Interventions for improving coverage of childhood immunisation in low- and middle-income countries

BACKGROUND

Immunisation plays a major role in reducing childhood morbidity and mortality. Getting children immunised against potentially fatal and debilitating vaccine-preventable diseases remains a challenge despite the availability of efficacious vaccines, particularly in low- and middle-income countries. With the introduction of new vaccines, this becomes increasingly difficult. There is therefore a current need to synthesise the available evidence on the strategies used to bridge this gap. This is a second update of the Cochrane Review first published in 2011 and updated in 2016, and it focuses on interventions for improving childhood immunisation coverage in low- and middle-income countries.

OBJECTIVES

To evaluate the effectiveness of intervention strategies to boost demand and supply of childhood vaccines, and sustain high childhood immunisation coverage in low- and middle-income countries.

SEARCH METHODS

We searched CENTRAL, MEDLINE, CINAHL, and Global Index Medicus (11 July 2022). We searched Embase, LILACS, and Sociological Abstracts (2 September 2014). We searched WHO ICTRP and ClinicalTrials.gov (11 July 2022). In addition, we screened reference lists of relevant systematic reviews for potentially eligible studies, and carried out a citation search for 14 of the included studies (19 February 2020).

SELECTION CRITERIA

Eligible studies were randomised controlled trials (RCTs), non-randomised RCTs (nRCTs), controlled before-after studies, and interrupted time series conducted in low- and middle-income countries involving children that were under five years of age, caregivers, and healthcare providers.

DATA COLLECTION AND ANALYSIS

We independently screened the search output, reviewed full texts of potentially eligible articles, assessed the risk of bias, and extracted data in duplicate, resolving discrepancies by consensus. We conducted random-effects meta-analyses and used GRADE to assess the certainty of the evidence.

MAIN RESULTS

Forty-one studies involving 100,747 participants are included in the review. Twenty studies were cluster-randomised and 15 studies were individually randomised controlled trials. Six studies were quasi-randomised. The studies were conducted in four upper-middle-income countries (China, Georgia, Mexico, Guatemala), 11 lower-middle-income countries (Côte d'Ivoire, Ghana, Honduras, India, Indonesia, Kenya, Nigeria, Nepal, Nicaragua, Pakistan, Zimbabwe), and three lower-income countries (Afghanistan, Mali, Rwanda). The interventions evaluated in the studies were health education (seven studies), patient reminders (13 studies), digital register (two studies), household incentives (three studies), regular immunisation outreach sessions (two studies), home visits (one study), supportive supervision (two studies), integration of immunisation services with intermittent preventive treatment of malaria (one study), payment for performance (two studies), engagement of community leaders (one study), training on interpersonal communication skills (one study), and logistic support to health facilities (one study). We judged nine of the included studies to have low risk of bias; the risk of bias in eight studies was unclear and 24 studies had high risk of bias. We found low-certainty evidence that health education (risk ratio (RR) 1.36, 95% confidence interval (CI) 1.15 to 1.62; 6 studies, 4375 participants) and home-based records (RR 1.36, 95% CI 1.06 to 1.75; 3 studies, 4019 participants) may improve coverage with DTP3/Penta 3 vaccine. Phone calls/short messages may have little or no effect on DTP3/Penta 3 vaccine uptake (RR 1.12, 95% CI 1.00 to 1.25; 6 studies, 3869 participants; low-certainty evidence); wearable reminders probably have little or no effect on DTP3/Penta 3 uptake (RR 1.02, 95% CI 0.97 to 1.07; 2 studies, 1567 participants; moderate-certainty evidence). Use of community leaders in combination with provider intervention probably increases the uptake of DTP3/Penta 3 vaccine (RR 1.37, 95% CI 1.11 to 1.69; 1 study, 2020 participants; moderate-certainty evidence). We are uncertain about the effect of immunisation outreach on DTP3/Penta 3 vaccine uptake in children under two years of age (RR 1.32, 95% CI 1.11 to 1.56; 1 study, 541 participants; very low-certainty evidence). We are also uncertain about the following interventions improving full vaccination of children under two years of age: training of health providers on interpersonal communication skills (RR 5.65, 95% CI 3.62 to 8.83; 1 study, 420 participants; very low-certainty evidence), and home visits (RR 1.29, 95% CI 1.15 to 1.45; 1 study, 419 participants; very low-certainty evidence). The same applies to the effect of training of health providers on interpersonal communication skills on the uptake of DTP3/Penta 3 by one year of age (very low-certainty evidence). The integration of immunisation with other services may, however, improve full vaccination (RR 1.29, 95% CI 1.16 to 1.44; 1 study, 1700 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Health education, home-based records, a combination of involvement of community leaders with health provider intervention, and integration of immunisation services may improve vaccine uptake. The certainty of the evidence for the included interventions ranged from moderate to very low. Low certainty of the evidence implies that the true effect of the interventions might be markedly different from the estimated effect. Further, more rigorous RCTs are, therefore, required to generate high-certainty evidence to inform policy and practice.

Exploring the factors contributing to low vaccination uptake for nationally recommended routine childhood and adolescent vaccines in Kenya

BACKGROUND

Vaccination remains the most effective means of reducing the burden of infectious disease among children. It is estimated to prevent between two to three million child deaths annually. However, despite being a successful intervention, basic vaccination coverage remains below the target. About 20 million infants are either under or not fully vaccinated, most of whom are in Sub-Saharan Africa region. In Kenya, the coverage is even lower at 83% than the global average of 86%. The objective of this study is to explore the factors that contribute to low demand or vaccine hesitancy for childhood and adolescent vaccines in Kenya.

METHODS

The study used qualitative research design. Key Informant Interviews (KII) was used to obtain information from national and county-level key stakeholders. In-depth Interviews (IDI) was done to collect opinions of caregivers of children 0-23 months and adolescent girls eligible for immunization, and Human papillomavirus (HPV) vaccine respectively. The data was collected at the national level and counties such as Kilifi, Turkana, Nairobi and Kitui. The data was analyzed using thematic content approach. A total of 41 national and county-level immunization officials and caregivers formed the sample.

RESULTS

Insufficient knowledge about vaccines, vaccine supply issues, frequent healthcare worker's industrial action, poverty, religious beliefs, inadequate vaccination campaigns, distance to vaccination centers, were identified as factors driving low demand or vaccine hesitancy against routine childhood immunization. While factors driving low uptake of the newly introduced HPV vaccine were reported to include misinformation about the vaccine, rumors that the vaccine is a form of female contraception, the suspicion that the vaccine is free and available only to girls, poor knowledge of cervical cancer and benefits of HPV vaccine.

CONCLUSIONS

Rural community sensitization on both routine childhood immunization and HPV vaccine should be key activities post COVID-19 pandemic. Likewise, the use of mainstream and social media outreaches, and vaccine champions could help reduce vaccine hesitancy. The findings are invaluable for informing design of context-specific interventions by national and county-level immunization stakeholders. Further studies on the relationship between attitude towards new vaccines and connection to vaccine hesitancy is necessary.

Interventions to increase COVID-19 vaccine uptake: a scoping review

BACKGROUND

Vaccines are effective in preventing severe COVID-19, a disease for which few treatments are available and which can lead to disability or death. Widespread vaccination against COVID-19 may help protect those not yet able to get vaccinated. In addition, new and vaccine-resistant mutations of SARS-CoV-2 may be less likely to develop if the spread of COVID-19 is limited. Different vaccines are now widely available in many settings. However, vaccine hesitancy is a serious threat to the goal of nationwide vaccination in many countries and poses a substantial threat to population health. This scoping review maps interventions aimed at increasing COVID-19 vaccine uptake and decreasing COVID-19 vaccine hesitancy.

OBJECTIVES

To scope the existing research landscape on interventions to enhance the willingness of different populations to be vaccinated against COVID-19, increase COVID-19 vaccine uptake, or decrease COVID-19 vaccine hesitancy, and to map the evidence according to addressed populations and intervention categories.

SEARCH METHODS

We searched Cochrane COVID-19 Study Register, Web of Science (Science Citation Index Expanded and Emerging Sources Citation Index), WHO COVID-19 Global literature on coronavirus disease, PsycINFO, and CINAHL to 11 October 2021.

SELECTION CRITERIA

We included studies that assess the impact of interventions implemented to enhance the willingness of different populations to be vaccinated against COVID-19, increase vaccine uptake, or decrease COVID-19 vaccine hesitancy. We included randomised controlled trials (RCTs), non-randomised studies of intervention (NRSIs), observational studies and case studies with more than 100 participants. Furthermore, we included systematic reviews and meta-analyses. We did not limit the scope of the review to a specific population or to specific outcomes assessed. We excluded interventions addressing hesitancy towards vaccines for diseases other than COVID-19.

DATA COLLECTION AND ANALYSIS

Data were analysed according to a protocol uploaded to the Open Science Framework. We used an interactive scoping map to visualise the results of our scoping review. We mapped the identified interventions according to pre-specified intervention categories, that were adapted to better fit the evidence. The intervention categories were: communication interventions, policy interventions, educational interventions, incentives (both financial and non-financial), interventions to improve access, and multidimensional interventions. The study outcomes were also included in the mapping. Furthermore, we mapped the country in which the study was conducted, the addressed population, and whether the design was randomised-controlled or not.

MAIN RESULTS

We included 96 studies in the scoping review, 35 of which are ongoing and 61 studies with published results. We did not identify any relevant systematic reviews. For an overview, please see the interactive scoping map (https://tinyurl.com/2p9jmx24) STUDIES WITH PUBLISHED RESULTS Of the 61 studies with published results, 46 studies were RCTs and 15 NRSIs. The interventions investigated in the studies were heterogeneous with most studies testing communication strategies to enhance COVID-19 vaccine uptake. Most studies assessed the willingness to get vaccinated as an outcome. The majority of studies were conducted in English-speaking high-income countries. Moreover, most studies investigated digital interventions in an online setting. Populations that were addressed were diverse. For example, studies targeted healthcare workers, ethnic minorities in the USA, students, soldiers, at-risk patients, or the general population.  ONGOING STUDIES Of the 35 ongoing studies, 29 studies are RCTs and six NRSIs. Educational and communication interventions were the most used types of interventions. The majority of ongoing studies plan to assess vaccine uptake as an outcome. Again, the majority of studies are being conducted in English-speaking high-income countries. In contrast to the studies with published results, most ongoing studies will not be conducted online. Addressed populations range from minority populations in the USA to healthcare workers or students. Eleven ongoing studies have estimated completion dates in 2022.   AUTHORS' CONCLUSIONS: We were able to identify and map a variety of heterogeneous interventions for increasing COVID-19 vaccine uptake or decreasing vaccine hesitancy. Our results demonstrate that this is an active field of research with 61 published studies and 35 studies still ongoing. This review gives a comprehensive overview of interventions to increase COVID-19 vaccine uptake and can be the foundation for subsequent systematic reviews on the effectiveness of interventions to increase COVID-19 vaccine uptake.  A research gap was shown for studies conducted in low and middle-income countries and studies investigating policy interventions and improved access, as well as for interventions addressing children and adolescents. As COVID-19 vaccines become more widely available, these populations and interventions should not be neglected in research.

AUTHORS CONCLUSIONS

We were able to identify and map a variety of heterogeneous interventions for increasing COVID-19 vaccine uptake or decreasing vaccine hesitancy. Our results demonstrate that this is an active field of research with 61 published studies and 35 studies still ongoing. This review gives a comprehensive overview of interventions to increase COVID-19 vaccine uptake and can be the foundation for subsequent systematic reviews on the effectiveness of interventions to increase COVID-19 vaccine uptake.  A research gap was shown for studies conducted in low and middle-income countries and studies investigating policy interventions and improved access, as well as for interventions addressing children and adolescents. As COVID-19 vaccines become more widely available, these populations and interventions should not be neglected in research.

Designing an SMS reminder intervention to improve vaccination uptake in Northern Nigeria: a qualitative study

BACKGROUND

Penta3 coverage in Nigeria was low at 33 % in 2017. The most reported reason for non-vaccination was lack of knowledge about the immunization place, time, and need. To address knowledge gaps and improve vaccination uptake, we designed an Immunization Reminder and Information SMS System (IRISS) to educate and remind parents/caregivers about immunization using SMS. A formative study was conducted to understand the contextual and behavioural factors that would inform the IRISS intervention design and implementation.

METHODS

We conducted the study in four Local Government Areas (LGAs) of Kebbi State Nigeria in October 2018, amongst a diverse selection of participants. Data on social norms about vaccinations, barriers to immunization uptake, mobile phone use, SMS message testing, and willingness to accept SMS reminders were collected from focus group discussions (N = 11), in-depth interviews (N = 12), and key informant interviews (N = 13). In addition, we assessed 33 messages covering schedule reminders, normative, motivational, educational, and informative contents for clarity, comprehensibility, relevance, cultural appropriateness, and ability to motivate action among community members from Argungu and Fakai LGAs. All interviews were analyzed using a thematic analysis approach.

RESULTS

We interviewed 135 people, and 90 % were community members. While we found positive perceptions about immunizations among those interviewed, pockets of misconceptions existed among community members. Lack of awareness on the importance of vaccination was a consistent reason for under-vaccination across the LGAs. In addition, most community members do not own phones, could not read SMS messages, and were unaware of how to check/open text messages received. Despite concerns about low literacy levels and phone ownership, community members still saw a role in SMS reminders when phone owners receive messages. For instance, community leaders can disseminate said messages to community members through existing channels such as town announcers and religious gatherings. Therefore, the SMS becomes a source of information, with phone owners acting as a conduit to community dissemination mechanisms. We generally found the tested messages to be relevant, motivating, and culturally acceptable.

CONCLUSIONS

SMS reminders have the potential to bridge the information gap in community awareness for vaccination, which can translate to improved immunization uptake. In rural communities with low literacy levels and phone ownership, immunization information can be disseminated when existing community leadership structures are engaged.

Reasons for non-vaccination and incomplete vaccinations among children in Pakistan

BACKGROUND

Global immunization efforts have received a boost through the introduction of several new vaccines. These efforts however, are threatened by sub-optimal vaccine coverage, particularly in countries with large birth cohorts. Pakistan has one of the largest birth cohorts in the world, where coverage of routine vaccination remains persistently inadequate. We undertook this study to ascertain reasons for non-vaccination or incomplete vaccination of children less than two years in 8 districts of southern Pakistan.

METHODS

A cross-sectional survey using WHO recommended rapid coverage assessment technique was conducted in 2014. Using probability proportional to size method, we sampled 8400 households with eligible children (aged 4-12 months). Using a structured questionnaire, mothers or other primary caregivers were interviewed to determine vaccination status of an index child. In case of non-vaccination or incomplete vaccination, respondents were asked for reasons leading to low/no vaccine uptake.

RESULTS

Based on both vaccination record and recall, only 30.8% of children were fully vaccinated, 46% had an incomplete vaccination status while 23%were non-vaccinated. The most frequently reported reasons for non-vaccination included: mothers/caregivers being unaware of the need for vaccination (35.3%), a fear of side effects (23%), mother/caregiver being too busy (16.6%), distance from vaccination centers (13.8%), and non-availability of either vaccinators or vaccines at vaccination centers (10.7%). Reasons identified for incomplete vaccination were similar, with caregivers being unaware of the need for subsequent doses (27.3%), non-availability of vaccinators or vaccines (17.7%), mother/caregiver being too busy (14.8%), fear of side effects (11.2%), and postponement for another time (8.7%).

CONCLUSION

Various factors result in non-compliance with vaccination schedules and vaccine refusal within the surveyed communities, ranging from lack of knowledge to non-availability of supplies at vaccination centers. These barriers are best addressed through multi-pronged strategies addressing supply gaps, increasing community awareness and enhancing demand for routine vaccination services.