A/HRC/34/49 environmental microorganisms is “a part of the more global problem of disappearing natural environments and general loss of biodiversity. The ‘far out biodiversity’ (plant and animal life) and the ‘close to biodiversity’ (micro-biotas) are interconnected and shrinking”. 21 The loss of this microbial diversity appears to cause problems of immunoregulation, leading human immune systems to attack the wrong targets, which in turn causes autoimmune diseases, allergic disorders and other non-communicable inflammatory diseases to become more prevalent in all parts of the world. 22 Infectious diseases 16. For some zoonotic diseases,23 the loss of biodiversity has been linked to increased prevalence in humans. “For instance, hantavirus prevalence is thought to increase when mammal diversity decreases; the rise of West Nile virus is correlated with decreases in nonpasserine bird richness; landscape prevalence of Bartonella increases when large wildlife are removed; and habitat fragmentation increases risk of Lyme disease.”24 In such cases, a high diversity of pathogen hosts appears to dilute the transmission paths of pathogens to humans; as diversity decreases, the transmission rates increase.25 Mental health 17. It is increasingly clear that exposure to nature has beneficial effects on mental health. A comprehensive review of studies concluded that “experiencing nature can have positive effects on mental/psychological health, healing, heart rate, concentration, levels of stress, blood pressure, behaviour, and other health factors. For example, viewing nature, even through a window, improves recovery from surgery.” 26 Most of the cited studies examine exposure to green space or natural surroundings without controlling for diversity. However, “there is mounting evidence that not just exposure to nature, but contact with diverse natural habitats and many different species, has important positive impacts for human health”.27 2. Right to an adequate standard of living 18. The Universal Declaration of Human Rights (art. 25) and the International Covenant on Economic, Social and Cultural Rights (art. 11) recognize the right to an adequate standard of living. The Committee on Economic, Social and Cultural Rights has explained that the right to an adequate standard of living is intentionally expansive and that the Covenant includes “a number of rights emanating from, and indispensable for, the realization of the right”.28 These rights include the rights to food and housing, to which the Covenant explicitly refers, and the rights to safe and clean water and sanitation, which have been recognized by the General Assembly, in its resolution 64/292, and the Human Rights Council, in its resolution 15/9. 21 22 23 24 25 26 27 28 Ibid. See also Ilkka Hanski, “Environmental biodiversity, human microbiota, and allergy are interrelated”, Proceedings of the National Academy of Sciences, vol. 109, No. 21 (2012), p. 8334. Connecting Global Priorities, p. 150. Zoonotic diseases are normally found in animals but can infect humans. Connecting Global Priorities, p. 132. Aaron Bernstein, “Biological diversity and public health”, Annual Review of Public Health, vol. 35 (January 2014), pp. 153 and 159. Paul A. Sandifer and others, “Exploring connections”, p. 3. Ibid., p. 6. See also Richard A. Fuller and others, “Psychological benefits of greenspace increase with biodiversity”, Biology Letters, vol. 3 (2007) p. 390; Connecting Global Priorities, pp. 200-209. General comment No. 15 (2002) on the right to water, para. 3. 7