Infections are a common occurrence in Long Term Care (LTC) facilities. Residents who reside there are usually elderly, are in declining health and have comorbid chronic illnesses. More than one and a half million people reside in LTC facilities and as the acuity of illness has increased drastically, therefore, the risk of acquiring Healthcare Associated Infections (HAI) has also increased.
Residents are frequently transferred between LTC facilities and hospitals, providing additional dynamics to the transmission and acquisition of HAIs.
The causative agents of infections are microorganisms (germs). Bacteria, fungi, protozoa, viruses and parasites are the most common types. These are usually harmless in the environment. It takes thousands to cause disease and vary in infectivity (how easy are they to catch) and in virulence (the severity of illness from the infection they cause). Residents in LTC facilities are, as mentioned above, more susceptible to infection and their immune systems are weaker.
Bacteria are single cell organisms. All people live with many bacteria (normal flora) in their bodies. Usually they do not cause disease unless (1) their balance is disturbed or (2) they are moved to a part of the body where they do not belong or (3) to a new susceptible host.
Important bacteria causing human disease include:
- E. coli (urinary tract infections and diarrhea).
- Streptococcal (wound infections, cellulitis sepsis, and death)
- Clostridium difficile (severe diarrhea, colitis)
- Staphylococcus (skin boils, pneumonia, endocarditis sepsis, death).
- Mycobacterium (tuberculosis)
Fungi have a worldwide prevalence and healthy people are not usually affected. Fungi illnesses usually affect the skin, nails and subcutaneous tissue. Candida is a fungus that causes yeast infections. These are often seen in obese residents with pendulous breasts and abdominal folds.
Protozoa are also singled celled organisms but are larger than bacteria. The disease causing variety include amoebas, giardia and Pneumocystis carinii. The latter often causes pneumonia and may be fatal in immunocompromised individuals.
Viruses are intracellular parasites because they can reproduce inside a living cell. Some viruses, such as human immunodeficiency virus (HIV), hepatitis B (HBV) and hepatitis C (HCV) have the ability to enter and survive in the body for years before symptoms of the disease occur. These viruses can be transmitted to others before the source is aware they are infected.
The influenza virus makes its presence known quickly
through characteristic symptoms. All of these viruses are of concern in the healthcare setting.
Parasites are larger organisms that can infect or infest residents. Infestation with lice or scabies occur by direct contact and is highly contagious. Ingestion of the eggs of roundworm, tapeworms and pinworms can occur. Penetration of the skin or mucous membranes with their larvae can also cause infections.
We need to be aware of how infections occur and are transmitted. This process is called the Chain of Infection:
The causative organism (pathogen) has many paths for entering the human body and these are referred to the Port of Entry. This can be through the mouth, nose, eye, cuts, skin abrasions, surgical incisions, wounds, needle sticks and intravenous sites. Anatomical openings with tubes, such as gastrostomy tubes, tracheostomy tubes or surpapubic catheters can also be ports of entry as well as urinary tract catheters.
The reservoir is the person in whom the organism lives and multiplies. The gastrointestinal (GI) tract is the place in the body for many different types of organisms, including viruses, bacteria and parasites.
The mode of transmission is how the organism is transferred from the infected person to another person, who is named the susceptible host. The mechanisms by which the transmission may occur are as follows:
- The most common mode of transmission is unwashed hands.
- Direct contact is person-to-person transmission of the pathogens.
- Indirect contact is the spread of pathogens by a person or an inanimate go-between, such as unwashed hands and unclean instruments.
- Droplet transmission occurs by coughing, sneezing, and speaking and the pathogens can travel approximately three to six feet before dying off or falling on another surface.
- Airborne transmission can occur when respiratory droplets evaporate and are suspended in the air.
Diseases transmitted by this route are smallpox, tuberculosis chickenpox and measles.
The portal of Exit is the path by which the organism gets out of the reservoir. In a person, this is often by a bodily fluid. Blood, feces, nasal exudates, respiratory secretions and wound drainages are all examples of body fluids and how pathogens can exit the body. However, some bacteria, such a Methicillin Resistant Staphylococcus Aureus (MRSA) can live and grow on the skin.
Not all people who become infected with a pathogen have symptoms or signs of a disease at the time they transmit the infection to others, that person is asymptomatic and the transmission is referred to as asymptomatic transmission.
Some individuals are prone to becoming transiently or permanently colonized with organisms they have been exposed to. They may never develop symptoms of the infection but are an important source of transmission to others.
An endogenous infection occurs when a person becomes infected with microbes from their own natural flora, when their own germs get in the wrong place. For example, the urinary tract may become infected with microbes from the
GI tract, such as with Enterococcus (e-coli).
Due to the high occurrence of infections in LTC facilities, not just treatment but prevention is of the utmost importance. There are many standards and guidelines designed to proactively prevent the spread of infections.
Many states and most medical professional organizations
have designed standards of professional behavior and responsibility as the pertain to infection control.
Prevention and Control standards are a collaborative effort between the Centers for Disease Control (CDC),
the Joint Commision (JC), World Health Organisation (WHO), the Occupational Health and Safety Administration (OSHA). ( Further information on their standards may be obtained online at their individual websites.)
The immune system is the body’s defense mechanism against disease. In frail elderly or ill residents this may be compromised and these individuals are said to be immunocompromised. The immune system becomes less responsive with age. Nutritional status is a key factor in the immune system and a person who is poorly nourished may not be able to fight an infection. Also, gastric acid which is a natural barrier against invading organisms decrease with age. Certain medications can impair immunity.Anti- inflammatory drugs like corticosteroids, and cancer drugs can interfere with the immune system.
Infections and Infection Control is so diverse and of such vital importance that I will continue the subject in my blog over the next two months. I will discuss infection control precautions and what constitutes a good Infection Control Program and who should be responsible for it in the coming months.
When I was researching for this blog I came across “Wild Iris Medical Education” online. They had a fantastic course on Infection Control. I took the course, passed the examination and for a very reasonable fee, I got a certificate and 6 hours of Continuous Education credit. The course was well laid out with current information and was easy to comprehend. I would recommend it to any nurse. I will certainly revisit them for further continuing education programs.
