Vaccine Knowledge of Saudi Parents and Adherence to Immunization Schedule in Saudi Arabia

Objectives: Immunization is one of the best measures to limit the transition of infectious disease and disease severity. Despite that, vaccination programs are frequently affected by a delay in giving vaccines on time or ignorance and avoidance due to various reasons. Our study aimed to estimate the percentage of vaccination delay in our society and assess the level of parents' awareness about vaccine importance;finally, we will shed light on the effect of the coronavirus pandemic on the immunization schedule. Methods: This cross-sectional study was conducted in Dawadmi, Saudi Arabia, from May 2022 to August 2022. Data were collected from parents using a structured questionnaire. Vaccinations were considered delayed if they occurred more than 30 days after the designated time. Parents residing outside Dawadmi or older than 65 years were excluded. Results: Among 393 respondents, the majority were mothers, aged between 30-50 years. Overall, 88% adhered to the immunization schedule. Major reasons for delay were forgetting the vaccination date, unavailability of vaccines, and being busy at work. In comparison to the delayed group, parents who adhered to the immunization schedule were aware about its importance. Conclusions: The majority of parents adhered to the immunization schedule. The most common reason was forgetting the vaccine date. Other reasons were the lack of vaccines in Primary Health Care. The commonly delayed vaccines were the 4 and 9-months vaccines. The pandemic affected adherence to vaccination schedules.

Multi-level quality improvement strategies to optimize HPV vaccination starting at the 9-year well child visit: Success stories from two private pediatric clinics.

HPV vaccination rates remain far below goal, leaving many adolescents unprotected against future HPV-related cancers. Starting HPV vaccine at age 9 may improve timely preteen vaccination. The "HPV Vax at 9" Quality Improvement intervention paired HPV vaccination with 9- and 10-year well child visits and was piloted at two pediatric clinics (n = 9 sites) in Washington between 2018 and 2022. Supporting interventions included standardized immunization schedule posters in exam rooms, electronic medical record supports, provider and staff training, strong provider recommendations, printed educational resources, and peer-to-peer champion coaching. Provider and clinic acceptance was high with HPV vaccine administration occurring at 68-86% of the 9- and 10-year well child visits. During the first year, HPV initiation rates at age 9-10 increased by 30% or more at each clinic. Sustained improvements in initiation and series completion were seen with completion at age 11-12 rising as much as 40% from 22 to 62%. Downward pressure of the COVID-19 pandemic on HPV vaccination rates was mitigated. Pairing HPV vaccine with 9- and 10-year well child visits, posting the standardized immunization schedule, and instituting EMR supports for HPV at 9 may be effective and sustainable strategies to simplify clinic workflows and increase timely HPV vaccination.

Recommendations for modernizing infant vaccination schedules with combination vaccines in Colombia and Peru.

The objective of this article was to consider the vaccination challenges in Colombia and Peru and the role of pediatric combination vaccines in overcoming these challenges. Barriers to including new vaccines with more antigens remain apparent in parts of these countries, where vaccine-preventable diseases in infants continue to be a major problem. The challenges include the heterogeneity of vaccine coverage within each country and in neighboring countries, which can contribute to poor rates of vaccination coverage; the adverse impact of the inward migration of unvaccinated individuals, which has favored the re-emergence of vaccine-preventable diseases; vaccine shortages; and the impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and the associated shifts in health care resources. To improve the coverage of pediatric vaccines in Colombia and Peru, it will be necessary to ensure the widespread integration into vaccine schedules of combination vaccines containing diphtheria, tetanus, acellular pertussis, inactivated poliovirus, Haemophilus influenzae type b and hepatitis B antigens with a three-dose primary series delivered at 2, 4 and 6 months of age followed by a booster at 18 months of age. Such vaccines play important roles in preventing diphtheria, tetanus and pertussis; eradicating polio; and providing boosting against H. influenzae type b.

El objetivo de este artículo es considerar los desafíos que se enfrentan en Colombia y Perú con respecto a la vacunación y el papel de las vacunas combinadas pediátricas para superar estos desafíos. Los obstáculos para incluir vacunas nuevas con más antígenos siguen siendo evidentes en algunos lugares de estos países, donde las enfermedades prevenibles por vacunación en menores de 1 año continúan siendo un grave problema. Entre los desafíos se incluye la heterogeneidad de la cobertura de vacunación en cada país y en los países vecinos, lo que puede contribuir con que se registren tasas bajas de cobertura de vacunación; el impacto adverso de la migración interna de personas no vacunadas, lo que ha favorecido la reaparición de enfermedades prevenibles por vacunación; la escasez de vacunas, y el impacto de la pandemia del coronavirus de tipo 2 causante del síndrome respiratorio agudo grave (SARS-CoV-2) y los consiguientes cambios en los recursos de atención médica. Para mejorar la cobertura de las vacunas pediátricas en Colombia y Perú será necesario integrar de manera generalizada en los calendarios de vacunación vacunas combinadas con antígenos de difteria, tétanos, tos ferina acelular, poliovirus inactivados, Haemophilus influenzae tipo b y hepatitis B con una serie primaria de tres dosis administradas a los 2, 4 y 6 meses de edad, seguida de un refuerzo a los 18 meses de edad. Esas vacunas desempeñan un papel esencial en la prevención de la difteria, el tétanos y la tos ferina; la erradicación de la polio; y el refuerzo contra H. influenzae tipo b.

O objetivo deste artigo foi avaliar os desafios da vacinação na Colômbia e no Peru e o papel das vacinas pediátricas combinadas na superação de tais desafios. Os obstáculos para incluir novas vacinas com mais antígenos permanecem visíveis em partes desses países, onde doenças imunopreveníveis em lactentes continuam a ser um grande problema. Os desafios incluem a heterogeneidade da cobertura vacinal dentro de cada país e nos países vizinhos, o que pode contribuir para baixas taxas de cobertura vacinal; o impacto adverso da migração interna de pessoas não vacinadas, o que favoreceu o ressurgimento de doenças imunopreveníveis; a escassez de vacinas; e o impacto da pandemia de síndrome respiratória aguda grave do coronavírus 2 (SARS-CoV-2) e mudanças relacionadas nos recursos de atenção à saúde. Para melhorar a cobertura das vacinas pediátricas na Colômbia e no Peru, será necessário assegurar sua integração generalizada em esquemas de vacinas combinadas contendo antígenos de difteria, tétano, pertussis acelular, poliovírus inativado, Haemophilus influenzae tipo B e hepatite B, com uma série primária de três doses aplicadas aos 2, 4 e 6 meses de idade seguidas de um reforço aos 18 meses de idade. Tais vacinas desempenham papéis importantes na prevenção da difteria, tétano e coqueluche; na erradicação da poliomielite; e no reforço contra H. influenzae tipo b.

Review of scientific evidence to support recommendations of the full-dose DTaP-IPV vaccination in pre-school age children in Italy.

INTRODUCTION: Two vaccine formulations are available to prevent diphtheria, tetanus, pertussis, and poliomyelitis: the pediatric full-dose (DTaP-IPV) and the reduced dose formulation (dTap-IPV). Different immunization schedules are internationally recommended for the pre-school booster dose. AREAS COVERED: International and Italian recommendations, scientific evidence on immunogenicity and safety of DTaP/dTap vaccines to support the full dose as a pre-school booster and Italian vaccination coverage (VC) up to adolescence. EXPERT OPINION: The WHO recommends a '3+1' schedule with DTaP vaccine for primary immunization, followed by a pre-school booster with DTaP or dTap vaccine. In Italy, a '2+1' schedule, with no booster in the second year, and a pre-school booster dose are recommended with DTPa-IPV vaccines. Studies showed a non-inferior immunogenicity in dTap vaccinees in pre-school age; nevertheless, the antibody titers were usually greater in children vaccinated with DTaP, while lower frequencies of adverse events were recorded in children receiving dTap. Italian VCs for pre-school and adolescent boosters have not been satisfactory, which further reduced during the COVID-19 period. In Italy, the pre-school booster offers the last chance to receive a full dose of DTaP vaccine, thus, representing the most suitable intervention to provide lasting protection in children.

Immunisation resources for nurses

The article offers medical news briefs in United Kingdom (UK), including the immunisation leaflet for migrants published by the UK Health Security Agency (UKHSA), and the competence assessment tool for immunisers published by the Royal College of Nursing.

Impact of the COVID-19 Pandemic on Human Papillomavirus Vaccination in Brazil.

Objective: To analyze the number of applied HPV vaccine doses before (from April 2019 to March 2020) and after (from April 2020 to September 2020) social distancing measures in response to the COVID-19 pandemic in states and regions of Brazil. Methods: Ecological time-series study, using data from the Brazilian National Immunization Program (PNI). Using the Mann-Whitney test, we evaluated the difference between the median number of applied doses during the periods April 2019 to March 2020 and from April 2020 to September 2020. Spatial analysis identified clusters with a high or low percentage reduction in the median applied doses. Prais-Winsten regression models identified temporal trends in the applieddoses from both periods. Results: There was a significant reduction in the median HPV vaccine doses applied, formation of spatial clusters and, after a sharp drop in the number of applieddoses during the months following social distancing. There was a tendency to increase the applied vaccines doses. Conclusion: The COVID-19 pandemic resulted in reduction of the number of HPV vaccine doses applied as a possible effect of restrictive measures caused by the pandemic.

Delay in childhood vaccinations during the COVID-19 pandemic.

OBJECTIVES: In many jurisdictions, routine medical care was reduced in response to the COVID-19 pandemic. The objective of this study was to determine whether the frequency of on-time routine childhood vaccinations among children age 0-2 years was lower following the COVID-19 declaration of emergency in Ontario, Canada, on March 17, 2020, compared to prior to the pandemic. METHODS: We conducted a longitudinal cohort study of healthy children aged 0-2 years participating in the TARGet Kids! primary care research network in Toronto, Canada. A logistic mixed effects regression model was used to determine odds ratios (ORs) for delayed vaccination (> 30 days vs. ≤ 30 days from the recommended date) before and after the COVID-19 declaration of emergency, adjusted for confounding variables. A Cox proportional hazards model was used to explore the relationship between the declaration of emergency and time to vaccination. RESULTS: Among 1277 children, the proportion of on-time vaccinations was 81.8% prior to the COVID-19 declaration of emergency and 62.1% after (p < 0.001). The odds of delayed vaccination increased (odds ratio = 3.77, 95% CI: 2.86-4.96), and the hazard of administration of recommended vaccinations decreased after the declaration of emergency (hazard ratio = 0.75, 95% CI: 0.60-0.92). The median vaccination delay time was 5 days (95% CI: 4-5 days) prior to the declaration of emergency and 17 days (95% CI: 12-22 days) after. CONCLUSION: The frequency of on-time routine childhood vaccinations was lower during the first wave of the COVID-19 pandemic. Sustained delays in routine vaccinations may lead to an increase in rates of vaccine-preventable diseases.

RéSUMé: OBJECTIFS: Dans plusieurs juridictions, les soins médicaux systématiques étaient réduits à cause de la pandémie de COVID-19. L'objectif de cette étude était de déterminer si la fréquence de donner les vaccinations systématiques aux enfants de l'âge de 0 à 2 ans était réduite en conséquence de la déclaration d'urgence de COVID-19 en Ontario, Canada dès le 17 mars 2020, comparer avec la fréquence avant la pandémie. MéTHODES: Nous avons mené une étude de cohorte longitudinale des enfants en bonne santé âgés de 0 à 2 ans qui participent dans le réseau de recherche en soins primaires TARGet Kids! à Toronto, Canada. Un modèle de régression logistique à effets mixtes était utilisé pour déterminer le rapport de cotes (RC) pour les vaccinations retardées (> 30 jours c. ≤ 30 jours de la date recommandée) et était équilibré pour les variables confondantes. Le modèle à risques proportionnels de Cox était utilisé pour examiner le lien entre la déclaration d'urgence et le temps jusqu'à la vaccination. RéSULTATS: Parmi 1 277 enfants, la proportion de vaccination à l'heure était 81,8 % avant la déclaration d'urgence de COVID-19 et 62,1 % après (p < 0,001). La possibilité de vaccination retardée était augmentée (RC = 3,77; IC95% : 2,86­4,96), et le taux d'administration recommandé pour les vaccinations était réduit après la déclaration d'urgence (ratio de hasard = 0,75; IC95% : 0,60­0,92). Le médian temps de retard pour les vaccinations était 5 jours (IC95% : 4­5 jours) avant la déclaration d'urgence et 17 jours (IC95% : 12­22 jours) après. CONCLUSION: La fréquence de vaccinations systématiques aux enfants à l'heure était inférieure pendant la première vague de la pandémie COVID-19. Des retards soutenus pour recevoir les vaccinations systématiques peuvent entrainer une augmentation des taux de maladies évitables par la vaccination.

Should We Delay the Second COVID-19 Vaccine Dose in Order to Optimize Rollout? A Mathematical Perspective.

Objectives: With vaccination shortage persisting in many countries, adopting an optimal vaccination program is of crucial importance. Given the slow pace of vaccination campaigns globally, a very relevant and burning public health question is whether it is better to delay the second COVID-19 vaccine shot until all priority group people have received at least one shot. Currently, many countries are looking to administer a third dose (booster shot), which raises the question of how to distribute the available daily doses to maximize the effectively vaccinated population. Methods: We formulate a generalized optimization problem with a total of u T = ∑ i = 1 n u i vaccine doses, that have to be optimally distributed between n different sub-populations, where sub-population u i represents people receiving the ith dose of the vaccine with efficacy α i . The particular case where n = 2 is solved first, followed by the general case of n dose regimen. Results: In the case of a two dose regimen, if the efficacy of the second dose is less than (or equal to) twice the efficacy of the first dose, the optimal strategy to maximize the number of effectively vaccinated people is to delay the second vaccine as much as possible. Otherwise, the optimal strategy would consist of administering the second dose as quickly as possible. In the general case, the optimal vaccination strategy would be to administer the k - th dose corresponding to the index providing the maximum inter-dose efficacy difference (α i - α i-1) for all possible values of i ∈ {1, … , n}, with α 0 = 0. Conclusion: Our results suggest that although extending the interval between doses beyond 12 weeks was likely optimal earlier in the pandemic, the reduced single dose efficacy of vaccines against the delta variant make this approach no longer viable.

A randomized, double-blind phase I clinical trial of two recombinant dimeric RBD COVID-19 vaccine candidates: Safety, reactogenicity and immunogenicity.

BACKGROUND: The Receptor Binding Domain (RBD) of the SARS-CoV-2 spike protein is the target for many COVID-19 vaccines. Here we report results for phase I clinical trial of two COVID-19 vaccine candidates based on recombinant dimeric RBD (d-RBD). METHODS: We performed a randomized, double-blind, phase I clinical trial in the National Centre of Toxicology in Havana. Sixty Cuban volunteers aged 19-59 years were randomized into three groups (20 subjects each): 1) FINLAY-FR-1 (50 µg d-RBD plus outer membrane vesicles from N. meningitidis); 2) FINLAY-FR-1A-50 (50 µg d-RBD, three doses); 3) FINLAY-FR-1A-25 (25 µg d-RDB, three doses). The FINLAY-FR-1 group was randomly divided to receive a third dose of the same vaccine candidate (homologous schedule) or FINLAY-FR-1A-50 (heterologous schedule). The primary outcomes were safety and reactogenicity. The secondary outcome was vaccine immunogenicity. Humoral response at baseline and following each vaccination was evaluated using live-virus neutralization test, anti-RBD IgG ELISA and in-vitro neutralization test of RBD:hACE2 interaction. RESULTS: Most adverse events were of mild intensity (63.5%), solicited (58.8%), and local (61.8%); 69.4% with causal association with vaccination. Serious adverse events were not found. The FINLAY-FR-1 group reported more subjects with adverse events than the other two groups. After the third dose, anti-RBD seroconversion was 100%, 94.4% and 90% for the FINLAY-FR-1, FINLAY-FR-1A-50 and FINLAY-FR-1A-25 respectively. The in-vitro inhibition of RBD:hACE2 interaction increased after the second dose in all formulations. The geometric mean neutralizing titres after the third dose rose significantly in the group vaccinated with FINLAY-FR-1 with respect to the other formulations and the COVID-19 Convalescent Serum Panel. No differences were found between FINLAY-FR-1 homologous or heterologous schedules. CONCLUSIONS: Vaccine candidates were safe and immunogenic, and induced live-virus neutralizing antibodies against SARS-CoV-2. The highest values were obtained when outer membrane vesicles were used as adjuvant. TRIAL REGISTRY: https://rpcec.sld.cu/en/trials/RPCEC00000338-En.

Comparison of immune responses induced by two or three doses of an alum-adjuvanted inactivated SARS-CoV-2 vaccine in mice.

Waning antibodies and rapidly emerging variants are challenges for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine development. Adjusting existing immunization schedules and further boosting strategies are under consideration. Here, the immune responses induced by an alum-adjuvanted inactivated SARS-CoV-2 vaccine in mice were compared among immunization schedules with two or three doses. For the two-dose schedule, a 0-28-day schedule induced 5-fold stronger spike-specific IgG responses than a 0-14-day schedule, with only a slight elevation of spike-specific cellular immunity 14 days after the last immunization. A third homologous boost 2 or 5 months after the second dose for the 0-28-day schedule slightly strengthened humoral responses (1.3-fold for the 0-1-3-month schedule, and 1.8-fold for the 0-1-6-month schedule) 14 days after the last immunization. Additionally, a third homologous boost (especially with the 0-1-3-month schedule) induced significantly stronger cell-mediated immunity than both two-dose immunization schedules for all indexes tested, with a response similar to that induced by a one-dose heterologous boost with BNT162b2 in clinical trials, according to cellular immunity analysis (1.5-fold). These T cell responses were Th2 oriented, with good CD4+ and CD8+ memory. These results may offer clues for applying a homologous boosting strategy for alum-adjuvanted inactivated SARS-CoV-2 vaccines.

One or two doses of hepatitis A vaccine in universal vaccination programs in children in 2020: A systematic review.

BACKGROUND: Hepatitis A virus (HAV) is a global health concern as outbreaks continue to occur. Since 1999, several countries have introduced universal vaccination (UV) of children against HAV according to approved two-dose schedules. Other countries have implemented one-dose UV programs since 2005; the long-term impact of this schedule is not yet known. METHODS: We conducted a systematic literature search in four electronic databases for data published between January 2000 and July 2019 to assess evidence for one-dose and two-dose UV of children with non-live HAV vaccines and describe their global impact on incidence, mortality, and severity of hepatitis A, vaccine effectiveness, vaccine efficacy, and antibody persistence. RESULTS: Of 3739 records screened, 33 peer-reviewed articles and one conference abstract were included. Rapid declines in incidence of hepatitis A and related outcomes were observed in all age groups post-introduction of UV programs, which persisted for at least 14 years for two-dose and six years for one-dose programs according to respective study durations. Vaccine effectiveness was ≥95% over 3-5 years for two-dose programs. Vaccine efficacy was >98% over 0.1-7.5 years for one-dose vaccination. Antibody persistence in vaccinated individuals was documented for up to 15 years (≥90%) and ten years (≥74%) for two-dose and one-dose schedules, respectively. CONCLUSION: Experience with two-dose UV of children against HAV is extensive, demonstrating an impact on the incidence of hepatitis A and antibody persistence for at least 15 years in many countries globally. Because evidence is more limited for one-dose UV, we were unable to draw conclusions on immune response persistence beyond ten years or the need for booster doses later in life. Ongoing epidemiological monitoring is essential in countries implementing one-dose UV against HAV. Based on current evidence, two doses of non-live HAV vaccines are needed to ensure long-term protection.

The recommended lifetime immunization schedule from the board of vaccination calendar for life in Italy: A continuing example of impact on public health policies.

The Vaccination Calendar for Life is an alliance of scientific and professional societies of public health physicians, paediatricians and general practitioners in Italy which provides a periodical update on the ideal, scientifically driven vaccination calendar throughout lifetime. Since 2012, the Lifetime Immunization Schedule has represented a benchmark for Regional and National Authorities to set up the updated list of vaccines provided actively and free of charge to infants, children, adolescents, adults and the elderly by inclusion in the Triennial National Vaccination Plan (TNVP), and in the Essential Levels of Care (LEA). The impact of the different editions of the Lifetime Immunization Schedule on the TNVP was deep, representing the inspiring source for the present vaccination policy. The 2019 edition called for more attention to pregnant women immunization; risk groups vaccination; uniform high coverage with the MMRV vaccine; extension of Meningococcal B vaccination also at adolescent age; use of quadrivalent conjugate meningococcal vaccine also at 1 year of life; progressive decrease of the age of free-of-charge offer of influenza to ≥ 60 and then to ≥ 50 year-old population; implementation of flu immunization ages 6 months-6 years; HPV vaccination also offered to 25-year old women at the time of the first screening (gender neutral immunization already offered); sequential PCV13-PPV23 pneumococcal vaccination in 65 year-old subjects; increased coverage with rotavirus vaccine in infants and zoster vaccine in the elderly.

Clinical Decision Support for Immunization Uptake and Use in Immunization Health Information Systems.

CONTEXT: In the United States, immunization recommendations and their associated schedules are developed by the Advisory Committee on Immunization Practices (ACIP). To assist with the translation process and better harmonize the outcomes of existing clinical decision support tools, the Centers for Disease Control and Prevention (CDC) created clinical decision support for immunization (CDSi) resources for each set of ACIP recommendations. These resources are continually updated and refined as new vaccine recommendations and clarifications become available and will be available to health information systems for a coronavirus disease 2019 (COVID-19) vaccine when one becomes available for use in the United States Objectives: To assess awareness of CDSi resources, whether CDSi resources were being used by immunization-related health information systems, and perceived impact of CDSi resources on stakeholders' work Design: Online surveys conducted from 2015-2019 including qualitative and quantitative questions Participants: The main and technical contact from each of the 64 CDC-funded immunization information system (IIS) awardees, IIS vendors, and electronic health record vendors Results: Awareness of at least one resource increased from 75% of respondents in 2015 to 100% in 2019. Use of at least one CDSi resource also increased from 47% in 2015 to 78% in 2019. About 80% or more of users of CDSi are somewhat or very highly satisfied with the resources and report a somewhat or very positive impact from using them Conclusion: As awareness and use of CDSi resources increases, the likelihood that patients receive recommended immunizations at the right time will also increase. Rapid and precise integration of vaccine recommendations into health information systems will be particularly important when a COVID-19 vaccine becomes available to help facilitate vaccine implementation.