Any organism that can produce disease is a pathogen. The term came into use in the 1880s and is now used to describe any infectious agents – a bacterium, virus, viroid, fungus, prion and parasite - are all examples of pathogens. These agents can cause disease in their host that can be a plant, an animal, a fungus or another microorganism. Pathogens use several pathways and substrates to enter the body of their host. Keep reading to find out more.
7 Examples of Pathogens
There are different types of Pathogens. Here you will know 7 pathogens that are most commonly seen in our life.
1. Bacteria
You have good bacteria in your gut, but some bacteria are pathogens and invade your system to cause diseases. They are single-celled living organisms and they need living human cells to survive. They kill human cells and cause several diseases, such as pneumonia, tonsillitis, syphilis and botulism. You need to take antibiotics to treat bacterial infections.
2. Viruses
They are extremely small infection agents with a piece of genetic material, either DNA or RNA covered with a protein coat. They are not composed of cells, or called cellular microorganisms, but release the viral genetic material when they enter the cell of a host. Some viruses merge their outer coat with the cell membrane of their host and release ectoplasm, which can cause diseases such as hepatitis, AIDS, encephalitis, chicken pox, rabies, measles, flu, polio, etc.
3. Prions
They are infectious proteins and are the newest examples of pathogens, which can lead to the buildup of misfolded proteins in your nerve cells and hamper nerve cell functions.
4. Protozoa
These single-celled organisms can contaminate your food and lead to infections such as amoebic dysentery with several symptoms like diarrhea. Some of these pathogens act as parasites and live on another organism.
5. Viroids
These are the smallest infectious pathogens known until now. They have very short strands of circular RNA – they don't have any protein coats though. These genomes can be extremely small and are usually between 246 and 467 nucleobases. They are generally plant pathogens, but some of them are human pathogens, especially the hepatitis D virus that's essentially a defective RNA virus. Instead of coding for protein, viroids use RNA polymerase II for replication.
6. Fungus
Fungus is a human pathogen that can cause several diseases. Even though your immune system uses physiological defense against fungus, some may end up disturbing your body's flora and fauna, leading to an infection. Fungi make up a eukaryotic kingdom of microbes (mainly saprophytes) but they can still cause diseases. These examples of pathogens can cause life-threatening infections on people with compromised immune system. Antibiotics used for bacterial pathogens are usually useless against fungal infections.
7. Human Parasite
Human parasites include a variety of worms and protozoa, which can cause several parasitic diseases in human. These parasites can also be endoparasites, which can cause infections inside your body. They can also be ectoparasites that infect you within the skin. The eggs and cysts of endoparasites are usually found in feces.
Check out the following video to learn more about some examples of pathogens:
How Do Pathogens Spread?
Now that you know a bit about pathogens, it's time to learn different ways in which pathogens spread, so you can take measures to protect yourself.
- Droplet Infection: When you sneeze, cough or talk, you release tiny droplets in the air. These droplets come through your nose and mouth. If you already have an infection, these droplets will contain pathogens that can infect others when they inhale these droplets. Diseases such as tuberculosis, flu and the common cold are the outcome of droplet infection.
- Direct Contact: You may transfer your infection to someone else through direct contact of the skin. Athlete's food is one great example of spreading pathogens through skin contact. Some sexually transmitted infections such as genital herpes are spread in the same way.
- Contaminated Food and Water: Some pathogens can survive in foods and water, such as undercooked food and contaminated drinking water. You can contract these pathogens when you eat such food or drink such water. When they enter your system through water, they cause cholera; when it is through food, then they cause salmonella.
- Through Body Fluids: Pathogen can infect you by entering your body through semen and blood. Some of the most common examples of pathogens that spread through body fluids are hepatitis and HIV viruses.
- Vectors: It's an animal that spreads disease-causing pathogens from one host to another. Common examples of vectors are houseflies that cause dysentery and mosquitoes that cause malaria.
Here's a funny and interesting video to learn how your body fights pathogens: