Infection control terms

24 terms

Airborne precautions: Precautions for infections spread by small particles that stay suspended in the air and travel long distances, such as tuberculosis, measles and varicella. Place the client in a negative-pressure airborne infection isolation room with the door closed. Everyone entering wears a fit-tested N95 or higher-level respirator, and the client wears a surgical mask outside the room. Nonimmune staff should not enter for measles or varicella.
Antimicrobial resistance: The ability of bacteria, viruses, fungi and parasites to stop responding to antimicrobial drugs, named by WHO as one of the top global public health threats. Unnecessary and inappropriate antibiotic use accelerates it. Nurses support antimicrobial stewardship: collect cultures before antibiotics, give doses on time, teach clients to complete therapy as prescribed and follow infection-control precautions.
Aseptic technique: Practices that keep microorganisms from reaching the client, the environment or sterile supplies. Medical asepsis (clean technique) reduces the number of microorganisms; surgical asepsis (sterile technique) keeps items free of all microorganisms and is used for procedures such as catheter insertion and surgical wound care. Keep a sterile field above waist level and in view, and treat its outer 1-inch (2.5 cm) border as nonsterile.
Catheter-associated urinary tract infection: A urinary tract infection in a client with an indwelling urinary catheter; one of the most common healthcare-associated infections, with risk rising every day the catheter stays in. The most effective prevention is avoiding unnecessary catheters and removing them as soon as they are no longer needed. Insert with sterile technique, keep the drainage system closed, keep the bag below the bladder, prevent kinks and provide perineal care.
Central line-associated bloodstream infection: A bloodstream infection in a client with a central venous catheter that is not explained by another source; a serious and costly healthcare-associated infection. The prevention bundle covers maximal sterile barriers and chlorhexidine skin antisepsis at insertion, appropriate site selection, scrubbing the hub before every access, keeping the dressing clean and dry, and reviewing the need for the line every day.
Chain of infection: The six linked elements needed for an infection to occur: infectious agent, reservoir, portal of exit, mode of transmission, portal of entry and susceptible host. Breaking any link prevents infection; for example, hand hygiene targets transmission, vaccination the susceptible host and a sterile dressing the portal of entry. Most nursing infection-prevention practices aim to break one of these links.
Clostridioides difficile infection: A bowel infection caused by toxins of the spore-forming bacterium Clostridioides difficile, ranging from watery diarrhea to severe colitis; recent antibiotic use is the main risk factor. Spores resist alcohol, so wash hands with soap and water, clean with a sporicidal (e.g., bleach-based) disinfectant and use contact precautions. Monitor stool frequency and fluid balance.
Contact precautions: Precautions for organisms spread by direct contact or indirectly through the client's environment, such as MRSA, VRE, Clostridioides difficile, infected wounds and some diarrheal illnesses. Use a single room when possible; put on a gown and gloves when entering and remove them before leaving. Dedicate equipment such as stethoscopes and blood pressure cuffs to the client, or disinfect it after use.
COVID-19: An infectious disease caused by the SARS-CoV-2 virus, mainly affecting the respiratory tract and ranging from mild upper respiratory symptoms to severe pneumonia and multiorgan failure. It spreads through droplets and aerosols. Older adults, people with chronic conditions and immunocompromised people are at risk of severe disease. Monitor respiratory status and oxygen saturation, apply transmission precautions per facility protocol and support vaccination.
Droplet precautions: Precautions for infections spread by large respiratory droplets that travel only a short distance when a person coughs, sneezes or talks, such as influenza, pertussis, mumps and meningococcal disease. Place the client in a single room or apart from others, and wear a surgical mask on entering. If the client must leave the room, they wear a surgical mask. No special ventilation is needed.
Hand hygiene: The single most effective way to prevent healthcare-associated infections. WHO's five moments are before touching a client, before an aseptic procedure, after body fluid exposure risk, after touching a client and after touching the client's surroundings. An alcohol-based hand rub takes 20–30 seconds and washing with soap and water 40–60 seconds; use soap and water when hands are visibly soiled and for Clostridioides difficile or norovirus.
Healthcare-associated infection: An infection that develops while receiving health care and was neither present nor incubating on admission; in hospitals, infections beginning 48 hours or more after admission are generally counted. The most common are catheter-associated urinary tract and bloodstream infections, ventilator-associated pneumonia, surgical site infections and Clostridioides difficile infection. Most are preventable with hand hygiene and evidence-based care bundles.
Hepatitis B: A liver infection caused by hepatitis B virus, spread through blood, sexual contact and from mother to infant; chronic infection can lead to cirrhosis and liver cancer. A safe, effective vaccine exists: in Türkiye it is part of the schedule starting at birth, and it is recommended for all health workers. Infants of HBsAg-positive mothers receive vaccine and hepatitis B immune globulin as soon as possible after birth. Standard precautions are sufficient for care.
HIV infection: Infection with the human immunodeficiency virus, which destroys CD4+ T lymphocytes and weakens the immune system; untreated, it progresses to AIDS with opportunistic infections. It spreads through blood, sexual contact and from mother to child during pregnancy, birth or breastfeeding. With antiretroviral therapy that suppresses the virus, people live healthy lives and do not transmit HIV sexually. Standard precautions are sufficient; support adherence and challenge stigma.
Methicillin-resistant Staphylococcus aureus: A strain of Staphylococcus aureus resistant to methicillin and several other antibiotics. It causes infections ranging from skin and soft tissue infections to pneumonia and sepsis, and silent colonization is common. It spreads mainly by contact with hands and contaminated surfaces. In hospital, use contact precautions, meticulous hand hygiene and environmental cleaning.
Neutropenic precautions: Measures that protect a client whose absolute neutrophil count is low (below 500/mm³ is severe neutropenia) and who is highly vulnerable to infection. Key measures are meticulous hand hygiene, a private room when possible, keeping staff and visitors with signs of infection away, well-cooked and safe food, and no fresh flowers or potted plants in the room. Fever in a neutropenic client is an emergency, and the weakened inflammatory response can hide signs of infection such as redness, swelling or pus.
Personal protective equipment: Equipment such as gloves, gowns, masks, respirators, goggles and face shields that protects staff and clients from infectious agents, chosen according to the expected exposure. The CDC sequence for putting it on is gown, mask or respirator, goggles or face shield, then gloves; for taking it off, gloves, goggles or face shield, gown, then mask or respirator. Perform hand hygiene immediately after removing PPE.
Sharps injury: An occupational injury from a needle, scalpel or other sharp that can transmit hepatitis B, hepatitis C and HIV. To prevent it, never recap needles, use safety-engineered devices and discard sharps immediately into puncture-resistant containers that are not overfilled. After an injury wash the site with soap and water without squeezing, report it at once and get prompt evaluation for post-exposure prophylaxis.
Standard precautions: The basic infection-control practices used in the care of every client, whatever their diagnosis or infection status; they replaced the older universal precautions. They assume that all blood, body fluids, secretions, excretions (except sweat), nonintact skin and mucous membranes may be infectious. They include hand hygiene, PPE matched to the expected exposure, respiratory hygiene and cough etiquette, safe injection practices, safe sharps handling and environmental cleaning.
Sterilization and disinfection: Sterilization destroys all microorganisms, including spores; disinfection destroys most microorganisms but not spores. Under the Spaulding classification, critical items that enter sterile tissue or the vascular system are sterilized, semicritical items that touch mucous membranes need high-level disinfection, and noncritical items that touch intact skin get low-level disinfection. Visible soil is cleaned off before either process.
Surgical site infection: An infection at the incision or in the organ or space operated on, within 30 days of surgery, or up to 90 days for certain procedures such as joint replacement. Redness, warmth, swelling, increasing pain, purulent drainage and fever are typical. Prevention includes a preoperative shower, clipping rather than shaving when hair must be removed, timely antibiotic prophylaxis, normothermia, glucose control and aseptic wound care.
Transmission-based precautions: Precautions added to standard precautions according to how a known or suspected infection spreads: contact, droplet and airborne precautions. Start them on the basis of symptoms, before the diagnosis is confirmed. Post signage at the door, dedicate equipment to the client where possible and take the client out of the room only when necessary. Watch for loneliness and anxiety caused by isolation.
Tuberculosis: An airborne infection caused by Mycobacterium tuberculosis, usually affecting the lungs. A cough lasting two weeks or more (WHO; the CDC uses three weeks), sputum, hemoptysis, night sweats, fever and weight loss are typical; latent infection causes no symptoms and is not contagious. Sputum tests (a rapid molecular test, smear and culture) confirm the diagnosis, and the tuberculin skin test or IGRA screens for infection. Active pulmonary TB needs airborne precautions and long multidrug therapy given as directly observed therapy.
Ventilator-associated pneumonia: Pneumonia that develops in a mechanically ventilated client 48 hours or more after intubation. The prevention bundle includes raising the head of the bed to 30–45° unless contraindicated, regular oral care, daily sedation interruption with assessment of readiness to extubate, subglottic secretion drainage and avoiding unnecessary opening of the ventilator circuit.