Early initiation of antiretroviral therapy and associated reduction in mortality, morbidity and defaulting in a nurse-managed, community cohort in Lesotho.

INTRODUCTION: The latest WHO guidelines recommend initiating antiretroviral therapy (ART) at CD4 cell counts less than 350 cells/μl. However, donors and national governments are reluctant to support implementation owing to uncertainty regarding feasibility and relative benefit. Lesotho has supported earlier initiation since 2008. We assessed outcomes comparing early (CD4 cell counts >200 cells/μl) and late (CD4 cell counts ≤200 cells/μl) initiation. METHODS: We describe survival probability among patients initiating ART at CD4 cell counts 200 or less and more than 200 cells/μl and assess associations between baseline CD4 cell counts and mortality, morbidity, loss to follow-up and hospitalization using Cox regression adjusting for confounders identified a priori. RESULTS: Our analysis included 1177 patients; median age was 38 years and the majority (67%) were women. Median time on ART for the overall cohort was 506 days (interquartile range 396-608). Five hundred and thirty eight patients initiated ART at a CD4 cell count 200 cells/μl or less (interquartile range 54-160) and 639 patients initiated at CD4 cell count more than 200 cells/μl (interquartile range 238-321). In multivariate analysis, we found that patients initiating at CD4 cell count more than 200 cells/μl were 68% less likely to die (adjusted hazard ratio 0.32, 95% confidence interval 0.20-0.50), and 39% less likely to be lost to follow-up (adjusted hazard ratio 0.61, 95% confidence interval 0.43-0.87). Initiating ART at CD4 cell count more than 200 cells/μl was also associated with a 27% reduction in the rate of incident morbidity (adjusted hazard ratio 0.73, 95% confidence interval 0.65-0.82) and a 63% decreased rate of hospitalization (adjusted hazard ratio 0.37, 95% confidence interval 0.19-0.73). CONCLUSION: Earlier initiation is feasible in a low resource, high HIV prevalence setting, and provides important benefits in terms of reduced mortality, morbidity, retention and hospitalization. Donors should fully support the implementation of the latest WHO recommendations

Centralized prevention of denial of service attacks

The world has come to depend on the Internet at an increasing rate for communication, e-commerce, and many other essential services. As such, the Internet has become an integral part of the workings of society at large. This has lead to an increased vulnerability to remotely controlled disruption of vital commercial and government operations---with obvious implications. This disruption can be caused by an attack on one or more specific networks which will deny service to legitimate users or an attack on the Internet itself by creating large amounts of spurious traffic (which will deny services to many or all networks). Individual organizations can take steps to protect themselves but this does not solve the problem of an Internet wide attack. This thesis focuses on an analysis of the different types of Denial of Service attacks and suggests an approach to prevent both categories by centralized detection and limitation of excessive packet flows