COVID-19 pandemic impact on childhood vaccination coverage in Quebec, Canada

Childhood vaccination trends during 2019 to 2022 in Tanzania and the impact of the COVID-19 pandemic

The COVID-19 pandemic has significantly disrupted healthcare systems at all levels globally, notably affecting routine healthcare services, such as childhood vaccination. This study examined the impact of these disruptions on routine childhood vaccination programmes in Tanzania. We conducted a longitudinal study over four years in five Tanzanian regions: Mwanza, Dar es Salaam, Mtwara, Arusha, and Dodoma. This study analyzed the trends in the use of six essential vaccines: Bacille Calmette-Guérin (BCG), bivalent Oral Polio Vaccine (bOPV), Diphtheria Tetanus Pertussis, Hepatitis-B and Hib (DTP-HepB-Hib), measles-rubella (MR), Pneumococcal Conjugate Vaccine (PCV), and Rota vaccines. We evaluated annual and monthly vaccination trends using time-series and regression analyses. Predictive modeling was performed using an autoregressive integrated moving average (ARIMA) model. A total of 32,602,734 vaccination events were recorded across the regions from 2019 to 2022. Despite declining vaccination rates in 2020, there was a notable rebound in 2021, indicating the resilience of Tanzania's immunization program. The analysis also highlighted regional differences in vaccination rates when standardized per 1000 people. Seasonal fluctuations were observed in monthly vaccination rates, with BCG showing the most stable trend. Predictive modeling of BCG indicated stable and increasing vaccination coverage by 2023. These findings underscore the robustness of Tanzania's childhood immunization infrastructure in overcoming the challenges posed by the COVID-19 pandemic, as indicated by the strong recovery of vaccination rates post-2020. We provide valuable insights into the dynamics of vaccination during a global health crisis and highlight the importance of sustained immunization efforts to maintain public health.

"It's not that I don't trust vaccines, I just don't think I need them": Perspectives on COVID-19 vaccination

In Quebec (Canada), the roll-out of the vaccination started slowly in December 2020 due to limited vaccine supply. While the first and second doses were well-accepted among adults and vaccine uptake was above 90%, in late 2021 and 2022, vaccine acceptance decreased for children vaccination and receipt of a 3rd or a 4th dose. In the autumn of 2022, four focus groups were conducted with vaccine-hesitant parents of children aged 0-4 and adults who expressed little intention to receive a booster dose. The objective of this study was to gather participants' perspectives on vaccination in general, on the COVID-19 vaccination campaign and the information available, and to gain insights into the underlying reasons for their low intention of either having their child(ren) vaccinated, or receiving an additional dose of vaccine. A total of 35 participants took part in the focus groups. While participants expressed a certain level of trust and confidence in public health and government authorities regarding pandemic management and the vaccination campaign, they were also concerned that transparent information was lacking to support an informed decision on booster doses and children's vaccination. Many participants felt adequately protected against the infection during the focus groups, citing a lack of perceived benefits as the primary reason for refusing a booster dose. Parents who refused to administer the COVID-19 vaccine to their young children felt that the vaccine was not useful for children and were concerned about potential side effects. The majority reported that their opinions regarding other recommended vaccines had not changed since the beginning of the pandemic. While these results are reassuring, our findings highlight the importance of transparency in public health communications about vaccines to increase confidence and to develop strategies to address vaccine fatigue and complacency toward COVID-19 vaccines.

School-based vaccination program against HPV and Hepatitis B: A longitudinal analysis of vaccine coverage between 2015 and 2021 in Quebec

BACKGROUND

HPV vaccination prevents cancers, including 90% of cervical cancer. Since 2008, a school-based HPV vaccination program has been implemented in Quebec, but vaccine coverage is suboptimal. The COVID-19 pandemic disrupted school-based vaccination programs. This study aimed to assess variation in HPV vaccination coverage in the school-based program between 2015 and 2022 in Quebec and to identify sociodemographic characteristics associated with non-vaccination.

METHODS

HPV vaccine coverage data were extracted from the Quebec Immunization Registry for students in Grade 4 and matched to the 2016 Canadian census sociodemographic data. Descriptive analysis was conducted to explore individual-level vaccine coverage according to sociodemographic data. A Generalized Estimating Equations model assessed the independent association between non-vaccination and students' sociodemographic characteristics.

RESULTS

HPV vaccine coverage (at least one dose) was 84% in 2018-2019 and 85% in 2019-2020. A decrease was observed during the pandemic. In 2020-2021, the HPV vaccine coverage (at least one dose) was 52% (at the end of the school year) and rose to 84% with intense catch-up activities. In 2021-2022, the coverage was slightly lower than before the pandemic (81%). Factors in the dissemination area were statistically significantly associated with non-vaccination: material (p-value = 0.0001) and social deprivation index (p-value = 0.0048), the proportion of immigration (p-value < 0.0001), and the language spoken at home (English (p-value = 0.0318), other than French or English (p-value = 0.0001).

CONCLUSION

School-based vaccination programs offer equitable access to vaccination, and our analysis showed that some groups have consistently lower vaccine acceptance and uptake. Strategies to improve HPV vaccine coverage should target children living in areas with a higher proportion of immigrants, non-French speakers, and people from underprivileged backgrounds. Although it is too early to assess the full impact of COVID-19 on school-based programs in Quebec, it remains important to ensure that catch-up strategies are implemented for missed doses.

"Direct and indirect impacts of the COVID-19 pandemic on operational conduct of pediatric vaccine clinical trials"

The coronavirus 2019 (COVID-19) pandemic, as well as the resulting public health measures, impacted many aspects of society. The conduct of important pediatric vaccine trials was among these. Analyzing data from six ongoing non-COVID-19 pediatric vaccine trials we aimed to assess the operational impact of the COVID-19 pandemic using descriptive analyses. We identified multiple operational disruptions in trial conduct. Additionally, we identified higher percentages of missed routine vaccinations than investigational vaccines throughout the observation period. Overall, the impact of the COVID-19 pandemic was most apparent early in the pandemic period while adaptations to the pandemic were developed; however, some disruptions persisted throughout the observation period. Pediatric vaccine clinical trials are critical to developing new and/or improved vaccines for the pediatric population. Continued evaluation of the impacts of COVID-19 on pediatric vaccine clinical trials is warranted.

Routine childhood vaccination among ethnocultural groups in Canada during the COVID-19 pandemic: A national cross-sectional study

Some ethnocultural groups in Canada experience low routine childhood vaccination, with social locations and discriminations contributing to inequities. This study aimed to characterize routine childhood vaccination in the context of the COVID-19 pandemic, including the influence of discriminatory experiences when accessing health services. We conducted a cross-sectional national survey to assess parents' acceptance of routine vaccines for their children ≤ 17 years in Oct/Nov 2021. Descriptive statistics were used to explore differences among ethnocultural groups and logistic regression to assess associations with parents' low acceptance. Of 2531 parents, 21.8 % self-identified as Racialized minorities, 7.7 % Indigenous, 23.3 % newcomers, 10.0 % spoke minority languages most often, and 69.6 % belonged to a reference group who did not report these characteristics. Statistically significant findings included 36.6 % of Indigenous parents reporting that the pandemic made them realize that routine vaccines were more important compared to 16.7 % of newcomers. Discrimination/racism when accessing health services was most often experienced by Indigenous (27.8 %) and Racialized minorities (20.2 %), compared to the reference group (4.8 %). Racialized minorities were more likely to report low acceptance of routine vaccination (aOR = 2.19, 95 % CI: 1.18-4.05), and younger parents and those with only preschool-aged children were less likely to have low acceptance (aOR = 0.59, 95 % CI: 0.37-0.94; aOR = 0.53, 95 % CI: 0.36, 0.79). Low acceptance was associated with everyday stress preventing vaccination (aOR = 2.18, 95 % CI: 1.41-3.38). Public health decision-makers should ensure equitable access to routine childhood vaccination that targets the inclusion of ethnocultural groups, who may experience disproportionate barriers and low acceptance.

Effectiveness of a vaccine recovery plan after the COVID-19 pandemic in the Siracusa Local Health Authority, Italy. Results of one year follow-up

Introduction

The COVID-19 pandemic has strongly impacted on the immunization services around the world, threatening the gains made in the control of vaccine-preventable diseases.

Methods

A vaccination recovery plan of missed vaccinations has been put in place in the LHA of Siracusa after the pandemic. We compared 2021 and 2020 vaccination coverage by age group and vaccine type after one year of follow-up of the recovery plan. The Chi-square test was executed on proportions for the years 2021 vs 2020. Results were considered statistically significant at a two-tailed p-value ≤ 0.05.

Results

36-month coverage rates were 92.5% for polio and 93.7% for measles-containing-vaccine, representing -0.3% and -1.8% decreases, respectively, as compared to 2020. By 8 years of age (booster doses), immunisation coverage was 80.7% for polio and 80.1% for measles, representing a -5.7% and -3.7%, respectively, compared to 2020. 36-month coverage was 56.6% for Men B (-5.0% as compared to 2020), 73.2% for Men ACW135Y/C (+1.1% as compared to 2020) and 86.9% for PNC vaccine (-1.7%, as compared to 2020). Regarding HPV vaccination, in 2021, vaccine coverage was 44.2% (-4.4% compared to 2020). Compared to the previous report, the VC difference among the cohorts narrowed for all almost vaccinations, except for the anti-men B and the anti-HPV vaccination, for which we recorded an increase in VC difference, and for men ACW135Y/C, for which a significant increase has been recorded.

Conclusions

Despite the efforts to organize and realize an extensive and well-designed vaccination recovery, our data show that even after the 1-year follow-up, globally deficits in coverage for these routine vaccinations persist, although there has been a substantial and significant recovery of missed vaccinations, especially among younger children and for primary cycles.

Rotavirus A during the COVID-19 Pandemic in Brazil, 2020-2022: Emergence of G6P[8] Genotype

Rotavirus A (RVA) remains a leading cause of acute gastroenteritis (AGE) hospitalizations in children worldwide. During the COVID-19 pandemic, a reduction in vaccination coverage in Brazil and elsewhere was observed, and some reports have demonstrated a reduction in AGE notifications during the pandemic. This study aims to investigate the diversity and prevalence of RVA genotypes in children and adults presenting with AGE symptoms in Brazil during the COVID-19 pandemic between 2020 and 2022. RVA was screened using RT-qPCR; then, G and P genotypes were characterized using one-step multiplex RT-PCR. A total of 2173 samples were investigated over the three-year period, and we detected RVA in 7.7% of samples (n = 167), being 15.5% in 2020, 0.5% in 2021, and 13.8% in 2022. Higher RVA prevalence was observed in the Northeastern region (19.3%) compared to the Southeastern (6.1%) and Southern regions (5.5%). The most affected age group was children aged between 0 and 6 months old; however, this was not statistically significant. Genotyping and phylogenetic analysis identified the emergence of G6P[8] during the period; moreover, it was detected in 10.6% of samples in 2020 and in 83.5% in 2022. In contrast, the prevalence of G3P[8], the previous dominant genotype, decreased from 72.3% in 2020 to 11.3% in 2022. We also identified unusual strains, such as G3P[9] and G9P[4], being sporadically detected during the period. This is the first report on the molecular epidemiology and surveillance of RVA during the COVID-19 pandemic period in Brazil. Our study provides evidence for the importance of maintaining high and sustainable levels of vaccine coverage to protect against RVA disease. Furthermore, it highlights the need to maintain nationwide surveillance in order to monitor future trends and changes in the epidemiology of RVA in Brazil.

COVID-19 Impact on DTP Vaccination Trends in Africa: A Joinpoint Regression Analysis

BACKGROUND

Deaths due to vaccine-preventable diseases are one of the leading causes of death among African children. Vaccine coverage is an essential measure to decrease infant mortality. The COVID-19 pandemic has affected the healthcare system and may have disrupted vaccine coverage.

METHODS

DTP third doses (DTP3) Vaccine Coverage was extracted from UNICEF databases from 2012 to 2021 (the last available date). Joinpoint regression was performed to detect the point where the trend changed. The annual percentage change (APC) with 95% confidence intervals (95% CI) was calculated for Africa and the regions. We compared DTP3 vaccination coverage in 2019-2021 in each country using the Chi-square test.

RESULT

During the whole period, the vaccine coverage in Africa increased with an Annual Percent change of 1.2% (IC 95% 0.9-1.5): We detected one joinpoint in 2019. In 2019-2021, there was a decrease in DTP3 coverage with an APC of -3.5 (95% -6.0; -0,9). (p < 0.001). Vaccination rates decreased in many regions of Sub-Saharan Africa, especially in Eastern and Southern Africa. There were 26 countries (Angola, Cabo Verde, Comoros, Congo, Côte d'Ivoire, Democratic Republic of the Congo, Djibouti, Ethiopia, Eswatini, The Gambia, Guinea-Bissau, Liberia, Madagascar, Malawi, Mauritania, Mauritius, Mozambique, Rwanda, Senegal, Seychelles, Sierra Leone, Sudan, Tanzania, Togo, Tunisia, Uganda, and Zimbabwe) where the vaccine coverage during the two years decreased. There were 10 countries (Angola, Cabo Verde, Comoros, Democratic Republic of the Congo, Eswatini, The Gambia, Mozambique, Rwanda, Senegal, and Sudan) where the joinpoint regression detected a change in the trend.

CONCLUSIONS

COVID-19 has disrupted vaccine coverage, decreasing it all over Africa.

Vaccination against poliomyelitis in Brazil from 2011 to 2021: successes, setbacks, and challenges ahead

The drop in childhood vaccination coverage (VC), including poliomyelitis, has become a health concern. The objective was to analyze the temporal trend of coverage of the three doses of the polio vaccine in the first 12 months of life between 2011 and 2021, in addition to mapping vaccination coverage in Brazil, including the COVID-19 pandemic period. An ecological study was carried out using interrupted time series (STI) techniques and spatial analysis, with data from the National Immunization Program Information System. The VC trend was adjusted by the Newey-West variance estimator according to the federated units and the Brazilian Deprivation Index. The VC distribution was estimated by Bayesian models and the spatial clusters by the global and local Moran index, identifying areas of lower coverage in the health regions. There was a reduction in the VC over the period in all regions, being more pronounced in the North and Northeast regions and during the Covid-19 pandemic. The biggest drops were identified in states and health regions with greater social vulnerability after 2019. The drop in VC shows that the risk of reintroduction of the wild virus is imminent and the challenges need to be faced with the strengthening of the Brazilian Health System (SUS).

Vaccination against poliomyelitis in Brazil from 2011 to 2021: successes, setbacks, and challenges ahead

Abstract The drop in childhood vaccination coverage (VC), including poliomyelitis, has become a health concern. The objective was to analyze the temporal trend of coverage of the three doses of the polio vaccine in the first 12 months of life between 2011 and 2021, in addition to mapping vaccination coverage in Brazil, including the COVID-19 pandemic period. An ecological study was carried out using interrupted time series (STI) techniques and spatial analysis, with data from the National Immunization Program Information System. The VC trend was adjusted by the Newey-West variance estimator according to the federated units and the Brazilian Deprivation Index. The VC distribution was estimated by Bayesian models and the spatial clusters by the global and local Moran index, identifying areas of lower coverage in the health regions. There was a reduction in the VC over the period in all regions, being more pronounced in the North and Northeast regions and during the Covid-19 pandemic. The biggest drops were identified in states and health regions with greater social vulnerability after 2019. The drop in VC shows that the risk of reintroduction of the wild virus is imminent and the challenges need to be faced with the strengthening of the Brazilian Health System (SUS).

Change in Rotavirus Vaccine Coverage in Brazil from before (2015-2019) through the COVID-19 Pandemic Period (2020-2021)

During the COVID-19 pandemic, a reduction in vaccination coverage of children and adolescents was observed in several countries. The aim of this study was to assess the impact of the pandemic, in the first two years, on human rotavirus vaccine (HRV) coverage in Brazil compared with previous years. The number of doses of HRV administered in the period from January 2015 to December 2021 and its annual vaccination coverage were analyzed. The vaccination coverage decreased to 77.3% in 2020 and to 70.4% in 2021, substantially lower than the minimum that would be expected (89.2%); the decline was more pronounced in the second year of the pandemic despite the fact that in this period, the circulation restrictions were already less tight. Of the five Brazilian macro-regions, the northeast had the largest decline, and the south had the smallest impact on coverage. At the municipal level, less than half of the Brazilian municipalities managed to achieve vaccination coverage above 90% in either pandemic year. Although there was already a downward trend in coverage in the pre-pandemic years, the present study shows that the values recorded in 2020 and 2021 were significantly lower. Monitoring of vaccination coverage in the coming years should be carried out continuously in order to avoid a possible resurgence of rotavirus-induced diarrhea.

The impact of the COVID-19 pandemic on parents' perceptions and acceptance of routine childhood vaccination in Canada: A national longitudinal study

BACKGROUND

A decline in routine vaccination was reported by some countries early in the COVID-19 pandemic. In the context of the pandemic, determinants of routine childhood vaccination may have changed. Changes over time in parents' perceptions of routine vaccines and intentions for their children during the pandemic have not been fully explored. Understanding changes provides opportunities to promote routine childhood vaccines and address factors that may compromise parents' acceptance.

METHODS

We conducted longitudinal analysis of two sequential national surveys during the pandemic (Dec 2020 and Oct/Nov 2021) to assess changes over time in Canadian parents' perceptions of routine childhood vaccines, intentions to vaccinate, access for their children ≤ 17 years, and differences among sociodemographic characteristics. McNemar-Bowker tests were used to determine changes in parents' responses collected at two time points.

RESULTS

Of the 650 parents in the sample, 25.1% with a child ≤ 6 years and 20.5% with a child 7-17 years perceived that routine childhood vaccines were more important because of the pandemic. Between the two time points, parents' confidence in the safety (72.8% to 80.2%, p <.001) and effectiveness (81.7% to 85.2%, p =.007) of routine vaccines increased, parents were more engaged in vaccine decision-making (73.4% to 79.8%, p =.006), and everyday stress preventing vaccination decreased (78.8% to 68.5%, p <.001). Acceptance of routine vaccines increased (82.9% to 86.5%, p =.021), but more parents were undecided about influenza vaccination (12.6% to 20.3%, p =.002). Compared to parents with 1 child, those with 2 children reported increased vaccination acceptance (82.6% to 87.4%, p =.024).

INTERPRETATION

Under the spotlight of COVID-19, parents' confidence in routine vaccines, engagement in decision-making, and vaccination acceptance increased. Vaccination providers should support parents' decision-making as they navigate routine childhood vaccine uncertainties. Differences in parents' acceptance of routine and influenza vaccines for their children highlight the need for targeted communication strategies for specific vaccines.