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20 Deadiest Diseases In The World

1. Cholera

Cholera is the infection of the small intestine and is transmitted primarily by drinking water or eating food containing the feces of an infected person. 5 millions people are affected and over 100,000 die from Cholera every year.

2. Smallpox

If we look back in time at the history of diseases, Smallpox was one that was quite rampant at one point. SmallPox is a serious illness caused by a virus called the Variola. Basically they are puss filled blisters that cover the body. Luckily, after the 20th century vaccine campaigns, Smallpox has become eradicated. Throughout its time though, smallpox claimed numerous lives and just in the 20th century, prior to vaccination, the death toll was estimated at nearly 500 million.

3. Yellow Fever

A tropical viral disease that affects the liver and kidneys, causing fever and jaundice and it’s often fatal. YellowFever is transmitted by the bite of female mosquitos. This disease is found in Africa and South America. Typical involves fever, chills, anorexia, nausea, muscle pain and headache. Approximately 200,000 cases of yellow fever occur worldwide and account for 30,000 deaths.

4. Tuberculosis

Also known as TB is a lung condition cause by bacteria called Mycobacterium tuberculosis. It’s an airborne disease that is often successfully treated. In 2012, about 900,000 people lost their lives to TB. Many deaths take place in poorer countries, and it is one of the top causes of death for people who have HIV.

5. Influenza

Commonly known as the flu, you may have heard of it. It is usually transmitted through air like tuberculosis but sometimes through direct contact with contaminated surfaces. The sweats, chills, aches and pains, vomiting, diarrhea, the intense need to spend the day in bed. All symptoms of the flu! Most of the time, rest and hydration can solve the sickness, but there are some cases, predominantly in older people and babies, where it can lead to death.

6. Lung Cancer

Cancer, we all know it, it’s probably effected someone you know. Not a sickness anyone wants to get… Cancer can occur anywhere in the body, and studies have shown that some areas are worse than others. But on a world wide scale, lung cancer is the most common cancer related death in men and women, responsible for 1.38 million deaths annually.

7. Whooping Cough
In technical terms, known as Pertussis, this is a highly infectious bacterial disease, known in some countries as the “cough of 100 days”. It mostly effects children and it results in convulsive coughs, followed by a whoop.

8. Ebola

Ebola, you may have most recently heard this disease in the news. Ebola originally derives from the Ebola river in the Republic of the Congo. It is an infectious and generally fatal disease. Spread through contact with infected body fluids. Victims of this disease usually suffer from fever, muscle weakness, and other symptoms that progress to sever bleeding, both internal and external, that eventually causes them to bleed to death. Unfortunately no legitimate treatment is yet discovered.

9. Avian Influenza (Bird Flu)

Yes, we have already looked at the flu, but viruses spread, and can adapt to particular species. In this case, it is birds! The way most humans could contract this flu is through handling dead or infected birds or from contact with infected fluids. For this reason, many large outbreaks have occurred in agricultural parts of Asia and Africa. Symptoms are influenza like, fever, cough, sore throat and muscle aches and could lead to hospitalization.

10. Tetanus

A medical condition, bacterial disease that is characterized by a prolonged contraction of skeletal muscle fibers. Basically marked by rigidity and spasms of the muscles. It is contracted through wound contamination and can involve a cut or a deep puncture would.

11. Coronary Artery Disease

Experts suggest that this is THE deadliest disease in the world. The WHO estimates that approx: 7.4 million people die of heart disease each year. Unfortunately a majority of those deaths occur in low and middle income countries. Eating habits, smoking and general lifestyle decisions will effect your chances at getting this disease.

12. Meningitis

Is an inflammation of the protective membranes covering the brain and spinal cord. The inflammation may be caused by infection and possibly by certain drugs. If you develop meningitis, you may suffer from intense headaches, fever, sensitivity to light, muscular rigidity and in severe cases, convulsions, delirium and death.

13. SARS

This is a viral respiratory disease in humans, if you’re from Toronto, you may remember this outbreak years ago. In basic terms, it’s a more serious form of pneumonia.It can cause a lot of respiratory distress. Luckily, the last recorded outbreak occurred in 2003. And has not yet surfaced again.

14. Syphilis

A sexually transmitted disease… Not one you want to acquire in the bedroom. This disease is believed to infect roughly 12 million people annually, with 90% of the cases in the developing world. Symptoms include rashes, and can lead to heart problems.

15. Lower Respiratory Infections
The WHO estimates that lower respiratory infections caused about 3.1 million, or 5.5 percent of deaths in 2012. This group of diseases includes pneumonia, bronchitis, and influenza. The majority of these infections occur during flu season, which is December thru February in the Northern Hemisphere and from June thru August in the Southern Hemisphere and all year round in tropical regions.

16. Stroke

A stroke is when an artery in the brain is blocked or leaks. Oxygen-deprived brain cells begin to die within minutes. Strokes occur to approx: 15 million people world wide every year! Nearly 6 million of those die and 5 million are left permanently disabled.


HIV is short for Human Immunodeficiency virus. It’s a virus that attacks the immune system. HIV can cause AIDS: Acquired immunodeficiency Syndrome. AIDS is a chronic, life threatening condition. According to the Foundation for AIDS Research, since the start of the pandemic, almost 39 million people have died due to HIV/AIDS. In 2013 alone, 1.5 million people lost their lives to Aids. That’s about 2.7 percent of deaths worldwide. 5,700 people become infected with the HIV virus everyday. HIV is spread through bodily fluids. Including: Blood, Semen, Pre Seminal Fluid, Rectal Fluids, Vaginal Fluids, Breast Milk.

18. Diarrheal Diseases

Have you ever been affected by this? Diarrhea is when you pass three of more loose stools a day. When diarrhea lasts more than a few days, your body looses too much water and salt. Death may be a result when dehydration occurs. Diarrhea can be caused by an intestinal infection transmitted through viruses, bacteria or even parasites. These infections can be spread through contaminated water or food. It is quite wide spread in nations with poor sanitary conditions.

19. Diabetes Mellitus

Diabetes is a group of diseases that affects insulin production and use. With type 1. Diabetes, the pancreas can no longer produce insulin. The cause is not known. Type 2 diabetes, the pancreas doesn’t produce enough insulin, or it cant be used effectively. Type 2 can diabetes can be caused by a number of factors, including poor diet, lack of exercise and carrying too much weight.

20. Malaria

Caused by a parasite that infects mosquitoes. People can contract Malaria by being bitten by an infected mosquito. According to the WHO, 637,000 deaths were caused by Malaria in 2012. Many of these deaths are in Sub-Sahara Africa. Malaria is not transmitted from person to person, but by infected mosquitoes. Those who are able to find medication where they live or while travelling, will not contract this disease.