Epidemiologic and Molecular Investigation of a MRSA Outbreak Caused by a Contaminated Bathtub for Carbon Dioxide Hydrotherapy and Review of the Literature

Table 2

Literature overview of MRSA outbreaks linked to hydrotherapy or other bathing activities.

Report	Persons affected and clinical characteristics	Setting	Role of hydrotherapy/bathing	Control measure regarding hydrotherapy/bathing
1 [19]	9 patients, 6 patients with soft tissue infections, one patient died.	Single-hospital outbreak	MRSA-positive environmental samples from the hydrotherapy department; discussed by the authors as an unclear (secondary) contributor to spread.	Enforcing cleaning in the hydrotherapy department
2 [20]	At least 4 patients, all with clinically relevant infections (bloodstream, respiratory and wound infection).	Single-hospital outbreak	MRSA-positive environmental samples from the hydrotherapy room on the burn unit; discussed by the authors as a potential contributor to spread.	Routine cleaning in the hydrotherapy room
3 [21]	82 mothers with MRSA from episiotomy wound/perineum (46), vaginal discharge (23), urinary tract (9), abdominal wound (2), and breast abscess (2).; 28 newborns, 8 newborns had a MRSA conjunctivitis, and the others were colonized.	Single-hospital outbreak	MRSA-positive environmental samples from baths and bidets on a postnatal ward; discussed by the authors as a relevant contributor to spread among other factors such as contaminated mattresses.	Cleaning and refurbishment of baths
4 [15]	37 mothers, 18 newborns, and 9 staff members. Clinically relevant infections occurred in 10 mothers (5 Caesarian section wound infections) and 2 newborns. Most mothers were nasal and perineal carriers of MRSA (23 and 28, respectively). Most newborns were nasal carriers (14) and had positive samples from the umbilicus (9). The staff members were colonized (nasal).	Single-hospital outbreak	MRSA-positive environmental samples from a bath and bidet on an antenatal and neonatal ward; discussed by the authors as a relevant contributor to spread among others.	Discontinuation of bath usage
5 [14]	4 patients with bloodstream infections, one patient died. 1 nurse was colonized (nasal sample).	Single-hospital outbreak	All patients used the same bathtub; environmental samples of the bathtub were not taken; bathtub discussed by the authors as the major contributor to spread.	Discontinuation of bath usage
6 [6]	12 patients. One patient had a skin graft infection. The other patients were colonized (mostly skin and soft tissue).	Multihospital outbreak	MRSA-positive environmental samples from hydrotherapy equipment (stretcher and shower hand held) on a plastic surgery/burn unit; discussed by the authors as the major contributor to spread.	Change of hydrotherapy procedure (no more use of stretchers)
7 [22]	10 football players with skin/soft tissue infections.	Players of a college football team	Usage of whirlpools was discussed by the authors as a potential contributor to spread due to limited water disinfection. However, direct contact during training sessions was presumed to be the most relevant transmission pathway among the players. Water and environmental samples were not taken.	Change of whirlpool practice (water change and disinfection after each usage)
8 [17]	5 football players with skin/soft tissue infections.	Players of a professional football team	Although MRSA was not found in environmental samples, the authors discussed that whirlpool usage might be a potential contributor to spread as methicillin-susceptible Staphylococcus aureus strains were found in water samples and in player samples.
9 [16]	6 neonates with skin/soft tissue infections.	Single-hospital outbreak	Although MRSA was not found in environmental samples, the authors discussed that the discontinuation of bathtub usage was relevant for outbreak control.	Discontinuation of bath usage and implementation of a chlorhexidine-based decolonization for patients

The role of hydrotherapy in each outbreak was categorized as follows: (i) unclear; (ii) potential; (iii) relevant; and (iv) major.