Impure water: California searches for solutions to disease outbreak among pediatric dental patients

March 14, 2017
Noel Kelsch, RDHAP discusses how California authorities diligently searched for solutions for disease outbreak among pediatric dental patients.

By Noel Kelsch, RDH, RDHAP, MS

The health-care provider who sat across from me was sincere, concerned, and passionate about his role in keeping consumers safe. He was not going to dismiss any risk-high, medium or low. It was clear that he had the consumers' health and welfare as his highest priority. I listened intently as the story unfolded. He openly shared what was known, as well as what was not known. I was impressed with his candor, and his aim of informing and empowering people to make changes to keep the public safe.

Dr. Eric Handler, public health officer for the Orange County (Calif.) Health Department is not just a health-care professional, he is an advocate for awareness and necessary changes in infection control practices.

Many of you have read the national news about the infection control issues involving water in a Georgia office (if not, see my Sept. 2016 column at or have heard about the pediatric office in Orange County (OC) that required 67 children to be hospitalized (see Table 1). You might be wondering if there are requirements for treatment of water in dental facilities. This pediatric dental clinic was in compliance with infection control guidelines and regulations; however, there are no regulations requiring water treatment for use in dental clinic procedures. Best practices reinforce the need for water monitoring and treatment.

What happened?

In early September 2016, the Orange County Health Care Agency (OCHCA) was notified of several cases of bacterial infections called Mycrobacterium abscessus being seen at Children's Hospital of Orange County. The common thread for all of these children was they had all been treated at the same dental clinic. These children all have the same type of bacterial infection.

This is a very serious disease that often results in a loss of bone, permanent teeth, and disfigurements. This severe, invasive disease often requires very complicated antibiotics that have intensive side effects and invasive treatment that can last for months. The incubation period can last up to nine months.

OCHCA soon established that all of the children who had the disease had undergone the same dental procedure, a pulpotomy. Dental health-care professionals know that this procedure is sometimes performed in very deep cavities on deciduous teeth to preserve them, so that the permanent tooth has the necessary elements to erupt properly.

The likely source of this outbreak was the office's dental water system, and the patients were susceptible host because they had current infections and, thus, the pulpotomy was necessary.

The office was reported to be in compliance with infection control procedures. When the water from the dental units were tested, however, Mycrobacterium abscessus was found in the system at an unsafe level. The OCHCA consulted with the Centers for Disease Control and Prevention (CDC), and it was determined that it was necessary to legally place an order to prohibit the clinic from using an onsite water system for dental procedures until specific criteria were met to ensure that water supply in the clinic was free from mycobacterium contaminant.

The owner of the clinic was very cooperative and clearly had the patients' interest at heart. He replaced the entire water system in the clinic going beyond what was required.

Unfortunately, On Dec. 15, 2016, OCHCA's public health laboratory identified Mycobacteria mucogenicum growing from multiple water samples obtained as part of follow-up testing at the facility. This was after the water system had been replaced. Though M. mucogenicum is not known to pose the same risk to dental patients as M. abscessus, the identification of any mycobacterium (even at low levels) was of sufficient concern that the health officer issued a second order requiring closure of the clinic pending further investigation of the situation.

Since this is a ground breaking event, they had to work with the CDC and the Dental Board of California to determine what conditions were necessary to lift the order. This is not taken lightly in the state of California. Dr. Handler explained that California Health and Safety Code Sections 12030 and 120175 and California code of Regulations, Title 17, Section 2501, requires that County Health Officer or designee(s) to take whatever steps deemed necessary for the investigation and control of infectious or communicable diseases.

As it states on the OCHCA website, the following conditions must be met to the satisfaction of the county health officer for the order to be lifted. These conditions include:

  • Clinic shall cooperate fully with the health officer order.
  • Clinic shall implement additional measures necessary to identify and remove any and all ongoing sources of bacteria posing or potentially posing a risk to the public, including patients.
  • Certification by the Dental Board of California that the clinic's practices meet the dental board's accepted standards of practice.
  • Certification by the CDC that there are no bacterial levels at the clinic that pose or potentially pose a risk to the public, including patients.
  • A health officer-approved independent expert, in addition to the CDC, would certify that there are no bacterial levels at the clinic that pose or potentially pose a risk to the public, including patients.

At the press deadline, there is no confirmed explanation on why Mycrobacterium is still present in the waterline. The CDC has stated that this is a low-risk situation at this point because of the low level of Mycrobacterium that was found in the water.

Dr Handler made a very profound statement: "The fact that it did not grow does not mean it is not there. We do not know how this happened or where the Mycrobacterium came from. There is a low-level risk. We cannot answer the questions surrounding this. That is why I am overly cautious."

The facility discontinued performing pulpotomy procedures from Sept. 6 through Nov. 7 in order to replace their internal water system and install appropriate infection control safeguards. At this time, the office is using a separate sterile water delivery system.

Opportunity for Change:

As cases are evaluated and the risks weighed, there is an opportunity for learning. This event could happen in any dental office. It gives us all the opportunity for change-an opportunity to understand the importance of water in the chain of infection in the dental setting. Dr. Handler shared, "My hope is that this incidence can enlighten everyone to the importance of water quality in the dental setting."

All dental offices should be reviewing the recommendations for quality water in the dental setting and assuring water safety by testing their water. RDH

Current status of the M. abscessus outbreak as of Jan. 10, 2017

67 children have been reported to have slowly progressive oral cellulitis consistent with M. abscessus infection following dental pulpotomy procedures at this facility. Additional potential cases are undergoing clinical assessment.

21 of the 67 cases have been identified by culture to have M. abscessus-type infection. Most of these 21 have been confirmed to have M. abscessus infection, with the rest awaiting final mycobacterial species identification.

Infections have now been identified in children who have received pulpotomies performed from March 1 to August 20, 2016.

Symptoms have begun a median of 65 days (range 15-255 days) after pulpotomy and progressed despite treatment with antibiotics such as Augmentin (amoxicillin/clavulanate), clindamycin, or amoxicillin. Due to the length of incubation period, additional cases may be identified.

M. abscessus infection should be considered in children who present with oral cellulitis and had a pulpotomy at the facility prior to March 1. In a similar previous outbreak of mycobacterial infection in a dental clinic, incubation periods lasted up to nine months.

Tips for ensuring water quality

  1. Test: Follow manufacturer's recommendations for monitoring the quality of the water to ensure that the recommended bacterial counts are being adhered to. All dental units should use systems that treat water to meet drinking water standards (i.e., ≤ 500 CFU/mL of heterotrophic water bacteria). You should be testing your quality of water on each dental unit and each point of water delivery.
  2. Treat: Independent reservoirs or water-bottle systems alone are not sufficient. Commercial products and devices are available that can improve the quality of water used in dental treatment. Consult with the dental unit manufacturer for appropriate water maintenance methods and recommendations for monitoring dental water quality.
  3. Sterile water for surgical procedures: During surgical procedures, you must take the next step of using an appropriate delivery device such as a bulb syringe or sterile tubing/single use devices that bypasses the dental unit waterline. Sterile water is required for surgical procedures in the dental setting.
  4. Discharge: Discharge water and air for a minimum of 20 to 30 seconds after each patient, from any device connected to the dental water system that enters the patient's mouth (for example, handpieces, ultrasonic scalers, and air/water syringes).
  5. Consult: Consult the dental unit's manufacturer for the need to periodically maintain anti-retraction devices.

Source: Kohn WG, Collins AS, Cleveland JL, Harte JA, Eklund KJ, Malvitz DM; Guidelines for infection control in dental health-care settings-2003. MMWR Recomm Rep 2003;52(No. RR-17).

Centers for Disease Control and Prevention. Summary of Infection Prevention Practices in Dental Settings: Basic Expectations for Safe Care. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Division of Oral Health; March 2016.

NOEL BRANDON KELSCH, RDH, RDHAP, MS, is a syndicated columnist, writer, speaker, and cartoonist. She serves on the editorial review committee for the Organization for Safety, Asepsis and Prevention newsletter and has received many national awards. Kelsch owns her dental hygiene practice that focuses on access to care for all and helps facilitate the Simi Valley Free Dental Clinic. She has devoted much of her 35 years in dentistry to educating people about the devastating effects of methamphetamines and drug use. She is a past president of the California Dental Hygienists' Association.