Health Care Outbreaks and Multidrug-Resistant Organisms

Health care settings are generally seen as safe spaces for patients and residents. However, outbreaks of communicable diseases in health care settings can arise and spread quickly, posing a threat to patient and resident safety.

Outbreaks in health care settings usually start with breakdowns in best practices designed to prevent disease transmission. Often, these outbreaks result from a failure to follow core infection prevention and control practices. Outbreaks can also result from exposure to contaminated medical products or reusable medical equipment.

An outbreak is defined as more disease occurring than what is usually expected:

  • Over a given time (e.g., within 2 weeks)
  • In a specific location (e.g., a specific unit in a health care facility)
  • For a target population (e.g., staff, long-term care residents)

In Montana, all confirmed or suspected outbreaks of communicable diseases in all types of health care facilities are reportable to local public health, as required by Montana Administrative Rule 37.114.203.

Table 1. Montana Health Care Facility Outbreaks of Communicable Diseases, 2024-2025

This table summarizes outbreaks of communicable diseases in health care settings for 2024 and 2025. This table will be updated on a yearly basis for the previous year. All data in this table was collected from health care facility outbreak investigations conducted by local and tribal public health and reported to MTDPHHS.
Disease 2024 Health Care Setting Outbreaks 2025 Health Care Setting Outbreaks
Acute Respiratory Illness 7 5
Candida auris 0 3
Carbapenemase-Producing Organism 8 6
COVID-19 312 90
ESBL E. coli 0 1
Group A Streptococcus 3 14
Influenza 28 31
Lice 1 0
Norovirus / Acute Gastrointestinal Illness 24 24
Respiratory Syncytial Virus (RSV) 7 6
Total 390 180

 

For more information on outbreaks in Montana, please visit Montana Outbreaks dashboard.

In Montana, select multidrug-resistant organisms (MDROs), including Candida auris, carbapenem-resistant organisms (CROs), carbapenemase-producing organisms (CPOs), vancomycin-intermediate Staphylococcus aureus (VISA), and vancomycin-resistant Staphylococcus aureus (VRSA), are reportable to local and tribal public health under Montana Administrative Rules 37.114.203 and 37.114.313. Outbreaks of other MDROs are also monitored, such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus.

Carbapenem-Resistant Organisms (CROs)

CROs are organisms resistant to the carbapenem antibiotic class. The most common CROs in the United States are Enterobacterales (CRE), Acinetobacter baumannii (CRAB), and Pseudomonas aeruginosa (CRPA).

Carbapenemase-Producing Organisms (CPOs)

CROs that produce carbapenemases, enzymes that break down the antibiotic class of carbapenems, are considered CPOs. The carbapenemase gene can be readily transferred between bacteria, leading to rapid resistance spread. These organisms can be spread within the health care setting through contaminated health care worker hands or through contaminated equipment. The first CPO case was identified in Montana in 2019.

Vancomycin-Resistant Organisms

Vancomycin is an antibiotic used to treat bacterial infections throughout the body and is frequently used for individuals with penicillin allergies. The most common vancomycin-resistant organisms within the United States are Enterococcus (VRE) and Staphylococcus aureus (VISA/VRSA). Staphylococcus aureus can also exhibit a range of resistance to vancomycin, with VRSA being the most resistant to vancomycin and VISA being intermediately resistant to vancomycin. VISA/VRSA infections are exceptionally rare in the United States.

Candida auris

Candida auris (C. auris) is a type of yeast that can cause severe illness and spreads easily among patients in health care facilities. It is often resistant to antifungal treatments, which means that the medications that are designed to kill the fungus and stop infections do not always work. The first case of C. auris was identified in Montana in 2025.

Montana currently focuses on containment response for MDROs.

MDRO Resources:

For Montana-specific MDRO data, please visit the MDRO dashboard.