Pandemic means an infectious disease that spreads to the whole world and Epidemic means a contagious disease that is regional or area confined. (In Greek, Pan = all, demos = people). There are many pandemics diseases that have affected the life of man during the twentieth century. Some of them are noted below.
Also known as Asiatic or Epidemic Cholera, it is a food or water borne disease caused by the bacterium called Vibrio cholerae causing gastroenteritis and related problems. From 1899 1923 Russia was badly affected and as many as half a million people died from cholera during the second half of that phase. The cholera bacteria are transferred from person to person through contaminated food and water, especially large bodies of water and drinking sources contaminated with the bacteria.
Many kinds of Influenza (the flu) which have been around are contagious respiratory illnesses caused by the influenza viruses. Symptoms vary from mild to severe and at times can lead to death. Prevention of the flu is by regular annual shots of the Influenza vaccine.
The “Spanish flu”, 1918 1919. This was first identified at the Kansas Training Camp at Camp Funston in 1918. It spread to nearly every part of the world and was considered a global disaster. The Spanish flu was also called the La Grippe and it affected mainly the age group of 20 40 years of age.
The “Asian Flu”, 1957 58. An H2N2 virus caused about 70,000 deaths in the United States. It was first identified in China in late February 1957, the Asian flu spread to the United States by June 1957. It caused about 2 million deaths globally and affected the elderly.
The “Hong Kong Flu”, 1968 69. An Influenza virus subtype H3N2 was first detected in Hong Kong in early 1968. Is believed to have arisen in pigs and contain the avian flu gene too.
AIDS / HIV:
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome (AIDS) is a disease of the human immune system caused by the human immuno-deficiency virus (HIV). HIV went directly from Africa to Haiti, and then spread to the United States and much of the rest of the world beginning around 1969. HIV targets the immune system and affects the overall defence system of the body making a person highly susceptible to every illness around, even a common cold, which can lead to death. HIV is transmitted through direct contact body fluids containing HIV, such as blood, semen, pre-seminal fluid, vaginal fluid, and breast milk. This has been a deadly feared pandemic for many years, but today, modern medicine has a lot to offer patients, making them enjoy up to an additional ten years which they would otherwise have lost compared to earlier outbreaks of this disease.
Smallpox is a highly contagious disease caused by the Variola virus, Variola major and Variola minor . During the 20th century, it is estimated that smallpox was responsible for 300500 million deaths. Smallpox is an infectious disease unique to humans. It localizes in small blood vessels of the skin and in the mouth and throat. In the skin, this results in a characteristic maculopapular rash, and later, raised fluid-filled blisters.
Tuberculosis is a disease seen even today. About a third of the world’s population suffers from this and it caused by the virus Mycobacterium tuberculosis. It attacks the lungs in humans and is seen as pulmonary TB but can also affect other parts of the body such as the bones, joints, gastro-intestinal system and central nervous system. About 100 million people died from TB during the twentieth century. Tuberculosis is one of the most deadly diseases that the developing countries battle with continuously as it is a slow killer and affects not just the patient but families as a whole by its psychological and economic consequences.
There are many more pandemic diseases apart from the ones mentioned here, such as Malaria, Leprosy, Yellow Fever, Typhus, etc. Education, a united effort to support countries in time of need, and timely response to dealing with outbreaks of pandemics are ways to deal with these issues. On the other hand, there are some diseases that are not considered epidemics although they fall under the category of allergy epidemics; hay fever, eczema and asthma. It is said that the UK is battling with a major asthma problem, while people who are exposed to open fields suffer from hay fever during the spring. Asthma is also noted higher in areas where people stay by the road side and are exposed to fuel toxins from vehicles.