473Preventable pertussis burden in Australia within the first year of life by improving vaccination timeliness

Background Previous Australian studies have shown that on-time Diphtheria-Tetanus-Pertussis (DTP) vaccination coverage is 50-60% in certain subpopulations. We estimated the potentially preventable burden of pertussis if, 1) the full primary course and, 2) each dose was given on-time. Methods Perinatal, immunisation, pertussis notification, and death data were linked for 1,412,984 infants born in two Australian states in 2000-2012. A DTP dose administered >15 days after the recommended age was categorised as delayed. For aim 1, pertussis rates up to 1-year of age were compared in infants with ≥1 dose delayed versus all doses on-time, using Poisson regression methods. For aim 2, the expected number of cases preventable by each dose was calculated as the product of the number of cases observed during the period of delay and (1 – dose-specific vaccine effectiveness). Results 58% of infants had all primary DTP doses on time. We estimated that 85 (95% CI: 61-109) cases per 100,000 infants, aged 39-days to 1-year, could have been prevented if all infants had been vaccinated on time; 77% of these infants had received ≥1 DTP dose within the first year of life. Estimated preventable burden attributable to delayed DTP1 (58/100,000) was higher than for DTP2 (26/100,000) and DTP3 (15/100,000). Conclusions and Key messages Poor vaccine timeliness, especially delayed DTP1, is a key contributor to the residual burden of pertussis. These findings can inform cost-benefit analyses of targeted programs and public health messaging to reduce delays.

Tracking demographic movements and immunization status to improve children access to immunization (TDM-IAI): A Field-Based Randomized Controlled Trial (Preprint)

BACKGROUND Vaccines offered by countries’ expanded program on immunization contribute to the reduction of mortality and morbidity, but access to these vaccines remains quite limited in most developing countries. OBJECTIVE The present trial assesses whether involving Community Volunteers (CV) to track children vaccination status and demographic movements and using recorded data to plan catch-up immunization sessions can improve children vaccination timeliness, completeness and coverage. METHODS This was a randomized controlled field trial in which communities of the Foumban Health district based in West region of Cameroon were allocated to intervention or control groups. In the intervention group, a CV per community was trained to visit households monthly for a year to record EPI targeted children in a Community EPI register (CER), their demographic movements and assess their immunization status. CER recorded page was snapped and sent to health center immunization team through WhatsApp and used to plan and implement monthly community catch up immunization sessions. In the control group, the EPI immunization sessions were conducted as routinely. Surveys were conducted at 6 (midline) and 12 (end line) months from the beginning of the intervention in both study groups to assess and compare immunization timeliness, coverage and completeness. RESULTS Thirty-two clusters per study group of about 160 buildings were followed for a year. In each cluster, a sample of 30 building was selected and surveyed at midline and endline. Of 792 and 876 households (HH) targeted for surveys in midline and end line in the intervention groups, 98.0% and 99.5% were reached respectively whereas in the control group, 1296 and 722 HH were targeted and 72.3% and 70.2% reached in midline and endline surveys respectively. One year after the implementation of the intervention, the timeliness of BCG administration in the first month of life did not increase in the intervention group compared to the control group for the age groups 0-11 (adjOR = 1.1 (0.7-1.8)) and 0-59 months (AdjOR=1.1(0.9-1.4)); meanwhile the increase was significant for the first year BCG administration for the age group 0-23 months (adjusted (AdjOR= 1.5 (1.1-2.2)). The coverage of DPT-Hi+Hb3 (AdjOR= 2.0 (1.5-2.7)), DPT-Hi+Hb1(adjOR= 1.8 (1.4-2.4)) significantly increased in the intervention group compared to the control group in age groups 12-59 and 12-23 months. Specific (DPT-Hi+Hb1 to DPT-Hi+Hb3) (AdjOR= 1.9 (1.4-2.6)) and general (BCG to measles) (AdjOR=1.5 (1.1-2.1)) vaccine completeness increased significantly in the intervention group compared to the control group. CONCLUSIONS Results of the present trial support that involving Community Volunteers to track children vaccination status and demographic movements and using recorded data to plan catch-up immunization sessions improve children vaccination timeliness, completeness and coverage. If its consistency is verified in other contexts, this strategy should be adopted to improve access to vaccination for EPI target populations. CLINICALTRIAL Pan African Clinical Trials Registry ID: PACTR201808527428720; Approved and registered on the August 22, 2018.

Timeliness of routine childhood vaccination in low- and middle-income countries, 1978–2021: Protocol for a scoping review to map methodologic gaps and determinants

The literature on the timeliness of childhood vaccination (i.e. vaccination at the earliest appropriate age) in low-and middle-income countries has important measurement and methodological issues that may limit their usefulness and cross comparison. We aim to conduct a comprehensive scoping review to map the existing literature with a key focus on how the literature on vaccination timeliness has evolved, how it has been defined or measured, and what determinants have been explored in the period spanning the last four decades. This scoping review protocol was developed based on the guidance for scoping reviews from the Joanna Briggs Institute. We will include English and French language peer-reviewed publications and grey literature on the timeliness of routine childhood vaccination in low-and middle-income countries published between January 1978 through to 2021. A three-step search strategy that involves an initial search of two databases to refine the keywords, a full search of all included electronic databases, and screening of references of previous studies for relevant articles missing from our full search will be employed. The search will be conducted in five electronic databases: MEDLINE, EMBASE, Global Health, CINAHL and Web of Science. Google search will also be conducted to identify relevant grey literature on vaccination timeliness. All retrieved titles from the search will be imported into Endnote X9.3.3 (Clarivate Analytics) and deduplicated. Two reviewers will screen the titles, abstracts and full texts of publications for eligibility using Rayyan–the web based application for screening articles for systematic reviews. Using a tailored data extraction template, we will extract relevant information from eligible studies. The study team will analyse the extracted data using descriptive statistical methods and thematic analysis. The results will be presented using tables, while charts and maps will be used to aid the visualisation of the key findings and themes. The proposed review will generate evidence on key methodological gaps in the literature on timeliness of childhood vaccination. Such evidence would shape the direction of future research, and assist immunisation programme managers and country-level stakeholders to address the needs of their national immunisation system.

Vaccination timeliness and associated factors among children aged 12-23 months in northwest Ethiopia: community-based study

Background: vaccines are the most effective preventive and success of public health to control and eradicate serious childhood diseases. Timely childhood vaccination can help for children to develop antibody against vaccine preventable diseases. Evidences on childhood vaccination timeliness, however, there are limited in developing countries including Ethiopia. Therefore, this study was aimed at assessing vaccination timeliness and associated factors among children aged 12 to 23 months in Jabitehnan district, northwest Ethiopia.Methods: A community based cross-sectional study was conducted in Jabitehnan district from February to March 2020. A total of 548 children aged 12-23 months were included using multi-stage and simple random sampling technique. Binary logistic regression model was fitted to identify factors associated with vaccination timeliness. Adjusted odd ratio (AOR) with 95% CI and p-value less than 0.05 were used to declare statistically significant variables. Results: A total of 13.1% (95 % CI: 10.1-15.8) of children were received childhood vaccines in the recommended time interval. Higher level of maternal education (AOR: 2.73; 95% CI: 1.14-6.50), history of abortion (AOR: 3.45; 95%CI: 1.54-7.74), knowledge (AOR: 1.79; 95%CI: 1.10-3.18) and favorable attitude (AOR: 3.38; 95%CI: 1.83-6.24) were positively associated with vaccination timeliness. While home delivery (AOR: O.35; 95%CI: 0.18-0.68) and rural residence (AOR: 0.31; 95%CI: 0.14-0.65) were negatively associated. Conclusion: The overall childhood vaccination timeliness status was low in the study area. Children were received the first dose of vaccines within the recommended time relatively higher than the other doses/vaccines. Moreover, children were received measles vaccine earlier and BCG vaccine later than the acceptable time interval. Variables such as residence, maternal level of education, having history of abortion, place of delivery, knowledge and attitudes were affecting vaccination timeliness. Therefore, the policy planners and managers should give emphasis and incorporate vaccination timeliness in the childhood vaccination plan, and better to monitor and evaluate as one potential indicator to enhance the immune status of children. Health planners and managers should also improve women’s awareness to enhance their attitude towards childhood vaccination. Furthermore, it is better to promote institutional delivery service utilization to enhance childhood vaccination timeliness.

Tracking demographic movements and immunization status to improve children access to immunization (TDM-IAI): A cluster randomized controlled trial protocol. (Preprint)

BACKGROUND In Cameroon, the coverage, completeness, and timeliness of EPI vaccines administration in children have remained heterogeneous and below the national and districts targets in several districts. In an effort to solve this problem, many interventions have been tested but none has shown significant improvement of the situation. OBJECTIVE Test whether involving Community Volunteers to assess children's vaccination status and demographic movements and using recorded data to plan catch-up immunization sessions can improve children's vaccination timeliness, completeness, and coverage. METHODS This is a cluster randomized controlled trial which aims to test whether involving Community Volunteers to assess children vaccination status and demographic movements and using recorded data to plan catch-up immunization sessions can improve children vaccination timeliness, completeness and coverage. Communities of the Foumban Health district, West region of Cameroon will be selected and assigned to either intervention or control groups using a restricted randomization of 2. In the intervention group, one Community Volunteer per community will be trained to visit households and record EPI targeted children in a register, their demographic movements and assess at monthly base their immunization status monthly for a year. The information recorded will be snapped and sent to the competent health center immunization team through WhatsApp. These will be used to plan and implement monthly community catch up immunization sessions in collaboration with the community volunteer. In the control group, the routine immunization sessions will be conducted with health centers organizing either weekly vaccination sessions for communities situated not farther than 5 kilometers away from the health facility or monthly vaccination sessions in communities situated more than 5 kilometers away from the health center. Baseline, mid-term and end-line surveys will be conducted to assess and compare immunization coverage, timeliness and completeness. RESULTS Discussion: This trial is expecting to test an innovative approach to improving children’s immunization timeliness, completeness and coverage by tracking EPI targeted population vaccination status and denominator at household level and building collaboration between the community and health facilities vaccination teams to organize monthly community-based response vaccination sessions. CONCLUSIONS This intervention is expected to improve children sustainable access to EPI vaccination as it offers assessing and responding to their immunization needs at monthly basis using low cost local human resources. CLINICALTRIAL Pan African Clinical Trials Registry PACTR201808527428720. Prospectively registered 22 August 2018.