Molecular size distribution in pentavalent (A, C, Y, W, X) meningococcal polysaccharide conjugate vaccine by HPSEC-UV-MALS-RI method- a conceivable stability indicating parameter.

Molecular size distribution (MSD) of polysaccharides serves as a key parameter that directly correlates to the immunogenicity of vaccine. MSD at meningococcal polysaccharide (A, C, Y and W) or conjugate bulk level is well established under detailed pharmacopeial and WHO guidelines. We report here, a newly developed method for determination of molecular size distribution of pentavalent Meningococcal conjugate vaccine comprising of A, C, Y, W and X (MenFive). Although serogroup specific molecular size could not be estimated here; lot to lot consistency monitoring, molecular aggregates distribution in final lot, are key takeaways of this method. Determination of MSD in pentavalent fill finished product was quite challenging. Various columns/detectors combination, buffers, physico-chemical conditions (temperature, 2-8 °C, 25 °C, 40 °C and 60 °C; flow rate, 0.3 mL to 0.8 mL), liquid/lyophilized formulations, were explored. Polymer-based packed columns were explored for estimation for MSD by aqueous size exclusion chromatography, using combinations of- Shodex OHPAK SB 807 HQ, Shodex OHPAK SB 806 HQ, G6000 PWXL, coupled with guard Shodex OHPAK SB-G-6B. MenFive showed heterogenous distribution of molecules ranging from 200 to 19000 kDa, indicating its complex nature. However, 1000-8000 kDa was dominant range, comprising of ≥ 50 % distribution of molecules, in both liquid as well as lyophilized formulations, with average molecular weight around 6000-6500 kDa. The molar mass distribution after slicing would provide an insight to the conformation of molecules through its presentation as HMW, LMW, aggregates and subsequently, the presence of dominant population of molecules of a particular molecular weight and its total contribution in the sample.

Vaccination May Be Economically and Epidemiologically Advantageous Over Frequent Screening for Gonorrhea Prevention.

BACKGROUND: Gonorrhea's rapid development of antimicrobial resistance underscores the importance of new prevention modalities. Recent evidence suggests that a serogroup B meningococcal vaccine may be partially effective against gonococcal infection. However, the viability of vaccination and the role it should play in gonorrhea prevention are an open question. METHODS: We modeled the transmission of gonorrhea over a 10-year period in a heterosexual population to find optimal patterns of year-over-year investment of a fixed budget in vaccination and screening programs. Each year, resources could be allocated to vaccinating people or enrolling them in a quarterly screening program. Stratifying by mode (vaccination vs. screening), sex (male vs. female), and enrollment venue (background screening vs. symptomatic visit), we consider 8 different ways of controlling gonorrhea. We then found the year-over-year pattern of investment among those 8 controls that most reduced the incidence of gonorrhea under different assumptions. A compartmental transmission model was parameterized from existing literature in the US context. RESULTS: Vaccinating men with recent symptomatic infection, which selected for higher sexual activity, was optimal for population-level gonorrhea control. Given a prevention budget of $3 per capita, 9.5% of infections could be averted ($299 per infection averted), decreasing gonorrhea sequelae and associated antimicrobial use by similar percentages. These results were consistent across sensitivity analyses that increased the budget, prioritized incidence or prevalence reductions in women, or lowered screening costs. Under a scenario where only screening was implemented, just 5.5% of infections were averted. CONCLUSIONS: A currently available vaccine, although only modestly effective, may be superior to frequent testing for population-level gonorrhea control.

Prevalence, serogroup distribution and risk factors of Neisseria meningitidis carriage in high school and university students in Hungary.

Neisseria meningitidis causes life-threatening invasive meningococcal disease (IMD) with high mortality worldwide. Asymptomatic pharyngeal meningococcus colonisation is an important reservoir for the spread of the bacterium. The aim of this study was to determine N. meningitidis colonisation rates in asymptomatic high school and university students and to identify risk factors for carriage. Oropharyngeal swab samples and data from a self-reported questionnaire were obtained from overall 610 students, among them 303 university students and 307 high school students, aged between 15 and 31 years in Budapest, Hungary, between November 2017 and December 2018. Meningococcal carriage and serogroup of N. meningitidis were determined by RT-PCR from DNA extracted directly from the specimen. N. meningitidis was identified in 212 (34.8 %) of the participants. Significantly higher carriage rate was found among high school students (48.9 %) compared to university students (20.5 %). Peak of colonisation rate was among 17-19-year-old students (48.7 %). Most carriage isolates were non-typable (87.3 %). From the 212 meningococcus carriers, 19 were colonised by serogroup B (9 %), 5 by serogroup C (2.4 %), and 1 had serogroup Y (0.5 %). Significantly higher colonisation rate was found among males (42.4 %) than in females (33.1 %). Antibiotic use in the past 2 months has decreased the rate of meningococcal colonisation. Recent respiratory infection, active or passive smoking and attending parties have not influenced meningococcal colonisation rate significantly. In conclusion, we have found high asymptomatic meningococcus carriage rate among high school students and young adults, however, the majority of the colonizing meningococci were non-typable.

A Multivariate Probit Regression of the Uptake of Adolescent Vaccines Among Racial/Ethnic Minority Adolescents Before and During the COVID-19 Pandemic.

PURPOSE: The uptake of adolescent vaccines has improved over the years. However, research of the effects of the COVID-19 pandemic on this uptake among racial/ethnic minority adolescents has been limited. This study was conducted to compare the probability of uptake of the human papillomavirus (HPV); tetanus, diphtheria, and acellular pertussis (Tdap); and quadrivalent meningococcal conjugate (MenACWY) vaccines among racial/ethnic minority adolescents ages 13-17 years in 2019, 2020, and 2021. METHODS: Using a cross-sectional design to examine data from the National Immunization Survey-Teen (2019-2021), multivariate probit regression was used to model variation in uptake of these three adolescent vaccines (n = 38,128). The outcome measures were HPV, Tdap, and MenACWY vaccine uptake. RESULTS: The probability of uptake of HPV vaccine was higher in 2020 (Coef = 0.09 [95% confidence interval (CI), 0.03-0.16]) and 2021 (Coef = 0.07 [95% CI, 0.00-0.15]) than in 2019. The probability of uptake of MenACWY vaccine was higher in 2020 (Coef = 0.08 [95% CI, 0.02-0.15]) than in 2019. The probability of uptake of recommended vaccines varied among racial/ethnic minorities with non-Hispanic Black adolescents exhibiting higher probability of uptake of HPV vaccine (Coef = 0.10 [95% CI, 0.01-0.19]) than Tdap vaccine. U.S. Census region and insurance status were associated with the uptake of all recommended vaccines. DISCUSSION: Progress in the uptake of these recommended vaccines may not have been interrupted by the COVID-19 pandemic. Also, disparities in uptake of the recommended vaccines still exist despite increased uptake during the pandemic. Future research should examine the disparities as well as examine regional differences in the uptake of these three adolescent vaccines.

Calendario de inmunizaciones 2024 / immunisation schedule 2024

Calendario de Inmunizaciones 2024 de población infantil, escolar y adulta.

Calendario de inmunizaciones infantil 2024 / childhood immunisation schedule 2024

Calendario de inmunización para población infantil.

Effect of immunization registry-based provider reminder to initiate HPV vaccination at age 9, Washington state.

Human papillomavirus (HPV) vaccination rates are lower than Tetanus-diphtheria-pertussis (Tdap) and Meningococcal conjugate (MenACWY) rates, although the Advisory Committee on Immunization Practices recommends all three vaccines be given routinely at age 11-12. Evidence is mounting that children who initiate HPV vaccination starting at age 9 are more likely to complete the series on time. Washington state implemented a provider reminder through its immunization information system (WAIIS) in January 2023 to increase HPV vaccine initiation at 9-years-old by updating the forecasted recommended age for HPV from age 11 to 9. The effectiveness of provider reminders when implemented via an immunization information system (IIS) is poorly understood. We evaluated the impact of this forecast update using a seasonally adjusted interrupted time series regression of weekly HPV initiations at 9-years-old before and after implementation. We also examined time series trends of vaccine administration between 2018 and 2023 for HPV initiation at age 9, as well as Tdap, MenACWY and HPV initiation at age 11. The WAIIS forecast update doubled the weekly rate of HPV initiation among 9-year-olds in Washington state, although the weekly count of initiation at 9 remains far lower than initiations at 11. Jurisdictions wanting to increase HPV vaccine initiation at earlier ages should consider updating their forecast algorithm and investing in complementary evidence-based strategies such as provider and parent education, and clinic-based quality improvement efforts. The reach of IIS forecaster updates may be enhanced by working with administrators of electronic medical record systems to ensure parity of provider prompts with IIS.

Molecular characteristics of Neisseria meningitidis carriage strains in university students in Lithuania.

BACKGROUND: Neisseria meningitidis can be carried asymptomatically in the human oropharynx without causing symptoms. Meningococcal carriage is relevant to the epidemiology of invasive meningococcal disease (IMD). No carriage studies have been performed among the general population in Lithuania, whereas the incidence of IMD in Lithuania was among the highest in European countries from 2009 to 2019. RESULTS: We analyzed a total of 401 oropharyngeal samples collected from university students from December 2021 to February 2023 for N. meningitidis carriage using direct swab PCR assays and culture. The overall carriage prevalence based on both or either swab PCR or culture was 4.99%. PCR-based assays were used to characterize 15 carriage isolates, including detection of genogroup, multilocus sequence typing profile, and typing of antigens PorA and FetA. The most common carriage isolates were capsule null locus (cnl), accounting for 46.7%, followed by genogroups B (26.7%) and Y (13.3%). We also performed a molecular characterization of invasive N. meningitidis isolates collected during the COVID-19 pandemic and post-pandemic period to understand better the meningococcal carriage in the context of prevailing invasive strains. Despite the substantial decrease in the incidence of IMD during the 2020-2022 period, clonal complex 32 (CC32) of serogroup B continued to be the most prevalent IMD-causing CC in Lithuania. However, CC32 was not detected among carriage isolates. The most common CCs were CC269, CC198, and CC1136. The antigen peptide variants found in most carried isolates were classified as 'insufficient data' according to the MenDeVAR Index to evaluate the potential coverage by the 4CMenB vaccine. Nearly half of the isolates were potentially covered by the Men-Fhbp vaccine. Resistance to ciprofloxacin was detected only for one cnl isolate. All isolates were susceptible to penicillin and ceftriaxone. Our analysis identified frequent partying (≥ 4 times/month) as a risk factor for meningococcal carriage, whereas smoking, living in a dormitory, and previous COVID-19 illness were not associated with the carriage. CONCLUSIONS: Our study revealed a low prevalence of meningococcal carriage among university students in Lithuania. The carriage isolates showed genetic diversity, although almost half of them were identified as having a null capsule locus.

Meningococcal ACWY conjugate vaccine immunogenicity in adolescents with primary or secondary immune deficiencies, a prospective observational cohort study.

BACKGROUND: Immunization with meningococcal ACWY conjugate vaccine induces protective antibodies against invasive meningococcal disease (IMD) caused by serogroups A, C, W and Y. We studied MenACWY-TT vaccine immunogenicity in adolescents with a heterogenous group of primary and secondary immune deficiency including patients with systemic lupus erythematosus, mixed connective tissue disease, vasculitis, uveitis, 22Q11 syndrome, sickle cell disease, and patients who underwent stem cell transplantation for bone marrow failure. FINDINGS: We enrolled 69 individuals aged 14-18 years diagnosed with a primary or secondary immune deficiency in a prospective observational cohort study. All patients received a single dose of MenACWY-TT vaccine during the catch-up campaign 2018-19 because of the IMD-W outbreak in the Netherlands. Capsular polysaccharide-specific (PS) IgG concentrations against MenACWY were measured before and 3-6, 12, and 24 months after vaccination. Overall, geometric mean concentrations (GMCs) of MenACWY-PS-specific IgG were lower in patients compared to data from healthy, aged-matched controls (n = 75) reaching significance at 12 months postvaccination for serogroup A and W (adjusted GMC ratios 0.26 [95% CI: 0.15-0.47] and 0.22 [95% CI: 0.10-0.49], respectively). No serious adverse events were reported by study participants. CONCLUSIONS: The MenACWY conjugate vaccine was less immunogenic in adolescent patients with primary or secondary immunodeficiency compared to healthy controls, urging the need for further surveillance of these patients and supporting considerations for booster MenACWY conjugate vaccinations in these patient groups.

Vaccination schedule for adolescents. Consensus of the AEV, CAV-AEP and SEMA.

We present the consensus document on the immunization schedule for adolescents developed by 3 scientific societies: the Spanish Association of Pediatrics (AEP), through its Advisory Committee on Vaccines (CAV-AEP), the Spanish Society of Adolescent Medicine (SEMA) and the Spanish Association of Vaccinology (AEV). There are particularities in infectious disease during adolescence, such as an increased susceptibility to pertussis, poorer outcomes of chickenpox, mumps and hepatitis A, a high incidence of sexually transmitted infections or increased prevalence of meningococcal carriage. The document analyses the schedule for adolescents in the context of vaccination policy overall. It contemplates the vaccines to be included in the immunization schedule for healthy adolescents: against invasive meningococcal disease (tetravalent ACWY and B), against human papillomavirus (which should be gender-neutral), against pertussis, against influenza and against SARS-CoV-2 (in unvaccinated individuals and at-risk groups). It is worth noting that the 4CMenB vaccine appears to confer some protection against gonococcal infection, which would be a considerable added value for adolescents. The vaccination of adolescents belonging to risk groups or travelling abroad also needs to be contemplated, as is the case in any other age group. Vaccination against hepatitis A, which is included in the routine immunization schedule of Catalonia, Ceuta and Melilla from the second year of life, should also be considered a priority in adolescents traveling to endemic areas.

Missed Opportunities for Adolescent Immunizations at Well-Care Visits During the COVID-19 Pandemic.

PURPOSE: The Coronavirus Disease 2019 pandemic disrupted healthcare, but the impact on vaccination missed opportunities (MOs, vaccine-eligible visits without vaccination) is unknown. We evaluated pandemic-related trends in MOs at adolescent well-care visits for three vaccines: human papillomavirus; quadrivalent meningococcal conjugate; and tetanus, diphtheria, and acellular pertussis (Tdap). METHODS: We analyzed electronic health record data from 24 pediatric primary care practices in 13 states from 1/1/2018 to 12/31/2021. Segmented logistic regression estimated risk differences for MOs during the pandemic relative to prepandemic trends. RESULTS: Among 106,605 well-care visits, we observed decreases in MOs prepandemic followed by an increase in MOs during the pandemic for all three vaccines. Relative to prepandemic, MOs increased for human papillomavirus (+15.9%, 95% confidence interval [CI]: 11.7%, 20.1%), meningococcal conjugate (+9.4%, 95% CI: 5.2%, 13.7%), and tetanus, diphtheria, and acellular pertussis (Tdap) (+ 8.2%, 95% CI: 4.3%, 12.1%). DISCUSSION: Increases in vaccine MOs during the pandemic equaled or exceeded pre-pandemic decreases. Reducing MOs in adolescent well-care could raise vaccine coverage.

An adenoviral-vectored vaccine confers seroprotection against capsular group B meningococcal disease.

Adenoviral-vectored vaccines are licensed for prevention of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Ebola virus, but, for bacterial proteins, expression in a eukaryotic cell may affect the antigen's localization and conformation or lead to unwanted glycosylation. Here, we investigated the potential use of an adenoviral-vectored vaccine platform for capsular group B meningococcus (MenB). Vector-based candidate vaccines expressing MenB antigen factor H binding protein (fHbp) were generated, and immunogenicity was assessed in mouse models, including the functional antibody response by serum bactericidal assay (SBA) using human complement. All adenovirus-based vaccine candidates induced high antigen-specific antibody and T cell responses. A single dose induced functional serum bactericidal responses with titers superior or equal to those induced by two doses of protein-based comparators, as well as longer persistence and a similar breadth. The fHbp transgene was further optimized for human use by incorporating a mutation abrogating binding to the human complement inhibitor factor H. The resulting vaccine candidate induced high and persistent SBA responses in transgenic mice expressing human factor H. The optimized transgene was inserted into the clinically relevant ChAdOx1 backbone, and this vaccine has now progressed to clinical development. The results of this preclinical vaccine development study underline the potential of vaccines based on genetic material to induce functional antibody responses against bacterial outer membrane proteins.

Adherence to vaccination guidelines of patients with complete splenectomy in Norway, 2008-2020.

The spleen is responsible for blood filtration and mounting an immune response against pathogens. In some people the spleen must be surgically removed because of traumatic events or oncological and hematological conditions. These patients are at higher risk of developing diseases caused by encapsulated bacteria throughout their lives. Thus, immunisations are advised for splenectomised persons to prevent infection caused by Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae type b (Hib). This study assessed vaccination coverage (VC) among Norwegian patients with surgical asplenia. Using the Nomesco Classification of Surgical Procedures codes, patient information (age, sex, date of initial diagnosis and date of surgery) was acquired from the Norwegian Patient Registry. The National Immunization Register provided information on vaccination status and data of any subsequent invasive bacterial infections were obtained from the Norwegian Surveillance System for Communicable Diseases. From the total population of Norway, 3155 patients who had undergone complete splenectomy were identified. Of these, 914 (29.0%) had received at least one dose of pneumococcal conjugate vaccine (PCV), 1324 (42.0%) at least one dose of pneumococcal polysaccharide vaccine and 589 (18.7%) had received both. Only 4.2% of the patients had received two doses of a meningococcal ACWY conjugate vaccine, while 8.0% of 1467 patients splenectomised after 2014 had received at least two doses of a serogroup B meningococcal vaccine. The VC for Hib was 18.7%. Nearly all splenectomised children under the age of 10 were vaccinated with Hib and PCV as these vaccines are included in the childhood immunisation program. For all vaccines, VC decreased with age. Twenty-nine invasive bacterial infections were registered post-splenectomy in 25 patients. Vaccination according to national recommendations could have prevented at least 8 (28%) of these infections. Our study showed that efforts are required to increase VC of splenectomised individuals in Norway.

Barriers and facilitators to HPV and meningococcal vaccination among men who have sex with men: a qualitative study.

BACKGROUND: Men who have sex with men (MSM) have suboptimal uptake of human papillomavirus (HPV) and meningococcal vaccines. This study examines barriers and facilitators to HPV and meningococcal vaccination among MSM in a large, racially/ethnically diverse, and medically underserved U.S. region. METHODS: In 2020, we conducted five focus groups with MSM living in the Inland Empire, California. Participants discussed (1) their knowledge about and attitudes toward HPV, meningococcal disease, and related vaccines; and (2) factors that would encourage or discourage vaccine uptake. Data were systematically analyzed to identify salient barriers and facilitators to vaccination. RESULTS: Participants (N = 25) had a median age of 29. Most were Hispanic (68%), self-identified as gay (84%), and had college degrees (64%). Key barriers to vaccination included: (1) limited awareness and knowledge about HPV and meningococcal disease, (2) reliance on mainstream healthcare providers for vaccine information, (3) stigma and reluctance to disclose sexual orientation, (4) uncertainty about health insurance coverage and vaccine costs, and (5) distance and time required to access vaccines. Key facilitators to vaccination were: (1) vaccine confidence, (2) perceived severity of HPV and meningococcal disease, (3) bundling vaccination into routine healthcare, and (4) pharmacies as vaccination sites. CONCLUSIONS: Findings highlight opportunities for HPV and meningococcal vaccine promotion, including targeted education and awareness campaigns for MSM, LGBT inclusivity training for healthcare providers, and structural interventions to improve vaccine accessibility.

Human papillomavirus vaccination at the first opportunity: An overview.

The Advisory Committee on Immunization Practices (ACIP) has recommended human papillomavirus (HPV) vaccination for adolescents in the United States since 2006. Though recommended at a similar time to the routine recommendations for adolescent tetanus, diphtheria, and acellular pertussis vaccination (Tdap) and quadrivalent meningococcal vaccination (MCV4), HPV vaccine uptake has consistently lagged behind these other adolescent vaccines. The ACIP recommends HPV vaccination at 11-12 y, with vaccination starting at 9 y of age included as an option that is routinely encouraged by the American Academy of Pediatrics and American Cancer Society. To support efforts to increase HPV vaccination at the first opportunity, this commentary summarizes the current HPV vaccination recommendations and available evidence regarding HPV vaccination starting at 9 y - including recent studies and trials documenting the effectiveness of HPV vaccination at 9 in supporting vaccine series completion, while providing future directions for research and implementation to improve HPV vaccination.

Descriptive epidemiology of age at HPV vaccination: Analysis using the 2020 NIS-Teen.

Human papillomavirus (HPV) vaccination uptake in the United States remains suboptimal, and continues to trail that of tetanus, diphtheria, and acellular pertussis (Tdap) vaccination and quadrivalent meningococcal conjugate vaccination (MCV4). This is despite these three vaccines all being recommended for routine adolescent use within the 2005-2006 time period. One strategy to improve HPV vaccination is starting the vaccine series at the first opportunity - currently as young as 9 years of age. Little is known about the epidemiology of age at HPV vaccination, and the frequency of vaccination occurring at 9-10 years of age. Using 2020 National Immunization Survey-Teen (NIS-Teen) data, we analyzed age at HPV vaccine initiation and proportion of initiators completing the HPV vaccine series relative to age at initiation. Overall, 4.0% of US adolescents initiated HPV vaccination at 9-10 years of age, with higher initiation among younger birth cohorts (4.8% for 13-year-olds and 5.1% for 14-year-olds) than older cohorts (3.1% for both 16 and 17 year-olds). Age cohorts maximized HPV vaccine completion after 3-4 years. Among those initiating at ages 9-10, 93% of 13-year-olds completed the series. Among those initiating at 11-12, completion rates rose from 66% among 13-year-olds to 90.2% among 16-year-olds. Among those initiating at age 13-14, completion rose from 61% among 15-year-olds to 84.9% among 17-year-olds. This manuscript serves as a starting point of comparison for future epidemiologic evaluations of HPV vaccination at the first opportunity.

Optimizing timing of adolescent vaccines: Impact of initiating HPV vaccination before Tdap or meningococcal vaccination on timely completion of the HPV vaccine series.

To explore the impact on timely series completion of initiating the HPV vaccine series prior to other vaccines in the adolescent platform (Tdap or meningococcal vacccines), we created a cohort of children aged 9 in 2015 who were continuously enrolled through the age of 13 (2019) from a national administrative database of employee-sponsored insurance in the United States (MarketScan). Logistic regressions were used to predict the odds of HPV vaccine series completion among those who started the series prior to, concurrent with, or after receiving Tdap or meningococcal vaccination. The cohort included 100,857 eligible children. Compared with adolescents who received their HPV and Tdap or HPV and meningococcal vaccinations concurrently, those who received HPV prior to other vaccines had higher completion (aOR = 1.38 for Tdap, aOR 1.62 for meningococcal), while those who received their HPV vaccination after other vaccines had lower odds of HPV vaccine series completion (aOR = 0.68 for Tdap, aOR = 0.62 for meningococcal). Other factors associated with series completion included female sex, residing in an urban (vs. rural) area, residing in the Northeast, and receiving primary care from a pediatrician (vs. family medicine physician). These data indicate that beginning the HPV vaccine series prior to the adolescent platform may improve on-time series completion.

Meningococcus B Vaccination Effectiveness Against Neisseria gonorrhoeae Infection in People Living With HIV: A Case-Control Study.

BACKGROUND: We assessed the vaccination effectiveness (VE) of multicomponent meningococcal serogroup B (4CMenB) vaccine against gonorrhea among people living with HIV (PLWH) with a previous diagnosis of sexually transmitted infection. METHODS: Unmatched case-control study on men who have sex with men living with HIV, in care at San Raffaele Scientific Institute, Milan, Italy, with gonorrhea, syphilis, chlamydia, or anal human papillomavirus between July 2016 (beginning of 4CMenB vaccination) and February 2021 (date of freezing). For the analysis, cases were people with ≥1 gonorrhea infection since July 2016, and controls were people with ≥1 syphilis, chlamydia, or anal human papillomavirus infection since July 2016. Logistic regression was used to provide the estimate of 4CMenB VE against gonorrhea. RESULTS: Included people living with HIV were 1051 (103 cases, 948 controls); 349 of 1051 (33%) received 2 doses of 4CMenB vaccination. The median follow-up was 3.8 years (2.1-4.3 years). The unadjusted estimate for VE against gonorrhea was 42% (95% confidence interval, 6%-64%; P = 0.027). Logistic regression showed that VE against gonorrhea remained significant (44%; 95% confidence interval, 9%-65%; P = 0.020) after adjusting for some factors that might have a potential influence on VE or those with significant unbalanced distributions between cases and controls at univariable analysis. CONCLUSIONS: 4CMenB vaccination is associated with a lower risk of gonorrhea in the setting of men who have sex with men living with HIV with a previous sexually transmitted infection.

School immunization coverage in adolescents during the COVID-19 pandemic: A retrospective cohort study.

INTRODUCTION: Few studies have assessed the impact of the coronavirus disease 2019 (COVID-19) pandemic on immunization coverage for adolescents, and little is known about how coverage has changed throughout the pandemic. We aimed to: (1) assess the change in coverage for school-based vaccines in Alberta, Canada resulting from the pandemic; (2) determine whether coverage differed by geographic health zone and school type; and (3) ascertain whether coverage has returned to pre-pandemic levels. METHODS: Using a retrospective cohort design, we used administrative health data to compare coverage for human papillomavirus (HPV) and meningococcal conjugate A, C, Y, W-135 (MenC-ACYW) vaccines between pre-pandemic (2017-2018 school year) and pandemic (2019-2020 and 2020-2021 school years) cohorts (N = 289,420). Coverage was also compared by health zone and authority type. The 2019-2020 cohort was followed over one year to assess catch-up. RESULTS: Compared to 2017-2018, immunization coverage for HPV was significantly lower in the 2019-2020 (absolute difference: 60.8%; 95% CI: 60.4-61.3%) and 2020-2021 cohorts (absolute difference: 59.9%; 95% CI: 59.4-60.3%). There was a smaller, significant decline in MenC-ACYW coverage comparing 2017-2018 to 2019-2020 (absolute difference: 6.1%; 95% CI: 5.6-6.5%) and 2020-2021 (absolute difference: 32.2%; 95% CI: 31.6-32.7%). Private schools had low coverage overall, while coverage fluctuated by zone. During follow-up of the 2019-2020 cohort, coverage for HPV and MenC-ACYW increased from 5.6% to 50.2%, and 80.7% to 83.0%, respectively. CONCLUSION: There was a substantial decrease in school-based immunization coverage during the COVID-19 pandemic, and coverage has not returned to pre-pandemic levels, suggesting further catch-up is needed.