Decontamination of Intravaginal Probes Infected by Human Papillomavirus (HPV) Using UV-C Decontamination System

Recommendations for the Cleaning of Endocavity Ultrasound Transducers Between Patients

The COVID-19 pandemic highlighted the importance of infection prevention and control measures for all medical procedures, including ultrasound examinations. As the use of ultrasound increases across more medical modalities, including point-of-care ultrasound, so does the risk of possible transmission from equipment to patients and patients to patients. This is particularly relevant for endocavity transducers, such as trans-vaginal, trans-rectal and trans-oesophageal, which could be contaminated with organisms from blood, mucosal, genital or rectal secretions. This article proports to update the WFUMB 2017 guidelines which focussed on the cleaning and disinfection of trans-vaginal ultrasound transducers between patients.

The use of ultraviolet light generated from light-emitting diodes for the disinfection of transvaginal ultrasound probes

Transvaginal ultrasound probes (TVUS) are used for several gynecological procedures. These need to be disinfected between patient use. In the current study we examine whether UVC delivered using light emitting diodes for 90 seconds can provide sufficient disinfection efficacy. A new UVC device that delivers UVC radiation at 265nm-275nm for 90 seconds was used. TVUS probes were swabbed before and after use in an in vitro fertilization clinic. Microbes on the swabs were cultured and identified. In addition, the ability of the UVC device to provided repeated high-level disinfection was analysed by deliberately contaminating probes with spores of Bacillus subtilis and then performing the UVC disinfection and bacterial culture. 50% of probes were contaminated with bacteria, most commonly Bacillus sp., directly after in vivo use. Whereas 97% were sterile after UVC disinfection for 90 seconds. The UVC treatment resulted in no growth of B. subtilis spores after each of five repeated contaminations with 5-9 x 107 spores on the probes. This study has found that UVC delivered via light emitting diodes for only 90 seconds can produce high level disinfection of transvaginal probes.

Time-effectiveness and convenience of transvaginal ultrasound probe disinfection using ultraviolet vs chlorine dioxide multistep wipe system: prospective survey study

OBJECTIVES

To compare the efficiency, ease of use and user satisfaction of two methods of transvaginal ultrasound probe high-level disinfection: ultraviolet-C radiation (UV-C) and a chlorine dioxide multistep wipe system.

METHODS

This was a prospective survey study. UV-C units were introduced into a busy early pregnancy assessment service and compared with a multiwipe system for disinfection. Before seeing each patient, healthcare professionals (HCPs) measured with a stopwatch the time taken to complete a cycle of disinfection using either UV-C or chlorine dioxide multistep wipes and responded to a quick-response (QR) code-linked survey. Additional essential tasks that could be completed before seeing the next patient during probe disinfection were also documented. Using another QR code-linked survey, data on ease of use, satisfaction with the system used and preferred system were collected. The ease of use and satisfaction with the system were rated on a 0 to 10 Likert scale (0 poor, 10 excellent). A free-text section for comments was then completed.

RESULTS

Disinfection using UV-C (n = 331) was 60% faster than the chlorine dioxide multiwipe system (n = 332) (101 vs 250 s; P < 0.0001). A greater number of tasks were completed during probe disinfection when using UV-C, saving a further 74 s per patient (P < 0.0001). The HCPs using UV-C (n = 71) reported greater ease of use (median Likert score, 10 vs 3; P < 0.0001) and satisfaction (median Likert score, 10 vs 2; P < 0.0001) compared with those using the multiwipe system (n = 43). HCPs reported that the chlorine dioxide system was time-consuming and environmentally unfriendly, while the UV-C system was efficient and easy to use. Overall, 98% of the HCPs preferred using the UV-C system.

CONCLUSIONS

UV-C technology is more time-efficient and allows more essential tasks to be completed during disinfection. For a 4-h ultrasound list of 15 patients, the use of UV-C would save 55 min 45 s. HCPs found UV-C preferable and easier to use. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Trend of HPV 16/18 Genotypes in Cervical Intraepithelial Neoplasia Grade 3: Data for 2007-2018

Aim

In the post-vaccination era, the starting age and time intervals of cervical screening could change (older age and longer screening intervals). This scenario may be achieved by significantly reducing human papillomavirus (HPV) 16/18 prevalence (genotypes included in the current vaccines). In this regard, assessing the trend over time of these HPV infections in high-grade cervical lesions can provide information on the objective. The present study aimed to evaluate the trend of HPV 16/18 over the years 2007–2018 in women with cervical intraepithelial neoplasia (CIN) grade 3.

Methods

This is a retrospective multi-institutional study including HPV genotyped and unvaccinated women under 30 with CIN3. The sample was divided into the following periods: 2007–2010, 2011–2014, 2015–2018. HPV genotypes were grouped in genotypes 16/18, genotypes 31/33/35/52/58/67 (genetically related to HPV16), genotypes 39/45/59/68/70 (genetically related to HPV18), genotypes 31/33/45/52/58 (high-risk types included in the nonavalent vaccine), possibly carcinogenic HPV (genotypes 26/30/53/67/70/73/82/85), low-risk HPV (genotypes 6/11/40/42/43/44/54/55/61). The trend between periods and HPV genotypes was measured using the Cochran–Armitage test for trend.

Results

The final analysis included 474 participants. HPV 16/18 prevalence decreased significantly over the years (77.8% vs 68.9% vs 66.0%, respectively, Ptrend=0.027). Possibly carcinogenic HPV (genotypes 26/30/53/67/70/73/82/85) showed a significant negative prevalence trend over time (4.9% vs 1.1% vs 1.3%, respectively, Ptrend=0.046). Finally, there was a significant positive trend over the years for high-risk HPV genotypes 31/33/45/52/58 in women under 25 (9.9% vs 17.0% vs 24.0%, respectively, Ptrend=0.048).

Conclusion

The prevalence of CIN3 lesions related to HPV 16/18 genotypes decreased over time from 2007 to 2018. These data highlight a herd effect of the HPV vaccine. However, fifteen years after HPV vaccine introduction, we are still a long way from herd immunity. The increase in high-risk types 31/33/45/52/58 will need to be reassessed when the nonavalent vaccine impact will be more reliable.

Age-related distribution of uncommon HPV genotypes in cervical intraepithelial neoplasia grade 3

AIM

Cervical cancer prevention guidelines include Human Papillomavirus (HPV) test, cytology, and HPV-16/18 typing for triage to determine the risk of cervical intraepithelial neoplasia (CIN) grade 3 as the best proxy of cervical cancer risk. In doing that, they do not consider how age can modify the type-specific risk of CIN3. The present study aimed to evaluate the age-related distribution of HPV genotypes affecting the risk-assessment in cervical cancer screening programs: non-screening-type-HPV and non-HPV-16/18 in unvaccinated women with CIN3.

METHODS

Retrospective multi-institutional study, including HPV genotyped women with CIN3 on cone histology treated between 2014 and 2019. The sample was divided into three categories of age: <30, 30-44, ≥45. HPV genotypes were grouped in non-screening-type-HPV (not-including genotypes 16/18/31/33/35/39/45/51/52/56/58/59/66/68) and non-HPV-16/18. Associations and trends between different age-groups and HPV genotypes were measured.

RESULTS

1332 women were analyzed. Non-screening-type-HPV CIN3 were 73 (5.5%). Non-HPV-16/18 were found in 417 participants (31.3%). Women over 45 associated with non-screening-type HPV [odds ratio (OR) = 1.87, 95% confidence interval (CI) 1.07-3.25; p = 0.027]. Non-screening-type-HPV prevalence increased significantly with age (3.9% vs 5.1% vs 9.0%, p = 0.016). Women under 30 showed a lower rate of non-HPV-16/18 (OR = 0.65, 95% CI 0.47-0.89; p = 0.007). There was a positive trend with age of non-HPV-16/18 CIN3 (23.6% vs 32.1% vs 38.0%, p = 0.0004).

CONCLUSION

The proportion of CIN3 lesions unrelated to genotypes detected by primary screening tests increased with age. This implies that age probably modifies the risk of CIN3 and possibly of cancer associated with HPV types. The risk-based recommendation should take into consideration age to define the management of HPV positive women.