Considerations for the Full Global Withdrawal of Oral Polio Vaccine After Eradication of Polio

Implementation challenges and real-world impacts of switching pediatric vaccines: A global systematic literature review

Switching a vaccine for another on a pediatric national immunization program is often done for the betterment of society. However, if poorly implemented, switching vaccines could result in suboptimal transitions with negative effects. A systematic review was conducted to evaluate the existing knowledge from identifiable documents on implementation challenges of pediatric vaccine switches and the real-world impact of those challenges. Thirty-three studies met the inclusion criteria. We synthesized three themes: vaccine availability, vaccination program deployment, and vaccine acceptability. Switching pediatric vaccines can pose unforeseen challenges to health-care systems worldwide and additional resources are often required to overcome those challenges. Yet, the magnitude of the impact, especially economic and societal, was frequently under-researched with variability in reporting. Therefore, an efficient vaccine switch requires a thorough consideration of the added benefits of replacing the existing vaccine, preparation, planning, additional resource allocation, implementation timing, public-private partnerships, outreach campaigns, and surveillance for program evaluation.

[Recurrent laryngeal papillomatosis]

Human papillomaviruses (HPV) 6 and 11 cause 90% of recurrent laryngeal papillomatosis (RLP). It is unclear whether recurrences are caused by new infections or the spread of infected cells. Symptomatic and sometimes curative treatment is laser surgery or conventional microsurgical removal. RLP surgery aims to relieve shortness of breath and improve the voice. Patients (especially children) are affected by voice problems, repetitive surgeries, pulmonary manifestations, and psychological trauma. Vaccination with Gardasil 9 (Merck & Co., Rahway, NJ, USA) prevents new infections with HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58 and induces vaccine antigen-specific antibodies and CD4+ T helper cells. According to current studies, RLP can be avoided with prophylactic vaccination. The treatment is associated with a general vaccination risk (European Medicines Agency approval: girls and boys from 9 years). Studies also show that the vaccine after removal of HPV-associated neoplasia/papilloma prevents recurrences. Extension of the vaccination recommendation to prevent recurrences of HPV-associated diseases in men may promote applicability and herd immunity. For rare and treatment-refractory cases with laryngotracheal involvement, systemic therapy with bevacizumab (e.g. Avastin; Genentech, San Francisco, CA, USA), a VEGF antibody, is a promising adjuvant treatment option.

A review of data systems for assessing the impact of HPV vaccination in selected high-income countries

INTRODUCTION

The introduction of effective human papillomavirus (HPV) vaccination, screening, and treatment programs has led the World Health Organization to call for the global elimination of cervical cancer. Assessing progress toward this goal is supported through monitoring vaccination coverage and its impact.

AREAS COVERED

We performed a targeted review to assess the characteristics of HPV-related data systems from seven high-income countries (HICs) that represented varied approaches, including Australia, Canada, France, Italy, Scotland, Sweden, and the United States (US). Included data systems focused on preventive and early detection measures: HPV vaccination and cervical screening programs, as well as HPV-related disease outcomes. Differences were observed in approach to development of data systems, along with variation in geographical scope and methods of data collection.

EXPERT OPINION

A challenge exists in how to best follow-up the ongoing global-scale elimination efforts in a comprehensive manner. These sources provide a wealth of information regarding the strengths and limitations of, and notable variation among, current data systems used in HICs. This review can inform improvements to existing prevention programs and the implementation of new programs in other countries, and thus support optimization of cervical cancer prevention policy.

The duration of tracheostomy dependence in patients with juvenile-onset recurrent respiratory papillomatosis

BACKGROUND

Tracheostomy is a vital therapy for juvenile-onset recurrent respiratory papillomatosis (JORRP) to maintain an adequate airway in an emergency, yet the relationship between cannulation duration and prognosis has not been extensively explored.

OBJECTIVES

To investigate the predictive influence of the duration of tracheostomy dependence on JORRP remission.

MATERIALS AND METHODS

A retrospective review of JORRP patients (n = 77) with tracheostomy treated in Beijing Tongren Hospital was performed.

RESULTS

The rate of decannulation was 72.7%. After decannulation for one year, the percentage of distal spread fell from 42.9 to 30.4%. Twenty-six of 77 patients (33.8%) had remission of their disease, 40 (51.9%) continued to have active disease while 11 (14.3%) died during follow-up. The cannulation duration was positively correlated with the overall duration of this disease (r = 0.6). The cut-off point of 34.9 months for cannulation duration indicated the highest predictive value of remission. Duration of cannulation >34.9 months (OR = 0.33) and distal spread (OR = 0.29) decreased odds of remission.

CONCLUSION

The study demonstrates that the time span before decannulation indicates the severity of disease and cannulation aggravates the distal spread. Patients with cannulation duration ≤ 34.9 months after tracheostomy are prone to possess a relatively pleasant prognosis.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Hypopharynx, Larynx, Trachea and Parapharyngeal Space

In this article, we review the chapter on tumors of the larynx, hypopharynx, trachea and parapharyngeal space in the new edition of the WHO book, focusing on the new developments in comparison to the previous edition. Squamous cell carcinoma (SCC) and its variants are by far the most common malignancies at these locations, with very limited new insights. The most important is the introduction of new targeted treatment-checkpoint inhibitors, with a new task for pathologists, who may help to predict the response to treatment by analyzing the expression of targeted proteins in biopsy samples. Precancerous lesions remain a controversial topic and, similarly to other organs, it is acceptable to use the terms "dysplasia" or "squamous intraepithelial lesion" (SIL), but there is a slight difference between low-grade dysplasia and low-grade SIL: in the former, mild atypia must be present, while the latter also includes hyperplastic epithelium without atypia. Two approaches have been proposed: a two-tiered system with low- and high-grade dysplasia/SIL and a three-tiered system with an additional category, carcinoma in situ. We are still searching for reliable diagnostic markers to surpass the subjectivity in biopsy diagnosis, with a few potential candidate markers on the horizon, e.g., stem cell markers. Other tumors are rare at these locations, e.g., hematolymphoid, neuroendocrine and salivary gland neoplasms, and are no longer included in Chapter 3. They must be diagnosed according to criteria described in specific chapters. The same holds true for soft tissue tumors, with the exception of cartilaginous neoplasms, which are still included in Chapter 3.

Real-world impact and effectiveness assessment of the quadrivalent HPV vaccine: a systematic review of study designs and data sources

INTRODUCTION

Vaccine effectiveness and impact studies are typically observational, generating evidence after vaccine launch in a real-world setting. For human papillomavirus (HPV) vaccination studies, the variety of data sources and methods used is pronounced. Careful selection of study design, data capture and analytical methods can mitigate potential bias in such studies.

AREAS COVERED

We systematically reviewed the different study designs, methods, and data sources in published evidence (1/2007-3/2020), which assessed the quadrivalent HPV vaccine effectiveness and impact on cervical/cervicovaginal, anal, and oral HPV infections, anogenital warts, lesions in anus, cervix, oropharynx, penis, vagina or vulva, and recurrent respiratory papillomatosis.

EXPERT OPINION

The rapid growth in access to real-world data allows global monitoring of effects of different public health interventions, including HPV vaccination programs. But the use of data which are not collected or organized to support research also underscore a need to develop robust methodology that provides insight of vaccine effects and consequences of different health policy decisions. To achieve the WHO elimination goal, we foresee a growing need to evaluate HPV vaccination programs globally. A critical appraisal summary of methodology used will provide timely guidance to researchers who want to initiate research activities in various settings.

Detection of human papillomavirus (HPV) DNA in benign laryngeal lesions and role of cigarette smoking as an inducing factor

The association of human papillomavirus (HPV) in laryngeal malignancies is largely known. This study evaluated the association between HPV and benign laryngeal lesions and also the role of smoking and alcohol consumption in increasing the prevalence of HPV in such benign lesions. Seventy-eight specimens of benign laryngeal lesions including 26 polyps, 26 dysplasia, and 26 other lesions such as nodules and cysts were enrolled in this study. Polymerase chain reaction (PCR) technique was used to detect HPV DNA in the tissues. The role of smoking and alcohol consumption in the prevalence of HPV was also evaluated through appropriate statistical tests. This study showed that the prevalence of HPV in benign laryngeal lesions was not statistically significant. The Cohen's effect size for comparing polyps vs. other lesions was nearly 0.7, indicating that HPV prevalence in laryngeal polyps may be clinically meaningful. Another finding in our study is the role of smoking in increasing the HPV prevalence in laryngeal polyps (P = 0.034). In benign laryngeal polyps, HPV prevalence may be clinically important. Smoking acts as a co-factor to induce HPV infection in laryngeal polyps in our study.

Pembrolizumab Induced Acute Persistent Airway Disease in a Patient with Recurrent Respiratory Papillomatosis (RRP)

OBJECTIVE

To present an uncommon but serious, recently identified complication of checkpoint inhibitor therapy in a patient treated with pembrolizumab infusion for disseminated recurrent respiratory papillomatosis (RRP).

METHODS

Case report.

RESULTS

A 43-year-old woman with underlying asthma developed acute hypoxic respiratory failure within 24 hours of her third infusion of pembrolizumab for treatment of intractable, disseminated recurrent respiratory papillomatosis. Pulmonary function testing revealed a severe intra-thoracic obstructive ventilatory defect. Discontinuation of pembrolizumab, ventilatory support, and treatment with systemic and inhaled corticosteroids resulted in resolution of respiratory failure; however, her underlying asthma remains poorly controlled.

CONCLUSION

To our knowledge, this case is the first report of pembrolizumab-induced obstructive respiratory failure in a patient being treated for RRP.

Efficacy and safety of human papillomavirus vaccination in HIV-infected patients: a systematic review and meta-analysis

The prophylactic vaccines available to protect against infections by HPV are well tolerated and highly immunogenic. People with HIV have a higher risk of developing HPV infection and HPV-associated cancers due to a lower immune response, and due to viral interactions. We performed a systematic review of RCTs to assess HPV vaccines efficacy and safety on HIV-infected people compared to placebo or no intervention in terms of seroconversion, infections, neoplasms, adverse events, CD4+ T-cell count and HIV viral load. The vaccine-group showed a seroconversion rate close to 100% for each vaccine and a significantly higher level of antibodies against HPV vaccine types, as compared to the placebo group (MD = 4333.3, 95% CI 2701.4; 5965.1 GMT EL.U./ml for HPV type 16 and MD = 1408.8, 95% CI 414.8; 2394.7 GMT EL.U./ml for HPV type 18). There were also no differences in terms of severe adverse events (RR = 0.6, 95% CI 0.2; 1.6) and no severe adverse events (RR = 0.6, 95% CI 0.9; 1.2) between vaccine and placebo groups. Secondary outcomes, such as CD4 + T-cell count and HIV viral load, did not differ between groups (MD = 14.8, 95% CI − 35.1; 64.6 cells/µl and MD = 0.0, 95% CI − 0.3; 0.3 log10 RNA copies/ml, respectively). Information on the remaining outcomes was scarce and that did not allow us to combine the data. The results support the use of the HPV vaccine in HIV-infected patients and highlight the need of further RCTs assessing the effectiveness of the HPV vaccine on infections and neoplasms.

Insights From Modeling Preventive Supplemental Immunization Activities as a Strategy to Eliminate Wild Poliovirus Transmission in Pakistan and Afghanistan

Many countries use supplemental immunization activities (SIAs) with oral poliovirus vaccine (OPV) to keep their population immunity to transmission high using preventive, planned SIAs (pSIAs) and outbreaks response SIAs (oSIAs). Prior studies suggested that investment in pSIAs saved substantial health and financial costs due to avoided outbreaks. However, questions remain about the benefits of SIAs, particularly with the recent introduction of inactivated poliovirus vaccine (IPV) into routine immunization in all OPV-using countries. The mounting costs of polio eradication activities and the need to respond to oSIAs threatens the use of limited financial resources for pSIAs, including in the remaining countries with endemic transmission of serotype 1 wild poliovirus (WPV1) (i.e., Pakistan and Afghanistan). A recent updated global poliovirus transmission model suggested that the Global Polio Eradication Initiative (GPEI) is not on track to stop transmission of WPV1 in Pakistan and Afghanistan. We use the updated global model to explore the role of pSIAs to achieve WPV1 eradication. We find that unless Pakistan and Afghanistan manage to increase the quality of bivalent OPV (bOPV) pSIAs, which we model as intensity (i.e., sufficiently high-coverage bOPV pSIAs that reach missed children), the model does not lead to successful eradication of WPV1. Achieving WPV1 eradication, the global objectives of the GPEI, and a successful polio endgame depend on effective and sufficient use of OPV. IPV use plays a negligible role in stopping transmission in Pakistan and Afghanistan and most other countries supported by the GPEI, and more IPV use will not help to stop transmission.

Immunogenicity of three sequential schedules with Sabin inactivated poliovirus vaccine and bivalent oral poliovirus vaccine in Zhejiang, China: an open-label, randomised, controlled trial

BACKGROUND

The globally synchronised introduction of inactivated poliovirus vaccine (IPV) and replacement of trivalent oral poliovirus vaccine (OPV) with bivalent OPV (bOPV) were successfully implemented in China's routine immunisation programme in May, 2016. In response to the global shortage of Salk-strain IPV, Sabin-strain IPV production was encouraged to develop and use in low-income and middle-income countries. We assessed the immunogenicity of the current routine poliovirus vaccination schedule in China and compared it with alternative schedules that use Sabin-strain IPV (sIPV) and bOPV.

METHODS

This open-label, randomised, controlled trial recruited healthy infants aged 60-75 days from two centres in Zhejiang, China. Eligible infants were full-term, due for their first polio vaccination, weighed more than 2·5 kg at birth, were healthy on physical examination with no obvious medical conditions, and had no contraindications to vaccination. Infants were randomly assigned (1:1:1) using permuted block randomisation (block size of 12) to one of three polio vaccination schedules, with the first, second, and third doses given at ages 2 months, 3 months, and 4 months, respectively: sIPV-bOPV-bOPV (1sIPV+2bOPV group; current regimen), sIPV-sIPV-bOPV (2sIPV+1bOPV group), or sIPV-sIPV-sIPV (3sIPV group). The primary endpoint was the proportion of infants with seroconversion to each of the three poliovirus serotypes 1 month after the third dose. Serious and medically important adverse events were monitored for up to 30 days after each vaccination. We assessed immunity in the per-protocol population (all children who completed all three vaccinations and had pre-vaccination and post-vaccination laboratory data) and safety in all children who received at least one dose of study vaccine. This trial is registered with Clinicaltrials.gov, NCT03147560.

RESULTS

Between May 1, 2016, and Dec 1, 2017, we enrolled and randomly assigned 528 eligible infants to one of the three treatment groups (176 in each group); 473 infants (158 in the 1sIPV+2bOPV group, 152 in the 2sIPV+1bOPV group, and 163 in the 3sIPV group) were included in the per-protocol population. 100% seroconversion against poliovirus types 1 and 3 was observed in all three groups. Infants who received an immunisation schedule containing bOPV had significantly higher antibody titres against poliovirus types 1 and 3 than did the sIPV-only group (2048 in all three treatment groups; p<0·0001). Seroconversion against type 2 poliovirus was observed in 98 (62%) infants in the 1sIPV+2bOPV group, 145 (95%) infants in the 2sIPV+1bOPV group, and 161 (99%) infants in the 3sIPV group. No serious adverse events occurred during the study; 14 minor, transient adverse events were observed, with no significant differences across study groups.

INTERPRETATION

All three study schedules were well tolerated and highly immunogenic against poliovirus types 1 and 3. Schedules containing two or three sIPV doses had higher seroconversion rates against poliovirus type 2 than did the schedule with a single dose of sIPV. Our findings support inclusion of two sIPV doses in the routine poliovirus vaccination schedule in China to provide better protection against poliovirus type 2 than provided by the current regimen.

FUNDING

Chinese Center for Disease Control and Prevention and China National Biotec Group Company.

Postoperative Systemic Acyclovir in Juvenile-Onset Recurrent Respiratory Papillomatosis: The Outcome

A prospective observational study was conducted consisting of 21 patients of Juvenile-onset recurrent respiratory papillomatosis, attending the Department of Otorhinolaryngology and Head Neck Surgery at our institution, who underwent surgical excision of the papillomas followed by oral acyclovir postoperatively. The study was aimed to observe the effect of systemic acyclovir on postoperative outcomes in children having recurrent respiratory papillomatosis undergoing primary surgical excision. It was observed that the mean interval between surgeries as well as the number of surgical interventions required was significantly lesser when acyclovir was used as a postoperative adjuvant than when surgery was done alone. Hence, the interval between successive surgeries, or in other words, the time interval between relapse of the disease could be prolonged significantly with the use of postoperative systemic acyclovir. Thus, the disease could be controlled for longer periods and repeated surgeries avoided.

HPV vaccination as preventive approach for recurrent respiratory papillomatosis - a 22-year retrospective clinical analysis

BACKGROUND

Recurrent respiratory papillomatosis (RRP) is a rare, benign disease of the aerodigestive tract, especially the larynx, caused by infection with the human papillomavirus (HPV) types 6 or 11. Current management focuses on surgical debulking with microdebrider of papillomatous lesions with or without concurrent adjuvant therapy, e.g. Cidofovir®. This retrospective study evaluates the results of patients treated at a department of the university clinic between 1990 and 2012 and compares the results of the conventional treatment with a new treatment approach using adjuvant vaccination with Gardasil®.

METHODS

A retrospective Kaplan Maier analysis of n = 24 patients diagnosed and treated with RPR was performed. The records were reviewed for gender, age at the time of first manifestation of disease and time to recurrence.

RESULTS

Only n = 2 (15.4%) of the n = 13 vaccinated patients developed a recurrence of the disease after a mean time of 54.9 months (SD: 9.5 months). All patients who were not vaccinated (n = 11; 100%) developed a relapse after a mean time of 12.3 months (SD: 9.72 months).

CONCLUSION

We propose that adjuvant HPV vaccination with Gardasil® might have a preventive effect in RRP by occluding new papilloma formation.

Breaking the Last Chains of Poliovirus Transmission: Progress and Challenges in Global Polio Eradication

Since the launch of the Global Polio Eradication Initiative (GPEI), paralytic cases associated with wild poliovirus (WPV) have fallen from ∼350,000 in 1988 to 22 in 2017. WPV type 2 (WPV2) was last detected in 1999, WPV3 in 2012, and WPV1 appeared to be localized to Pakistan and Afghanistan in 2017. Through continuous refinement, the GPEI has overcome operational and biological challenges far more complex and daunting than originally envisioned. Operational challenges had led to sustained WPV endemicity in core reservoirs and widespread dissemination to polio-free countries. The biological challenges derive from intrinsic limitations to the oral poliovirus vaccine: ( a) reduced immunogenicity in high-risk settings and ( b) genetic instability, leading to repeated outbreaks of circulating vaccine-derived polioviruses and prolonged infections in individuals with primary immunodeficiencies. As polio eradication enters its multifaceted endgame, the GPEI, with its technical, operational, and social innovations, stands as the preeminent model for control of vaccine-preventable diseases worldwide.

Planning for globally coordinated cessation of bivalent oral poliovirus vaccine: risks of non-synchronous cessation and unauthorized oral poliovirus vaccine use

BACKGROUND

Oral polio vaccine (OPV) containing attenuated serotype 2 polioviruses was globally withdrawn in 2016, and bivalent OPV (bOPV) containing attenuated serotype 1 and 3 polioviruses needs to be withdrawn after the certification of eradication of all wild polioviruses to eliminate future risks from vaccine-derived polioviruses (VDPVs). To minimize risks from VDPVs, the planning and implementation of bOPV withdrawal should build on the experience with withdrawing OPV containing serotype 2 polioviruses while taking into account similarities and differences between the three poliovirus serotypes.

METHODS

We explored the risks from (i) a failure to synchronize OPV cessation and (ii) unauthorized post-cessation OPV use for serotypes 1 and 3 in the context of globally-coordinated future bOPV cessation and compared the results to similar analyses for serotype 2 OPV cessation.

RESULTS

While the risks associated with a failure to synchronize cessation and unauthorized post-cessation OPV use appear to be substantially lower for serotype 3 polioviruses than for serotype 2 polioviruses, the risks for serotype 1 appear similar to those for serotype 2. Increasing population immunity to serotype 1 and 3 poliovirus transmission using pre-cessation bOPV supplemental immunization activities and inactivated poliovirus vaccine in routine immunization reduces the risks of circulating VDPVs associated with non-synchronized cessation or unauthorized OPV use.

CONCLUSIONS

The Global Polio Eradication Initiative should synchronize global bOPV cessation during a similar window of time as occurred for the global cessation of OPV containing serotype 2 polioviruses and should rigorously verify the absence of bOPV in immunization systems after its cessation.

Squamous Cell Papillomatosis in the Setting of Recurrent Respiratory Papillomatosis

A 23 year old male presented to the Otolaryngology clinic with 6 months of hoarseness and poor voice projection without improvement from speech therapy or medical anti-reflux medication. Upon examination he was found to have multiple polypoid lesions emanating from bilateral false vocal folds, left true vocal fold, and the anterior commissure. Biopsy and potassium titanyl phosphate (KTP) laser ablation with bevacizumab injection provided treatment and confirmed the clinical suspicion of squamous cell papilloma. Despite 3 years of treatment, the papillomatosis proved difficult to control, requiring a procedure approximately every 3 months. In an attempt to control the course of the disease the patient received a series of three bevacizumab and three cidofovir injections. Serial biopsies showed mild atypia within the squamous cell papillomas. Two separate biopsies confirmed presence of human papillomavirus (HPV) 6/11 via in situ hybridization with appropriate controls. There is promising research that the quadrivalent HPV (types 6, 11, 16, and 18) vaccine both reduces the disease burden in patients with active disease and reduces the incidence of recurrent respiratory papillomatosis (RRP). Other studies have shown that local immunologic dysregulation may play a role in RRP pathogenesis. Therefore new treatment options, to include PDL-1 blockade, offer hope in treating this benign condition with high morbidity and rare mortality.

Addressing the Challenges and Opportunities of the Polio Endgame: Lessons for the Future

The Global Commission for the Certification of the Eradication of Poliomyelitis certified the eradication of type 2 poliovirus in September 2015, making type 2 poliovirus the first human pathogen to be eradicated since smallpox. The eradication of type 2 poliovirus, the absence of detection of type 3 poliovirus worldwide since November 2012, and cornering type 1 poliovirus to only a few geographic areas of 3 countries has enabled implementation of the endgame of polio eradication which calls for a phased withdrawal of oral polio vaccine beginning with the type 2 component, introduction of inactivated poliovirus vaccine, strengthening of routine immunization in countries with extensive polio resources, and initiating activities to transition polio resources, program experience, and lessons learned to other global health initiatives. This supplement focuses on efforts by global partners to successfully launch polio endgame activities to permanently secure and sustain the enormous gains of polio eradication forever.