https://orcid.org/0000-0003-3648-9891
ABSTRACT
Complete vaccination, meaning the administration of all doses in a vaccination regimen, is one of the most cost-effective interventions to reduce under-age-five-years mortality and morbidity. However, only a few studies have investigated the magnitude and predictors of incomplete vaccination. This study aimed to identify those factors associated with incomplete vaccination among children aged 12–23 months in Kutaber District, south Wollo zone, Ethiopia. A community-based cross-sectional study was conducted in Kutaber District from August to September 2017. A total of 480 participants were selected using the stratified multi-stage sampling technique. A structured, pre-tested and interviewer-administered questionnaire was used to collect the data. A logistic regression model was fitted to identify factors associated with incomplete vaccination. The prevalence of incomplete vaccination in this population was found to be 7.7%. The factors home delivery (Adjusted Odds Ratio (AOR) = 3.21), children from mothers with no history of Tetanus Toxoid (TT) vaccination (AOR = 5.26), living near the health post (AOR = 5.65), caregivers aged 19–26 years (AOR = 9.59), mothers/caregivers with no education (AOR = 3.71), and children from mothers with no Antenatal Care (ANC) follow-ups (AOR = 9.41) were found to be significantly associated with incomplete vaccination. The rate of incomplete vaccination was low as compared to the Ethiopian national report. Educational status of mother/caregiver, TT vaccination of mother, ANC follow-ups, place of delivery, and living near health facilities were significantly associated with incomplete vaccination. In light of these findings, the Ethiopian zonal health office and health care professionals should strengthen maternal health services to decrease the rate of defaulters from complete vaccination.
KEYWORDS:
Introduction
Complete vaccination of under five-children is one of the most cost-effective interventions in health care delivery.Citation1 Vaccination prevents illness, disability, and death from vaccine-preventable diseases, such as cervical cancer, diphtheria, hepatitis B, measles, mumps, pertussis (whooping cough), pneumonia, polio, rotavirus diarrhea, rubella and tetanus.Citation2 With vaccination, 2 to 3 million global deaths from diphtheria, measles and pertussis are avoided each year.Citation1 In Ethiopia, a child has to receive all basic vaccinations according to the World Health Organization (WHO) vaccination schedules, and take the vaccines like one dose of Bacillus Calmette-Guerin (BCG), the initial dose of oral polio vaccine (OPV0) given at birth, three doses of each Pentavalent (DPT‐HepB‐Hib), OPV, and Pneumococcal Conjugate Vaccine (PCV) given at the 6th, 10th and 14th weeks plus two doses of Rotavirus vaccine given at the 6th and 10th weeks and lastly measles vaccine at the 9th month.Citation3,Citation4
Although there was a high reduction in child mortality worldwide between 1990 and 2015, sub-Saharan Africa (SSA) was characterized by a high burden of under-five mortality with 83 deaths/1000 live births in 2015.Citation5 Ethiopia has been placed sixth among countries of the world in terms of child death as about 472,000 children die each year before their fifth birthday.Citation6 About 1.1 million global deaths of under five-children could be prevented through vaccination by new vaccines against pneumococcal disease and rotavirus diarrhea.Citation7
It is estimated that 22.6 million infants were partially vaccinated globally in 2013. One out of five infants doesn’t receive the 3 doses of tetanus, pertussis and diphtheria vaccines globally.Citation8 Most, (98%) of these have been living in developing countries, and roughly three million such children die every year from vaccine-preventable diseases (VPDs).Citation9,Citation10 Despite the fact that Africa has made remarkable progress in child vaccination, there are still a large number of unvaccinated and partially vaccinated children in the continent. According to the 2013 vaccination data report, Ethiopia ranked second next only to Nigeria on the list of countries with incompletely vaccinated children.Citation11,Citation12 The 2011 Ethiopian Demographic and Health Survey report showed only 24% of children aged 12–23 months were fully vaccinated.Citation13 A community-based survey conducted in 2016 showed a low full vaccination coverage of 22.9% in eastern, 27.7% in central, 41.7% in south and 51% in north Ethiopia.Citation14
Understanding factors that add to the rate of incomplete vaccination is essential to decrease the number of defaulters from vaccination. Several studies identified factors, like residence,Citation5 age of mother, birth order,Citation12,Citation15,Citation16 distance from health facility,Citation15,Citation17 educational status of mother,Citation16-Citation19 ANC visit,Citation5,Citation15,Citation20 place of deliveryCitation5,Citation18,Citation20,Citation21 and postnatal care(PNC) visitCitation20 to have an effect on incomplete vaccination.
Despite the implementation of outreach strategies, there is still a high rate of incomplete vaccination in Ethiopia. It is important to investigate and control the factors leading to incomplete vaccination to increase the rate of full vaccination coverage. Since studies on this issue are limited, we decided to assess the prevalence of incomplete vaccination and factors associated with it among children aged 12–23 months in Kutaber district, Ethiopia.
Materials and methods
A community-based cross-sectional study was conducted in Kutaber district, south Wollo zone, 422 km from Addis Ababa, the capital of Ethiopia from August 25 to September 25, 2017. All children aged 12–23 months in Kutaber district were the source and their mothers/caregivers study population. There were an estimated 14,294 under-five children and 3,249 of whom were under one year of age. A total of 480 participants were selected using the double population proportion formula assuming a proportion of incomplete vaccination in Tehuledere district northeast Ethiopia to be 16.9%,Citation22 confidence level 95%, margin of error 5%, design effect of 2 and 10% non-response rate.
Mothers/caregivers of children aged 12–23 months had urgent referrals, were unable to communicate and lived in the study area for less than six months were excluded.
A stratified multi-stage sampling technique was employed and the population was first stratified into urban and rural at first then, five (one urban and four rural) kebeles were selected using lottery method from a total of 21 (one urban and 20 rural) kebeles in the district. The calculated sample was proportionally allocated for the selected kebeles. Households with eligible children were selected through the systematic random sampling technique from the kebeles. The sample interval of the eligible households in each kebele was determined by dividing the total number of eligible households by the sample size. When there were two or more children in the same household, the younger one was selected; if there were twins, the lottery method was used to select one.
The dependent variable for this study was vaccination status (incomplete, complete). Vaccination was defined as incomplete when a child aged 12–23 months missed at least one dose of the nine routine vaccines within the 12 months of years.
The independent variables were socio-demographic and economic factors (age of mother/caregiver, sex of child, educational status, marital status, religion, residence and family size), maternal and child health service utilization (contraceptive use, ANC follow-up for the current child, place of delivery, and tetanus toxoid vaccination status of mothers/caretakers and parity), health service-related factors (accessibility, feasibility and quality of health service, time of travel to reach the nearest health facility, waiting time, hostility of health workers, health care environment, counseling), knowledge and attitude of caregivers to vaccination (knowledge of mothers/caregivers about vaccination schedule, benefit and side effects of vaccines and sessions needed to complete vaccination).
A structured, pre-tested and interview administered questionnaire was used to collect data. Eight diploma graduate nurses were recruited for data collection and supervision. The mother or caregiver was asked whether the child had a vaccination card. If she replied “yes”, she was requested to bring the vaccination card and data collectors checked the types of vaccines the child received according to the schedule. If the card gave such information, the vaccination status of the child was labeled as completely vaccinated, otherwise incompletely vaccinated. Additionally, photographing of vaccination cards and health facility registers were taken. If the mother or caregiver replied “no card”, other probing questions and techniques were considered to confirm the child was incompletely vaccinated or not.
Data were entered into Epi info version 7 and analyzed using SPSS version 20 after encoding. Descriptive analysis was carried out to describe the data, and binary logistic regression analysis was used to identify the independent significant predictors of incomplete vaccination.
An Adjusted Odds Ratio (AOR) with a 95% confidence interval was used to report the associations of variables. Independent variables significant at 0.25 in the bivariate analysis were entered and analyzed in the multivariable analysis. The cut of point 0.25 employed in the bivariate analysis was used to reduce the number of variables, not to test the association between variables, that can have a significant association in the multi-variable analysis. Hence, the independent variables might not be associated with dependent variable at a cut of point 0.25. The significance association in the multivariable analysis was declared at p-values of 0.05. The goodness of the model was assessed by the Hosmer and Lemeshow test.
The work was approved by the Ethical Review Committee of the University of Gondar, College of Medicine and Health Sciences. A written informed consent was also obtained from participants who were clearly informed that they had full rights to refuse or withdraw from the study. The privacy of participant information was protected, by not personal identifiers and keeping the questionnaire locked.
Results
Socio-demographic characteristics of caregivers
A total of 480 mothers/caregivers of children aged 12–23 months were surveyed. The mean age of the women was 30.9(±5.11SD) years and half; 211(49.8%) of them were in the age range of 27–34 years. Almost half; 239(49.8%) of the respondents had primary education. The majority, 375(78.1%), of the respondents were rural dwellers, and 376(78.3%) of the primary givers were both mothers and fathers ().
Table 1. Socio-demographic, obstetric and health facility related characteristics of mothers/caregivers in Kutaber district, northeast Ethiopia, 2017
Obstetric and health facility-related characteristics
More than half, 269(56%), of the children were male with a mean age of 16(±3.67SD) months. About one-third, 156(32.5%), of them were in the third birth order; the mean number of live births was 2.74 (±1.292). The majority, 465(96.87%), of the mothers received at least one antenatal care. About 436(90.8%) of them delivered their index children at health institutions ().
Incomplete vaccination among children aged 12–23 months
A total of 291(60.6%) of children had vaccination cards. The proportion of children incompletely vaccinated was 7.7% (95% CI: 0.056, 0.105). The problem by vaccination card was 10(5.29%) and 27(9.28%) among mothers/caregivers had no vaccination card and those had respectively. The reasons given for the incompleteness of vaccinations by 40.5, 27, 21.6, 18.9, 16.2 and 13.5% of the respondents were busyness, inability to remember the next appointment, lack of knowledge about the benefits of vaccination, bad information, child illness, absence of default tracing systems and lack of belief in vaccination, respectively.
Factors associated with incomplete vaccination
According to the multivariable logistic regression model, age and educational status of the mother/caregiver, TT vaccination of the mother, ANC follow-up, place of delivery and closeness of health facility were found to be independently associated with incomplete vaccination. The number of observations retained in the multi-variable analysis was 424.
Children born at home had 3.21 times higher odds of being incompletely vaccinated compared with children born at health institutions (95%CI: 1.12, 9.25). Children from a mother who had no history of TT vaccination had 5.26 times more odds of being incompletely vaccinated than to their counterparts (95%CI: 1.50, 18.43). Children living near a health post had 5.65 times increased odds of being incompletely vaccinated compared to children living near a health center or hospital (95% CI: 2.25, 14.24). Children whose mothers or caregivers were in the age group of 19–26 years had 9.56 times higher odds of being incompletely vaccinated than the 35 and above age group (95%CI: 1.41, 38.09). Children whose mothers or caregivers had no education had 3.71 times more odds of being incompletely vaccinated than those whose mothers had secondary school or above education (, 95%CI: 1.21, 11.41). Children from mothers who had no ANC follow-ups had 9.41 times more odds of being incompletely vaccinated than to their counterparts (95%CI: 1.58, 55.93) ().
Table 2. Bi-variate and multivariable logistic regression analysis that shows the association between independent factors with incomplete vaccination among children aged 12–23 months in Kutaber district, northeast Ethiopia, 2017
Discussion
This study assessed the prevalence of incomplete vaccination and associated factors among children aged 12–23 months. The prevalence of incomplete vaccination was found to be 7.7%, and factors associated with incomplete vaccination were educational status, age of the caregiver, place of delivery, history of ANC follow-up and TT vaccination status of the mother. The result of incomplete vaccination in our study is in line with that of a study conducted in Debre-Markos(8.3%).Citation23 However, it is lower than those of studies done in Bangladesh 17%,Citation24 Togo 27.7%Citation17 and Nepal 26%.Citation21 This might be explained by the differences in the study populations because, for example, in Nepal the study on residents of slum areas and economically poorer groups that might have increased the prevalence of incomplete vaccination by decreasing their health-seeking behavior as shown by various studies.Citation5,Citation17,Citation25 The prevalence was also much lower compared to the 2011 EDHS national figure of which was 61%Citation26 The possible reason for the high variation from the EDHS report might be the nationwide nature of the official data because the overall prevalence may be affected by specific areas with extremely high prevalence of incomplete vaccination.
In our study, the odds of having incomplete vaccination was 9.41 times higher among children of mothers with no ANC follow-ups. This result was consistent with those studies conducted in Bangladesh,Citation24 CameroonCitation15 and Gojjam, Ethiopia.Citation20 The result was also in line with a finding conducted in Nigeria which showed that children whose mothers frequented ANC visits to be less likely to have incomplete vaccination.Citation5 This result may be attributed to the fact that mothers who did not attend ANC service had no adequate communication with health care professionals and might not have any information about the routine vaccination processes and the benefits of completing them. Therefore, such mothers might be less motivated to take their child for vaccination service.
In our attempt children whose caregivers were 19–26 years of age had 9.59 times increased odds of having incomplete vaccination. A similar association was found by studies in Bangladesh,Citation16 CameronCitation15 and case-control worked in south Ethiopia.Citation12 This may be explained by the fact that younger caregivers may not have adequate experience in giving care to their children. In addition, older caregivers might face challenges in caring for sick children which exhausts household income. Therefore, such mothers may be highly engaged in such preventive services like vaccination.Citation5
The study showed that children of uneducated mothers had 3.71 times increased odds of having incomplete vaccination status compared to caregivers with secondary and above education. The result was in line with the findings of studies conducted in Togo,Citation19 MozambiqueCitation18 and Bangladesh.Citation16 The possible reason for this association may be to the effect of educational status on seeking health because caregivers with better education have better health-seeking behavior than caregivers with no education.Citation27 In addition, educated mothers could have better knowledge and decision making skills on different issues of child health, including the timing of vaccinating their children compared to uneducated mothers.Citation28,Citation29
This study showed that children born at home had 3.21 times more odds of having incomplete vaccination status than those who were born in health facilities. A similar association was noted by studies conducted in East African countries,Citation30 NepalCitation21 and Gojjam, Ethiopia.Citation31 The result was also consistent with that of a study conducted in Nigeria and showed that children who were born in health institutions to be less likely to have incomplete vaccination than children born at home.Citation5 The possible explanation might be that as mothers deliver at health facilities, they could have the chance for their children to be vaccinated at birth for polio zero and BCG and could be informed about vaccines and when and where to turn for the next vaccination, while mothers who deliver at home miss this opportunity. This is similar to what earlier study reported.Citation5
Our study has shown that nearby (accessible) health facilities were significantly associated with children’s vaccination status, i.e. children living near health posts were 5.65 times more likely to be defaulters compared to children living near to health centers. The possible reason for this association may be that services provided by health extension workers at health post may not satisfy caregivers and as such increase the number of defaulters.
According to our study, children born to mothers with no TT vaccination had 5.26 times increased odds of incomplete vaccination compared to their counterparts. This could be due to mothers’ lack of contact with health professionals resulting in their low awareness about the benefits of complete vaccination. This study has both clinical and public health importance. In its public health aspect, it provides information about factors that contribute to incomplete vaccination which can be worked on to minimize deaths from vaccine-preventable diseases. This will increase the economy of the country by decreasing treatment costs associated with such diseases. Furthermore, knowing the causes of incomplete vaccination can help clinicians to take measures on such factors to decrease the rate of defaulters.
Though the study did its best to identify factors associated with incomplete vaccination in the study setting, it is not free from some limitations. Having used a cross-sectional design, this study has not shown cause and effect relationships among variables. Furthermore, data on health service related issues were not included. Besides, it is presumed that social desirability bias is the other limitation of the attempt.
Conclusion
The rate of incomplete vaccination identified was low compared to the national report. Factors like age educational status the mother/caregiver, TT vaccination of mother, ANC follow-ups, place of delivery and living near health facilities were significantly associated with incomplete vaccination. So, we suggest that the district health office strengthen strategies step up maternal health service utilization. Research to better understand the barrier of maternal health service utilization may also need to be encouraged.
Authors’ contribution
All authors equally contribute for conception and design, acquisition of data, or analysis and interpretation of data. YA, FAM and AML, HFW critically revise the manuscript. All authors read and approved the final version of the manuscript.
Availability of data and materials
The data upon which the result based could be accessed a reasonable request
Disclosure of potential conflicts of interest
No potential conflicts of interest were disclosed.
Ethical approval and consent to participate
This work has been approved by the ethical review committee of the University of Gondar, College of Medicine and Health Science. Written informed consent was also obtained from participants. Participants were clearly informed that they have full right to refuse or withdraw from the study. Privacy of the participants was maintained and individual identifiers were omitted.
Abbreviations
| ANC | = | Antenatal Care |
| AOR | = | Adjusted Odds Ratio |
| BCG | = | Bacille Calmette Guerin |
| CI | = | Confidence Interval |
| EDHS | = | Ethiopian Demographic Health Survey |
| PCV | = | Pneumococcal Conjugate Vaccine |
| PNC | = | Postnatal Care |
| VPN | = | Vaccine Preventable Diseases |
| SD | = | Standard Deviation |
| SSA | = | Sub-Saharan Africa |
| TT | = | Tetanus Toxoid |
Acknowledgments
We would like to express our deepest thanks to the University of Gondar College of Medicine and Health Sciences and Health Officer Department, for facilitating the research work. We also want to thank all pregnant mothers who participated in this study for their contribution.
References
- Duclos P, Okwo-Bele J-M, Gacic-Dobo M, Cherian T. Global immunization: status, progress, challenges and future. BMC Int Health Hum Rights. 2009;9(1):S2. doi:10.1186/1472-698X-9-S1-S2.
- WHO. Immunization coverage WHO; 2016 [Updated September; cited 2017 accessed on Feb.1]. Fact sheet.
- Central Statistical Agency (CSA) [Ethiopia] and ICF. Ethiopia demographic and health survey: key indicators report. In: ICF CSACEa, editor. Addis Ababa, Ethiopia, and Rockville, Maryland, USA: CSA and ICF; 2016.
- Girmay A, Dadi AF. Full immunization coverage and associated factors among children aged 12–23 months in a hard-to-reach areas of Ethiopia. Int J Pediatr. 2019;2019:1924941.
- Adedokun ST, Uthman OA, Adekanmbi VT, Wiysonge CS. Incomplete childhood immunization in Nigeria: a multilevel analysis of individual and contextual factors. BMC Public Health. 2017;17:236. doi:10.1186/s12889-017-4137-7.
- Animaw W, Taye W, Merdekios B, Tilahun M, Ayele G. Expanded program of immunization coverage and associated factors among children age 12 – 23 months in Arba Minch town and Zuria District, Southern Ethiopia. BMC Public Health. 2014;14:464. doi:10.1186/1471-2458-14-464.
- Duclos P, Okwo-Bele JM, Gacic-Dobo M, Cherian T. Global immunization: status, progress, challenges and future. BMC Int Health Hum Rights. 2009;9(suppl 1):S2. doi:10.1186/1472-698X-9-S1-S2.
- Control CfD, Prevention. Global routine vaccination coverage–2012. Morbidity Mortality Weekly Rep. 2013;62(43):858.
- Luman ET, Worku A, Berhane Y, Martin R, Cairns L. Comparison of two survey methodologies to assess vaccination coverage, Oxford University Press. Int J Epidemiol. 2007;36:633–41. doi:10.1093/ije/dym025.
- Vohra R, Vohra A, Bhardwaj P, Srivastava J, Gupta P. Reasons for failure of immunization: A cross-sectional study among 12–23-month-old children of Lucknow, India. Adv Biomed Res. 2013;2(2):71. doi:10.4103/2277-9175.115809.
- Tarantola D, Hacen M, Lwanga S, Clements C. Is immunization coverage in Africa slipping? An evaluation of regional progress to 2013. Ann Vaccines Immun. 2014;1:1007.
- Negussie A, Kassahun W, Assegid S, Hagan AK. Factors associated with incomplete childhood immunization in Arbegona district, southern Ethiopia: a case–control study. BMC Public Health. 2015;16(1):27. doi:10.1186/s12889-015-2678-1.
- Ethiopia C. Ethiopia demographic and health survey. Ethiopia: Central Statistical Agency (CSA) and ICF International; 2011.
- Gurmu E, Etana D. Factors influencing children’s full immunization in Ethiopia. Afr Popul Stud. 2016;6:1.
- Russo G, Miglietta A, Pezzotti P, Biguioh RM, Mayaka GB, Sobze MS, Stefanelli P, Vullo V, Rezza G. Vaccine coverage and determinants of incomplete vaccination in children aged 12–23 months in Dschang, West Region, Cameroon: a cross-sectional survey during a polio outbreak. BMC Public Health. 2015;15:630. doi:10.1186/s12889-015-2000-2.
- Sheikh N, Sultana M, Ali N, Akram R, Mahumud R, Asaduzzaman M, Sarker A. Coverage, timelines, and determinants of incomplete immunization in Bangladesh. Trop Med Infectious Dis. 2018;3(3):72. doi:10.3390/tropicalmed3030072.
- Ekouevi DK, Gbeasor-Komlanvi FA, Yaya I, Zida-Compaore WI, Boko A, Sewu E, Lacle A, Ndibu N, Toke Y, Landoh DE. Incomplete immunization among children aged 12–23 months in Togo: a multilevel analysis of individual and contextual factors. BMC Public Health. 2018;18(1):952. doi:10.1186/s12889-018-5881-z.
- Jani JV, De Schacht C, Jani IV, Bjune G. Risk factors for incomplete vaccination and missed opportunity for immunization in rural Mozambique. BMC Public Health. 2008;8:161. doi:10.1186/1471-2458-8-161.
- Zida-Compaore WIC, Ekouevi DK, Gbeasor-Komlanvi FA, Sewu EK, Blatome T, Gbadoe AD, Agbèrè DA, Atakouma Y. Immunization coverage and factors associated with incomplete vaccination in children aged 12 to 59 months in health structures in Lomé. BMC Res Notes. 2019;12(1):84. doi:10.1186/s13104-019-4115-5.
- Yenit MK AS, Abrha H. Factors associated with incomplete childhood vaccination among children 12–23 months of age in Machakel Woreda, East Gojjam Zone: a case control study. J Preg Child Health. 2015;2:180.
- Shrestha S, Shrestha M, Wagle RR, Bhandari G. Predictors of incompletion of immunization among children residing in the slums of Kathmandu valley, Nepal: a case-control study. BMC Public Health. 2016;16:970. doi:10.1186/s12889-016-3651-3.
- Ebrahim TY, Salgedo WB. Childhood immunization coverage in Tehulederie district, Northeast of Ethiopia: A community based cross sectional study. Int J Curr Res. 2015;7:20234–40.
- Gualu T, Dilie A. Vaccination coverage and associated factors among children aged 12–23 months in Debre Markos Town, Amhara Regional State, Ethiopia. Adv Public Health. 2017;2017. doi:10.1155/2017/5352847.
- Boulton ML, Carlson BF, Power LE, Wagner AL. Socioeconomic factors associated with full childhood vaccination in Bangladesh, 2014. Int J Infect Dis. 2018;69:35–40. doi:10.1016/j.ijid.2018.01.035.
- Amin R, Shah NM, Becker S. Socioeconomic factors differentiating maternal and child health-seeking behavior in rural Bangladesh: a cross-sectional analysis. Int J Equity Health. 2010;9(1):9. doi:10.1186/1475-9276-9-9.
- EDHS Ethiopia. Demographic and health survey 2016: key indicators report. The DHS Program ICF. Ethiopia: Central Statistical Agency (CSA) and ICF International; 2016.
- Chandwani H, Pandor J. Healthcare-Seeking behaviors of mothers regarding their children in a tribal community of Gujarat, India. Electr Physician. 2015;7:990.
- Getachew A, Koye DN, Demssie AF, Zeleke EG, Gelaw YA. Determinants of default to fully completion of immunization among children aged 12 to 23 months in south Ethiopia: unmatched case-control study. Pan Afr Med J. 2016;23:100.
- Jira C. Reasons for defaulting from expanded program on immunization, in Jimma town, South Western Ethiopia. Ethiopian J Health Sci. 1999;9:2.
- Canavan ME, Sipsma HL, Kassie GM, Bradley EH. Correlates of complete childhood vaccination in East African countries. PLoS One. 2014;9(4):e95709. doi:10.1371/journal.pone.0095709.
- Yenit M, Assegid S, Abrha H. Factors associated with incomplete childhood vaccination among children 12–23 months of age in Machakel Woreda, East Gojjam Zone: aCase-controlStudy. J Pregnancy Child Health. 2015;2:180.