Concordance of vaccination status and associated factors with incomplete vaccination: a household survey in the health district of Segou, Mali, 2019
Sidiki Sangaré1, Oumar Sangho2,3,&, Lancina Doumbia3, Hannah Marker4, Yeya dit Sadio Sarro3, Housseini Dolo3, Nouhoum Telly3, Issa Ben Zakour5, Hadji Mamadou Ndiaye6, Moussa Sanogo7, Fanta Sangho2,3, Niélé Hawa Diarra3, Aboubacar Sangho8, Fatoumata Bintou Traoré9, Baba Diallo10, Cheick Abou Coulibaly3, Sadou Ongoiba5, Lamine Diakité11, Seydou Doumbia3
1Health District of Macina, Macina, Mali, 2Department
of Education and Research of Biological and Medical Sciences, Faculty of Pharmacy,
University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali, 3Department
of Education and Research in Public Health and Specialties, Faculty of Medicine
and Dentistry, University of Sciences, Techniques and Technologies of Bamako, Bamako,
Mali, 4Department of International Health, Johns Hopkins Bloomberg
School of Public Health, Baltimore, Maryland, USA, 5Health District
of Segou, Segou, Mali, 6Regional Directorate of Health and Public
Hygiene, Segou, Mali, 7Regional Directorate of Health and Public
Hygiene, Kidal, Mali, 8Department of Education and Research of Pharmaceutical
Sciences, Faculty of Pharmacy, University of Sciences, Techniques and Technologies
of Bamako, Bamako, Mali, 9National Institute of Public Health, Bamako, Mali, 10University
Hospital Center for Odontostomatology (CHU-CNOS), Bamako, Mali, 11Community
Health Center of Pélengana South, Segou, Mali
Oumar Sangho, Department of Education and Research of Biological and Medical Sciences, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
the region of Segou recorded 36.8% of children were incompletely vaccinated
in 2018. In 2019, the district of Segou was one of the districts with the
lowest vaccination coverage in the region, with 85.1% coverage for the three
doses of the
pentavalent vaccine and 85.4% for the measles vaccine. This study was initiated
understand this low vaccination coverage, in the absence of specific studies
on vaccination coverage in the district of Segou.
a prospective cross-sectional study was conducted from May to August 2020 with 30 clusters. We performed Kappa coefficient, bivariate, and multiple logistic regression analysis.
findings showed that 18.46% (101/547) [15.44-21.93] of children were incompletely vaccinated. Mothers correctly reported the vaccination status of their children in 67.30% of cases (Kappa coefficient). Uneducated (OR[IC95%]=2.13[1.30-3.50]), living in rural area (OR[IC95%]=2.07[1.23-3.47]), lack of knowledge of Expanded Program on Immunization (EPI) target diseases (OR[IC95%]=2.37[1.52-3.68]), lack of knowledge of vaccination schedule (OR[IC95%]=3.33[1.90-5.81]) and lack of knowledge of the importance of vaccination (OR[IC95%]=3.6[2.35-6.32]) were associated with incomplete vaccination. In multivariate analysis, uneducated (ORa[IC95%>]=1.68[1.004-2.810]) and lack of knowledge of the importance of vaccination were associated with incomplete vaccination (ORa[IC95%]=3.40[2.049-5.649]).
findings showed a good concordance of the vaccination status. Living in a rural
area, no education, lack of the knowledge of EPI target diseases, lack of the
knowledge of vaccination schedule and lack of knowledge of the importance of
were associated with incomplete vaccination.
The Expanded Program on Immunization (EPI) is a public health intervention
that aims to immunize children around the world to prevent and
to reduce disability and death due to vaccine-preventable diseases
Immunization saves the lives of 2.5 to 3 million children each
In 2018, around 20 million children worldwide did not receive lifesaving
vaccines such as those against measles, diphtheria, and tetanus
and most of those children live in low-income countries and countries
. Factors associated with these inequalities are
identified such us maternal literacy, household residence, sex
of the child, or socio economic status of the parents .
In Mali, despite the more than 30 years of implementing the EPI and the creation
of hundreds of community health centers whose primary objective is prevention
(mainly through vaccination), 41% of children aged 12-23 were incompletely
vaccinated in 2018 . The same year, in the region of
Segou, 36.8% of children aged 12-23 months were incompletely vaccinated .
In 2019, the health district of Segou was one of the districts in the Segou
region with the lowest vaccine coverage, with 85.1% coverage for the three
doses of the pentavalent vaccine, and 85.4% for the measles vaccine .
These vaccination coverage rates are low compared to the target of 95% of the
2017-2021 EPI plan . Unlike other health districts that
had low vaccine coverage, the health district of Segou was not exposed to insecurity
due to intercommunity and religious conflict, which could explain these low
vaccine coverage levels. To better understand these low vaccination coverage
rates, in the absence of specific studies on vaccination coverage in the health
district of Segou, we initiated this study. The objective was to assess the
vaccination coverage, concordance, and the associated factors in children aged
12-23 months in the Malian health district of Segou in 2019.
the study took place in the health district of Segou, located in the center of
the Segou region. In 2019, its population was 608,707 inhabitants.
The vaccination target was estimated at 4% of the population, i.e. 24,348,
of which 40.40%
are reached by the advanced strategy (travel of the vaccinator to
vaccinate children who live more than 5 km from the health center). The district
one referral health center (CSRéf) and 36 health areas (five urban
and 31 rural). Each health area, in addition to the CSRéf, holds at
least one vaccination session in a fixed location each week. Rural
health areas organize advanced vaccination strategy sessions according to
of villages to be vaccinated.
Type and period of study :
this was a prospective cross-sectional community-based study that took place over a period of four months, from May 1st to August 31st, 2020.
included in this study were the mothers of children aged 12 to 23 months living in the Segou health district for at least one year. Mothers of children aged 12 to 23 months who were absent at the time of the survey, and those who declared their children were vaccinated but could not show the vaccination card or the children´s name were not verifiable in the vaccination register, were not included in this study.
the sample size was calculated using the Epi info software version 18.104.22.168 using
the population survey formula (Fleiss). The following parameters were taken into
account in calculating the sample size: confidence level (95%), number of clusters
(30), frequency of children incompletely vaccinated in the region (36.8%), and
cluster effect (1.5). The minimum sample size was estimated to 540 participants
to be surveyed, which we rounded up to 600 people, which represented 20 people
we conducted a cluster survey. In the district, 30 clusters were selected using
the cumulative population size method among 405 villages and neighborhoods. In
each cluster, households were randomly selected by spinning a pen in the middle
of the cluster. Then we followed the direction of the tip of the pen and entered
the first household in that direction to investigate. Once in the household,
all mothers of eligible children were surveyed and we moved on to the next household.
Thus the evolution was made step by step until completing the size of the cluster.
data were collected using a questionnaire tested beforehand. The questionnaire was designed through the adaptation of previous studies [1,8]. Questions were asked on vaccination status of the child, socio-demographic characteristics (i.e. age, marital status, residence, education, number of children, activities generating income) and knowledge about vaccination (i.e. vaccination schedule; EPI target diseases and the importance of vaccination). The vaccination status of the child was then checked on the card or in the vaccination register. From these questionnaires, data were entered into a database on SPSS software.
data were analyzed using the Statistical Package for Social Sciences (SPSS 25.0)
and EPI Info version 22.214.171.124. Vaccination status was the dependent variable.
Age was categorized in three groups: less than 25, 25-33, and 34 and more.
We per-formed a descriptive analysis, and bivariate and multivariate logistic
regression. Kappa coefficient was used to calculate concordance between vaccination
status according to mother declaration and the vaccination status checked on
vaccination card or register. Sensitivity and specificity were evaluated. Sensitivity
was defined as the probability to find an incompletely vaccinated child when
the mother said the child was not completely vaccinated. Specificity was defined
as the probability to find a completely vaccinated child when the mother said
the child was completely vaccinated. Bivariate analysis were conducted and odds
ratios (OR) were presented with a p value of 0.05 as significant level. Variables
that had a significant association during the bivariate analysis were selected
for the multivariate (global) model. Multiple logistic regression was performed
and adjusted odds ratios (ORa) were reported with a p value of 0.05 as significant
level (backward elimination; step by step).
Definition of concepts
fully or completely vaccinated: a child who received one dose of Bacillus
Calmette-Guérin (BCG) vaccine, three doses of oral polio vaccine (OPV)
(excluding OPV given at birth), three doses of pentavalent vaccine, three doses
of Pneumococcal conjugate vaccine (PCV13), one dose of measles vaccine (VAR),
one dose of yellow fever vaccine (AAV) and one dose of meningococcal A vaccine
(MenAfriVac) before 12 months of age.
Incompletely vaccinated: a child who started the vaccination schedule and did not complete it before 12 months of age.
Knowledge of the target diseases of the vaccination: being able to name at least two diseases of the EPI.
Knowledge of the vaccination schedule: being able to cite the five appointments
of the vaccination schedule.
Mother's education: educated (if the mother got school, at least the primary level) uneducated (if the mother had no education, never got school).
Vaccination in advanced strategy: vaccination of children who live more than 5 km away from the health center. Health worker go to such village for vaccination.
Number of appointments: there are five appointments as follow: first:
child who received BCG vaccine before 12 months of age. second: child
who received the first doses of pentavalent vaccine, OPV, PCV13 before 12 months
third: child who received the second doses of pentavalent vaccine, OPV,
PCV13 before 12 months of age.
fourth: child who received the third doses of pentavalent vaccine, OPV,
PCV13 before 12 months of age.
fifth: child who received one dose of BCG vaccine, three doses of OPV,
three doses of pentavalent vaccine, three doses of PCV13, one dose of measles
vaccine (VAR), one dose of yellow fever vaccine (Anti Amaril Vaccine (AAV)) and
one dose of meningococcal A vaccine (MenAfriVac) before the age of 12 months.
this study has been approved by the administrative authorities, the chief of
the health district of Segou and all the community health center authorities
of the Segou health district. The informed consent of the mothers was obtained
verbally after explanations of the study objectives and procedures. This study
had no risk for participants. Participants could withdraw at any time without
consequences. During this survey, confidentiality was guaranteed by not reported
any data linked to the participants.
Of the 600 children, 53 had never been vaccinated and were excluded
from the analysis. The remaining 547 (91.17%) was analyzed. The frequency
of incompletely vaccinated children was 18.46% (101/547) [15.44-21.93].
The frequency of completely vaccinated children was 81.54% (446/547) [78.07-84.56].
Factors associated to vaccination status:
among the 547 participants, 60.15% were aged 25 to 34 years old. Among the participants,
63.07% were uneducated and 67.46% pf them lived in rural area. Uneducated (OR[IC95%]=2.13[1.30-3.50]),
living in rural area (OR[IC95%]=2.07[1.23-3.47]), lack the knowledge of EPI target
diseases (OR[IC95%]=2.37[1.52-3.68]), lack of knowledge of vaccination schedule
(OR[IC95%]=3.33[1.90-5.81]) and lack of the importance of vaccination (OR[IC95%]=3.86[2.35-6.32])
were associated with incomplete vaccination. Our results showed that 35.47% of
the surveyed mother gave birth at home. Approximatively, 51.19% of the children
enrolled in the survey were female (Table
Concordance of immunization status:
the sensitivity of the declaration of mothers on the vaccination status of children (Se) was 56.43% and the specificity of the declaration of mothers on the vaccination status of children (Sp) was 99.77%. The Kappa reproducibility coefficient was 67.30% (Table 2).
Factors associated with incomplete immunization:
Using multivariate analysis, uneducated and lack of the importance of vaccination were associated with incomplete vaccination given Adjusted Odds Ratios of ORa[IC95%]=1.68[1.004-2.810] and ORa[IC95%]=3.40[2.049-5.649] respectively (Table 3).
results showed that more than 80% of children were completely vaccinated. This
vaccination coverage completeness was high compared to the 52% of
the Mali sixth Demographic and Health Survey (DHS), but low compared
to the target
of 95% of the 2017-2021 EPI plan [5,7].
The vaccination coverage found corroborates those of previous studies
with 77.9% in Kouroussa, Guinea , 72.2% in Senegal
and 76.8% in Ethiopia . Our vaccination coverage
was greater than those found in Cameroon 64.3%  and
in Ethiopia with 38.3% [12,13].
This difference could be explained by the differences between the
data collection sources, based on the vaccination card and the vaccination
register in our
study versus the vaccination card and the verbal statement of mothers
for the studies in Cameroon and in Ethiopia, with possibility of
loss of information. Our vaccine completeness was lower than that
of a study in Kaolack,
. This gap could be explained at the level of the
health system. In the Segou health district, the vaccination was
done using different strategies like fixed strategy (done at the
health centers), advanced
strategy (done in the village far from the health centers).
These strategies are not the same used in Kaolack, where vaccination takes place
daily, using only the fixed strategy. This daily availability of vaccination
services and its integration in the general health services could give many
children the chance to complete their vaccinations. By comparing the information
provided by the mothers on the vaccination status of the children with the
information on the vaccination cards or in the vaccination register, we found
a Kappa coefficient of reproducibility of 67.30%. This concordance shows that
in more than 67% of the cases, the statements made by the mothers were correct.
This match could be used as an argument for carrying out large-scale studies
on the vaccination status of children only based on mother's reports. Our agreement
was better than that of Adedire et al. in 2016 who found a rate of 33.6%
in Nigeria .
Factors associated with incomplete vaccination.
Residence and education:
living in rural area and being uneducated were associated with incomplete vaccination.
Indeed, children whose mothers did not attend school and who live in rural areas
had approximatively 3 times more risk of being incompletely vaccinated compared
to children whose mothers were educated and live in urban areas. Previous studies
conducted in Africa also found that literacy and education are factors associated
with the vaccination status of children: OR[CI95%]=2.34[1.12, 4.47] in Nigeria
in Ivory Coast , OR[CI95%]=0.56[0.33-0.95] in Malawi
, OR[CI95%]=1.38[1.07 1.78] in Ethiopia ,
OR[CI95%]=2.2 [1.6; 3.1] in Togo [20,21],
OR[CI95%]=18.4 [4.01-84.62] in Somalia .
The education leads to the intellectual development of women and the possibility
of access to many channels of information on routine vaccination while enhancing
their attendance of vaccination services.
Knowledge of Vaccination:
lack of awareness of the importance of vaccination was associated with incomplete
vaccination of children. Children whose mothers did not understand the importance
of vaccination were more than 3 times more likely to be incompletely vaccinated
than those whose mothers did understand the importance of vaccination. Other
authors have also highlighted the association between knowledge of the importance
of vaccination and vaccination status in Cameroon (OR[CI95%]=4,4[1,35-14,42])
, in Ethiopia (OR[CI95%]=1.9 [1.44-2.49]), (OR[CI95%]=2.24[1.68-2.98])
[8,12], in Nigeria (OR[CI95%]=2.4 [1.6-3.8])
, in Kenya (OR[CI95%]=2.21[1.22-3.98]= .
Knowledge of routine vaccination information by the community improves their
adherence to the EPI.
Limitations of the study :
rotateq and IPV were not included in the definition of full vaccination for this
study due to an untimely shortage of Rotateq and the similarity between IPV and
OPV. The dates of vaccine administration were not taken into account but rather
vaccine completeness before 12 months. These limitations do not affect the validity
of the study. However, they can be considered selection biases as the inclusion
of Rotateq and IPV in the definition would reduce the number of participants
is the study.
Our findings showed a good concordance of the vaccination status as reported
by the mother and the official vaccination document. Living in a rural area,
education, lack of the knowledge of EPI target diseases, lack of knowledge
of vaccination schedule and lack of knowledge of the importance of vaccination
were significantly associated with incomplete vaccination. The good agreement
as reported by Kappa coefficient in this study could be used as justification
for conducting large-scale study on vaccination status based on mothers' reports
as proxy measure.
What is known about this topic
- Low vaccination completeness in Africa;
- Factors associated with this vaccination incompleteness are multiple vary from one country to another.
What this study adds
- Findings of this study show that not knowing the vaccination schedule, and
the importance of the EPI are strongly associated to the incompleteness of
the vaccination in the district of Segou;
- There is consistency between the vaccination status reported by the mothers and the information in the vaccination documents.
The authors declare no competing interests.
Sidiki Sangaré and Oumar Sangho analyzed and interpreted data and wrote the
manuscript. Lancina Doumbia and Hannah Marker translated and corrected the
manuscript. Yeya dit Sadio Sarro, Housseini Dolo, Nouhoum Telly, Issa Ben
Zakour, Hadji Mamadou Ndiaye, Moussa Sanogo, Fanta Sangho, Niélé Hawa Diarra,
Aboubacar Sangho, Fatoumata Bintou Traoré, Baba Diallo, Cheick Abou Coulibaly,
Sadou Ongoiba, Lamine Diakité and Seydou Doumbia reviewed the manuscript.
All authors read and approved the final manuscript.
The study authors gratefully acknowledge all the health care providers
in the Community Health Centers, the Community Health Workers,
the surveyors and the villages surveyed.
Table 1: sociodemographic, economic characteristics and mothers' knowledge of vaccination in the health district of Segou in 2019
Table 2: distribution of the vaccination status of children declared by mothers and that verified in the vaccination materials
Table 3: factors associated with incomplete vaccination in children aged 12-23 months in the health district of Segou in 2019 (multivariate analysis)
- Ba Pouth SFB, Kazambu D, Delissaint D, Kobela M. Couverture vaccinale et facteurs associés à la non complétude vaccinale des enfants de 12 à 23 mois du district de santé de Djoungolo-Cameroun en 2012. Pan Afr Med J. 2014;17:97. Google Scholar
- Organisation Mondiale de la Santé. La santé et le bien-être: objectif 3 de dévelop-pement durable. 2019.
- Organisation Mondiale de la Santé. Vaccination.
- Organisation Mondiale de la Santé. State of inequality:
childhood immunization. 2016.
- Institut National de la Statistique (INSTAT), Cellule de Planification et de Statis-tique Secteur Santé-Développement, ICF. Enquête Démographique et de Santé au Mali 2018. 2019.
- Direction Régionale de la Santé et de l´Hygiène Publique de Ségou. Annuaire Statis-tique Sanitaire 2019 du Système Local d´Information Sanitaire de la Région de Ségou. 2020.
- Direction Nationale de la Santé. Plan Pluri-annuel Complet (PPaC) 2017-2021 du Programme Elargi de la Vaccination du Mali. 2017.
- Ababu Y, Braka F, Teka A, Getachew K, Tadesse T, Michael
Y et al. Behavioral determinants of immunization service utilization
in Ethiopia: a cross-sectional community-based survey. Pan Afr Med J. 2017;27(Suppl
2):2. PubMed | Google
- Ngwa W, Mupenda J, Haba B, Nanan-N´Zeth K, Bachy
C, Pineda S. Enquête de couverture vaccinale multi antigénique
Préfecture de Kouroussa. 2019.
- Mbengue MAS, Mboup A, Ly ID, Faye A, Camara FBN, Thiam M et al. Vaccination coverage and immunization timeliness among children aged 12-23 months in Senegal: a Kaplan-Meier and Cox regression analysis approach. Pan Afr Med J. 2017;27(Suppl 3):8. PubMed | Google Scholar
- Legesse E, Dechasa W. An assessment of child immunization coverage and its determinants in Sinana District, Southeast Ethiopia. BMC Pediatr. 2015;15:31. PubMed | Google Scholar
- Lakew Y, Bekele A, Biadgilign S. Factors influencing full immunization coverage among 12-23 months of age children in Ethiopia: evidence from the national de-mographic and health survey in 2011. BMC Public Health. 2015;15:728. PubMed | Google Scholar
- Tamirat KS, Sisay MM. Full immunization coverage and its associated factors among children aged 12-23 months in Ethiopia: further analysis from the 2016 Ethiopia demographic and health survey. BMC Public Health. 2019;19(1):1019. PubMed | Google Scholar
- Seck I, Diop B, Leyé MM, Mbacké Mboup
B, Ndiaye A, Seck PA et al. Déterminants sociaux de la couverture
vaccinale de routine des enfants de 12 à 23 mois dans la région
de Kaolack, Sénégal. Sante Publique. 2016;28(6):807-815. PubMed | Google
- Adedire EB, Ajayi I, Fawole OI, Ajumobi O, Kasasa S,
Wasswa P et al. Immunisation coverage and its determinants among children
aged 12-23 months in Atakumosa-west district, Osun State Nigeria: a cross-sectional
study. BMC Public Health. 2016;16(1):905. PubMed | Google
- Oleribe O, Kumar V, Awosika-Olumo A, Taylor-Robinson SD. Individual and socio-economic factors associated with childhood immunization coverage in Nigeria. Pan Afr Med J. 2017;26:220. PubMed | Google Scholar
- Fatiregun AA, Okoro AO. Maternal determinants of complete child immunization among children aged 12-23 months in a southern district of Nigeria. Vaccine. 2012;30(4):730-736. PubMed | Google Scholar
- Sackou KJ, Oga ASS, Desquith AA, Houénou Y, Kouadio
KL. Couverture vaccinale complète des enfants de 12 à 59 mois
et raisons de non-vaccination en milieu péri-urbain abidjanais en 2010.
Bull Soc Pathol Exot. 2012;105(4):284-290. PubMed | Google
- Ntenda PAM, Chuang KY, Tiruneh FN, Chuang YC. Analysis
of the effects of individual and community level factors on childhood immunization
in Malawi. Vaccine. 2017;35(15):1907-1917. PubMed | Google
- Zida-Compaore WIC, Ekouevi DK, Gbeasor-Komlanvi FA,
Sewu EK, Blatome T, Gbadoe AD et al. Immunization coverage and factors
associated with incomplete vaccination in children aged 12 to 59 months in
health structures in Lomé. BMC Research Notes. 2019;12. PubMed | Google
- Landoh DE, Ouro-kavalah F, Yaya I, Kahn A-L, Wasswa P, Lacle A et al. Predictors of incomplete immunization coverage among one to five years old children in Togo. BMC Public Health. 2016;16(1):968. PubMed | Google Scholar
- Jama AA. Determinants of complete immunization coverage among children aged 11-24 months in Somalia. Int J Pediatr. 2020;2020:5827074. PubMed | Google Scholar
- Maina LC, Karanja S, Kombich J. Immunization coverage and its determinants among children aged 12-23 months in a peri-urban area of Kenya. Pan Afr Med J. 2013;14:3. PubMed | Google Scholar