Timely uptake of the second dose of measles vaccine and associated factors among eligible children in Shinyanga District, Tanzania

Abstract

Background: Timely uptake of vaccine is a key determinant to prevent unnecessary childhood mortality from vaccine-preventable diseases. Despite the substantial efforts that have done in our country to improve vaccination coverage, the effort towards timeliness of vaccination remains a big challenge, especially in second dose measles vaccine. For that case, children continue to be susceptible to measles, increased risk of outbreak and failure to eliminate measles within the community. There is also a limited evidence on timely uptake of second dose measles vaccine within our country. Therefore, this study aimed to determine the timeliness of second dose measles vaccine and its associated factors among children in eligible children in Shinyanga district. Objectives: To determine the timely uptake of second dose measles vaccine and its associated factors among eligible children in Shinyanga district, Tanzania. Materials and Methods: A community based quantitative cross-sectional study was conducted in six wards of Shinyanga District among 570 children aged 20-24 months at the time of data collection. Three stage Simple random sampling was used to select wards, households and to recruit participants. Timely uptake of measles vaccine was assessed by checking the vaccination date on immunization card and it was categorized as timely uptake or untimely uptake of second dose measles vaccine. A child was considered vaccinated on time (timely vaccinated) if a child received the vaccination within 1 month of the recommended age of vaccination (18th months). Caregivers were interviewed using questionnaire to obtain information of the child, caregiver and the determinants of timely uptake of MCV2. The data were entered, cleaned and analyzed using SPSS version 23. Proportions and Prevalence ratios were used to estimate the timely uptake and the association of timely uptake. Modified Poisson regression were used to identify factors independently associate with the timely uptake of MCV2. Results: Out of 570 children assessed, 400 (70.2%) were vaccinated on time with MCV2. Significant predictors of timely uptake of MCV2 were Child birth order (aPR 1.60; CI 1.22 – 2.13; P< 0.001), Delivering on the way to the hospital (aPR 1.12; CI 1.00 – 1.41; P= 0.049) Caregivers having high education (aPR 1.15; CI 1.01 – 1.31; P= 0.034), being unemployed (aPR 1.23; CI 1.05 – 1.43; P= 0.009), head of the household sex (aPR 1.15; 95% CI 1.02 – 1.31 P=0.025) and caregivers with high level of knowledge (aPR 1.34; CI 1.18 – 1.52; P< 0.001). Conclusion and Recommendations: Timely uptake of MCV2 in Shinyanga district is below the WHO recommended timeliness. Childhood factors and maternal factors were significantly associated with the delay uptake of MCV2. The proportion of those receive MCV2 on time is not sufficient to prevent outbreaks, to reduce the risk of measles transmission and to attain the herd immunity. Hence, there is a need to take measures to improve timely uptake of MCV2 urgently among the susceptible children. Additionally, timeliness should be incorporated into the official routine vaccination statistics which will be helpful in appraising the reported coverage of measles vaccination in Tanzania.