What Is the Chain of Infection?

Infections are to be expected, especially in wounds that are taking too long to heal or wounds that are recovering poorly. We know what an infection looks like, but do we know how it started and why it happened in the first place?

This blog will discuss the chain of infection and what can we do to prevent and treat it if necessary.

What is an infection?

An infection is the invasion and growth of germs in the body. It can cause fever and other health problems. When the body’s immune system is strong, it can often fight the germs and cure an infection.

The main types of germs that can cause infections are:

  • Bacteria
  • Viruses
  • Protozoa (some of which act as parasites)
  • Fungal organisms (also called fungi)

What are the types of infections?

There are four main types of infections:

  • Viral infection - Viruses can cause a wide range of infectious diseases by killing cells or interfering with cell function. Most viral diseases are self-limiting, and the immune system may be able to fight them off. In rare cases, doctors may prescribe antiviral medications. Vaccinations can also help fight viral diseases.
  • Bacterial infection - Bacteria cause many infectious diseases, including strep throat and urinary tract infections, meningitis, and tuberculosis. Bacteria can enter the body through wounds, scrapes, surgical incisions, and the mouth and nose. Antibiotics are the first-line defence against bacterial infections.
  • Fungal infection - Fungal infections are often more bothersome than dangerous, and some can cause serious illness. Infected people are treated with a combination of antibiotics and antifungal medications.
  • Parasitic infection - In healthy people, parasites cause mild illness, but those with weakened immune systems can develop serious infections that can spread to major organs. Protozoa is a type of parasite that frequently spreads disease via water. Oral rehydration therapy is usually the first-line treatment. Antiparasitic drugs can be used to treat severe cases.

What is the chain of infection?

The chain of infection has six links, namely the infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, and susceptible host.

  • An infectious agent is a pathogen (germ) that causes diseases.
  • The reservoir is the place or environment where the pathogen lives (this includes people, animals and insects, medical equipment, and soil and water).
  • Fungal infection - Fungal infections are often more bothersome than dangerous, and some can cause serious illness. Infected people are treated with a combination of antibiotics and antifungal medications.
  • The transmission method is how the infectious agent can be passed on (through direct or indirect contact, ingestion, or inhalation).
  • The Port of entry is how the infectious agent can enter a new host (through broken skin, the respiratory tract, mucous membranes, and catheters and tubes).
  • The susceptible host can be any person (the most vulnerable of whom are receiving healthcare, are immunocompromised, or have invasive medical devices, including lines, devices, and airways).

The way to stop germs from spreading is by interrupting this chain at any link. 

How to break the chain of infection?

All six links need to be connected for an infection to happen, so even if only one link is broken, an infection will not occur.

You can break the chain of infection by:

  • Cleaning your hands frequently
  • Staying up to date on your vaccines (including the flu shot)
  • Covering coughs and sneezes
  • Staying home when sick
  • Following the rules for standard and contact isolation
  • Using personal protective equipment the right way
  • Cleaning and disinfecting the environment,
  • Sterilising medical instruments and equipment
  • Following safe injection practices
  • Using antibiotics wisely to prevent antibiotic resistance.

What are the stages of infection?

The five stages of infection include the incubation, prodromal, illness, decline, and convalescence stage.

  • Incubation stage - the incubation period occurs in an acute disease after the initial entry of the pathogen into the host (patient). It is during this time the pathogen begins multiplying in the host.
  • Prodromal stage - During this phase, the pathogen continues to multiply, and the host begins to experience general signs and symptoms of illness, typically resulting from activation of the immune system, such as fever, pain, soreness, swelling, or inflammation.
  • Illness stage - The signs and symptoms of the disease are most evident and severe.
  • Decline stage - The number of pathogen particles begins to decrease, and the signs and symptoms of illness begin to decline.
  • Convalescence stage - During this stage, the patient generally returns to normal functions, although some diseases may inflict permanent damage that the body cannot fully repair.

Infectious diseases can be contagious during all five periods of infection.

Where can I find online training courses and qualifications for infection prevention?

The Mandatory Training Group is the leading UK provider of accredited statutory and mandatory training courses for all sectors, including health and social care, education, local government, private companies, charitable and third sector organisations.

Alternatively, you can contact our helpful Support Team byclicking hereto tell us your training courses and qualifications for infection prevention.

Online training courses and qualifications for infection prevention

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Frequently asked questions and answers about how to prevent infection?

Here at The Mandatory Training Group, we receive many questions about how to prevent infection. We have selected a few of these questions and answered them below.

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What Is the Chain of Infection? - The Mandatory Training Group UK -

What Is the Chain of Infection? - The Mandatory Training Group UK.

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