United Nations

This site is maintained by UNEP/GRID-Geneva
Last Update:
We would appreciate
your feedback



Growing disease problems

Infectious diseases are on the rise and now kill 17 million people a year, particularly young people in the developing world. Rising levels of drug resistance are making them more difficult to treat (WHO, 1996a). The concern over new viruses, started with HIV causing AIDS, has been reinforced as other emergent viral diseases have been reported, including Ebola, Hantavirus and Rift Valley Fever. Growing drug resistance, new virulent strains, continuing poverty, the breakdown of public health measures, and increased human contact are leading to renewed outbreaks of other epidemic diseases (WRI/UNEP/UNDP/WB, 1996). Travel and urbanization are increasing human vulnerability to epidemics of both old and emerging diseases (Maurice, 1993; Day, 1996). There is also concern that climate change may have significant effects on health (WHO, 1996b).

Tuberculosis is now the world's single largest cause of death from a single agent, with one third of the population latently infected and 3.1 million deaths in 1995, up 13 percent from the previous year (WHO, 1996a). At the rate TB is spreading, it could claim over 100 million lives over the next 50 years. The association of TB with the AIDS epidemic is one of the main reasons for the increase (Kochi, 1996).

There are presently about 300-500 million clinical cases of malaria a year, 90 percent in Africa, and malaria deaths rose 5 percent in 1995, killing 2.1 million people, mostly children (WHO, 1996a). Global warming could cause another 50-80 million cases as disease-bearing mosquitoes move into new areas (Martin and Lefebvre, 1995; Pearce, 1995a; IPCC, 1995).

Food poisoning and food-borne diseases are also rising rapidly, even in the most developed countries. The incidence in Europe tripled over the last decade, and in the US there may be 24-82 million cases and 10,000 needless deaths from food poisoning annually. Increased environmental contamination, wider exchange of pathogens, and large-scale food processing and preparation are some causes implicated (Maurice, 1994).

Recent increases in solar ultraviolet (UV-B) radiation at ground level, related to stratospheric ozone depletion, are expected to augment adverse health effects such as skin cancer, eye cataracts and suppression of immune response.

While life expectancy has generally been increasing for decades, there has been a sharp reversal in recent years in some countries of Central and Eastern Europe and sub-Saharan Africa. In Russia, life expectancy among men decreased from 65 years in 1987 to 57 in 1994. Causes may include the stresses of economic transition, deteriorating health care, and possibly the toxic burden of decades of environmental contamination. In Africa, the AIDS epidemic is expected to reduce average life expectancy by almost 8 years (WRI/UNEP/UNDP/WB, 1996).


Day, Michael. 1996. "Scourge of infections kills Third World's young", New Scientist, 25 May 1996, p.6.

IPCC. 1995. Climate Change 1995. WMO/UNEP Intergovernmental Panel on Climate Change, Second Assessment Report. Cambridge University Press, Cambridge.

Kochi, Arata. 1996. Kochi, Arata, director of WHO global TB programme, quoted in Spinney, Laura. "Global emergency as TB toll mounts". New Scientist, 30 March 1996, p. 8.

Martin, Philippe H., and Myriam G. Lefebvre. 1995. "Malaria and climate - sensitivity of malaria potential transmission to climate." Ambio 24(4):200-207. June 1995.

Maurice, John. 1993. "Fever in the urban jungle". New Scientist, 16 October 1993, p. 25-29.

Maurice, John. 1994. "The rise and rise of food poisoning". New Scientist, 17 December 1994, p. 28-33.

Pearce, Fred. 1995a. "Global alert over malaria". New Scientist, 13 May 1995, p. 4-5.

WHO. 1996a. World Health Report 1996. WHO, Geneva.

WHO. 1996b. Climate Change and Health. WHO, Geneva.

World Resources Institute/United Nations Environment Programme/United Nations Development Programme/World Bank. 1996. World Resources 1996-97. Oxford University Press, New York and Oxford.


Emerging Issues


UNEP/DEWA/Earthwatch 1996-2003