Simulation based adaptive vaccine delivery strategy

Inoculation is one of the most common intervention methods to mitigate the number of incidents during an outbreak. It is a crucial point to decide which age or target groups in a society are priorly vaccinated. In this study, we considered this challenge and a late vaccine distribution scenario with a new vaccine delivery strategy. A given population is divided into five age groups with different contact and transmission rates. The proposed strategy distributes weekly shots to people in an age group or groups according to results of simulation modelling different vaccination strategies for a week time horizon by considering historical incident rates of the outbreak. The method is tested against the strategy of vaccinating schoolchildren considered in many related publications in the literature. According to results, for 20 scenarios based on different contact and transmission rates and under three coverage levels, our method outperforms the benchmark strategy under 20% and 30% coverage levels for each scenario. Both strategies mostly follow same distributions and come up with same results under 10% coverage level. We can conclude that the proposed method is robust to changes in contact and transmission rates and provides superior results when coverage levels are relatively high. The method can provide effective vaccination strategies by considering disease dynamics for primarily COVID-19 and future pandemics. (English) [ FROM AUTHOR] Aşılama, bir salgın sırasında oluşacak vaka sayısını azaltmak için kullanılan en yaygın müdahale yöntemlerinden biridir. Bir toplumda hangi yaş ve hedef gruplarının öncelikle aşılanacağına karar vermek çok önemli bir noktadır. Bu çalışmada hem bu nokta hem de geç aşı dağıtım senaryosu, yeni bir aşı dağıtma stratejisi ile düşünülmüştür. Íncelenen popülasyon farklı kontak ve bulaştırma oranları düşünülerek beş farklı gruba ayrılmıştır. Önerilen aşı dağıtma stratejisi, salgın sırasında oluşan vaka sayılarını da düşünerek, haftalık dağıtılabilecek aşıları farklı yaş gruplarında bulunan kişilere, bir hafta süre için farklı dağıtım stratejilerini modelleyen bir benzetimin sonuçlarına göre dağıtmaktadır. Bu metot, literatürdeki birçok çalışmada düşünülen okul çağındaki çocukları öncelikle aşılama stratejisine karşı test edilmiştir. Farklı kontak ve bulaştırma oranlarına göre oluşturulan 20 farklı senaryo ve 3 farklı kapsama seviyesi için elde edilen sonuçlara göre önerilen metot, %20 ve %30 kapsama seviyesi için karşılaştırılan stratejiden daha iyi sonuçlar vermiş, %10 kapsama seviyesi için de benzer sonuçlar gözlenmiştir. Sonuç olarak, kapsama seviyesinin göreceli daha yüksek olduğu durumlarda, önerilen metodun kontak ve bulaş oranlarında meydana gelen değişimlere karşı daha gürbüz olduğu ve daha iyi sonuçlar verdiği görülmüştür. Başta COVID-19 olmak üzere gelecekte yaşanabilecek salgınlarda, hastalık dinamiklerini de düşünerek, efektif aşı dağıtımlarını gerçekleştirebilecektir. (Turkish) [ FROM AUTHOR] Copyright of Journal of the Faculty of Engineering & Architecture of Gazi University / Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, is the property of Gazi University, Faculty of Engineering & Architecture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Simulation based adaptive vaccine delivery strategy.

Inoculation is one of the most common intervention methods to mitigate the number of incidents during an outbreak. It is a crucial point to decide which age or target groups in a society are priorly vaccinated. In this study, we considered this challenge and a late vaccine distribution scenario with a new vaccine delivery strategy. A given population is divided into five age groups with different contact and transmission rates. The proposed strategy distributes weekly shots to people in an age group or groups according to results of simulation modelling different vaccination strategies for a week time horizon by considering historical incident rates of the outbreak. The method is tested against the strategy of vaccinating schoolchildren considered in many related publications in the literature. According to results, for 20 scenarios based on different contact and transmission rates and under three coverage levels, our method outperforms the benchmark strategy under 20% and 30% coverage levels for each scenario. Both strategies mostly follow same distributions and come up with same results under 10% coverage level. We can conclude that the proposed method is robust to changes in contact and transmission rates and provides superior results when coverage levels are relatively high. The method can provide effective vaccination strategies by considering disease dynamics for primarily COVID-19 and future pandemics. (English) [ FROM AUTHOR] Aşılama, bir salgın sırasında oluşacak vaka sayısını azaltmak için kullanılan en yaygın müdahale yöntemlerinden biridir. Bir toplumda hangi yaş ve hedef gruplarının öncelikle aşılanacağına karar vermek çok önemli bir noktadır. Bu çalışmada hem bu nokta hem de geç aşı dağıtım senaryosu, yeni bir aşı dağıtma stratejisi ile düşünülmüştür. Íncelenen popülasyon farklı kontak ve bulaştırma oranları düşünülerek beş farklı gruba ayrılmıştır. Önerilen aşı dağıtma stratejisi, salgın sırasında oluşan vaka sayılarını da düşünerek, haftalık dağıtılabilecek aşıları farklı yaş gruplarında bulunan kişilere, bir hafta süre için farklı dağıtım stratejilerini modelleyen bir benzetimin sonuçlarına göre dağıtmaktadır. Bu metot, literatürdeki birçok çalışmada düşünülen okul çağındaki çocukları öncelikle aşılama stratejisine karşı test edilmiştir. Farklı kontak ve bulaştırma oranlarına göre oluşturulan 20 farklı senaryo ve 3 farklı kapsama seviyesi için elde edilen sonuçlara göre önerilen metot, %20 ve %30 kapsama seviyesi için karşılaştırılan stratejiden daha iyi sonuçlar vermiş, %10 kapsama seviyesi için de benzer sonuçlar gözlenmiştir. Sonuç olarak, kapsama seviyesinin göreceli daha yüksek olduğu durumlarda, önerilen metodun kontak ve bulaş oranlarında meydana gelen değişimlere karşı daha gürbüz olduğu ve daha iyi sonuçlar verdiği görülmüştür. Başta COVID-19 olmak üzere gelecekte yaşanabilecek salgınlarda, hastalık dinamiklerini de düşünerek, efektif aşı dağıtımlarını gerçekleştirebilecektir. (Turkish) [ FROM AUTHOR] Copyright of Journal of the Faculty of Engineering & Architecture of Gazi University / Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, is the property of Gazi University, Faculty of Engineering & Architecture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

The Role of Immunity in the Pathogenesis of SARS-CoV-2 Infection and in the Protection Generated by COVID-19 Vaccines in Different Age Groups.

This study aims to review the available data regarding the central role of immunity in combating SARS-CoV-2 infection and in the generation of protection by vaccination against COVID-19 in different age groups. Physiologically, the immune response and the components involved in it are variable, both functionally and quantitatively, in neonates, infants, children, adolescents, and adults. These immunological differences are mirrored during COVID-19 infection and in the post-vaccination period. The outcome of SARS-CoV-2 infection is greatly dependent on the reaction orchestrated by the immune system. This is clearly obvious in relation to the clinical status of COVID-19 infection, which can be symptomless, mild, moderate, or severe. Even the complications of the disease show a proportional pattern in relation to the immune response. On the contrary, the commonly used anti-COVID-19 vaccines generate protective humoral and cellular immunity. The magnitude of this immunity and the components involved in it are discussed in detail. Furthermore, many of the adverse effects of these vaccines can be explained on the basis of immune reactions against the different components of the vaccines. Regarding the appropriate choice of vaccine for different age groups, many factors have to be considered. This is a cornerstone, particularly in the following age groups: 1 day to 5 years, 6 to 11 years, and 12 to 17 years. Many factors are involved in deciding the route, doses, and schedule of vaccination for children. Another important issue in this dilemma is the hesitancy of families in making the decision about whether to vaccinate their children. Added to these difficulties is the choice by health authorities and governments concerning whether to make children's vaccination compulsory. In this respect, although rare and limited, adverse effects of vaccines in children have been detected, some of which, unfortunately, have been serious or even fatal. However, to achieve comprehensive control over COVID-19 in communities, both children and adults have to be vaccinated, as the former group represents a reservoir for viral transmission. The understanding of the various immunological mechanisms involved in SARS-CoV-2 infection and in the preparation and application of its vaccines has given the sciences a great opportunity to further deepen and expand immunological knowledge. This will hopefully be reflected positively on other diseases through gaining an immunological background that may aid in diagnosis and therapy. Humanity is still in continuous conflict with SARS-CoV-2 infection and will be for a while, but the future is expected to be in favor of the prevention and control of this disease.

Parents' perception of COVID-19 risk of infection and intention to vaccinate their children.

Background: Parent's perception of the COVID-19 vaccines is very important to protect themselves and their children and achieve maximum effect of vaccination programs. Objective: Evaluate the perception and attitude of parents towards COVID-19 risk of infection and intentions to vaccinate their children. Method: Cross-sectional study including 1032 participants who have children aged from 5 to 18 years using a structured questionnaire. Results: Overall, 65.0% of participants or their family members suffered from comorbidities that poses them at risk for COVID-19 infection such as hypertension (25.1%) and diabetes mellitus (16.1%). The prevalence of tobacco smoking in the studied families was 36.9%. Among participants, 40.6% had a family member with history of confirmed COVID-19 infection. Nearly one-half of studied parents (48.2%) reported COVID-19 as a serious infection and the majority were worried about getting a family member infected (86.8%). Among participants 62.0% of male parents and 57.8% of female parents agreed that vaccine information is reliable. Participants reporting safety of COVID-19 vaccination represented 45.3%. If vaccine is available, 40.1% of parents intended to vaccinate their children. The main factors associated with the willingness to vaccinate children were vaccine is not suitable for children under 18 years (OR = 11.508), concern about vaccination safety (OR = 8.678), doubts about reliability of vaccine information (OR = 7.811) and ability of vaccine to prevent infection (OR = 5.766). Conclusion: Our study provides a brief insight about how parents think about COVID-19 vaccines and acceptance to vaccinate their children.

Antecedentes: La percepción de los padres sobre las vacunas contra el COVID-19 es muy importante para protegerse a sí mismos y a sus hijos y lograr el máximo efecto de los programas de vacunación. Objetivo: Evaluar la percepción y actitud de los padres hacia el riesgo de infección por COVID-19 y las intenciones de vacunar a sus hijos. Método: Estudio transversal que incluyó a 1032 participantes que tenían hijos de 5 a 18 años mediante un cuestionario estructurado. Resultados: En general, el 65,0% de los participantes o sus familiares padecieron comorbilidades que los ponen en riesgo de infección por COVID-19, como hipertensión (25,1%) y diabetes mellitus (16,1%). La prevalencia de tabaquismo en las familias estudiadas fue del 36,9%. Entre los participantes, el 40,6% tenía un familiar con antecedentes de infección confirmada por COVID-19. Casi la mitad de los padres estudiados (48,2%) informaron que la COVID-19 era una infección grave y la mayoría estaba preocupada por la posibilidad de que un miembro de la familia se infectara (86,8%). Entre los participantes, el 62,0% de los padres varones y el 57,8% de las mujeres acordaron que la información sobre las vacunas es confiable. Los participantes que informaron sobre la seguridad de la vacunación contra la COVID-19 representaron el 45,3%. Si la vacuna está disponible, el 40,1% de los padres tenía la intención de vacunar a sus hijos. Los principales factores asociados al deseo de vacunar a los niños fueron la vacuna no apta para menores de 18 años (OR = 11.508), preocupación por la seguridad vacunal (OR = 8.678), dudas sobre la confiabilidad de la información vacunal (OR = 7.811) y capacidad de vacuna para prevenir la infección (OR = 5.766). Conclusión: Nuestro estudio proporciona una breve perspectiva sobre cómo piensan los padres sobre las vacunas contra el COVID-19 y la aceptación de vacunar a sus hijos.

Barriers and Facilitators of Romanian HPV (Human Papillomavirus) Vaccination.

BACKGROUND: Many countries had initial success with HPV vaccination campaigns worldwide. The HPV vaccine coverage during the COVID-19 pandemic dropped consistently. The aim of our research is to assess the barriers and facilitators of the current Romanian HPV vaccination campaign. METHODS: An analytical cross-sectional observational survey was conducted in the Romanian general population; a self-administered questionnaire was used. RESULTS: 1122 responders were interviewed; 666 (59.36%) were parents, and 67 (5.97%) HPV vaccinated themselves. A multinominal logistic regression carried out in the parents' category showed that women with university studies and informed from medical sources have greater chances to HPV vaccinate. Reticence regarding vaccination comes from the high cost of the vaccine and a lack of information. Only 118 (10.51%) vaccinated against HPV. From the logistic regression analysis, gender (ORa 0.461 = 95% CI: (0.196; 1.083)), geographic area of residence (ORa = 0.517; 95% CI: (0.331; 0.807)), and the inclusion of the HPV vaccine in the National Vaccination Program (ORa = 2.4; 95% CI: (1.361; 4.235)) were the factors found most associated with HPV vaccination. CONCLUSIONS: In the general population, the inclusion of HPV vaccination in the National Vaccination Program would be the most important facilitator of HPV vaccination in Romania. In parents that did not vaccinate their children, one important barrier to HPV vaccination was the high cost of the HPV vaccine and the lack of proper information. The acceptability of HPV vaccination in Romania is low; therefore, public health educational programs are needed.

Parents' Perception, Acceptance, and Hesitancy to Vaccinate Their Children against COVID-19: Results from a National Study in the UAE.

Introduction: COVID-19 is considered the greatest health disaster affecting humans during the 21st century, which urged the need to develop an effective vaccine to acquire enough immunity against the virus. The main challenge faced during the development of such vaccines was the insufficiency of time, which raised the question about the vaccine safety and efficacy, especially among children. Parents' and caregivers' thoughts and acceptance of administering the vaccine to their children are still debatable topics and are yet to be explored in the UAE. Aims: The study aims to exploit parent acceptance, perception, and hesitancy toward the COVID-19 vaccine administration for their children and the link with their choice of distance learning instead of face-to-face education in the UAE. Methodology: This study utilized a cross-sectional descriptive design. A sample of 1049 parents across all emirates were conveniently approached and surveyed using Google forms from June to September 2021. The participants responded to a semi-structured questionnaire pertaining to socio-demographic, educational, and other questions related to COVID-19 and its link with their beliefs in whether the vaccination of their children will help with resuming face-to-face learning. Results: Approximately 74% of the parents confirmed that their children who are 16 years old and above have received the vaccine, and 71% were willing to give the vaccine to their children aged above 5 years. Parents with children receiving online education and those with children where the online modality of learning negatively affected their academic achievement are more prone to administer the COVID-19 vaccine to their children above five years old. The results show a significant association between vaccination of children and the parental desire for resuming physical attendance in schools (p value < 0.001). Multivariate analysis showed that the highest acceptance rate was from parents with children of low academic achievement due to online learning modality during the pandemic. Conclusion: In the UAE, parents of young children have shown a positive attitude towards COVID-19 vaccination in belief that vaccines will reduce the risk of infection and assist in resuming normal lifestyles, such as going back physically to schools. The results reflect the public awareness and the hypervigilance regarding the COVID-19 pandemic in the UAE.

Breakthrough SARS-CoV-2 infections in double and triple vaccinated adults and single dose vaccine effectiveness among children in Autumn 2021 in England: REACT-1 study.

Background: Prevalence of SARS-CoV-2 infection with Delta variant was increasing in England in late summer 2021 among children aged 5 to 17 years, and adults who had received two vaccine doses. In September 2021, a third (booster) dose was offered to vaccinated adults aged 50 years and over, vulnerable adults and healthcare/care-home workers, and a single vaccine dose already offered to 16 and 17 year-olds was extended to children aged 12 to 15 years. Methods: SARS-CoV-2 community prevalence in England was available from self-administered throat and nose swabs using reverse transcriptase polymerase chain reaction (RT-PCR) in round 13 (24 June to 12 July 2021, N = 98,233), round 14 (9 to 27 September 2021, N = 100,527) and round 15 (19 October to 5 November 2021, N = 100,112) from the REACT-1 study randomised community surveys. Linking to National Health Service (NHS) vaccination data for consenting participants, we estimated vaccine effectiveness in children aged 12 to 17 years and compared swab-positivity rates in adults who received a third dose with those who received two doses. Findings: Weighted SARS-CoV-2 prevalence was 1.57% (1.48%, 1.66%) in round 15 compared with 0.83% (0.76%, 0.89%) in round 14, and the previously observed link between infections and hospitalisations and deaths had weakened. Vaccine effectiveness against infection in children aged 12 to 17 years was estimated (round 15) at 64.0% (50.9%, 70.6%) and 67.7% (53.8%, 77.5%) for symptomatic infections. Adults who received a third vaccine dose were less likely to test positive compared to those who received two doses, with adjusted OR of 0.36 (0.25, 0.53). Interpretation: Vaccination of children aged 12 to 17 years and third (booster) doses in adults were effective at reducing infection risk. High rates of vaccination, including booster doses, are a key part of the strategy to reduce infection rates in the community. Funding: Department of Health and Social Care, England.

Parental COVID-19 Vaccine Hesitancy for Children in Romania: National Survey.

PURPOSE: Once vaccination against COVID-19 was also possible for children over 12 years of age, parents/legal guardians had to give their consent for their vaccination. It is a crucial moment, given the large number of infected people in Romania and the fact that these children are a source of transmission of the virus in the community. The refusal or hesitation of the parents/legal guardians, regarding the agreement for the vaccination of the children, determined us to focus on this subject, wishing, based on the questioning of as many parents as possible, to extract the reasons underlying these decisions. METHODS: This study is designed to observe the attitudes of parents/legal guardians regarding the refusal, hesitation, or acceptance of vaccination of children. The persons targeted to answer the questionnaire had to meet three conditions: to be at least 21 years old, to have a stable residence in Romania, and to be parents/legal guardians of at least one child under 18 years of age. The questionnaire was applied online to a number of 581 parents/legal guardians, being structured to obtain socio-demographic data and other categories of data that allow us to analyze their views on vaccinating children. RESULTS: Sociological data resulting from the application of the questionnaire on 581 parents/legal guardians show that 183 (31.5%) adults and 140 (24.1%) children got infected with COVID-19. The total number of respondents shows that only 411 (70.7%) adults and 185 (31.8%) children are vaccinated. CONCLUSIONS: From the analysis of the data obtained through the questionnaire, following the application of the Kendall and Spearman statistical analysis tests, it is found that there is a strong link between participants' trust/distrust in "fake news" information and their decision to vaccinate their children.

Investigating the Influence of Vaccine Literacy, Vaccine Perception and Vaccine Hesitancy on Israeli Parents' Acceptance of the COVID-19 Vaccine for Their Children: A Cross-Sectional Study.

Vaccination is currently the most effective strategy for combating COVID-19. COVID-19 vaccines were introduced to the adult population in Israel in early December 2020 and have been available for children aged 12-15 since June 2021. Our study aimed at assessing the influence of vaccine literacy, perception, hesitancy, and behavior on Israeli parents' intentions to have their children vaccinated. Using an anonymous online questionnaire, we recruited 520 parents; 70.4% of the parents indicated that they would get their children vaccinated. The participants' COVID-19 vaccination status was the only socio-demographic factor significantly associated with COVID-19 vaccination acceptability (OR = 32.89; 95%CI = [13.11, 82.54]). The most common sources of information regarding the COVID-19 vaccine were health-care providers and the Internet. Parents who intend to vaccinate their children had higher mean levels of vaccine literacy (2.99 ± 0.47 vs. 3.07 ± 0.44 respectively, p = 0.06), more positive perception of the vaccine (mean scores of 2.26 ± 0.75 vs. 3.44 ± 0.68 respectively, p < 0.001), and lower perceived vaccine hesitancy (7.53 ± 2.37 vs. 4.68 ± 2.71 respectively, p < 0.001) than parents who do not intend to do so. Vaccine behavior was measured using the 5C model of psychological antecedents. All 5C components were significantly correlated with parents' willingness to vaccinate their children. Understanding of parents' willingness to have their children receive the COVID-19 vaccine and the barriers to and facilitators of the vaccination is crucial, as vaccination of children aged 5-11 has recently been approved by the FDA. Providing the population with reliable information regarding the COVID-19 vaccine is an important measure in the attempt to increase COVID-19 vaccine acceptance.

Parent's Perspective towards Child COVID-19 Vaccination: An Online Cross-Sectional Study in Mexico.

COVID-19 vaccination programs continue in child populations. Thus, parents' attitude towards COVID-19 vaccination of their children is crucial for these strategies to succeed. The present study derives from the application of an online COVID-19 Vaccine Acceptance & Hesitancy Questionnaire (COV-AHQ) in which we measure parent's hesitancy towards children's vaccination (section 4 of the COV-AHQ) and other significant factors. A logistic regression analysis with backward stepwise method was used to quantify the associations between factors and parent's hesitancy. According to the correlation analysis, the most representative factors predicting vaccine hesitancy/acceptance were positive attitude towards vaccination, parents believing that the COVID-19 vaccine will enhance the economic situation of the country, parents actively researching information, having the willingness to obtain the COVID-19 vaccine themselves, and the possibility of their children developing adverse effects. Our findings also showed that parents are highly interested in having their children vaccinated. Nonetheless, parents expressed high levels of concern involving their children in developing adverse effects from the vaccine. In addition, obtaining influenza immunization prompted interest in obtaining the COVID-19 vaccine, and younger-aged parents are much more concerned with having their children vaccinated. Therefore, in order to ensure successful vaccination programs, policymakers and health authorities should design strategies to gain confidence and provide security amongst the population, including giving continuous information about the benefits of vaccination and presenting the frequency of side effects to bring parents on board with vaccinating their children.

Predicting COVID-19 Vaccination Intention: The Determinants of Vaccine Hesitancy.

Do people want to be vaccinated against COVID-19? Herd immunity is dependent on individuals' willingness to be vaccinated since vaccination is not mandatory. Our main goal was to investigate people's intention to be vaccinated and their intentions to vaccinate their children. Moreover, we were interested in understanding the role of the personal characteristics, psychological factors, and the lockdown context on that decision. Therefore, we conducted an online survey during the lockdown in Portugal (15 January 2021 until 14 March 2021). Participants completed a socio-demographic questionnaire, questions about their intentions of being vaccinated, concerns about the vaccine, a COVID-19 attitudes and beliefs scale, a COVID-19 vaccine attitudes and beliefs scale, and the Domain-Specific Risk-Taking (DOSPERT) Scale. Our results showed that from the 649 participants, 63% of the participants reported being very likely to have the vaccine, while 60% reported being very likely to vaccinate their children. We conducted two linear regression models, explaining 65% of the variance for personal vaccination and 56% of the variance for children vaccination. We found that the COVID-19 vaccine general beliefs and attitudes were the main determinants of vaccination intention. Additionally, our proposed artificial neural network model was able to predict with 85% accuracy vaccination intention. Thus, our results suggest that psychological factors are an essential determinant of vaccination intention. Thus, public policy decision makers may use these insights for predicting vaccine hesitancy and designing effective vaccination communication strategies.