Viruses and Viral Illnesses

• Viruses are non-living organisms that rely on a host to survive, lacking characteristics of living organisms despite being able to endure outside a host.

Viral Illnesses

• Viral illnesses vary widely in symptoms and severity and are common in long-term care settings.
• Viral illnesses include influenza (flu), SARS-CoV-2 (COVID-19), Norovirus gastroenteritis, and common colds.
• Antibiotics are ineffective against viral infections and should not be used unless there is a bacterial infection.
• Inappropriate antibiotic use contributes to multi-drug resistant infections.

Common Viruses: Influenza

• The flu is caused by influenza viruses that affect the respiratory system.
• Symptoms include fever, cough, sore throat, runny nose, muscle aches, headaches, and fatigue.
• The flu can be severe, especially in the very young, the very old, and immunocompromised individuals.
• Treatment includes antiviral medications, increased fluid intake, rest, and medications for symptom relief.
• Prevention involves an annual vaccine targeting the most prevalent influenza strains, hand hygiene, and cough etiquette.

Common Viruses: Viral Respiratory Pathogens

• Viral respiratory pathogens are common in long-term care facilities, causing illnesses from mild colds to severe pneumonia.
• SARS-CoV-2 is the virus that causes COVID-19.
• COVID-19 symptoms include fever, cough, shortness of breath, fatigue, muscle aches, headache, loss of taste or smell, sore throat, congestion, nausea, and diarrhea.
• Symptoms may appear 2-14 days after exposure where some people may be asymptomatic, yet still infectious.
• Older adults and those with underlying conditions are at higher risk for severe complications.
• COVID-19 symptoms are managed with antipyretics, inhaled steroids, and anti-inflammatories, with treatment options rapidly evolving.

Common Viruses: Norovirus

• Norovirus gastroenteritis causes a severe stomach bug and spreads easily through direct contact.
• Symptoms include diarrhea, vomiting, nausea, and stomach pain, appearing 12-48 hours after exposure and lasting up to three days.
• No specific treatment exists for Norovirus infection, but severe cases may require IV fluids.
• Prevention includes hand hygiene, washing produce, avoiding food preparation when sick, disinfecting surfaces, and thorough laundry washing.

Fungi

• Fungi and fungal spores are ubiquitous, generally harmless, with some capable of causing illness.
• Fungal infections are often treatable with antifungal medications.
• Fungal infections can occur post-antibiotic use due to the elimination of beneficial bacteria.

Fungal Infection Examples

• Ringworm
• Jock Itch (male genitalia)
• Vaginal yeast infections (female genitalia)
• Thrush (mouth and throat)
• Diaper Rash
• Athlete's foot
• Fungal nail infections
• Infections like Pneumocystis jirovecii pneumonia (PCP), Invasive Candidiasis, Candida auris, and Aspergillosis pose more risk to those with weakened immune systems.
• Candida auris is a multi-drug resistant fungal infection found in nursing homes.

Parasites: Ectoparasites

• Ectoparasites are multi-celled organisms needing a living host, biting or burrowing into the skin.
• Ectoparasites sometimes act as vectors, spreading diseases.
• Common ectoparasite infestations in long-term care settings include scabies, lice, and fleas.

Common Parasites: Scabies

• Scabies infestations are caused by mites burrowing into the skin and laying eggs, leading to itching and a rash.
• The rash resembles small pimples and appears on wrists, elbows, armpits, waist, buttocks, and shoulder blades.
• Scabies spreads through direct, prolonged skin contact.
• Infestations may not be apparent for up to two months post-infection.
• Future infections can be noticed in 1-4 days.
• Treatment includes scabicide lotions or creams.
• Secondary infections at scratch sites may require further treatment.
• CNAs should report any rash or itching to the nurse if scabies is suspected.

Chain of Infection Overview

• The chain of infection involves 6 links essential for spreading communicable diseases.
• Breaking any link can hinder disease transmission.

Chain of Infection: Pathogen

• Pathogens are microorganisms causing disease, including bacteria, viruses, fungi, and parasites.
• A pathogen's ability to infect depends on its pathogenicity, degree of virulence, and transmissibility.

Chain of Infection: Reservoir

• A reservoir is where a pathogen lives, replicates, and thrives, like humans, animals, or the environment.

Chain of Infection: Human Reservoirs

• Human reservoirs can be symptomatic or asymptomatic.
• Symptomatic infections have recognizable signs, leading to restricted activities to prevent spread.
• Asymptomatic infections lack signs/symptoms, making them less recognizable but still capable of spreading disease.

Chain of Infection: Animal & Insect Reservoirs

• Zoonotic diseases are transmitted naturally from animals to humans, such as Lyme disease and rabies.
• Salmonella spreads through raw meats, eggs, and dairy.

Chain of Infection: Environmental Reservoirs

• Environmental reservoirs breed infectious diseases.
• Soil is a reservoir for Clostridium tetani (tetanus), and water for Legionella pneumophila (Legionnaire's disease).

Chain of Infection: Portal of Exit

• The Portal of Exit is the pathogen's escape route from the reservoir, based on the reservoir's characteristics.

Human Portals of Exit

• Alimentary: vomiting, diarrhea, saliva
• Genitourinary: sexual contact
• Respiratory: secretions from coughing, sneezing, or talking
• Skin: open wounds

Mode of Transmission: Direct Contact

• Direct contact is person-to-person.

Examples of Direct Contact Mode

• Skin-to-skin contact
• Kissing
• Sexual contact
• Contact with oral secretions
• Contact with body lesions
• Pathogens spread by direct contact include Gonorrhea, Mononucleosis, Bacterial Conjunctivitis, and COVID-19.

Mode of Transmission: Droplet

• Droplet transmission moves pathogens through the air in droplets of body secretions.
• Droplets travel 3-6 feet and settle on surfaces, remaining spreadable.
• Transmission occurs via inhalation of droplets, droplets entering mucous membranes, or touching contaminated surfaces then touching the face.
• Illnesses caused by droplet transmission are Strep Throat, Influenza (flu), the common cold, and COVID-19.

Mode of Transmission: Blood-Borne

• Blood-borne pathogens transmit directly through blood when infected blood enters a host's blood, mucous membranes, or open wounds.

Examples of blood-borne pathogens

• Human Immunodeficiency Virus (HIV)
• Hepatitis-B Virus
• Hepatitis-C Virus

Mode of Transmission: Airborne

• Airborne transmission occurs when pathogens smaller than five microns remain suspended in the air.
• A person entering the space can become infected.
• Measles and tuberculosis are airborne illnesses, with measles lasting up to 18 hours and tuberculosis up to six hours in the air.

Mode of Transmission: Vector

• Vector transmission uses insects to transport pathogens.
• Insects transmit bacteria or viruses through bites.

Examples of Vector Mode

• Mosquito: West Nile Virus
• Fleas: Bubonic Plague (Yersinia pestis)
• Ticks: Lyme Disease ( Borrelia burgdorferi )

Chain of Infection: Portal of Entry

• The Portal of Entry is the route a pathogen uses to enter the body.

Examples of Portals of Entry

• Inhalation (via the respiratory tract)
• Absorption (via mucous membranes such as the eyes)
• Ingestion (via the gastrointestinal tract)
• Inoculation (as the result of an inoculation injury)
• Introduction (via the insertion of medical devices)

Chain of Infection: Susceptible Host

• The susceptible host is the organism affected by the disease transmitted through the chain of infection.
• Susceptibility depends on age, health status, medication usage, and general resistance factors.

Breaking the Chain

• To break the spread of infection, interventions can control or eliminate the virus, protect portals of entry, and boost the person's natural defenses.

Breaking the Chain: Controlling the Source of Transmission

• Stopping infectious disease spread at the source is important, starting with identifying the infection's cause for proper treatment.
• Bacterial infections can be treated with antibiotics to prevent spread.
• Cooking food to safe temperatures kills bacteria and spores.

Breaking the Chain: Protect Portals of Entry

• Interventions protect portals of entry.
• Protective measures prevent communicable diseases from spreading.

Examples of how to protect Portals of Entry

• Using proper PPE during known exposure to a pathogen
• Consistently practicing hand hygiene
• Isolating infectious individuals and minimizing contact
• Filtering air or changing the airflow in a room using negative pressure.

Breaking the Chain: Increasing the Resident's Defense

• Increasing a person's defense allows the immune system to resist pathogens.
• Vaccines help the body develop antibodies.
• Prophylactic drug use for high-risk patients can prevent a pathogen from gaining ground.
• Herd immunity occurs when many people are immune to a pathogen, usually via vaccination, hindering its spread.
• Vaccines teach the body to recognize and fight germs.