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Chain of Infection: What Is it and How to Break it

Kym Orange, Jr., Healthcare Segment Strategy and Marketing Manager, W.W. Grainger, Inc.

Healthcare exists in an ever-changing world, so there is a continuing need for medical professionals to be able to identify and address new and existing health issues. For example, it’s important to remember the links related to an infection in order to help prevent the spread of it.

The term “chain of infection” refers to the conditions (links) that must be met in order for an infectious disease to spread. The idea of breaking the chain of infection means stopping at least one of those links, thus preventing it from starting again. If unchecked, certain infections can spread rapidly through the chain.

Listed below are the six links in the chain of infection, as well as ways to break that chain.

  • Pathogen or infectious agent — the infection cause
  • Reservoir or carrier — the person, animal or environmental source
  • Portal of exit — the way the infection comes out of the body, such as through the respiratory tract, skin contact, mucus or blood
  • Means of transmission — how it is spread or passed along, which can be:
    • Direct transmission – from contact or droplets in the air
    • Indirect transmission — can be airborne, vehicle-borne (food, water, blood) or vector-borne (ticks, fleas, mosquitoes and other sources)
  • Portal of entry — the portal of exit is also commonly the portal of entry; that is, where the infection originates in one host and moves to another
  • New host — the next person to get the infection (starting the new chain)

One scientific approach to breaking the infection chain is to reduce the likelihood of a reservoir (or carrier) of the infection. For instance, scientists in the United States are growing dengue fever–resistant mosquitoes in the lab. Since mosquitoes are known reservoirs for spreading dengue fever, the scientists are trying to remove this link in the chain of infection. While that is a more technical and long-term project, there are also simple ways to effectively reduce the spread of infection, many of which are already part of hospitals’ and healthcare centers’ overall procedures. It is necessary for everyone in the healthcare system to follow these protocols, from doctors and nurses to environmental service technicians, facilities engineers, and administrators.

Keep in mind that if the reservoir cannot pass along the infection, or if the portal of entry/exit does not reach a new host, then the chain of infection is broken. That means the infection will be more difficult to contract and spread.

Here are ways to help reduce the spread of airborne infections:

  • Control air pressure to ensure a clean-air environment.
  • Monitor and measure air pressure.
  • Use HEPA filters to remove airborne particles.
  • Set physical barriers.

For instance, hospitals may use temporary barriers and isolation areas to limit further exposure of an infection within a building.

“Engineering controls can be effective in reducing infection risks; maintaining critical pressure relationships to separate clean and dirty areas is one such key measure that hospitals can take,” says Leo Old, Health and Safety Engineering Consultant of Ensafe.    

A past survey from the Association for Professionals in Infection Control and Epidemiology noted that measuring compliance with prevention practice is one of the greatest challenges when dealing with infections. This points out how compliance plays a vital role in managing infections in hospitals and other locations (long-term care facilities, pharmacy clinics, etc.).

The Centers for Disease Control and Prevention (CDC) offers several free resources and training materials that explain how to prevent infection. Part of the CDC, the National Institute for Occupational Safety and Health (NIOSH), provides a list of potential diseases and emerging infectious diseases, and additional background on each, for a better understanding of each chain of infection. For example, there are resources for understanding the Avian influenza, West Nile Virus, and Ebola, among others.

Perseverance is key when it comes to identifying the chain of infection and ultimately preventing or stopping it from spreading.

Kym Orange Jr. is an accomplished healthcare strategy, marketing and sales professional with experience in strategic planning, employee development, sales and marketing, and business management. His current responsibility and focus since 2011 includes creating unique healthcare value through insight-driven solutions and ensuring the delivery of positive customer experiences through various Grainger business channels. Kym holds a BA from Indiana University in Bloomington, IN.

Resources and Links:

The information contained in this article is intended for general information purposes only and is based on information available as of the initial date of publication. No representation is made that the information or references are complete or remain current. This article is not a substitute for review of current applicable government regulations, industry standards, or other standards specific to your business and/or activities and should not be construed as legal advice or opinion. Readers with specific questions should refer to the applicable standards or consult with an attorney.

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