Adverse psychological health effects as a result Of flooding in Brisbane during 1 974 included, fifty flood linked suicides and an increase in the diagnosis of post-traumatic stress disorder. (Last, 2006, Michael et al, 2003, & Ditz, 2006) II Onion Southern Oscillation (EONS) is a phenomena occurring every three to seven years caused by warm equatorial water shifting from the Western to Eastern Pacific Ocean. II Onion is the most powerful agent for short term climate variability in the world.
The 1997-98 El Onion event is considered responsible for creating extreme dry conditions leading to forest fires in some parts of the world, along with extensive flooding in others. Climactic change brought about by II Onion has been linked to drought and the spread of diseases such as malaria in Latin America and South East Asia and to a lesser extent, cholera, humanitarian infection and Rift Valley fever. Torrential rain in much of East Africa associated with the 1997-98 II Onion event, caused a malaria epidemic in the highlands of south western Uganda.
During the same period, hospital admissions for children suffering diarrhea in Lima Peru, was two fold higher than that of the preceding four years. The increase in temperature in excess of normal seasonal variations was found to be the main environmental variable impacting upon admissions. The degree to which the frequency and severity of El Onion events are affected by global arming is currently being debated, with many climatologists suggesting a link with global warming. (Pat & Kigali, 2002, Pat, 2004) Weather plays a key role in the dispersal of air-born pollutants.
Periods of high levels of air pollution, ‘air pollution events’ are often associated with slow moving high pressure or anti-cyclonic systems. These systems hamper the normal pollutant dispersal process, leading to higher concentrations of air born pollutants at ground level. Fine particulate pollution is a known hazard to human health and any increase in particulate pollution will see a responding increase in morbidity and mortality. Ground level ozone is the primary ingredient in smog and has been increasing in most urban areas.
Health affects attributable to humans breathing ozone include, asthma, chronic obstructive pulmonary disease, allergic rhinitis and other respiratory conditions requiring hospitalizing. Toxic gases and particulate pollution from forest fires and wild fires etc, poses a similar risk to human respiratory and cardiovascular systems. (Confectioner et al, 2007) Infectious diseases can be classified into two broad groups according to ode of transmission, directly from human to human and via vectors such as mosquitoes and ticks (biological) or non-biological such as soil and water.
Infectious diseases can also be classified as anthropoids (human reservoirs) and zones (animal reservoirs). Infective agents and vectors are limited in geographically by their lack of thermostatic mechanisms. The particular climatic conditions needed for survival and reproduction is known as the ‘climactic envelope’. Global warming may create conditions changing and expanding the climatic envelope, creating scenarios for a greater spread f particular diseases and potentially higher reproductive rates. Michael et al, 2003) Vector-borne and water-borne diseases (WHO, 2003) Mosquitoes are a vector for diseases such as malaria, dengue fever and yellow fever. Mosquitoes require surface water to breed and generally warmer conditions to survive. Therefore any increase in the amount of surface water and ambient temperatures could lead to disease carrying species of mosquitoes spreading disease to previously unaffected areas. An example of this is the outbreak of malaria in recently flooded arid regions of Kenya and Somalia, as a result of the 1997-98 El Onion event.
The concern is that climate change will allow for diseases like malaria to move into areas where the human populations have no protective immunity, leading to the possibility of epidemics. (Eighteen & Woodward, 2003 & WHO, 2003) Changes in surface water quantity, temperature and quality can have a direct impact on the spread of diarrhea diseases such as amoebas, guardians and circumscription, along with cholera and typhoid. Heavy rainfall events can carry microbial agents into drinking water supplies causing contamination.
Conversely a drought induced reduction in surface water laity can lead to higher concentrations of bacteria such as typhoid. This is of particular risk to developing countries, many of whom already have inadequate potable water supplies. Recent studies have identified coped zooplankton as being a water born reservoir for cholera facilitating its spread via the marine food web. A rise in sea temperature may lead to the spread of bio-toxins such as citrate into waters previously free of contamination, making the consumption offish and shellfish potentially hazardous. Eighteen & Woodward, 2003 & WHO, 2003) Flooding caused by heavy rainfall events can lead to increased contact teen humans and rodents facilitating the spread of diseases for which rodents act as vectors. Possible examples of this are lepidopterist outbreaks in Central and South America and South East Asia, along with humanitarian pulmonary syndrome outbreaks (caused by inhaling particles of rodent excreta) in Panama. Rodent numbers are known to increase in temperate zones after higher then normal rainfall.
This may be attributable to increased levels of food source. Drought induced bush fires may have contributed to the spread of Nippy virus and a subsequent epidemic in Malaysia and surrounding countries. Bats acting as vectors for the virus are thought to have migrated from their destroyed habitats to farms, there interacting with humans. (Michael et al, 2003 & Confectioner et al, 2007) Damage to food production through climate change places a huge burden for people living in the developing world, many of whom are already experiencing malnutrition.
The extent to which people are affected will depend upon their geographical location, its sensitivity to climate change and the ability or willingness of governments and non-government agencies to render assistance. Examples of this would be people living in low-lying and load prone or environmentally degraded areas. The effects of global warming may lead to increased migration of effected peoples, making them effectively climate refugees.
This will create further health concerns as potentially large groups of people compete for limited food, water and shelter, creating a scenario for the spread of communicable disease along with diminished health status through malnutrition. (Confectioner et al, 2007) The health implications for climate change are significant for all people no matter where they live. The implications for impoverished or developing Mounties, particularly those in regions likely to be most effected by climactic change, are profound.