A pandemic is the general name of an epidemic disease that affects large continents or the whole world. Except for the covid-19 pandemic which has been affecting the world for the last few years, the history of the world contains lots of different pandemics that killed many people and changed many people’s habits. During these times, deaths have changed lots of things in the world like population and economy.
The most deadly disease that world experienced is the Black Death. This disease was killed 75 to 200 million people and decreased the population as 30% to 60%. The reason why the disease is called the black plague is because the victims’ skins had black-colored wounds because of internal bleeding. The origin of the black death is still controversial ,however, according to the researches, it originates from Middle East or East Asia. It is a bacterial disease and the main character of it is the Yersinia Pestis which is a bacteria. Even though it’s mostly seen as bubonic plague, pneumonic plague and septicemic one might be seen, too. When the plague first appeared, the first reaction was that god was punishing people and the god was showing his wrath to extraordinary things. For example, comets was one of them. Seeing the comets was bonded with the existance of the diseases. Another guilty of the existance of this disease was the people who believe different gods. Especially Jewish people were blamed and claimed for poisining the water wells which are really important for the city life. Unfortunately, this situation caused the execution of many Jewish people without any investigation. However, the main reason of the appearence of this disease was the drought, rodents, fleas and ticks leave the grazing areas and begin to flee to places where are more crowded. We can divide the plague into three as bubonic plague, pneumonic plague and septicemic plague. In bubonic plague the victim suddenly has fever, chills, headache, weakness and one or more painful bubbling appears in the lymph nodes, which can grow to the size of an apple. The disease gets its name from this distinctive symptom, and these bubs are later become black-purple due to internal bleeding. Left untreated, 80% of victims died within eight days. Pneumonic plague has the same symptoms as bubonic plague. To be aware, pneumonic plague is the most dangerous and only airborne droplet type of plague, with a mortality rate of 90 to 95%. Finally, sepistemic plague has the same symptoms as bubonic plague. It can develop from untreated bubonic plague. This disease is spread by rodents and fleas. The Black Death affected society in many ways such as demographic, economic and social.
Another pandemic that effected the whole world was the cholera epidemic. It is a small bowel disease with symptoms such as diarrhea, vomiting and muscle cramps. Cholera is mostly composed of human feces containing the bacteria. It spreads by mixing with water and food. Poorly cooked seafood is an important cause of contamination and it is also the sole host of the human cholera bacterium. Actually the treatment of this disease is really simple. The treatment which is called ‘Oral Rehidration’ is used to make them healthy again. An also, to avoid from cholera, there is a vaccine, too. However, it can’t be said that these vaccines develops a strong immunity.
Another pandemic was the Spanish flu. It was a pandemic that a virus from H1N1 group was caused. Over 500 million people was infected in 18 months and approximately 50 million of them was dead because of this virus. It means it was one of the most deadly pandemics in the history of world. Another feature of Spanish flu was it was not effecting the weak, old or young people more. It was mostly effecting the healthy adults. It was continuing with bleeding nose and fever, and ending with coma or death.
To have a look at Hong Kong flu, it killed more than 1 million people all over the world. Since it was seen at Hong Kong first time, it was named like that. The virus at this disease was also containing the genes of the H2N2 which are also might be found at the bird flu. The effects of the disease were appearing in 4-5 days and the rate of deaths because of this virus was higher at the people who are older than 65 years.
Swine flu is caused by a virus of the family Orthomyxoviridae. It is called swine flu because it is very similar to a virus that occurs in swine. Symptoms of the disease are fever, cough, sore throat, body aches, headaches, feeling cold and tired. A large number of patients reported diarrhea and vomiting. The most important mode of transmission is direct contact with infected or non-diseased pigs. Antiviral drugs are used to treat the disease.
The covid-19 pandemic, which we see actively today, emerged in 2019 in Wuhan, the capital of China. The time required for the symptoms of the disease to appear is 2-27 days. There is evidence that the virus can be contagious without showing symptoms. It has symptoms such as high fever, cough, difficulty in breathing, loss of smell and taste. Covid-19 is transmitted from person to person through the inhalation of virus droplets in the air or on surfaces. If treatment does not respond severe pneumonia, septic shock, acute respiratory distress syndrome (ARDS), multiple organ failure and death may occur. Life in many parts of the world due to the epidemic has come to a standstill. Since the rate of spread is so high, drastic measures need to be taken. Schools were closed, transportation was stopped, and events were banned. This epidemic, which is still ongoing, has had very serious consequences and many people have died in a short time. Covid-19 has killed nearly 70 million people worldwide.
