Fine particulate matter (PM2.5) has been linked to cardiovascular disease, possibly via accelerated atherosclerosis. We examined associations between the progression of the intima-medial thickness (IMT) of the common carotid artery, as an indicator of atherosclerosis, and long-term PM2.5 concentrations in participants from the Multi-Ethnic Study of Atherosclerosis (MESA).

Stigma, discrimination, lack of privacy, and long waiting times partly explain why six out of ten individuals living with HIV do not access facility-based testing. By circumventing these barriers, self-testing offers potential for more people to know their sero-status. Recent approval of an in-home HIV self test in the US has sparked self-testing initiatives, yet data on acceptability, feasibility, and linkages to care are limited.

Increasing attention is being paid to the subject of air pollution, with the bulk of previous work being done in animal models suggesting that exposure to air pollution causes atherosclerosis—stiffening and calcification of the arteries—in rabbits and mice. The findings of Sara Adar and colleagues, published in PLOS Medicine, take us a step forward in clarifying the broader implications of air pollution by offering further evidence in humans that ambient particulate matter (PM) contributes to the development of cardiovascular disease (CVD).

In an evaluation of medicines approved by the European Medicines Agency 2000 to 2010, Ruben Duijnhoven and colleagues find that the number of patients evaluated for medicines approved for chronic use are inadequate for evaluation of safety or long-term efficacy.

As participant-led health research increases, Effy Vayena and and John Tasioulas examine what ethical questions are raised, and what types of standards need to be developed for appropriate ethical oversight for participant-led research projects.

Shingai Machingaidze and colleagues reflect on the successes and shortfalls of the Expanded Programme on Immunization (EPI) in Africa, and the considerable challenges that must now be addressed to improve immunization systems.

Roman Carrasco and colleagues propose a "cap and trade" system for global health involving a cost-effectiveness criterion and a DALY (Disability-Adjusted Life Year) global credit market, mirroring global carbon emission permits trading markets to mitigate climate change.

Patricia McGettigan and David Henry find that, although some non-steroidal anti-inflammatory drugs (NSAIDs) such as diclofenac are known to increase cardiovascular risk, diclofenac is included on 74 countries’ essential medicine lists and was the most commonly used NSAID in the 15 countries they evaluated.

K. Srinath Reddy and Ambuj Roy discuss the Research Article by Patricia McGettigan and David Henry about the continued use of NSAIDs associated with increased risk of cardiovascular disease, including the mechanisms of increased risk, probable reasons for ongoing use, and next steps.

Sub-Saharan Africa (SSA) has contributed the least of any world region to the global accumulation of greenhouse gas emissions; however, this region will probably be more vulnerable to the impacts of climate change than any other. Less than 7% of the world's total emissions of greenhouse gases emanate from the African continent; thus the continent contributes very little overall to climate change.