The Top 5 Most Deadly Diseases

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Some diseases terrorize people by their rapid spread or disgusting symptoms. Others slowly march along, quietly infecting and slaying millions, though they might not sound so frightening at first. The World Health Organization documented these top 5 killers from 2008 data.

5 Diarrheal Diseases

Diarrheal diseases are the most tragic of the 5. Despite being preventable and treatable, they’re still the second major killer of children under 5, with people in less developed countries who lack access to safe water being most at risk. Infection spreads through viral, bacterial or parasitic organisms that are passed through water or between people. The actual cause of death is usually extreme dehydration due to depletion of water and salts. Chronic diarrhea also leads to malnutrition, especially in children. Diarrheal diseases claim 2.46 million lives per year, or 4.3 percent of total deaths.

4 Chronic Obstructive Pulmonary Disease

This extremely unpleasant disease makes breathing more difficult as it progresses. Symptoms include wheezing, chest tightness, shortness of breath and an overabundance of mucus. In COPD, the little air sacs in your lungs—where the vital exchange of oxygen and carbon dioxide takes place—become increasingly inefficient, due to damage, inflammation or mucus-clogged airways. COPD is usually the result of smoking or other lung irritants, such as dust, chemical fumes or air pollution. The world loses about 3.28 million people to COPD annually, accounting for 5.8 percent of deaths.

3 Lower Respiratory Infections

This group of diseases, including bronchitis and pneumonia, affects the lower respiratory tract. Lower respiratory infections result in about 3.46 million deaths worldwide per year, or 6.1 percent of total fatalities. Sometimes viruses are the culprit, sometimes bacterial growth in your lungs. Lower respiratory infections start out innocently enough; symptoms like sneezing, runny nose and sore throat resemble a common cold.

2 Cerebrovascular Disease

Cerebrovascular disease—commonly known as a stroke—kills 6.15 people each year. This is about 10.8 percent of total deaths. When a blood vessel is blocked, oxygen can’t get to the brain and you have an ischemic stroke. If a blood vessel bursts, that’s a hemorrhagic stroke. Either way, your brain cells die, causing permanent damage or death. High blood pressure is the top predictor for stroke, so get yours under control!

1 Ischemic Heart Disease

Felling 7.25 million people around the world annually, ischemic heart disease accounts for 12.8 percent of all deaths. “Ischemic” means that not enough oxygen and blood are getting to the heart due to blocked arteries. The results? Heart failure and death. If you are obese and have diabetes or high blood pressure, your odds of developing ischemic heart disease increase. This disease is especially prevalent in middle-aged and senior men.
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