For a child bursting with energy, few things are more fun than hurtling through a bouncy castle, launching into the air, and ping-ponging between every surface. But that childhood buoyancy will quickly deflate when it turns out those surfaces are smeared with a hypervirulent, multidrug-resistant pathogen.
That was the horrifying reality for a community in Ireland in fall 2025. Neighbors had gathered for an afternoon of merriment, complete with a barbecue, a sweets station, and three bouncy castles. Officials estimate that about 120 people joined the festivities, and around half of them were children and teens. Within a day, some children began developing signs of an infection. In all, 48 children in the community developed aggressive skin and soft-tissue infections.
Of the 48 cases, 33 were treated by their regular doctor, and 15 sought emergency care. Four children ended up being hospitalized. Luckily, all of the children recovered. The results of the outbreak investigation were reported this week in the journal Eurosurveillance.
Party crashers
Local health officials became alerted to the outbreak nine days after the event, when a 12-year-old boy was hospitalized for a skin infection. His doctors had determined he was infected with MRSAâÂÂaka methicillin-resistant Staphylococcus aureus. By then, there were around 25 other, less severe cases identified.
Genomic sequencing revealed the outbreak was caused by a rare strain of MRSA capable of producing a cytotoxin called PantonâÂÂValentine leukocidin (PVL). This toxin can destroy immune cells and spark inflammation. ItâÂÂs often linked to necrotic lesions.
The bacteriumâÂÂs hostilities were clear in the outbreak; most of the infected children developed symptoms within four days of the event, much faster than the usual incubation period of 4âÂÂ10 days. Some saw their infections develop within hours. The infected children reported a range of skin and soft tissue symptoms, including spots, pustules, blisters, and abscesses. Most of the skin infections erupted on the childrenâÂÂs legs, particularly their thighs, fitting with an exposure in the bouncy castles. Twelve cases also reported systemic symptoms, such as fever, nausea, or vomiting.
The MRSA strain, called t016-ST22-MRSA-IV, has a unique pattern of antibiotic resistance; it could resist at least four drugs, including flucloxacillin, ciprofloxacin, gentamicin, and trimethoprim. Fortunately, there were others to which it was still susceptible, including clindamycin, tetracycline, fusidic acid, co-trimoxazole, and linezolid.
MRSA most often plagues healthcare settings, but itâÂÂs also known to spread in communities, such as in this case. So-called community-associated MRSA is often linked to crowded settings where people have close contact, such as sports activities, daycares, and prisons. The outbreak reported here was not only the largest MRSA outbreak ever recorded in Ireland, it was also the first known outbreak anywhere to be linked to bouncy castle use. The connection became more understandable during the official investigation.
Ideal conditions
After interviewing the families of the infected children, officials learned that most of the children played in the bouncy castles for multiple hoursâÂÂsome as long as five, six, or more hours. Inside, it was crowded, and the childrenâÂÂs play was described as âÂÂrough-and-tumbleâ (as parents would likely expect). Such play could have caused superficial abrasions and scrapes, offering the bacterium an opening. Parents also recalled that the weather that day was humid, warm, and rainy. Many of the children were noticeably wet. In all, these conditions could have been ideal for an MRSA strain to flourish and spread.
Of the 48 children infected, 47 played in the bouncy castles. The one child who had not been in the inflatable structure had very close contact with an exposed child shortly afterward. In all, officials concluded that no other exposure appeared as a plausible explanation for the outbreak; everything pointed to the bouncy castles. Still, they decided against trying to swab them for the MRSA strain. For one thing, a positive surface swab still wouldnâÂÂt confirm the castle was the source. Moreover, by the time officials had suspected the castles, they questioned whether MRSA would still be alive on surfaces, let alone how much of the surface of the three castles they would have to swab to find any. Instead, the health officials contacted the bouncy castle owners and advised them to do a thorough decontamination.
Based on all the data, they hypothesize that one or more of the children at the event went into the castles with an active infection, introducing a large load of bacterial contamination. This resulted in many children getting a high exposure to the hypervirulent pathogen, and they swiftly developed aggressive infections amid very favorable environmental conditions. Luckily, there was only one case of a secondary infectionâÂÂthe one child who was infected who did not go inside the castles. Officials speculated that prompt outbreak responses kept the MRSA strain from moving onward in families and the community.
In addition to treating infected children with antibiotics, officials advised the children and their family members to undergo a decolonization protocol. This involved using a chlorhexidine-based or equivalent antimicrobial body wash once a day for five days, along with a mupirocin nasal antimicrobial ointment, also for five days. The outbreak was declared over 40 days after the community event, after two standard incubation periods had passed without a new case.
Overall, the officials described the outbreak as âÂÂunusual and complexâ with a âÂÂnovel mechanismâ for spreading an alarming strain of MRSA. They urge owners of bouncy castles to be aware of this newly discovered risk and ensure adequate decontamination between events.

