treatment. Significantly, higher proportion of those that had treatment interruption died, 54.1% compared with their counterpart, 14.9%, (p<0.001) and had relapse. (14.3% versus 3.4%, p = 0.01).ConclusionA high rate of tracking failure among patients with treatment interruption was found in the study. In addition, mortality and morbidity were higher among patients with treatment interruption. A more concerted effort is needed in tracking / tracing patients with treatment interruption in order to reduce morbidity and mortality among TB patients assessing treatment

A conceptual model for understanding rainfall variability in the West African Sahel on interannual and interdecadal timescale

This article describes and validates a new conceptual model for understanding Sahel rainfall variability. This conceptual model provides a framework that can readily incorporate and synthesize the roles played by the oceans, the African landmass and local meteorological factors. The most important local factors are the location of the African Easterly Jet (AEJ) and the associated shears. The position of the AEJ helps to distinguish between a wet mode and a dry mode in the Sahel, while other factors determine which of two spatial patterns prevail during years of the dry regime. We test the paradigm by contrasting selected circulation parameters for the years 1958-1967 (representing the wet mode) and 1968-1997 (representing the dry mode). In doing so, we have identified several changes in the general atmospheric circulation that have accompanied the shift to drier conditions. The AEJ is further southward and more intense, the Inter-tropical Convergence Zone (ITCZ) is further south, the Tropical Easterly Jet (TEJ) is weaker, the equatorial westerlies are shallower and weaker, the southwesterly monsoon flow is weaker, and the relative humidity is lower (but not consistently so). The results of this study suggest that the key factor controlling the occurrence of the wet Sahel mode versus the dry mode is the presence of deep, well-developed equatorial westerlies. These displace the AEJ northward into Sahelian latitudes and increase the shear instabilities. The westerlies appear to be at least partially responsible for the well-known association between a weaker AEJ and wetter conditions in the Sahel, because the thermal wind induced by the Sahara/Atlantic temperature gradient is imposed upon a westerly basic state. Since one of the strongest contrasts between the wet Sahel and dry Sahel modes is the strength of the TEJ, the TEJ probably also plays a pivotal role in rainfall variability. In the dry mode, the equatorial westerlies are poorly developed and the core of the AEJ lies well to the south of the Sahel. The dry mode consists of two basic spatial patterns, depending on whether the Guinea Coast Region is anomalously wet or dry (the well-known dipole and no-dipole patterns, respectively). Which occurs is determined by other factors acting to reduce the intensity of the rainbelt. One of the relevant factors appears to be sea-surface temperatures (SSTs) in the Gulf of Guinea