Quality of the guidelines for preparation and review of environmental impact assessment reports in Pakistan

Environmental impact assessment (EIA) is an important tool for making informed decisions about development projects to avoid or mitigate potential adverse impacts on the environment. Guidelines are prepared all over the world to facilitate consultants and stakeholders to meet the objectives of EIA and to prepare quality EIA reports. The Pakistan Environmental Protection Agency prepared environmental impact assessment guidelines for this purpose in 1997. However, the major issue is that, even after two decades, the guidelines have not been reviewed. This paper presents the outcome of research conducted on the contents and quality of the guidelines for the preparation of EIA reports. The methodology encompasses an extensive review of the literature as well as available guidelines and interviews with the selected consultants, using semi-structured interview schedules. Although the quality of current guidelines overall is found to be good, the likelihood they are followed is connected with them being updated regularly, taking on board opinion of EIA consultants and other stakeholders.     

Assessing the impact of adherence to anti-retroviral therapy on treatment failure and resistance evolution in HIV

The adherence of patients to therapy is a crucial factor for successful HIV anti-retroviral therapy. Imperfect adherence may lead to treatment failure, which can cause the emergence of resistance within viral populations. We have developed a stochastic model that incorporates compartments of latently infected cells and virus genotypes with different susceptibilities to three simultaneously used drugs. With this model, we study the impact of several key parameters on the probability of treatment failure, i.e. insufficient viral suppression, and the emergence of resistance. Specifically, we consider the impact of drug dosage, drug half-lives, fitness costs for resistance, different basic reproductive numbers of the virus and the influence of pre-existing mutations under various levels of adherence. Furthermore, we also investigate the influence of different temporal distributions of non-adherent days (drug holidays) during a treatment. Factors that promote resistance evolution include a high reproductive number, extended drug holidays and poor adherence. Pre-existing mutations only have a substantial effect if they confer resistance against more than one drug. Overall, our study highlights the importance of the interactions between imperfect adherence, pharmacodynamics, pharmacokinetics and latently infected cells for our understanding of drug resistance and therapy failure in HIV anti-retroviral therapy.