What causes infectious diseases? A question that many students and researchers in the medical field are looking for, and in this article on my website we will answer this question in a detailed and accurate manner. We will also explain the concept of infectious diseases and their impact on humanity over the years, and we will address the most dangerous infectious diseases that have passed on humanity.

 

What are infectious diseases?

 

Infectious diseases, which are disorders caused by living organisms such as bacteria, viruses, fungi or parasites, where many organisms live in and on our bodies, usually harmless or sometimes beneficial, but under certain conditions, may Some of these organisms cause disease, and some infectious diseases can be transmitted from one person to another, and some are transmitted by insects or other animals.

 

Some may contract it by ingesting contaminated food or water or exposure to organisms in the environment. Signs and symptoms vary depending on the organism causing the infection, but they often include fever and fatigue, and mild infections may respond to rest and home treatments, while some types of threatening infections may need Life leads to hospital admission. Many infectious diseases, such as measles and chickenpox, can be prevented with vaccinations. Frequent and thorough hand washing also helps protect you from most infectious diseases.

 

What causes infectious diseases?

 

What causes infectious diseases? There are many causes that lead to infectious diseases, and these are the most important reasons:

 

Bacteria :  These single-celled organisms are responsible for diseases such as strep throat, urinary tract infections, and tuberculosis.Viruses :  Smaller than bacteria, viruses cause many diseases ranging from the common cold to AIDS.Fungi :  They cause many infectious skin diseases, such as ringworm and athlete’s foot, and other types of fungi can infect your lungs or nervous system.Parasites :  Malaria is caused by a small parasite transmitted through the bite of mosquitoes, and other parasites may be transmitted to humans from animal faeces.

 

The most dangerous infectious  diseases

Unfortunately, there are many ways for infectious diseases to spread, and in the end, this spread can cause epidemics in regions, and here are the most common reasons for the spread of diseases among humans:

• Direct person-to-person contact, as infectious diseases usually spread through direct transmission of bacteria, viruses or other germs from one person to another, and this can happen when a person infected with the bacteria or virus touches another uninfected person or when he kisses him, coughs or sneezes in the face of a person Uninfected.
• These germs can also spread through the exchange of bodily fluids from sexual contact, and the person transmitting the germ may not show symptoms, but may just be a carrier of the disease.
• Transmission from animal to person, as being bitten or scratched by an infected animal, or even a pet, can make you sick, and in extreme circumstances, can be fatal, and handling animal waste can also be dangerous, for example You get toxoplasmosis infection by washing your cat’s litter box.
• Transmission from a mother to an unborn child, as a pregnant woman may transmit germs that cause infectious diseases to her unborn child, and some germs can pass through the placenta or through breast milk, and germs in the vagina can also be transmitted to the child during childbirth.
• Through indirect contact, as disease-causing organisms can also be transmitted through indirect contact, for example, many germs can remain on an inanimate object, such as a tabletop or door handle.

The most dangerous infectious disease

Infectious diseases have shaped human history and are still with us today. Here is a look at some of the worst infectious diseases that have ever passed on humans:

• Corona Virus :  The new Corona virus is a new strain of Corona virus that first appeared in Wuhan, China, at the end of 2019, and has already spread rapidly in China and around the world.
• Smallpox :  Scientists believe that smallpox, which causes skin lesions, appeared about 3,000 years ago in India or Egypt.
• Plague :  This ancient killer is still with us, due to a bacteria carried by fleas, as the plague ravaged societies including the fourteenth century in Europe during the period of the Black Death.
• Malaria :  Although malaria is both preventable and curable, it has devastated parts of Africa, where the disease accounts for 20 percent of all child deaths.
• The Spanish flu is  the most devastating viral infection. In the 1918 pandemic, it killed nearly 50 million people worldwide.
• Tuberculosis :  Tuberculosis is deadly due to the bacteria Mycobacterium tuberculosis, which usually attacks the lungs and causes coughing up blood.
• Cholera : Cholera  causes severe diarrhea that if left untreated can kill within hours, and people may become ill by eating or drinking items containing the bacteria Vibrio cholerae.
• Rabies :  Rabies is still a deadly problem in some regions of the world, and according to the World Health Organization, rabies causes tens of thousands of deaths every year in countries in Africa and Asia.
• Pneumonia : Pneumonia  may not be as dreadful as diseases such as rabies or smallpox, but this lung infection can be fatal, especially for those over 65 or younger than 5.
• Ebola :  Although rare, Ebola virus disease is an often fatal infection, caused by one of the five strains of the Ebola virus. The virus spreads very quickly, overpowering the body’s immune response, and causing fever, muscle aches, and headaches.
• Middle East Respiratory Syndrome :  It is a viral respiratory disease that was first identified in Saudi Arabia in 2012

At the end of the article, we have answered a question, what causes infectious diseases, and we have also mentioned some of the most dangerous infectious diseases that have passed on humanity, and in the end we have to say that every serious disease that afflicted the world, humans were eventually able to overcome and find vaccines that limit the spread of these diseases.