By Alice Huang 
Infectious diseases, which are also referred to as communicable or contagious diseases are caused by germs or pathogenic microorganisms such as fungi, viruses, bacteria and parasites among others. From their name, these diseases are highly infectious or contagious, which means that their means mode of transmission is from one individual to another either directly or indirectly. The transmission of these diseases occur in a number of ways such as through physical contact, body fluids, contaminated food, transmission by vector organisms and airborne inhalation among others. Research indicates that infectious diseases are very dangerous and that they are responsible for more deaths than any other single cause (Britannica Educational Publishing, 2011).
The history or background of infectious diseases can be traced back to many centuries ago and it is believed that most of them such as malaria, may have originated from the tropical forests of Africa. This is also one of the reasons why these diseases such as malaria and tuberculosis are referred to as tropical diseases. Over the years, a lot of research has been dedicated into the cures and sustainable solutions for eradicating communicable diseases, most of which have borne fruits through major developments (Britannica Educational Publishing, 2011). The research has helped in coming up with ways to control, treat, eradicate and prevent the diseases. Without doubt, these researches have helped in solving millions of people across the globe.
For instance, small pox, which is regarded as one of the most dangerous infectious diseases, was completely eradicated in 1979, after the discovery of the small pox vaccine. Infectious diseases are often classified in accordance to their causes. For instance, as indicated earlier, the major causes of infectious diseases include bacteria, viruses, fungi, protozoa and parasites among others. Some of the major infectious diseases in the world include tuberculosis, malaria, various types of flu such as swine flu and avian flu, small pox, chicken pox, typhoid meningitis, tetanus, Hepatitis B, Syphilis and Measles among others. 
Majority of these infectious diseases are life threatening and they therefore have a major impact on the lifestyles of people. For instance, it some of them are very expensive to treat once contracted especially in terms of finances and time needed for patient management. They also affect the daily lives of people such that whenever there is an outbreak, people have to stay very alert to avoid infections especially for those transmitted through the air (Britannica Educational Publishing, 2011).
 Majority of these infectious diseases are preventable through vaccines and medication after consultation with medical professionals. However, one of the basic and most effective ways of preventing the spread of communicable diseases is by observing hygiene in all aspects of our daily lives. Community awareness is also another way to prevent communicable diseases, in this way the government and some NGO’s are actively involved in educating the communities on ways and measures to curb spread and diseases. In most cases vaccines and medication for such diseases is offered for free. In addition, other cures and solutions for prevention of infectious diseases include immunization, especially for newly-borns which should be kept up to date, eat healthy and hygienically foods, use antibiotics as per the prescription of the doctors, seeking medical attention if infection persists even after medication, being cautious around al, wild animals as well as unfamiliar domestic animals, avoiding unprotected sex, staying alert especially when visiting undeveloped and high risk disease areas as well as areas of insect infestation. 
Some of the major infectious diseases in the world including tuberculosis, malaria, various types of flu such as swine flu and avian flu, small pox, chicken pox, typhoid meningitis, tetanus, Hepatitis B, Syphilis and Measles among others attract major scrutiny from the governments and organizations.
About the Author: Alice Huang is  a sophomore at UC Berkeley, with a major in Molecular and Cellular Biology. She loves to write and writing has become her way of expression for the occurrences in her daily life! She is interested in public health primarily because she likes learning about nutrition and thinks that maintaining a healthy body is more important than trying to find cures to the variety of diseases out there in the world.