Disease transmission

by Noel Kelsch, RDHAP
[email protected]

When my children where younger, I had mixed feelings about long car trips. I loved singing and playing I Spy and license plate games, but after a few hundred miles, it always seemed like someone would say something as profound as "She's breathing on me!" I always gave my kids a roll of quarters when we got in the car for our adventures. Each time I had to reprimand them, they had to hand me a quarter. Whatever was left after the trip they got to spend. Great investment! On one particular trip, my youngest daughter got in the car and handed me her roll of quarters. She said, "Here. It's too much pressure." My kids are grown now, but from time to time I still reflect on those moments.

Following standard precautions, we have to treat every patient as if he or she is a possible source of disease. Focusing our efforts on the modes of transmission can help us limit exposure. Microorganisms can be transmitted from one person to another by four different means: direct contact, indirect contact, droplet infection, and airborne infection.

Direct contact ► Spreading pathogens from one host to another through close association between the hosts. Also known as person-to-person contact, there is no intermediate object involved.1

An example in the dental setting: A patient presents with a herpetic lesion on the lip, and treatment is rendered. At one point, the ungloved clinician accidentally touches the lesion. There is a small abraded area on the clinician's finger. The clinician develops herpes whitlow on that finger.

Solutions: Evaluate all patients for transmittable diseases before rendering treatment. Do not allow patients with herpetic lesions to receive treatment unless it is an emergency. Wear personal protective equipment, creating a barrier between you and the patient.

Indirect contact ► Spreading of pathogens by fomites (see box above), and contact with items contaminated with a patient's microorganisms, such as surfaces, hands, and sharps.

An example in the dental setting: A child comes in with conjunctivitis. He touches his eye and then touches the mirror during patient education. The clinician touches the mirror barehanded and then touches her eye, acquiring conjunctivitis.

Solutions: Evaluate all patients for transmittable diseases before rendering treatment. Do not allow patients with conjunctivitis to enter the operatory. Use barrier protection for all surfaces; wear personal protective equipment in the operatory until the areas and equipment have been sanitized. Wash your hands any time you touch a contaminated object.

Droplet infection ► Spreading pathogens by large particle droplets carrying microorganisms.

An example in the dental setting: A patient presents with influenza, and treatment is rendered. The clinician does not wear her mask properly and droplet particles and splatter are able to enter the nasal cavity and contaminate the mucous membrane. The clinician gets influenza.

Solutions: Evaluate all patients for transmittable diseases before rendering treatment. Do not allow patients with influenza to receive treatment unless it is an emergency. Wear your personal protective equipment properly. Change your mask frequently and dispose of it between patients to eliminate moisture and contamination.

Airborne infection ►Spread of pathogens (droplet nuclei) that are smaller than 5 mm. They can remain in the air for a long period of time and can be inhaled.1

An example in the dental setting: Patient presents with a case of varicella (chicken pox), including lesions in the nose. The patient sneezes and the clinician breathes in the virus. The clinician has not been vaccinated and thus develops varicella.

Solutions: Evaluate all patients for transmittable diseases before rendering treatment. Do not allow patients with varicella to receive treatment unless it is an emergency. Wear personal protective equipment properly. If you suspect an airborne disease, wear an N-95 respirator. Surgical masks do not have a filtration system to filter particles that small.

Tip for prevention of disease transmission and maximizing production

When confirming patients for dental appointments, ask them these questions:

Has anything changed regarding your health since we saw you last?
Have you had any recent surgeries or hospitalizations?
Do you need to premedicate for dental treatment?
Are you currently healthy?

Asking these four simple questions will help eliminate wasted chairtime and exposure to pathogens.

A lot of stress is placed upon us to make sure that we are doing everything to keep both patient and clinician safe. You can keep your roll of quarters by following the standard precautions, which will eliminate the stress and reward you and your patients with a safe, disease-free environment.

What is a fomite?

A fomite is an inanimate object or substance that is capable of transmitting infectious organisms from one individual to another. In the dental setting this could include contaminated syringes, instruments, countertops, pens, clothing, magazines, and care delivery trays. All of these objects must be properly treated to remove any chance of cross-contamination between patients and during treatment.

Noel Brandon Kelsch, RDHAP, is a syndicated columnist, writer, speaker, and cartoonist. She is a member of the Organization for Safety, Asepsis and Prevention, and has received many national awards. Kelsch owns her dental hygiene practice that focuses on access to care for all. She has devoted much of her 35 years in dentistry to educating people about the devastating effects of methamphetamine and drug use. She is immediate past president of the California Dental Hygienists' Association, and is on the board of directors for the Simi Valley Free Clinic.