CDC warns about high bacterial levels in dental waterlines

USA: The U.S. Centers for Disease Control and Prevention (CDC) reported high levels of waterborne bacteria in dental waterlines that have led to outbreaks of infection in children at certain dental offices.

The warning was sounded after bacterial infections were reported among children who visited paediatric dental clinics. The most recent suspected outbreak occurred in March, but there were two other confirmed outbreaks in 2015 and 2016.

Contaminated plumbing systems in dental offices

According to a health advisory issued by the federal agency, the waterborne bacteria Nontuberculous Mycobacteria can build up in the plumbing systems of dental offices.

Non-tuberculous Mycobacteria, or NTM, primarily causes serious lung infections, but it can also cause infections in other organs including the skin, blood and bones, according to the Cleveland Clinic.

“This type of bacteria is found naturally in soil, dust and water, and can contaminate water systems. Dental plumbing systems are particularly vulnerable to NMT because of the “long, small-diameter tubing and low flow rates used in dentistry and the frequent periods of stagnation,” the CDC said in the health advisory.

Microbial counts in dental waterline higher than recommended levels

The outbreak of suspected infections in March occurred among patients of the same pediatric dental facility.

The CDC hasn’t released any other information about the facility, but testing showed that microbial counts in the dental waterline at the facility were higher than recommended levels. The investigation is ongoing.

History of similar outbreaks in paediatric dental clinics

A similar outbreak that occurred in 2016 was linked to a paediatric dental clinic in Orange County, California where 71 patients became infected after pulpotomy procedures, which treat decaying baby teeth. In 2015, 24 children were infected after receiving dental care from a Georgia clinic.

In both outbreaks, the children, who were between the ages of 4 and 8, had developed severe infections which in certain cases required hospitalization or surgery. The CDC said that some of the children suffered “permanent tooth loss, hearing loss, facial nerve palsy and incision fibrosis.”

CDC recommendations to dental clinics

Dental waterlines are also known to be breeding grounds for dangerous bacteria such as Legionella, which causes a serious type of pneumonia called Legionnaires’ disease.

To protect their patients, the federal agency said that the dental clinics need to treat their waterlines with disinfectants regularly. In addition, they need to monitor water quality to make sure it meets the safety standards set forth by the Environmental Protection Agency (EPA).

The CDC recommends that dental providers consult their dental equipment manufacturer for the proper ways to maintain and monitor the quality of their water, and to train all staff on these methods.