Yellow fever was another of the cruel impact that the invasion of Europeans and Africans came in the indigenous population. This tragic enemy, like malaria, was accompanied by the mosquito transmitter that made ​​the trip go in water supplies brought by the Spanish ships on their long intercontinental trip.
Yellow fever and black vomit (also called the American Plague) is an acute, infectious viral disease caused by "the yellow fever virus, which belongs to the family Flaviviridae, genus Flavivirus and Yellow. Is an important cause of hemorrhagic illness in many countries in Africa and South America, despite the existence of an effective vaccine. The yellow of the disease is referred to the signs of jaundice that affects some patients.
It was transmited by the Aedes aegypti.


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Smallpox is an infectious disease unique to humans, caused by either of two virus variants,Variola major and Variola minor .The disease is also known by the Latin names Variola or Variola vera . Smallpox localizes in small bood vessels of the skin and in the mouth and throat. In the skin, this results in a characteristic maculupapular rash, and later, raised fluid-filled blisters. V. majorproduces a more serious disease and has an overall mortality rate of 30–35%. V. minor causes a milder form of disease which kills about 1% of its victims. Long-term complications of V. major infection include characteristic scars, commonly on the face, which occur in 65–85% of survivors. Blindness resulting from corneal uceration and scarring, and limb deformities due to arthritis and osteomyelitis are less common complications, seen in about 2–5% of cases. Smallpox is believed to have emerged in human populations about 10,000 BC..



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Thyphus is any of several similar diseases caused by Rickettsiae.The name comes from the Greek typhos (τῦφος) meaning smoky or hazy, describing the state of mind of those affected with typhus. The causative organism Rickettsia is an obligte parasite and cannot survive for long outside living cells. Typhus should not be confused with thyphoid fever, as the diseases are unrelated.

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Typhus was also common in prisons (and in crowded conditions where lice spread easily), where it was known as gaol fever or jail fever, and often occurs when prisoners are frequently huddled together in dark .

Influenza, commonly known as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae (the influenza viruses), that affects birds and mammals.The most common symptoms of the disease are chills, fever, sore throat, muscle pains, severe headache, coughing, weakness/fatigue and general discomfort.Although we use to confuse it with other illnesses, especially the common cold, influenza is a more severe disease than the common cold and is caused by a different type of virus. Influenza may produce nausea and vomiting, particularly in children,but these symptoms are more common in the unrelated gastroenteritis, which is sometimes called inaccurately "stomach flu."
In occasional cases, even for healthy young adults, flu can cause either respiratory distress syndrome or pneumonia, which are manifest with a difficulty in breathing.

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Typically, influenza is transmitted through the air by coughs or sneezes, creating aerosols containing the virus. Influenza can also be transmitted by direct contact with bird droppings or nasal secretions or through contact with contaminated surfaces.
Influenza spreads around the world in seasonal epidemics, resulting in the deaths of a lot of people every year,up to millions in some pandemic years.