Blood borne virus testing of 2250 patients in an unusual, repeated dental patient notification exercise: challenges faced and lessons learnt.

OBJECTIVES: The objectives of this study were to ascertain the risk created for patients of two dental practices where infection control was found to be inadequate, and if the risk was deemed to be significant, initiate an investigation involving notification and blood borne virus (BBV) testing to establish if any patient-to-patient BBV transmissions had occurred as a result of these infection control breaches.

STUDY DESIGN: A case study.

METHODS: A public health investigation and patient notification. Investigations involved practice inspections, staff interviews and examination of invoices. The practices were not fully cooperative during the investigation and provided misleading information regarding the allegations. This led to two patient notification exercises, as more serious breaches were uncovered following the first notification exercise. Risk assessments of BBV transmission likelihood were undertaken and informed the nature of the advice given to patients.

RESULTS: The health board wrote to 5100 patients informing them of the situation. BBV testing was offered in the second notification exercise and 2250 patients opted to be tested for HIV, hepatitis B and hepatitis C. There were no new cases of HIV or hepatitis B but less than five patients were found to be positive for hepatitis C. None of these cases were proven to have contracted their infection as a result of the dental infection control lapses.

CONCLUSIONS: This incident was unusual in that the practice was found to be repeatedly and knowingly putting patients at risk, and attempts were made to cover up breaches during the investigation. In future, health boards would benefit from a risk assessment tool to aid decision making regarding notification exercises, and whether testing is indicated where risk to patients is low. This would help ensure that notification exercises do more good than harm.