Carbapenem-Resistant Acinetobacter baumannii
Acinetobacter baumannii is a type of bacteria commonly found in the environment, including in soil and water. While generally harmless in the environment, Acinetobacter baumannii is a key cause of healthcare-associated infections, particularly in individuals who are immune-compromised. This is in part because many Acinetobacter baumannii bacteria are resistant to a group of antibiotics called carbapenems. Carbapenems are considered the last line of defense to treat multidrug-resistant bacterial infections, so infections caused by carbapenem-resistant Acinetobacter baumanii (CRAB) bacteria can be very difficult to treat. CRAB can cause pneumonia, as well as wound, bloodstream, and urinary tract infections.
Carbapenemase-producing CRAB (CP-CRAB) can pass on resistance to carbapenem antibiotics to other bacteria and can lead to widespread antibiotic resistance.
It can be difficult to eliminate CRAB once it is found in a health care facility, since the organism can live on skin and may survive in the environment for months.
Healthy people do not usually get sick from CRAB. People with longer hospital or long-term care facility stays, open wounds, tracheostomies, or invasive devices like ventilators or urinary catheters are at risk for infection with CRAB. Individuals with weakened immune systems, chronic lung disease, or diabetes are also at risk for infection.
CRAB can be spread person-to-person in health care settings through direct contact with patients or residents who are colonized or infected with CRAB, or via health care workers’ hands following care of those people. It can also be spread via contaminated surfaces in the patient’s or resident’s environment.
Symptoms of CRAB infection will depend on which part of the body is affected. CRAB can cause many different types of infections, such as bloodstream, wound, urinary tract, and lung infections.
Because there is such a wide range of symptoms, a laboratory test is needed to see whether a patient has CRAB.
The most commonly prescribed antibiotics are not effective against CRAB infections. Treatment decisions should be made on a case-by-case basis by a health care provider.
People who are colonized with CRAB who do not show active signs of infection do not need to be treated or decolonized.
Carbapenemase-producing CRAB (CP-CRAB) became a reportable communicable disease condition in Wisconsin in July 2022. Data on CP-CRAB cases prior to that time are based on voluntary reporting of isolates by clinical laboratories to the Wisconsin State Laboratory of Hygiene (WLSH).
Reported CP-CRAB cases by Wisconsin public health region, 2023
| Region | Cases |
|---|---|
| Southeastern | 75 |
| Northeastern | 37 |
| Northern | 1 |
| Western | 4 |
| Southern | 34 |
| Non-Wisconsin | 2 |
| Total Cases | 153 |
Data source: WSLH
Understanding our data: What does this chart mean?
- As of 2023, CP-CRAB cases have been detected in every Wisconsin public health region. Many of these cases are colonization cases discovered after investigation by public health.
- About 43% of CP-CRAB cases were first detected on a colonization screen, rather than clinical isolate.
- In Wisconsin, CP-CRAB cases have affected both acute care and post-acute care, including long-term care facilities.
- In 2023, 2 cases were detected in non-Wisconsin residents receiving care in Wisconsin.
- Of the carbapenemase genes unique to CRAB, OXA-24/40-like genes are most prevalent in Wisconsin.
About our data: How do we measure this?
- Case counts include both clinical and colonization screening isolates.
- CP-CRAB cases are detected through testing at WSLH, which performs a PCR test for carbapenemase genes that are unique to CRAB including OXA-23-like, OXA-24/40-like, and OXA-58-like genes.
For data on other multidrug-resistant organisms, visit the DHS MDRO webpage.
Resources
- Carbapenem-Resistant Acinetobacter baumannii, P-03232b (PDF): Fact Sheet for Health Care Settings: Educational fact sheet for the general public on CRAB in health care settings
- About Acinetobacter: CDC (Centers for Disease Control and Prevention) webpage, including information on symptoms, diagnosis, treatment, and prevention
As of July 1, 2022, carbapenemase-producing carbapenem-resistant Acinetobacter baumannii (CP-CRAB) is a Category II reportable communicable disease condition in Wisconsin. See the Reportable Multidrug-Resistant Organism webpage for additional information about communicable disease reporting for this organism.
Wisconsin Department of Health Services resources
- Reportable Multidrug-Resistant Organisms webpage
- Carbapenem-Resistant Acinetobacter baumannii, P-03232b (PDF): Fact sheet for health care settings.
CDC resources
Questions about carbapenem-resistant Acinetobacter baumanii? Contact us!
Healthcare-Associated Infections Prevention Program webpage | Phone: 608-267-7711 | Fax: 608-266-0049