Infectious Disease Abbreviations
92 abbreviations · part of Medical Abbreviations
Abbreviations for infections and the organisms that cause them, HIV care, sexually transmitted infections, viral hepatitis, tuberculosis, drug-resistant bacteria, hospital infection control and adult vaccines. They appear in infectious disease consult notes, microbiology reports, public health alerts and infection prevention dashboards. Organism names are conventionally italicized in full (Staphylococcus aureus) and abbreviated after first use (S. aureus), while surveillance terms such as CLABSI and CAUTI follow CDC National Healthcare Safety Network definitions.
| Abbreviation | Stands for | Description |
|---|---|---|
| ACIP | Advisory Committee on Immunization Practices | Federal advisory committee that recommends how vaccines licensed by the FDA should be used in the US civilian population, including which ages and groups should receive… |
| AIDS | Acquired immunodeficiency syndrome | The most advanced stage of HIV infection, diagnosed when the CD4 count falls below 200 cells/mm3 or an AIDS-defining illness occurs, such as Pneumocystis pneumonia… |
| AMR | Antimicrobial resistance | Ability of bacteria, viruses, fungi and parasites to survive medicines designed to kill them, driven by overuse and misuse of antimicrobials in humans and animals. |
| ARF | Acute rheumatic fever | Autoimmune inflammatory illness that follows untreated group A streptococcal throat infection by two to four weeks, affecting the joints, heart, skin and brain. |
| ART | Antiretroviral therapy | Combination of medicines from at least two drug classes that suppresses HIV replication, restores immune function and prevents transmission. |
| ASP | Antimicrobial stewardship program | Coordinated hospital or clinic program, usually led by an infectious disease physician and pharmacist, that improves antibiotic use through audits, feedback, approval… |
| BCG | Bacillus Calmette-Guérin | Live attenuated vaccine made from Mycobacterium bovis, given at birth in many countries to protect young children against severe forms of tuberculosis such as TB… |
| BSI | Bloodstream infection | Infection in which bacteria or fungi are found in blood cultures with corresponding illness. |
| C. diff | Clostridioides difficile | Spore-forming gut bacterium whose toxins cause diarrhea and colitis, usually after antibiotics disrupt normal gut flora. |
| CD4 | Cluster of differentiation 4 (CD4 T-cell count) | Count of helper T lymphocytes in the blood, normally about 500–1,500 cells/mm3, used to stage HIV infection and decide on preventive treatment. |
| CDI | Clostridioides difficile infection | Clinical and surveillance term for diarrhea or colitis with a positive C. difficile toxin or molecular test. |
| CMV | Cytomegalovirus | Common herpesvirus that infects most adults, usually without symptoms, and stays latent for life. |
| COVID-19 | Coronavirus disease 2019 | Disease caused by the SARS-CoV-2 coronavirus, ranging from no symptoms to severe pneumonia, blood clots and multiorgan failure, with lasting symptoms (long COVID) in… |
| CRAB | Carbapenem-resistant Acinetobacter baumannii | Highly drug-resistant Acinetobacter that survives for long periods on hospital surfaces and causes ventilator-associated pneumonia, bloodstream and wound infections… |
| CRE | Carbapenem-resistant Enterobacterales | Gut bacteria such as Klebsiella pneumoniae and E. coli that resist carbapenems, the antibiotics of last resort for many infections, often by producing carbapenemase… |
| CT | Chlamydia trachomatis | Bacterium causing chlamydia, the most commonly reported bacterial STI in the US, which is often silent but can lead to pelvic inflammatory disease, ectopic pregnancy… |
| DAA | Direct-acting antiviral | Class of oral hepatitis C drugs that block specific viral proteins (NS3/4A protease, NS5A or NS5B polymerase), curing most infections with few side effects. |
| DOT | Directly observed therapy | Strategy in which a health worker watches a patient take each dose of TB medicine, in person or by video, to ensure adherence and prevent drug resistance. |
| E. coli | Escherichia coli | Gut bacterium that is mostly harmless but includes strains causing the majority of urinary tract infections, many bloodstream infections and neonatal meningitis, as… |
| EBV | Epstein-Barr virus | Herpesvirus that infects more than 90 percent of adults worldwide and causes infectious mononucleosis, with fever, sore throat, swollen lymph nodes and fatigue… |
| EPT | Expedited partner therapy | Practice of giving patients medication or a prescription to deliver to their sex partners, without the partners being examined, to treat chlamydia, gonorrhea or… |
| ESBL | Extended-spectrum beta-lactamase | Bacterial enzymes, most often produced by E. coli and Klebsiella, that break down penicillins and most cephalosporins, including ceftriaxone. |
| FUO | Fever of unknown origin | Prolonged fever of 38.3°C (101°F) or higher on several occasions, lasting at least three weeks, without a diagnosis after an appropriate initial evaluation. |
| GAS | Group A Streptococcus | Streptococcus pyogenes, the cause of strep throat, scarlet fever, impetigo and cellulitis, and of rare but life-threatening invasive infections such as necrotizing… |
| GC | Gonococcus (gonorrhea) | Clinical shorthand for Neisseria gonorrhoeae, the bacterium that causes gonorrhea, an STI of the urethra, cervix, rectum and throat. |
| GNR | Gram-negative rods | Microbiology description of rod-shaped bacteria that stain pink with Gram stain, including E. coli, Klebsiella, Pseudomonas, Enterobacter and Proteus. |
| GPC | Gram-positive cocci | Microbiology description of round bacteria that stain purple on Gram stain. |
| H1N1 | Influenza A virus subtype H1N1 | Subtype of influenza A named for its hemagglutinin type 1 and neuraminidase type 1 surface proteins. |
| H5N1 | Influenza A virus subtype H5N1 | Highly pathogenic avian influenza virus that causes massive outbreaks in wild birds and poultry and occasionally infects mammals and humans. |
| HAART | Highly active antiretroviral therapy | Term coined in the mid-1990s for the then-new combinations of three or more antiretroviral drugs, including protease inhibitors, that dramatically cut AIDS deaths. |
| HAP | Hospital-acquired pneumonia | Pneumonia that develops 48 hours or more after hospital admission and was not incubating at the time of admission, excluding patients on mechanical ventilation, whose… |
| HAV | Hepatitis A virus | Virus spread by the fecal-oral route through contaminated food, water or close contact, causing acute hepatitis with fever, nausea and jaundice. |
| HBsAg | Hepatitis B surface antigen | Protein on the surface of hepatitis B virus whose presence in blood indicates current infection, either acute or chronic. |
| HBV | Hepatitis B virus | DNA virus spread through blood, sex and from mother to baby at birth, causing acute or chronic hepatitis. |
| HCV | Hepatitis C virus | Bloodborne RNA virus that causes chronic hepatitis in most people infected, often silently for decades, leading to cirrhosis and liver cancer. |
| HIV | Human immunodeficiency virus | Retrovirus that infects CD4 T cells and, without treatment, gradually destroys the immune system, leading to AIDS. |
| hMPV | Human metapneumovirus | Respiratory virus related to RSV that causes colds, bronchiolitis and pneumonia, mainly in young children, older adults and people with weakened immunity. |
| HPV | Human papillomavirus | Group of more than 200 related viruses, about 40 of which infect the genital area; it is the most common sexually transmitted infection, and most sexually active people… |
| HSV | Herpes simplex virus | Virus with two types that cause lifelong infection with recurring outbreaks of blisters and sores: HSV-1 usually affects the mouth (cold sores) and HSV-2 the genitals… |
| HZ | Herpes zoster | Painful, blistering rash caused by reactivation of the varicella-zoster virus, usually confined to one dermatome on one side of the body. |
| IDSA | Infectious Diseases Society of America | Professional society representing infectious disease physicians, scientists and other specialists, best known for its clinical practice guidelines on infections such as… |
| IGRA | Interferon-gamma release assay | Blood test for TB infection that measures interferon-gamma released by a person's white cells when exposed to TB-specific proteins. |
| IIV | Inactivated influenza vaccine | Injected flu vaccine containing killed or split virus components, recommended every year for everyone six months and older. |
| ILI | Influenza-like illness | Surveillance definition of a fever of 100°F (37.8°C) or higher together with cough or sore throat, without another known cause. |
| IRIS | Immune reconstitution inflammatory syndrome | Paradoxical worsening of an infection, or unmasking of a hidden one, after antiretroviral therapy restores the immune system in people with advanced HIV. |
| KS | Kaposi sarcoma | Cancer of the cells lining blood and lymph vessels, caused by human herpesvirus 8 (HHV-8), that produces purple, red or brown patches and nodules on the skin, mouth and… |
| LAIV | Live attenuated influenza vaccine | Nasal spray flu vaccine (FluMist) containing weakened viruses that replicate in the cooler nose but not the lungs. |
| LTBI | Latent tuberculosis infection | Infection with TB bacteria that the immune system holds in check, producing no symptoms and no spread to others. |
| MAC | Mycobacterium avium complex | Group of environmental nontuberculous mycobacteria that cause disseminated infection in advanced HIV (CD4 below 50) and chronic lung disease in people with… |
| MDR-TB | Multidrug-resistant tuberculosis | Tuberculosis resistant to at least isoniazid and rifampin, the two most powerful first-line drugs. |
| MDRO | Multidrug-resistant organism | Umbrella term for bacteria resistant to several classes of antibiotics, including MRSA, VRE, CRE, ESBL producers and resistant Pseudomonas and Acinetobacter. |
| MERS | Middle East respiratory syndrome | Severe respiratory illness caused by MERS-CoV, a coronavirus first identified in Saudi Arabia in 2012 and acquired mainly from dromedary camels. |
| MIC | Minimum inhibitory concentration | Lowest concentration of an antibiotic or antifungal that prevents visible growth of a microorganism in the laboratory. |
| MRSA | Methicillin-resistant Staphylococcus aureus | Staph strains resistant to methicillin and nearly all other beta-lactam antibiotics, including penicillins and most cephalosporins. |
| MSM | Men who have sex with men | Epidemiologic term that describes sexual behavior rather than identity, used in HIV and STI surveillance, prevention guidelines and research. |
| MSSA | Methicillin-susceptible Staphylococcus aureus | Staph aureus strains that remain susceptible to anti-staphylococcal beta-lactams. |
| N95 | N95 filtering facepiece respirator | Tight-fitting disposable respirator certified by the US National Institute for Occupational Safety and Health (NIOSH) to filter at least 95 percent of airborne… |
| NHSN | National Healthcare Safety Network | CDC surveillance system used by tens of thousands of US hospitals, dialysis centers, nursing homes and other facilities to report healthcare-associated infections… |
| NSTI | Necrotizing soft tissue infection | Rapidly spreading infection that destroys skin, fat, fascia or muscle, including necrotizing fasciitis and Fournier gangrene. |
| NTM | Nontuberculous mycobacteria | Environmental mycobacteria other than the tuberculosis complex and leprosy bacillus, found in soil and water, that cause chronic lung infections in people with… |
| OI | Opportunistic infection | Infection caused by organisms that rarely make healthy people seriously ill but exploit a weakened immune system, as in advanced HIV, transplant recipients and… |
| OPAT | Outpatient parenteral antimicrobial therapy | Delivery of intravenous antibiotics outside the hospital, at home, in infusion centers or skilled nursing facilities, typically through a PICC line. |
| PAPR | Powered air-purifying respirator | Battery-powered respirator that blows filtered air into a loose-fitting hood or tight facepiece, providing high protection against airborne infections without fit… |
| PCP | Pneumocystis pneumonia | Fungal lung infection caused by Pneumocystis jirovecii, seen in people with CD4 counts below 200, transplant recipients and patients on long-term steroids. |
| PEP | Post-exposure prophylaxis | Short course of antiretroviral drugs started within 72 hours after a possible HIV exposure, such as a needlestick injury, sexual assault or condom failure, to prevent… |
| PHN | Postherpetic neuralgia | Persistent nerve pain lasting three months or more in the area of a shingles rash after it has healed. |
| PLWH | People living with HIV | Person-first term used in public health, research and clinical guidelines for people who have HIV infection. |
| PPD | Purified protein derivative (tuberculin skin test) | Extract of tuberculin injected into the skin of the forearm to test for TB infection; the raised, hardened area (induration) is measured 48–72 hours later. |
| PPSV23 | 23-valent pneumococcal polysaccharide vaccine | Pneumococcal vaccine (Pneumovax 23) covering 23 serotypes of Streptococcus pneumoniae, made from purified capsular sugars. |
| PrEP | Pre-exposure prophylaxis | HIV prevention method in which HIV-negative people take antiretroviral medicine before possible exposure, either as a daily pill or long-acting injection. |
| RMSF | Rocky Mountain spotted fever | Tick-borne bacterial infection caused by Rickettsia rickettsii, producing fever, headache and a rash that often starts at the wrists and ankles and spreads to the palms… |
| RSV | Respiratory syncytial virus | Common respiratory virus that causes cold-like illness in most people but is the leading cause of bronchiolitis and pneumonia in US infants and a major cause of… |
| RVP | Respiratory viral panel | Multiplex PCR test, usually on a nasopharyngeal swab, that detects many respiratory viruses and some bacteria at once, such as influenza, RSV, SARS-CoV-2, rhinovirus… |
| RZV | Recombinant zoster vaccine | Non-live shingles vaccine (Shingrix) given as two doses two to six months apart to adults 50 and older and to immunocompromised adults 19 and older. |
| S. aureus | Staphylococcus aureus | Bacterium carried in the nose or on the skin of about a third of people that causes boils, cellulitis, abscesses, pneumonia, bone infections, endocarditis and toxic… |
| SARS | Severe acute respiratory syndrome | Coronavirus disease that emerged in southern China in late 2002 and spread to about 29 countries in 2003, causing roughly 8,000 cases and 774 deaths before being… |
| SARS-CoV-2 | Severe acute respiratory syndrome coronavirus 2 | The coronavirus that causes COVID-19, first identified in Wuhan, China, in late 2019. |
| SSTI | Skin and soft tissue infection | Broad category covering infections of the skin and underlying tissues, from impetigo, cellulitis and erysipelas to abscesses, wound infections and necrotizing infections. |
| STD | Sexually transmitted disease | Traditional term for illnesses spread through sexual contact, still widely used by the public and in clinic names and insurance forms. |
| STEC | Shiga toxin-producing Escherichia coli | Group of E. coli strains, the best known being O157:H7, that produce Shiga toxins and cause bloody diarrhea, abdominal cramps and, in about 5–10 percent of cases… |
| STI | Sexually transmitted infection | Infection passed mainly through sexual contact, including chlamydia, gonorrhea, syphilis, trichomoniasis, HPV, herpes and HIV. |
| SVR | Sustained virologic response | Undetectable hepatitis C RNA at a set time after completing treatment, usually 12 weeks (SVR12), which is considered a virologic cure. |
| TB | Tuberculosis | Infectious disease caused by Mycobacterium tuberculosis that spreads through the air and usually affects the lungs, causing chronic cough, fever, night sweats and… |
| Td | Tetanus and diphtheria toxoids vaccine | Adult booster vaccine against tetanus and diphtheria recommended every 10 years after the childhood series, and sooner for dirty or major wounds if more than five years… |
| Tdap | Tetanus, diphtheria and acellular pertussis vaccine | Booster vaccine for adolescents and adults that protects against tetanus, diphtheria and whooping cough. |
| TSS | Toxic shock syndrome | Rapidly progressive, life-threatening illness caused by toxins from Staphylococcus aureus or group A Streptococcus that act as superantigens. |
| U=U | Undetectable equals untransmittable | Public health message, backed by large studies, that a person with HIV who keeps an undetectable viral load on treatment does not transmit the virus sexually. |
| VAERS | Vaccine Adverse Event Reporting System | US national early-warning system, co-managed by the CDC and FDA since 1990, that collects reports of health problems occurring after vaccination. |
| VL | Viral load | Amount of virus in the blood, measured by PCR as copies per milliliter, used to monitor HIV, hepatitis B and C, and CMV infection. |
| VRE | Vancomycin-resistant Enterococcus | Enterococci, usually Enterococcus faecium, that have acquired resistance to vancomycin. |
| VZV | Varicella-zoster virus | Herpesvirus that causes chickenpox (varicella) on first infection and later, after lying dormant in nerve ganglia, can reactivate as shingles (herpes zoster). |
| WNV | West Nile virus | Mosquito-borne flavivirus, spread mainly by Culex mosquitoes that feed on infected birds, and the leading cause of mosquito-borne disease in the continental US. |
More medical abbreviations
- Anatomy Abbreviations (70)
- Anesthesia Abbreviations (34)
- Cardiology Abbreviations (229)
- Dermatology Abbreviations (52)
- Drug Abbreviations (170)
- Drug Class Abbreviations (113)
- Emergency Medicine Abbreviations (97)
- Endocrinology & Diabetes Abbreviations (64)
- Gastroenterology Abbreviations (85)
- Health Insurance Abbreviations (107)
- Healthcare Credential Abbreviations (122)
- Hematology and Oncology Abbreviations (144)
- Hospital Abbreviations (89)
- Laboratory Test Abbreviations (135)
- Medical Documentation Abbreviations (79)
- Medical Imaging Abbreviations (58)
- Medical Research Abbreviations (94)
- Medical Specialty Abbreviations (47)
- Medication Route Abbreviations (41)
- Mental Health & Psychiatry Abbreviations (100)
- Musculoskeletal & Rheumatology Abbreviations (71)
- Nephrology & Urology Abbreviations (71)
- Neurology Abbreviations (131)
- Nursing Abbreviations (90)
- Obstetrics & Gynecology Abbreviations (89)
- Ophthalmology & ENT Abbreviations (74)
- Patient Assessment Abbreviations (65)
- Pediatric & Neonatal Abbreviations (51)
- Pharmacology Abbreviations (36)
- Pharmacy Abbreviations (134)
- Prescription Abbreviations (77)
- Rehabilitation Abbreviations (98)
- Respiratory Abbreviations (109)
- Surgical Abbreviations (51)