User:Rtoteja27/FOUNDATION COURSE/ENVIRONMENT AND PUBLIC HEALTH

UNIT I

LINKAGES BETWEEN ENVIRONMENT AND HEALTH

WHO Articles on Public Health and Environment, PHE

Health Organization, Public Health & Environment Strategy Overview

Capacity Building in Environmental Health Research in India and Nepal

CLIMATE CHANGE AND IMPLICATIONS ON PUBLIC HEALTH

Climate change is a global issue and its adverse impact can affect the entire world. However, the poor and the most vulnerable populations are likely to be disproportionately affected, with poorer nations bearing the brunt of the impact due to deficient health systems and resources. The World Health Organization (WHO) estimates that every year about 150 000 deaths occur worldwide in low-income countries owing primarily to the adverse effects of climate change, primarily crop failure and malnutrition, floods, diarrhoeal diseases and malaria. Changes in climate affect the average weather conditions. Overwhelming evidence shows that climate change presents growing threats to public health security. There is a concern world over about this issue and this has taken a main stage internationally as is evident from:

1. The Nobel Peace Prize 2007 was awarded jointly to Intergovernmental Panel on Climate Change (IPCC) and Albert Arnold (Al) Gore Jr. "for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change"

2. The World Health Day – 2008 theme “Protecting health from climate change” raises the profile of health dangers posed by global climate variability and change. It was selected because overwhelming evidence shows that climate change presents growing threats to international public health security.

Developing country populations, particularly in small island states, arid and high mountain zones, and in densely populated coastal areas are considered to be particularly vulnerable. India is a large developing country, with the Great Himalayas, the world's third largest ice mass in the north, 7500 km long, and densely populated coast line in the south. Nearly 700 million of her over one billion population living in rural areas directly depends on climate-sensitive sectors (agriculture, forests, and fisheries) and natural resources (such as water, biodiversity, mangroves, coastal zones, grasslands) for their subsistence and livelihoods. Heat wave, floods (land and coastal), and draughts occur commonly. Malaria, malnutrition, and diarrhea are major public health problems. Any further increase, as projected in weather-related disasters and related health effects, may cripple the already inadequate public health infrastructure in the country.

Health manifestations of climate change Impacts of climate change on health are manifested directly due to heat, cold or indirectly through changes in environment, agriculture, human behaviour and migrations. Direct effects of extreme events An increase in the frequency and intensity of extremes of temperature, precipitation and wind speed have clear implications for mortality and morbidity. Flooding and storms increase the risk of deaths and non-fatal injuries. Prolonged heat exposure may lead to heat exhaustion or heatstroke.

Acute variation in temperature and precipitation, can lead to various Patho-Physiological (Hypo-Hyper thermia, heart stroke, burns, frost bites etc). Extreme weather events such as severe storms, floods and drought can have obvious results such as physical injuries and drowning. Rising sea-levels will also give rise to flooding leading to drowning and population displacement. Indirect and chronic effects There are many indirect effects as: communicable diseases e.g.: vector borne disease, diarrheal diseases; ecological disturbances impacting on agent- host-environment relationships; malnutrition resulting due to agricultural impacts leading to food security issues; environmental health related to air and water quality issues, and human behavior issues such as migrations, and mental health. Changes in climate may enhance the spread of some diseases. Food-borne Diseases • Higher air temperatures can increase cases of salmonella and other bacteria-related food poisoning because bacteria grow more rapidly in warm environments. These diseases can cause gastrointestinal distress and, in severe cases, death. • Flooding and heavy rainfall can cause overflows from sewage treatment plants into fresh water sources. Overflows could contaminate certain food crops with pathogen-containing feces.

Water-borne Diseases • Heavy rainfall or flooding can increase water-borne parasites such as Cryptosporidium and Giardia that are sometimes found in drinking water. These parasites can cause gastrointestinal distress and in severe cases, death. • Heavy rainfall events cause storm water runoff that may contaminate water bodies used for recreation (such as lakes and beaches) with other bacteria. The most common illness contracted from contamination at beaches is gastroenteritis, an inflammation of the stomach and the intestines that can cause symptoms such as vomiting, headaches, and fever. Other minor illnesses include ear, eye, nose, and throat infections.

Animal-borne Diseases Extreme weather events might then create the necessary conditions for vector borne disease to expand its geographical range. As the ambient temperature of a region rises, the ecology changes and therefore populations of disease carrying animals or insects may increase as well. Mosquitoes Borne Diseases e.g., Malaria, Dengue, Chikungunia, Yellow fever, Filaria are some of most climate sensitive diseases in which there is a direct correlation with temperature and rainfall which can be demonstrated. In some areas, drought may reduce the transmission of some mosquito borne diseases, leading to reduction in the proportion of immune persons and therefore a larger amount of susceptible people once the drought breaks.. The spread of Plague, West Nile and Lyme disease are indicative of impact of pests on public health. Respiratory Disease The quality of air is likely to decrease as surface ozone concentrations begin to rise with increasing temperatures. This will lead to an increasing incidence of asthma and other cardiovascular and respiratory diseases. Under-nutrition Rising temperatures and variable rainfall will ultimately lead to an increase in crop failures and therefore a decline in food security, especially for crop staples such as rice and wheat. Poorest regions will be the most affected and rates of under-nutrition will begin to increase.