ERS | monograph Preface Tobias Welte, Editor in Chief According to figures from UNAIDS, there were 34.2 million people living with HIV in 2011, a rise of 5.1 million on 2001. Of these, 2.5 million had become newly infected, a reduction of 22% on figures from 2001. 1.7 million people died from AIDS-related causes in 2011, a decline of 11% on the number of AIDS-related deaths in 2001. A similar decrease in new infections was seen amongst neonates and infants: from 570 000 in 2003 (when figures peaked) to 330 000 in 2011. However, it must be acknowledged that these are global figures and they hide a wide diversity in the number of cases and deaths between countries and risk groups. The most affected continent continues to be sub- Saharan Africa, followed by Eastern Europe and the Caribbean, and the following groups are disproportionately affected: men who have sex with men, female sex workers, injecting drug users, truck drivers, fishermen and the military [1]. Tremendous progress has been made during the last decade, not only in preventive measures but also in HIV treatment. 25 antiretroviral drugs have been licensed for HIV treatment and, thanks to international financial aid and a reduction in the price, these drugs are now available in low- and middle-income countries. More than 8 million individuals are now on therapy in low- and middle-income countries, and as a result, the death rate in some of the hardest hit countries has started to decline, following mortality reductions in the USA and Europe in the late nineties. The life expectancy of an HIV-infected individual who is receiving treatment is approaching that of an uninfected individual, although there are side-effects of the treatment that have an influence on quality of life and the ability to work and participate normally in daily life [2]. That said, progress in the treatment of AIDS has led to carelessness, especially in western capitals. Important precautions are being forgotten and a rise in new infections has been observed during recent years. Pulmonary manifestations represent one of the major AIDS complications and are the most life-threatening amongst those Copyright ERS 2014. Print ISBN: 978-1-84984-054-5. Online ISBN: 978-1-84984-055-2. Print ISSN: 2312-508X. Online ISSN: 2312-5098. ERS Monogr 2014 66: vii–viii. DOI: 10.1183/2312508X.10016414 vii