Incidence of human papillomavirus contamination of transvaginal probes in Japan and possible contamination prevention strategy

Endocavity Ultrasound Transducers: Why High-Level Disinfection Is Necessary

As a medical imaging modality, ultrasound is used by a wide cross-section of practitioners including radiologists, obstetricians, gynecologists, gastroenterologists, urologists and cardiologists. The increasing popularity of ultrasound as a diagnostic tool is due not only to the ease of use and portability of systems, but also to the perceived safety aspect of the examination. This latter point needs to be examined. As with any reusable medical device, the ultrasound transducer, also known as a probe, could potentially be a vector for the transmission of pathogenic viruses and fungi between patients if not correctly disinfected after each use. This transmission risk is magnified for an endocavity transducer that has come in contact with the vagina, anal canal or oral cavity, as it could be contaminated with organisms transmitted by blood or mucosal, genital or rectal secretions. Based on the Spaulding system, transducers that come in contact with mucous membranes are classified as semi-critical devices that require high-level disinfection (HLD) after each patient procedure. This HLD process should eliminate all microorganisms except high numbers of bacterial endospores. Only a small number of countries worldwide have implemented transducer reprocessing guidelines that adhere to the Spaulding classification and recommend HLD for endocavity transducers. Overall, there is a lack of conformity among global health agencies regarding the use of HLD for endocavity transducers. This is primarily due to the perception that the infection transmission risk is negligible and that if an endocavity transducer has been covered with a single-use sheath for the procedure, then low-level disinfection provides sufficient protection against pathogen transmission. The objective of this study was to review the published risk of infection transmission from endocavity transducers. By highlighting the outbreaks and case reports that implicate pathogen transmission from transducers, we posit that HLD should be a global standard of practice for the reprocessing of endocavity transducers. It requires substantial time for national health administrations to develop and legislate new recommendations, and for practice changes to be accepted and implemented by healthcare providers. We recommend that Joint Commission International (JCI) and other equivalent organizations enforce the use of HLD of endocavity ultrasound transducers during their accreditation reviews.

Trends in Co-circulation of Oncogenic HPV Genotypes in Single and Multiple Infections among Unvaccinated Community

Cocirculation of multiple human papillomavirus (HPV) infections with low, probably high, and high‐risk genotypes are to be associated with various grades of infections and cancer progression. The oncogenic high‐risk HPVs are distributed and cocirculated throughout the world. This study was investigated to identify HPV genotypes related to genital disorders in unvaccinated women. The subjects were referred from clinics to a molecular lab for HPV testing in Iran as a low‐coverage vaccinated country. HPVs DNAs of cervical scrapping and genital tissue specimens of 1,133 un‐vaccinated women were genotyped using an in vitro diagnostic line probe (reverse hybridization) assay. In addition, phylogenetic trees were constructed on 100 MY09/MY11 polymerase chain reaction (PCR) amplicons of common genotypes of HPV L1 gene by Sanger sequencing. The mean age of the population study was 32.7 ± 8.0 and the mean age of HPV‐positive cases was 31.6 ± 7.8. HPV DNA was detected in 57.8% (655/1133) of women subjects and 42.2% (478/1133) of cases were undetected. Among 655 HPV‐positive cases, 639 subjects (56.4%) were related to defined genotypes and 16 subjects (1.4%) were untypeable. The highest prevalence rate of HPV genotypes was identified in the 25–34 years. The top 6 dominant HPVs in single and multiple genotypes were HPV6 (284/655 [43.4%]), HPV16 (111/655 [16.9%]), HPV31 (72/655 [11%]), HPV53 (67/655 [10.2%]), HPV11 (62/655 [9.5%]), and HPV52 (62/655 [9.5%]). Moreover, single, multiple and untypeable HPV genotypes were diagnosed as follows: 1 type (318/655 [48.5%]), 2 types (162/655 [24.8%]), 3 types (83/655 [12.7%]), 4 types (42/655 [6.5%]), more than 5 types (34/655 [5.3%]), and 1.4% un‐typeable subjects. The sequenced partial L1 gene of HPV genotypes (GenBank databases under the accession numbers: MH253467‐MH253566) confirmed and determined the cocirculated HPV genotypes' origins and addressed helpful insights into the future viral epidemiology investigations. Multiple HPV infections and cocirculation of various oncogenic HPV genotypes among the normal population (women and men) with asymptomatic forms are still challenging in unvaccinated communities. The preventive and organized surveillance programs for HPV screening are needed to be considered and compiled by health policy makers of low or unvaccinated countries.

Infection Transmission Associated With Contaminated Ultrasound Probes: A Systematic Review

A systematic review of seven studies on infections related to contaminated ultrasound probes showed that the infections were related to a failure in the decontamination process of ultrasound devices used on immature skin of neonates in an intensive care unit and transesophageal echocardiography probes. Six of the studies involved outbreaks in patients who underwent transesophageal echocardiography either during or after surgery or as a part of treatment for a nonsurgical cardiac condition. The evidence shows links between the infection outbreaks and environmental contamination, lack of standardized ultrasound probe disinfection processes, inadequate storage, and lack of monitoring of probe integrity. When personnel addressed the deficiencies (eg, improving the disinfection process, cleaning the probes immediately after use, inspecting the probes for defects), the infections ceased. Personnel involved with the reprocessing of ultrasound probes should clean, disinfect, inspect, and store ultrasound probes in a manner that maintains device integrity and prevents contamination.

Transvaginal ultrasound probes are human papillomavirus-free following low-level disinfection: cross-sectional multicenter survey

OBJECTIVES

To assess the frequency of detection of high-risk human papillomavirus (hrHPV) on transvaginal ultrasound (TVS) probes and keyboards and evaluate operator compliance with national recommendations for prevention of cross-infection during TVS.

METHODS

This was a multicenter observational survey involving 46 public and private centers, in the Paris region of France, in which at least five consecutive TVS examinations were performed per day. We audited 676 TVS procedures. We recorded preventive hygiene actions undertaken by the operator at three stages: (1) during TVS; (2) during probe disinfection; and (3) during preparation of the probe for the next TVS. After probe disinfection, we collected one sample from the bare probe and one from the ultrasound keyboard; following probe preparation for the next examination, an additional sample was obtained from the covered probe. The samples were tested for presence of hrHPV DNA using the Cobas® 4800 System.

RESULTS

We did not detect hrHPV DNA in samples collected from uncovered or covered probes (0%; 95% CI, 0.00-0.55%). Keyboard samples were positive for hrHPV in two cases (0.3%; 95% CI, 0.04-1.07%). During TVS, the operator avoided touching the keyboard with a hand that had touched the patient's vulva in 86% of cases and held the probe with a gloved hand in 68%. Before probe disinfection, the operator wore new gloves, or performed hand disinfection in 8% of cases. The probe disinfection technique used was adequate in 87% of cases, not performed at all in 12% and insufficient in 1%. Before preparing the probe for the next scan, the operators disinfected their hands or used new gloves in 81% of cases. The probe cover and the coupling gel used complied with recommendations in 98% and 46% of cases, respectively. Of the seven preventive hygiene actions recommended in national guidelines, all were performed in 2%, three to six in 95% and two in 3% of observations. In four (9%) centers, disinfection was not performed in over half the observations.

CONCLUSIONS

No evidence of hrHPV DNA was found on TVS probes and probe covers following low-level disinfection, despite suboptimal compliance with hygiene guidelines. Routine TVS practice could be made easier and safer with a global approach to probe disinfection and hand hygiene. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Risk of infection following semi-invasive ultrasound procedures in Scotland, 2010 to 2016: A retrospective cohort study using linked national datasets

INTRODUCTION

Outbreak reports indicate a risk of cross-infection following medical procedures using semi-invasive ultrasound probes. This study aimed to evaluate the risk of infection, using microbiological reports and antibiotic prescriptions as proxy measures, associated with semi-invasive ultrasound probe procedures, including transoesophageal echocardiography, transvaginal and transrectal ultrasound.

METHODS

Patient records from the Electronic Communication of Surveillance in Scotland and the Prescribing Information System were linked with the Scottish Morbidity Records for cases in Scotland between 2010 and 2016. Three retrospective cohorts were created to include inpatients/day-cases and outpatients in the following specialties: Cardiology, Gynaecology and Urology. Cox regression was used to quantify the association between semi-invasive ultrasound probe procedures and the risk of positive microbiological reports and community antibiotic prescriptions in the 30-day period following the procedure.

RESULTS

There was a greater hazard ratio of microbiological reports for patients who had undergone transoesophageal echocardiography (HR: 4.92; 95% CI: 3.17-7.63), transvaginal (HR: 1.41; 95% CI: 1.21-1.64) and transrectal ultrasound (HR: 3.40; 95% CI: 2.90-3.99), compared with unexposed cohort members after adjustment for age, co-morbidities, previous hospital admissions and past care home residence. Similarly, there was a greater hazard ratio of antibiotic prescribing for those who had received transvaginal (HR: 1.26; 95% CI: 1.20-1.32) and transrectal (HR: 1.75; 95% CI: 1.66-1.84) ultrasound, compared with unexposed patients.

CONCLUSION

Analysis of linked national datasets demonstrated a greater risk of infection within 30 days of undergoing semi-invasive ultrasound probe procedures, using microbiological reports and antibiotic prescriptions as proxy measures of infection.