Related Experiment Video
Updated: May 23, 2025
Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
Published on: February 23, 2014
Associated factors for dropout of first versus third doses of pentavalent vaccination in Tanzania
Robert Tillya1, Gumi Abdallah1, Hajirani Msuya1
1Ifakara Health Institute, Dar es Salaam, Tanzania.
Insights
In Tanzania, a significant number of children miss the third dose of the pentavalent vaccine. Factors like caregiver wealth, sex, and education influence this dropout, highlighting the need for improved health education and targeted interventions.
Area of Science:
- Public Health
- Vaccinology
- Epidemiology
Background:
- Pentavalent vaccine protects against Diphtheria, Pertussis, Tetanus, Hepatitis B, and Haemophilus influenzae type B.
- Vaccination dropout is defined as not completing the third dose after receiving the first.
- Tanzania faces a gap between first-dose (97%) and third-dose (89%) pentavalent vaccine uptake.
Purpose of the Study:
- To investigate factors associated with pentavalent vaccine dropout (first- to third-dose) in Tanzania.
- To provide the first national-level analysis of these dropout factors.
- To inform strategies for improving routine immunization coverage.
Main Methods:
- A cross-sectional survey was conducted with 4403 caregivers of children aged 12-23 months in Tanzania.
- Randomly selected households were used for data collection.
- Caregiver interviews assessed routine immunization services and pentavalent vaccine uptake.
Main Results:
- The overall pentavalent vaccination dropout rate was 2.3%, with 91.5% receiving the first dose and 89.4% receiving the third dose.
- Dropout rates were higher in Tanzania Mainland (2.4%) compared to Zanzibar (0.9%).
- Caregiver's wealth quintile, sex, and education level were significantly associated with pentavalent-3 dropout.
Conclusions:
- Addressing socioeconomic factors and improving health education for expectant mothers can reduce pentavalent vaccine dropout.
- Targeted interventions at regional and district levels are crucial for optimizing vaccination coverage.
- Enhanced understanding of dropout determinants supports efforts to improve child health outcomes in Tanzania.
Abstract:
The pentavalent is a vaccine against Diphtheria, Pertussis, Tetanus, Hepatitis B, and Haemophilus type B influenza. A child is considered a pentavalent vaccination dropout if they have received the first dosage as advised but have not obtained the third dose. In Tanzania, the first-dose receiver of pentavalent was approximately 97 %, whereas only 89 % received a third dose. Unfortunately, no studies have been done in Tanzania to evaluate the factors at the national level that are linked with first-versus third-dose pentavalent vaccine dropout; hence, we explored these factors here for the first time. A cross-sectional survey of randomly selected households was conducted. The sample size was calculated to provide overall, age- and sex-specific coverage estimates for measles-rubella vaccine evaluation among children aged between 9 and 59 months at the national level, as explained elsewhere. The fieldwork activities were done for one month from November to December 2019 for both Zanzibar and Tanzania Mainland. A total of 4460 caregivers of children aged 12-23 months were interviewed for routine immunization services, and a total of 4403 caregivers were included in this analysis of the uptake of the pentavalent vaccine. The number of children who received the first dose of the pentavalent vaccine was 4020 (91.5 %), while the number of children who received the third dose of the pentavalent vaccine was 3915 (89.4 %). The overall pentavalent vaccination dropout rate was 2.3 %. The rate was lower in Zanzibar (0.9 %) than in the Tanzanian mainland (2.4 %). Wealth quintile, sex of caregivers, and education were factors significantly associated with the pentavalent-3 dropout rate among children aged 12-23 months in Tanzania. Our results provide strong support for further efforts to improve current vaccination coverage to optimize the use of prioritized, timely, and appropriate interventions at the regional and district levels and to improve the health education given to expectant women during their clinic visits so they may comprehend the value of routine immunization.
