Comparing performance of year-round and campaign-mode influenza vaccination strategies among children aged 6-23 months in Kenya: 2019-2021.

INTRODUCTION: In 2016, the Kenya National Immunization Technical Advisory Group requested additional programmatic and cost effectiveness data to inform the choice of strategy for a national influenza vaccination program among children aged 6-23 months of age. In response, we conducted an influenza vaccine demonstration project to compare the performance of a year-round versus campaign-mode vaccination strategy. Findings from this demonstration project will help identify essential learning lessons for a national program. METHODS: We compared two vaccine delivery strategies: (i) a year-round vaccination strategy where influenza vaccines were administered throughout the year at health facilities. This strategy was implemented in Njoro sub-county in Nakuru (November 2019 to October 2021) and Jomvu sub-county in Mombasa (December 2019 to October 2021), (ii) a campaign-mode vaccination strategy where vaccines were available at health facilities over four months. This strategy was implemented in Nakuru North sub-county in Nakuru (June to September 2021) and Likoni sub-county in Mombasa (July to October 2021). We assessed differences in coverage, dropout rates, vaccine wastage, and operational needs. RESULTS: We observed similar performance between strategies in coverage of the first dose of influenza vaccine (year-round strategy 59.7 %, campaign strategy 63.2 %). The coverage obtained in the year-round sub-counties was similar (Njoro 57.4 %; Jomvu 63.1 %); however, more marked differences between campaign sub-counties were observed (Nakuru North 73.4 %; Likoni 55.2 %). The campaign-mode strategy exceeded the cold chain capacity of participating health facilities, requiring thrice monthly instead of once monthly deliveries, and was associated with a two-fold increase in workload compared to the year-round strategy (168 vaccines administered per day in the campaign strategy versus 83 vaccines administered per day in the year-round strategy). CONCLUSION: Although both strategies had similar coverage levels, the campaign-mode strategy was associated with considerable operational needs that could significantly impact the immunization program.

Costs of seasonal influenza vaccine delivery in a pediatric demonstration project for children aged 6-23 months - Nakuru and Mombasa Counties, Kenya, 2019-2021.

BACKGROUND: During November 2019-October 2021, a pediatric influenza vaccination demonstration project was conducted in four sub-counties in Kenya. The demonstration piloted two different delivery strategies: year-round vaccination and a four-month vaccination campaign. Our objective was to compare the costs of both delivery strategies. METHODS: Cost data were collected using standardized questionnaires and extracted from government and project accounting records. We reported total costs and costs per vaccine dose administered by delivery strategy from the Kenyan government perspective in 2021 US$. Costs were separated into financial costs (monetary expenditures) and economic costs (financial costs plus the value of existing resources). We also separated costs by administrative level (national, regional, county, sub-county, and health facility) and program activity (advocacy and social mobilization; training; distribution, storage, and waste management; service delivery; monitoring; and supervision). RESULTS: The total estimated cost of the pediatric influenza demonstration project was US$ 225,269 (financial) and US$ 326,691 (economic) for the year-round delivery strategy (30,397 vaccine doses administered), compared with US$ 214,753 (financial) and US$ 242,385 (economic) for the campaign strategy (25,404 doses administered). Vaccine purchase represented the largest proportion of costs for both strategies. Excluding vaccine purchase, the cost per dose administered was US$ 1.58 (financial) and US$ 5.84 (economic) for the year-round strategy and US$ 2.89 (financial) and US$ 4.56 (economic) for the campaign strategy. CONCLUSIONS: The financial cost per dose was 83% higher for the campaign strategy than the year-round strategy due to larger expenditures for advocacy and social mobilization, training, and hiring of surge staff for service delivery. However, the economic cost per dose was more comparable for both strategies (year-round 22% higher than campaign), balanced by higher costs of operating equipment and monitoring activities for the year-round strategy. These delivery cost data provide real-world evidence to inform pediatric influenza vaccine introduction in Kenya.

Resilience of routine childhood immunization services in two counties in Kenya in the face of the COVID-19 pandemic.

The recently emerged coronavirus disease 2019 (COVID-19) has caused considerable morbidity and mortality worldwide and disrupted health services. We describe the effect of the COVID-19 pandemic on utilization of childhood vaccination services during the pandemic. Using a mixed methods approach combining retrospective data review, a cross-sectional survey, focus group discussions among care givers and key informant interviews among nurses, we collected data between May and September 2021 in Mombasa and Nakuru counties. Overall, there was a <2 % decline in the number of vaccine doses administered during the pandemic period compared to the pre-pandemic period but this was statistically insignificant, both for the pentavalent-1 vaccine (ß = -0.013, p = 0.505) and the pentavalent-3 vaccine (ß = -0.012, p = 0.440). In government health facilities, there was 7.7 % reduction in the number of pentavalent-1 (ß = -0.08, p = 0.010) and 10.4 % reduction in the number of pentavalent-3 (ß = -0.11, p < 0.001) vaccine doses that were administered during the pandemic period. In non-government facilities, there was a 25.8 % increase in the number of pentavalent-1 (ß=0.23, p < 0.001) and 31.0 % increase in the number of pentavalent-3 (ß = -0.27, p < 0.001) vaccine doses that were administered facilities during the pandemic period. The strategies implemented to maintain immunization services during the pandemic period included providing messaging on the availability and importance of staying current with routine vaccination and conducting catch-up vaccinations and vaccination outreaches. Our findings suggest that the COVID-19 pandemic did not impact childhood vaccination services in Mombasa and Nakuru counties in Kenya. The private health facilities cushioned vaccination services against the effects of the pandemic and the strategies that were put in place by the ministry of health ensured continuation of vaccination services and encouraged uptake of the services during the pandemic period in the two counties in Kenya. These findings provide useful information to safeguard vaccination services during future pandemics.

Malaria vaccine coverage estimation using age-eligible populations and service user denominators in Kenya.

BACKGROUND: The World Health Organization approved the RTS,S/AS01 malaria vaccine for wider rollout, and Kenya participated in a phased pilot implementation from 2019 to understand its impact under routine conditions. Vaccine delivery requires coverage measures at national and sub-national levels to evaluate progress over time. This study aimed to estimate the coverage of the RTS,S/AS01 vaccine during the first 36 months of the Kenyan pilot implementation. METHODS: Monthly dose-specific immunization data for 23 sub-counties were obtained from routine health information systems at the facility level for 2019-2022. Coverage of each RTS,S/AS01 dose was determined using reported doses as a numerator and service-based (Penta 1 and Measles) or population (projected infant populations from WorldPop) as denominators. Descriptive statistics of vaccine delivery, dropout rates and coverage estimates were computed across the 36-month implementation period. RESULTS: Over 36 months, 818,648 RTSS/AS01 doses were administered. Facilities managed by the Ministry of Health and faith-based organizations accounted for over 88% of all vaccines delivered. Overall, service-based malaria vaccine coverage was 96%, 87%, 78%, and 39% for doses 1-4 respectively. Using a population-derived denominator for age-eligible children, vaccine coverage was 78%, 68%, 57%, and 24% for doses 1-4, respectively. Of the children that received measles dose 1 vaccines delivered at 9 months (coverage: 95%), 82% received RTSS/AS01 dose 3, only 66% of children who received measles dose 2 at 18 months (coverage: 59%) also received dose 4. CONCLUSION: The implementation programme successfully maintained high levels of coverage for the first three doses of RTSS/AS01 among children defined as EPI service users up to 9 months of age but had much lower coverage within the community with up to 1 in 5 children not receiving the vaccine. Consistent with vaccines delivered over the age of 1 year, coverage of the fourth malaria dose was low. Vaccine uptake, service access and dropout rates for malaria vaccines require constant monitoring and intervention to ensure maximum protection is conferred.

Impact, cost-effectiveness, and budget implications of HPV vaccination in Kenya: A modelling study.

BACKGROUND: Sub-Saharan Africa has the highest rate of cervical cancer cases and deaths worldwide. Kenya introduced a quadrivalent HPV vaccine (GARDASIL, hereafter referred to as GARDASIL-4) for ten-year-old girls in late 2019 with donor support from Gavi, the Vaccine Alliance. As Kenya may soon graduate from Gavi support, it is important to evaluate the potential cost-effectiveness and budget impact of the current HPV vaccine, and potential alternatives. METHODS: We used a proportionate outcomes static cohort model to evaluate the annual budget impact and lifetime cost-effectiveness of vaccinating ten-year-old girls over the period 2020-2029. We included a catch-up campaign for girls aged 11-14 years in 2020. We estimated cervical cancer cases, deaths, disability adjusted life years (DALYs), and healthcare costs (government and societal perspective) expected to occur with and without vaccination over the lifetimes of each cohort of vaccinated girls. For each of the four products available globally (CECOLIN©, CERVARIX©, GARDASIL-4©, and GARDASIL-9 ©), we estimated the cost (2021 US$) per DALY averted compared to no vaccine and to each other. Model inputs were obtained from published sources, as well as local stakeholders. RESULTS: We estimated 320,000 cases and 225,000 deaths attributed to cervical cancer over the lifetimes of the 14 evaluated birth cohorts. HPV vaccination could reduce this burden by 42-60 %. Without cross-protection, CECOLIN had the lowest net cost and most attractive cost-effectiveness. With cross-protection, CERVARIX was the most cost-effective. Under either scenario the most cost-effective vaccine had a 100 % probability of being cost-effective at a willingness-to-pay threshold of US$ 100 (5 % of Kenya's national gross domestic product per capita) compared to no vaccination. Should Kenya reach its target of 90 % coverage and graduate from Gavi support, the undiscounted annual vaccine program cost could exceed US$ 10 million per year. For all three vaccines currently supported by Gavi, a single-dose strategy would be cost-saving compared to no vaccination. CONCLUSION: HPV vaccination for girls is highly cost-effective in Kenya. Compared to GARDASIL-4, alternative products could provide similar or greater health benefits at lower net costs. Substantial government funding will be required to reach and sustain coverage targets as Kenya graduates from Gavi support. A single dose strategy is likely to have similar benefits for less cost.

Measles containing vaccine coverage and factors associated with its uptake among children aged 24-59 months in Cherangany Sub County, Trans Nzoia County, Kenya.

INTRODUCTION: Measles is a vaccine-preventable disease whose elimination depends on the measles-containing vaccine (MCV) coverage of ≥95% in the population. In 2020, Kenya reported 597 cases, an increase of 158 cases from those reported in 2019. This study aimed to estimate the measles vaccine coverage and factors associated with its uptake in Cherangany Sub County. METHODS: We conducted a cross-sectional study using cluster sampling in the Cherangany Sub County of Trans Nzoia County in May 2021. We enrolled eligible children aged between 24-59 months and interviewed their caregivers using a structured questionnaire. We conducted descriptive, bivariate, and multivariate analyses. We used Prevalence Odds Ratio (POR) at bivariate and adjusted POR (aPOR) at multivariate with their corresponding 95% confidence interval as the measure of association. We regarded the variables with a p-value of less <0.05 at the multivariate level as independently associated with immunization status. RESULTS: We recruited 536 eligible children. The median age of the participants was 39 months (Interquartile Range 31-50). The coverage was 96.6% (518/536) for MCV dose one (MCV 1), and 56.2% (301/536) MCV dose two (MCV 2). At the bivariate level, family monthly income (POR 2.32, 95% CI 1.14-4.72), child vaccination status for other scheduled vaccines (POR 0.21, 95% CI 0.07-0.66), caregiver's level of education (POR = 1.82, 95% CI 1.29-2.57), knowledge of the vaccine-preventable diseases (POR = 0.55, 95% CI 0.38-0.80), and knowledge of the number of MCV scheduled doses (POR = 0.13, 95% CI 0.09-0.02) were significantly associated with MCV uptake. The Caregiver's knowledge on the number of MCV scheduled doses (POR = 5.73, 95% CI 3.48-9.45) and children whose birth order was ≤5th born (POR = 0.5, 95% CI 0.22-0.95) were significantly associated with MCV uptake at the multivariate analysis. CONCLUSION: The MCV 2 coverage was lower than the WHO recommended ≥ 95%. Lack of knowledge of the number of MCV scheduled doses and the child's birth order in the family are factors associated with not being fully vaccinated against measles. RECOMMENDATION: There is a need to strengthen the defaulter tracing system to follow up the children who default after receiving MCV 1, focusing interventions on the identified factors.

Spatial access inequities and childhood immunisation uptake in Kenya.

BACKGROUND: Poor access to immunisation services remains a major barrier to achieving equity and expanding vaccination coverage in many sub-Saharan African countries. In Kenya, the extent to which spatial access affects immunisation coverage is not well understood. The aim of this study was to quantify spatial accessibility to immunising health facilities and determine its influence on immunisation uptake in Kenya while controlling for potential confounders. METHODS: Spatial databases of immunising facilities, road network, land use and elevation were used within a cost friction algorithim to estimate the travel time to immunising health facilities. Two travel scenarios were evaluated; (1) Walking only and (2) Optimistic scenario combining walking and motorized transport. Mean travel time to health facilities and proportions of the total population living within 1-h to the nearest immunising health facility were computed. Data from a nationally representative cross-sectional survey (KDHS 2014), was used to estimate the effect of mean travel time at survey cluster units for both fully immunised status and third dose of diphtheria-tetanus-pertussis (DPT3) vaccine using multi-level logistic regression models. RESULTS: Nationally, the mean travel time to immunising health facilities was 63 and 40 min using the walking and the optimistic travel scenarios respectively. Seventy five percent of the total population were within one-hour of walking to an immunising health facility while 93% were within one-hour considering the optimistic scenario. There were substantial variations across the country with 62%(29/47) and 34%(16/47) of the counties with < 90% of the population within one-hour from an immunising health facility using scenarios 1 and 2 respectively. Travel times > 1-h were significantly associated with low immunisation coverage in the univariate analysis for both fully immunised status and DPT3 vaccine. Children living more than 2-h were significantly less likely to be fully immunised [AOR:0.56(0.33-0.94) and receive DPT3 [AOR:0.51(0.21-0.92) after controlling for household wealth, mother's highest education level, parity and urban/rural residence. CONCLUSION: Travel time to immunising health facilities is a barrier to uptake of childhood vaccines in regions with suboptimal accessibility (> 2-h). Strategies that address access barriers in the hardest to reach communities are needed to enhance equitable access to immunisation services in Kenya.

Determinants of contraceptive use among postpartum women in a county hospital in rural KENYA.

BACKGROUND: There is a high unmet need for limiting and spacing child births during the postpartum period. Given the consequences of closely spaced births, and the benefits of longer pregnancy intervals, targeted activities are needed to reach this population of postpartum women. Our objective was to establish the determinants of contraceptive uptake among postpartum women in a county referral hospital in rural Kenya. METHODS: Sample was taken based on a mixed method approach that included both quantitative and qualitative methods of data collection. Postpartum women who had brought their children for the second dose of measles vaccine between 18 and 24 months were sampled Participants were interviewed using structured questionnaires, data was collected about their socio-demographic characteristics, fertility, knowledge, use, and access to contraceptives. Chi square tests were used to determine the relationship between uptake of postpartum family planning and: socio demographic characteristics, contraceptive knowledge, use access and fertility. Qualitative data collection included focus group discussions (FDGs) with mothers and in-depth interviews with service providers Information was obtained from mothers' regarding their perceptions on family planning methods, use, availability, access and barriers to uptake and key informants' views on family planning counseling practices and barriers to uptake of family planning RESULTS: More than three quarters (86.3%) of women used contraceptives within 1 year of delivery, with government facilities being the most common source. There was a significant association (p ≤ 0.05) between uptake of postpartum family planning and lower age, being married, higher education level, being employed and getting contraceptives at a health facility. One third of women expressing no intention of having additional children were not on contraceptives. In focus group discussions women perceived that the quality of services offered at the public facilities was relatively good because they felt that they were adequately counseled, as opposed to local chemist shops where they perceived the staff was not experienced. CONCLUSION: Contraceptive uptake was high among postpartum women, who desired to procure contraceptives at health facilities. However, there was unmet need for contraceptives among women who desired no more children. Government health facility stock outs represent a missed opportunity to get family planning methods, especially long acting reversible contraceptives, to postpartum women.