Top 10 Most Contagious Illness.

While nobody likes to get sick, count your blessings when all you have are the sniffles or a low-grade fever from the flu. Nobody thinks about some of the most devastating illnesses that have literally altered history due to the safety net of modern medicine, but there are many cases of diseases still today causing mass destruction, devastating large regions in extremely short periods of time.


10. Smallpox

Officially eradicated from human populations since 1979, there are still countries that require vaccination against the disease. This disease spread notoriously fast among humans and caused an unknown number of epidemics in history. Most common side effects of the disease was maculopapular rashes and skin blisters, however, due to its inhabitants in the blood vessels of the skin, mouth, and throat, it was also known to cause blindness and usually ended in death.


9. Leprosy
Caused by Mycobacterium Leprae, leprosy or Hansen’s disease affects the peripheral nerves of the body, rendering them useless. While in itself not fatal, the lack of feeling from the disease meant injury and overexposure in extreme temperatures lead to infection and death. Originally believed to lead to the loss of limbs, for several millennia leprosy caused fear resulting in those affected being outcast from society.


8. Typhoid Fever
While this disease has only a 20% fatality rate, it is one of the most contagious due to its deceptive nature. The disease’s symptoms can remain dormant for large amounts of time after infection, meaning without treatment an individual can infect untold populations without ever knowing it. Transmission occurs due to intake of contaminated food and water with human waste makes it particularly common in areas with poor sanitation.

7. Bubonic Plague
Also known as the “Black Death,” the bubonic plague is not spread by humans, but rather by fleas on rodents (namely rats). The most feared disease in the middle-ages, the plague was responsible for decimating half the European population in the 14th Century. The disease infects the lymphatic system and attacks the immune system directly, causing death in as little as four days after symptoms emerge.


6. Influenza

The flu is a historically notorious human killer. Most of its forms are highly contagious, and it attacks the respiratory system causing symptoms that can include fever, fatigue, coughing, congested sinuses, nausea, vomiting, diarrhea, and aching muscles. Even today, an estimated 36,000 people die from the flu in the U.S. every year.


5. Rabies
While uncommon in humans today, rabies is still a terrifying disease. With symptoms including foaming at the mouth, new fear of water, hostile delusions and violent hallucinations, the disease directly attacks the central nervous system and the brain. Spread through saliva, this strange and terrifying disease’s vaccination was developed in 1885. However, rabies still kills approximately 50,000 people a year.


4. Malaria
This particularly vicious disease attacks without warning or restraint upon infection. Spread by mosquitos, Malaria is recognized by a severe fever and headaches leading to coma and sometimes death. This disease is most common in tropical and subtropical climates and is caused by a Plasmodium parasite.


3. Giardiasis
This disease, also known as “beaver fever,” is one of the most common waterborne diseases in the U.S. Believed to be caused by beavers and other aquatic mammals that infect lakes, rivers, and reservoirs, infected water is then consumed by humans.

2. Ringworm
This highly contagious fungal infection of the skin known as Dermatophytosis, or ringworm, is mistakenly believed to be caused by a breed of parasitic worm. In fact, the disease is caused by several species of fungi and is spread through skin to skin contact.


1. H.I.V.
The Human immunodeficiency virus, or HIV, is one of the most feared epidemics in today’s society. The condition leads to AIDS and leads to the deterioration of the immune system. This means sufferers are extremely vulnerable to infections of any shape or size. The virus is transmitted through direct contact of a mucous membrane of the bloodstream with a bodily host fluid, most commonly transmitted through unprotected sex and use of contaminated paraphernalia amongst drug addicts.

Despite modern medicine, getting a disease is still inevitable. It is terrifying to think diseases like these still exist and are developing