The CDC's MMWR Morb Mortal Wkly Rep reported that between 2021 and 2022, 23 cases of infections caused by Burkholderia multivorans (sequence type ST659) were reported at two hospitals in Southern California, attributed to contaminated ice and water from these machines. To manage the outbreak, public health officials advised stopping the use of ice and tap water during clinical care activities, and an investigation is underway to identify potential sources of contamination in the ice machines.1 B multivorans is a gram-negative bacillus and part of the Burkholderia cepacia complex, known for causing opportunistic infections primarily in patients with cystic fibrosis, chronic granulomatous disease, and those who are immunocompromised. While central nervous system infections are rare, management is complicated by the bacterium's resistance to many antimicrobial agents.2
In addition to the 23 cases reported in Southern California, this study identifies 23 previously unreported infections of B multivorans ST659 occurred between 2020 and 2024. This includes 13 cases at a Northern California hospital, eight at a hospital in Colorado, and two more cases at one of the Southern California hospitals. All four hospitals used the same brand of ice machines, as well as similar filters, descaling, and sanitizing products. B multivorans was isolated from samples collected from ice machines in two of these hospitals.1
Main Takeaways
- Between 2021 and 2022, 23 cases of B multivorans infections were linked to contaminated ice and water from machines in two Southern California hospitals, leading to a recommendation to cease their use in clinical care.
- The study also identified 23 previously unreported infections of B multivorans ST659 across four hospitals, underscoring the broader issue of contamination in ice machines.
- Whole genome sequencing indicated that the clinical and environmental isolates of B multivorans were highly genetically similar, suggesting a common source of contamination in the ice machines.
Hospital Case Reports
- Hospital A: Identified 13 cases of B multivorans ST659 between September 2020 and October 2021, with most patients having respiratory specimens as the source of infection.
- Hospital B: Reported 20 cases from August 2021 to July 2022, plus two additional cases from September 2022 to February 2023, with contamination found in ice and water samples from ice machines.
- Hospital C: Documented three cases between August 2021 and July 2022, but no B multivorans was isolated from ice machines, although one sample showed high bacterial levels.
- Hospital D: Identified eight cases from April 2023 to February 2024, with B multivorans found in six of the 10 sampled ice machines during environmental testing.
According to the investigators, “The higher proportion of intra-abdominal specimens with B multivorans at hospital D is consistent with the observed practice at this hospital of directly applying refillable ice bags to abdominal surgical wounds and device insertion sites. High bacterial counts, such as that found in water samples from an ice machine at Hospital C, might also indicate risk of transmission of water-associated bacteria to patients.”1
Whole genome sequencing was performed to evaluate the genetic similarity of the isolates. The analysis showed that all clinical and ice machine isolates were highly similar, with only 0 to 14 single nucleotide variant differences across 81% of the selected reference genome.
This report has two key limitations, the descaling and sanitizing products tested may not have been from the same lots used during patient exposures. Second, patient medical records do not document specific exposures to tap water and ice, making it difficult to confirm when and how these exposures occurred.
The findings indicate that during outbreaks of water-related organisms in healthcare facilities, staff should refrain from using tap water, including ice and water from ice machines, for patient care.
Reference
Vazquez Deida AA, Spicer KB, McNamara KX, et al. Burkholderia multivorans Infections Associated with Use of Ice and Water from Ice Machines for Patient Care Activities ― Four Hospitals, California and Colorado, 2020–2024. MMWR Morb Mortal Wkly Rep 2024;73:883–887. DOI: http://dx.doi.org/10.15585/mmwr.mm7339a4
Peralta DP, Chang AY, Ariza-Hutchinson A, Ho CA. Burkholderia multivorans: A rare yet emerging cause of bacterial meningitis. IDCases. 2018;11:61-63. Published 2018 Jan 9. Accessed October 9, 2024. doi:10.1016/j.idcr.2018.01.002
