Table of ContentsView AllTable of ContentsHow They EnterBacteriaVirusesFungiParasitesProtecting YourselfFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
How They Enter
Bacteria
Viruses
Fungi
Parasites
Protecting Yourself
Frequently Asked Questions
Pathogens are what most people call germs—tiny organisms that cause diseases. There are different types of pathogens found all over the world. Depending on the type of germ and your body, you can get a minor illness or a deadly disease when a pathogen enters.
This article explains four of the most common types of pathogens. It also offers suggestions on how you can protect yourself from diseases they cause.
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How Pathogens Infect the Body
Germs are divided into categories. The most common types are:
These pathogens are different in many ways, but they have one main similarity: Once they’re inside you, they can damage cells or interfere with the body’s normal activities.
Pathogens can enter your body (which scientists call “the host”) in several ways:
Not all viruses, bacteria, fungi, and parasites are pathogens. Instead of causing disease, some help the body. For instance, “good bacteria” in yogurt and other fermented foods may lower your risk of type 2 diabetes and heart disease.
All the Ways Germs Can Be Transmitted
Most bacteria are actually harmless. However, some can causebacterial infections. Often, these germs make toxic chemicals. As the bacteria quickly multiply, their toxins kill or damage healthy tissue.
Examples of bacterial infections include:
If a certain infection is confirmed and likely to progress and/or cause harm quickly, your healthcare provider will prescribe antibiotics right away.In other cases, they may take a “wait and see” approach, giving the infection a chance to clear up on its own without medication in an effort to avoid antibiotic resistance.
Antibiotic resistance happens when someone uses antibiotics too often. The medications can no longer effectively fight the bacteria because the pathogens have essentially outsmarted them.
One example ismethicillin-resistantStaphylococcus aureus(MRSA), a staph infection that has become immune to antibiotics normally used to treat other infections in the staph family.
How Your Doctor Chooses the Right Antibiotic
Virusesneed to live on and feed on something. Unfortunately, what they live and feed on isyou. Smaller than most bacteria, these germs spread easily from person to person.
Examples of viral infections range from mild to severe and include:
Treatments for viruses depend on the infection type. In general, treatments won’t kill the virus in your body. Medication, rest, andbuilding your immunity, though, can help you deal with symptoms while you wait for the virus to run its course or for a flare-up to end.
There are three main goals of virus treatment:
Some viral infections, like influenza or HIV, can increase your risk of developing a bacterial infection.
Fungi live in the air and soil, on plants, and in water. Different types of fungi are harmful to people.When fungi in nature reproduce, they send spores into the air. If you inhale the spores or get them on you, they can get into your lungs or on your skin where they can grow and cause problems likefungal pneumoniaor afungal rash.
There are three types of fungal infections:
Having an organ transplant or HIV weakens your immune system and makes you more likely to get any type of fungal infection.Taking antibiotics also puts you at risk.
If you have a life-threatening fungal infection, your doctor may prescribe a very strong antifungal medication (fungicide). These drugs, such asamphotericin, have serious side effects but may be necessary for major infections.
Parasites are organisms that live on or in you at your expense. They may be simple, one-celled organisms or multicellular organisms. They cause illness while feeding on your cells. Some parasites that cause illness include:
Doctors treat parasites with anti-parasitic drugs. The type of parasite determines which types of medications can be used. Your doctor also needs to consider your overall health, age, weight, and other factors.
In some areas of the world, different parasites are resistant to one type of treatment. This is an issue formalaria treatmentin several places, for instance.Alternative medications then need to be considered.
What Is a Parasite Cleanse and Does It Work?
Defending Against Pathogens
Your body is equipped with amazing ways to defend itself against pathogens. Nose hair, for instance, acts as a filter that stops some germs from getting into the body.
A healthy immune system, though, is the best defense you have against germs. Focus on everyday healthy habits—eat well, exercise, and get enough sleep—to support its efforts.
Also commit to these effective strategies for staying well:
Staying Healthy When Your Family Is Sick
Summary
Bacteria, viruses, fungi, and parasites are all types of pathogens that can cause minor or severe health issues when they enter your body. Each of these pathogens includes a variety of subtypes that are responsible for a wide range of infections or diseases.
To avoid complications related to these illnesses, do your best to prevent infections in the first place. Building a healthy immune system and knowing how to avoid situations that put you at risk for pathogen exposure are the most effective ways to stay healthy.
Viruses differ from other pathogens in that they have only one purpose—to get inside a host and replicate itself. That host can be a human or any living thing, including bacteria and fungi. Viruses are extremely simple pathogens that are even smaller than bacteria.
No, not all bacteria are pathogenic. In fact, most are considered helpful and essential to human life. For example, the bacteria that reside in our intestines, known as gut flora, help us digest food. Other types of bacteria help us fight disease, such as pathogenic bacteria.
There are about 1400 human pathogens that have been identified, but there are believed to be many more which have not yet been discovered. This total amount is made up of the four main categories of pathogen (bacteria, viruses, fungi, and parasites).
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