Outbreak of piercing infections in Australia traced to contaminated aftercare solution

In a recent study published in the journal Emerging Infectious Diseases, a group of researchers investigated and controlled the outbreak of Pseudomonas aeruginosa (P. aeruginosa) infections linked to a specific batch of piercing aftercare solutions in New South Wales (NSW), Australia, using genomic sequencing and reviewing associated manufacturing standards.

Study: Community Outbreak of Pseudomonas aeruginosa Infections Associated with Contaminated Piercing Aftercare Solution, Australia, 2021. Image Credit: Daiana Campos / Shutterstock

Background 

Nonmedical body piercings, like ear piercings, often lead to bacterial infections, with 10%-30% of new sites developing infections. Bacteria such as Staphylococcus aureus (S. aureus), Streptococcus pyogenes, and especially P. aeruginosa are typical culprits. Thriving in wet environments, the latter is a frequent cause of piercing-related infections, which can vary from mild skin problems to severe complications necessitating surgery, often linked to factors such as swimming pool exposure, inadequate antisepsis, poor hand hygiene, and contaminated solutions.

In April 2021, three patients in Sydney reported P. aeruginosa infections following ear piercings from the same newly opened salon. More research is required to understand and prevent piercing-related P. aeruginosa outbreaks, thus ensuring safer piercing practices and product standards.

About the study

In the present study, researchers adopted comprehensive case definitions to enhance the accuracy of active case identification. A confirmed case was identified as someone who had a P. aeruginosa infection after a recent ear piercing. Meanwhile, probable cases involved those who, despite not having cultures taken or showing no growth, either visited the suspected facility or used the same aftercare product.

Through the NSW Public Health Rapid Emergency, Disease, and Syndromic Surveillance System (PHREDSS), they monitored patients at most public hospitals and identified potential infection cases by analyzing patient codes and conducting keyword searches.

Further investigations delved into the procedures performed on the confirmed patients, the aftercare products they utilized, and any complaints or notifications. Using the aforementioned surveillance system, more piercing-related infection cases were found in several regions, including Sydney, Wollongong, and Newcastle.

From April 30, 2021, weekly updates on emergency department visits related to piercing infections were shared with other public health units across NSW. These units reviewed patient records, gathered demographic data, and noted piercing and aftercare product details, while other states were informed of the NSW outbreak to identify potential cases.

Samples from the environment, aftercare solutions, and patients were collected and analyzed for bacterial identification, with positive results undergoing whole-genome sequencing. The entire study was executed as a public health initiative in accordance with the NSW Public Health Act 2010, obviating the need for ethics approval.

Study results 

The researchers reported that a sudden upsurge of piercing-related infections in New South Wales, Australia, was noticed in April 2021. The first facility under suspicion was a branch of a national chain of piercing salons, which had commenced its operations on April 1, 2021, by offering piercings at half-price. This salon, like the rest in its franchise, relied on an aftercare product called Protat. Consisting of natural preservatives like aloe vera, seed extract,  grapefruit, and Melaleuca alternifolia leaf oil, the solution also contains saline with benzalkonium chloride, an antimicrobial agent. Usually, after each piercing procedure, Protat was applied, and the same bottle was handed over to the client for further care.

As infections proliferated, data drawn from the PHREDSS indicated a stark increase in infections associated with piercings. A meticulous review identified 251 individuals with piercing-related infections, of which 62 tested positive for P. aeruginosa.

Probing further, samples were collected from 15 opened Protat bottles obtained from infected individuals. Shockingly, nine out of ten bottles from a specific batch were found contaminated with P. aeruginosa. The contaminated batch was dated to be used by October 1, 2023, and had been dispatched to multiple piercing shops between February and May 2021. Additionally, samples from 11 unopened Protat bottles were also retrieved, and of these, three tested positive for the same bacteria.

When diving deeper into the bacterial strains, researchers employed whole-genome sequencing. This disclosed that the majority of the isolates were of a rare type called ST988, which had not been seen before in local collections. Of the patients with this specific strain of the infection, most had availed services from the implicated salon or other branches in the same franchise. Further investigations revealed that even the one who claimed to have used a different batch was likely exposed to the contaminated batch at the store.

In response to the outbreak, NSW Health alerted clinicians, and the manufacturer of Protat voluntarily recalled the suspected batch. On understanding the gravity of the situation, the Australian Competition and Consumer Commission also published a recall notice for the batch, informing it had not only been distributed across various Australian states but also New Zealand.

The manufacturer undertook a review to identify the possible contamination sources. Several lapses in the manufacturing process were pinpointed, including potential compromises in raw material handling and inadequate cleaning of equipment. To combat future risks, the manufacturer decided to increase microbial testing, enhance the cleaning procedures, and possibly reformulate the product. By mid-June 2021, thanks to these corrective measures, the number of infections began to reduce, signaling a positive outcome of the collective efforts.

Conclusions

To summarize, in 2021, a NSW outbreak linked a P. aeruginosa piercing infection to a specific aftercare solution batch using whole-genome sequencing. Earlier outbreaks in England (2016) and Oregon, USA (2004) utilized molecular methods to trace contamination sources. Quick NSW outbreak identification was due to an observant clinician. Repeated global outbreaks emphasize the need for enhanced manufacturing standards for aftercare products, with the NSW incident underscoring the importance of rigorous production quality control, contamination detection, quality assurance, and effective testing.