[version 1; peer review: 2 approved with reservations]
No competing interests were disclosed.
Tetanus is a non-communicable and dangerous disease caused by a toxin released from
Maternal and neonatal tetanus prevention relies on unsafe delivery avoidance, abortion and umbilical cord care practices, and the promotion of tetanus immunization
By the end of 2017, tetanus immunization had a global coverage of 86%
The aim of this study was to assess tetanus vaccine coverage in the Foumban Health District (FHD) among mothers in terms of the number of recommended protective doses for the latest pregnancy and for the cumulative number of vaccine doses administered.
This study was implemented following national and international regulations in research participant’s protection. All heads of household were informed and their permission obtained before meeting eligible participants. All participants were informed about the study via the information sheet and their written consent for participation and publication of the collected data was obtained before collecting their data. The information contained in their antenatal care (ANC) booklet was kept confidential and only data needed for the study were collected. We obtained ethical clearance from the National Ethical Committee for Human Health Research (N° 2019/05/20/CE/CNERSH/SP of May 6, 2019) and an administrative authorization letter from the FHD Medical Officer (N° 247/L/MINSANTE/SG/DRO/DS/FBAN of November 22, 2018).
This was a descriptive community-based cross-sectional survey conducted among former parturient women of the FHD in 2019. A cluster randomized sampling design was used to select participants from whom trained surveyors collected the data using a face-to-face method.
The study was conducted from July 2018 to July 2019. Recruitment and data collection were conducted from May 2019 to June 2019, following receipt of ethical approval for the study.
The FHD is located in the west region of Cameroon, bordered by four other health districts of the same region and by the North West Region in the North. It has a surface area of 1,734 km². The FHD is made up of 22 health areas with a total population of 235,828 inhabitants in 2018
The target population was women of childbearing age with at least one child aged 0–59 months living in FHD for at least three months. Those absent from selected households for two visits in a week were not included.
The sample size was estimated at 620, using a confidence interval of 95% and precision of 5% and assuming the immunization coverage in the Cameroon general population to be 73.9% from a previous demographic health survey (DHS 2011)
The estimated sample size was assigned to 10 health areas (HA) selected from the 22 HA of the FHD by a stratified random sampling process. At the HA level, 62 quarters were selected using a systematic sampling method. The number of clusters per HA was proportional to the total population of the HA and 10 mothers were included per quarter. The listing of all localities was done in alphabetical order with the cumulative population frequency. The sample interval in each HA was determined by dividing the total population of the area by the allocated number of clusters. In each village/quarter, one direction or street was randomly selected from the centre. We included the first household on the right and another one after, skipping two households. We further chose the participant in the selected households. If there were two or more mothers in a household, we randomly chose one, and if there were no eligible woman, the next household was included in the study.
The data collection tools were developed by the study team and pre-tested among 14 women in the community for fluency, acceptance by participants and precision. Following pre-testing, the questionnaire was divided into a questionnaire, a data extraction grid and a data tracking grid and some questions were adapted or removed to make questions more pertinent and reduce the time taken to administer the questionnaire (from ~30 minutes to ~10 minutes). The questionnaire (see
Trained surveyors conducted a face-to-face interview at the participant’s home to collect data from eligible mothers. Surveyors were male and female community health workers with at least three years of experience. Before beginning, the aim of the study was explained in the information sheet and written informed consent was obtained. Interviews were 5–10 minutes in duration. Data collected included: age; education level; marital status; profession; parity; knowledge of tetanus vaccine; availability of ANC booklet and immunization card; and doses of tetanus toxoid vaccine received since their first pregnancy, during their last pregnancy and during their last three pregnancies, with earlier pregnancies not considered to reduce the possibility of memory bias. The information sources were recall and evidence of vaccination (Td cards and ANC booklets).
There was a high probability of recall bias as data were collected using a questionnaire. We cannot be certain of the respondent statements, as some may not have a good memory of vaccination from many years ago or some could for some reason hide or deform some answers. The research team could not overcome this weakness as it cannot be avoided when data are collected using questionnaires. Nevertheless, some key variables were collected from vaccination cards filled out by health personnel and we believe these have less risk of being affected by information bias.
We assessed the survey coverage and response rate per cluster to mitigate the risk of selection bias. Data were analyzed by estimating the proportion of mothers with each dose of tetanus vaccine received, the proportion of documented immunization coverage, undocumented immunization coverage and stratification by education level. Attempting to infer results to the general population, proportions were estimated with 95% confidence intervals. Data were entered and analyzed using Epi Info version 7.2.2.6
Out of 621 participants reached, 602 responded, giving a response rate of 96.9% (CI 95%: 95.6-98.3). The mean age of participants was 28.4±8 years. The coverage rate of the 62 clusters was 100% and the response rate varied from 94.3% to 100%. Out of 602 participants, 483 were Muslim (80.2%, CI 95%: 77.1-83.4) and 319 were housewives (52.9%, CI 95%: 49.0-56.9). Secondary education was the most represented education level among participants.
| Socio-demographic
|
Frequency (n) | Proportion (%) | CI 95% | |
|---|---|---|---|---|
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| ≤19 | 50 | 8.4 | 6.4 | 10.8 |
| 20–24 | 164 | 27.4 | 23.9 | 31.1 |
| 25–35 | 270 | 45.1 | 41.1 | 49.1 |
| >35 | 115 | 19.2 | 16.2 | 22.6 |
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| Illiterate | 30 | 4.9 | 3.2 | 6.7 |
| Primary | 239 | 39.7 | 35.8 | 43.6 |
| Secondary | 321 | 53.3 | 49.3 | 57.3 |
| Higher | 6 | 1.0 | 0.2 | 1.8 |
|
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| Civil servant | 35 | 5.8 | 3.9 | 7.7 |
| Farmer | 32 | 5.3 | 3.5 | 7.1 |
| Trader | 112 | 18.6 | 15.5 | 21.7 |
| Housewife | 319 | 52.9 | 49.0 | 56.9 |
| Other | 92 | 15.3 | 12.4 | 18.2 |
|
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| Single | 69 | 11.5 | 8.9 | 14.0 |
| Married | 477 | 79.2 | 76.0 | 82.5 |
| Divorced | 33 | 5.5 | 3.7 | 7.3 |
| Widow | 20 | 3.3 | 1.9 | 4.8 |
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| <=19 | 410 | 71.4 | 67.6 | 74.9 |
| 20–24 | 137 | 23.9 | 20.6 | 27.5 |
| 25–35 | 27 | 4.7 | 3.3 | 6.8 |
| >t35 | 0 | 0.0 | 0.0 | 0.0 |
In our study, 176/511 (34.4%, CI 95%: 30.3-38.6) women had ANC booklets or immunization cards (Td card). 111/511 (21.7%, CI 95%: 18.1-25.3) participants had documented immunization coverage of two or more tetanus doses (Td2+) and 243/511 (47.6%, CI 95%: 43.2-51.9) had undocumented immunization coverage. The high proportion of unprotected births 102/280 (36.4%, CI 95%: 30.8-42.1) was among those education to secondary education level.
| Tetanus dose received
|
Education level [ n (%) ] | Total
|
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|---|---|---|---|---|---|
| Illiterate (n=23) | Primary
|
Secondary
|
Higher
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| Less than two vaccination doses | 0 (0.0) | 17 (8.4) | 48 (17.1) | 0 (0.0) | 65 (12.7) |
| At least two vaccination doses | 2 (8.7) | 46 (22.7) | 62 (22.1) | 1 (20.0) | 111 (21.7) |
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2 (8.7) | 63 (31.0) | 110 (39..3) | 1(20.0) | 176 (34.4) |
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| Less than two vaccination doses | 5 (21.7) | 32 (15.8) | 54 (19.3) | 1 (20.0) | 92 (18.0) |
| At least two vaccination doses | 16 (69.6) | 108 (53.2) | 116 (41.4) | 3 (60.0) | 243 (47.6) |
|
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21 (91.3) | 140 (68.9) | 170 (60.7) | 4 (80.0) | 335 (65.6) |
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| Less than two vaccination doses | 5 (21.7) | 49 (24.1) | 102 (36.4) | 1 (20.0) | 157 (30.7) |
| At least two vaccination doses | 18 (78.3) | 154 (75.9) | 178 (63.6) | 4 (80.0) | 354 (69.3) |
Td card, tetanus vaccine immunization card; ANC, antenatal care.
The recruitment, two and five doses completeness rates were 569/570 (99.9%, CI 95%: 99.5-100), 546/570 (95.8%, CI 95%: 94.2-97.5) and 372/570 (65.3%, CI 95%: 61.4-69.2), respectively. Among former parturient women, 306/570 (53.7%, CI 95%: 49.6-57.8) had received more than five tetanus vaccine doses (
| Estimated cumulative
|
Education level [n (%)] | Total (n=570) | |||
|---|---|---|---|---|---|
| Illiterate (n=25) | Primary (n=230) | Secondary (n=309) | Higher (n=6) | ||
| 0 | 0 (0.0) | 0 (0.0) | 1 (0.32) | 0 (0.0) | 1 (0.2) |
| At least 1 | 25 (100.0) | 230 (99.9) | 308 (99.7) | 6 (100.0) | 569 (99.9) |
| At least 2 | 25 (100.0) | 226 (98.3) | 289 (93.5) | 6 (100.0) | 546 (95.8) |
| At least 5 | 21 (84.0) | 169 (73.5) | 179 (54.9) | 3 (50.0) | 372 (65.3) |
| More than 5 | 17 (68.0) | 149 (64.8) | 140 (45.3) | 0 (0.0) | 306 (53.7) |
| Estimated
|
Number of pregnancies [ n (%) ] | Total (n=576) | |||
|---|---|---|---|---|---|
| 1
|
2
|
3
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More than
|
||
| 0 | 0 (0.0) | 0 (0.0) | 1 (0.9) | 0 (0.0) | 1 (0.2) |
| 5 | 89 (100.0) | 95 (91.4) | 42 (40.0) | 39 (14.0) | 265 (46.0) |
| 10 | 0 (0.0) | 9 (8.7) | 62 (59.1) | 141 (50.7) | 212 (36.8) |
| 11 – 15 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 71 (25.5) | 71 (12.3) |
| >15 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 27 (9.7) | 27 (4.7) |
The documented vaccination coverage of at least two doses of tetanus vaccine at the end of the previous pregnancy was 21.7% and increases to 69.3% when the mother's statements about their vaccination status (undocumented vaccination coverage) are taken into account. Taking into account the total number of tetanus vaccine doses received during all pregnancies by each woman, the first contact, two and five doses completeness rate was 99.9%, 95.8% and 65.3%, respectively. Over half (53.3%) of participants had received more than five tetanus vaccine doses.
To protect the child from tetanus, it is recommended that a minimum of two doses of this vaccine be administered to each woman before the end of pregnancy
The two-dose immunization coverage from immunization cards and declarations indicates that three out of 10 babies are born unprotected against tetanus. The fact that a significant proportion of newborns are unprotected against tetanus is concerning for our national elimination status. This could be explained by limits in the supply of vaccination
The tetanus immunization schedule during pregnancy in Cameroon is based on the WHO recommendations
Our results showed that 65.3% of mothers had completed five doses of the tetanus vaccine and that 53.7% had received more than the five maximum recommended doses for lifetime protection
The estimated coverage of vaccination during the last pregnancy and cumulative number of doses from all pregnancies was expected to be based on data collected from the Td card or ANC booklet; however, only a third of the participants had evidence of vaccination. We had to collect this data using a tracking tool to assess the vaccination status of women that had no evidence of vaccination. Using two data sources to estimate this coverage can lead to information bias that may question the validity of our results. This is a difficulty encountered in almost all of the vaccination coverage surveys that we tried to solve by using a vaccine status-tracking grid. The limitations of the current study have lead our team to launch two other studies: a study to document and respond to reasons for the unavailability of evidence of vaccination and a study to test tools that allow with certain reliability to determine the vaccination status of women who have no evidence of vaccination.
The present study indicates that more than half of the participants received more doses of vaccines than recommended for adequate protection against tetanus of the mother and the child during the mother's childbearing years. This increases the need for resources and the cost of vaccination. This study also showed that the vaccine coverage and the level of protection of this vaccine in pregnant women are underestimated if estimates do not take into account the cumulative number of doses of vaccine received by the mother before and during previous pregnancies. To improve the situation, we recommend training health personnel to assess the vaccination status before planning the number of doses of vaccines to be administered to a pregnant woman. Moreover, the same document should be used for all antenatal consultations across pregnancies to allow a better assessment of the number of vaccine doses already administered. Scientists should identify and respond to the reasons for the unavailability of evidence of vaccination and test vaccine status tracking tools in women who have no source of verification of vaccine status.
Figshare: Tetanus vaccine coverage in recommended and more than recommended doses among mothers in a West Cameroon Health District: MetaData.
Figshare: Questionnaire.
Figshare: Data extraction grid.
Figshare: Data tracking grid.
Data are available under the terms of the
We are grateful to the Health District Service of Foumban, the Faculty of Medicine and Pharmaceutical Sciences of the University of Dschang and the National Ethical Committee for Human Health Research for giving us formal authorization to carry out this study. We thank the non-governmental organization M.A. SANTE (Foumban Office) for technical and logistical support. We thank all the participants, and the Health Areas Chief of Foumban Health District for facilitating data collection. We also thank all those who contributed to the realization of this work.
Foumban Health District is not a standard term, it needs more clarification. Year of survey needs to be mentioned in the abstract. The definition of outcome variable also needs to be mentioned in the abstract. The first 2 paragraphs in the introduction are very general in description and should be replaced by something more substantial: contextual factors, what progress has been made so far, what challenges lie ahead, what should be done etc. The following study was not cited: Chiabi
What the present study is contributing to the literature should also be mentioned.
Is the work clearly and accurately presented and does it cite the current literature?
Yes
If applicable, is the statistical analysis and its interpretation appropriate?
Partly
Are all the source data underlying the results available to ensure full reproducibility?
Yes
Is the study design appropriate and is the work technically sound?
Partly
Are the conclusions drawn adequately supported by the results?
Yes
Are sufficient details of methods and analysis provided to allow replication by others?
No
Reviewer Expertise:
Maternal and child health
I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.
Thank you Sir Ghose Bishwajt for your critical reading and comments on this article; We will consider them when correcting.
Best,
This is a descriptive cross sectional study from Cameroon to assess receipt of the appropriate doses of tetanus vaccines by mothers for protective immunity against tetanus. The authors interviewed women of child bearing age with at least one child and reviewed ANC and immunisation records and if unavailable relied on maternal recall to determine tetanus vaccination history.
The key finding in this study was that over 50% of women had received greater than 5 doses of tetanus vaccine, the required number for long-term protection against tetanus. The authors also identified 36.4% of births to be unprotected from tetanus.
This is an important study which highlights vaccine wastage as women received more than the required doses of tetanus vaccine. The authors were limited by unavailability of documentation on maternal vaccination status with reliance on maternal recall. There is however a disconnect between the background provided, the aim of the study and the results described. Specific comments are provided below.
The background would benefit from including the justification for the study (why was this study undertaken?). The authors stated: "the number of doses recommended by the Expanded Program of Immunization...". Doses of which vaccine? Please specify the vaccine being studied.
"infection occurs after abortion, miscarriage...". This implies that tetanus always occurs following these events. Authors should clarify, providing references, that the main cause of tetanus infection is from unhygienic delivery practices which may occur during childbirths or miscarriage/abortion (spontaneous or induced) and may also result in neonatal tetanus. Suggest that authors include standard definition for PAB with a reference. Have the authors reviewed the literature for similar studies where more than the recommended tetanus doses are administered to pregnant women and the reasons for this? If there are no other studies, clarify this in the methods.
How were heads of household contacted and informed about the study?
Suggest that authors clarify that method was "face-to-face" interviews. Was a woman with a live birth an inclusion criteria, or were women with stillbirths and miscarriages included.
The authors should clarify whether it is standard practice for women to have home based ANC records or whether ANC cards are usually kept at health care facilities. Authors should also clarify whether tetanus immunization is recorded in ANC records or an independent immunization card or both.
Suggest the authors clarify whether maternal recall is equivalent to undocumented immunization.
The authors should clarify the importance of stratifying by education level. There is no mention of the source of funding.
It is recommended to not begin sentences with numeric e.g. 111/115 etc.
The authors mention "unprotected at birth". Was PAB measured and if so how? This would need to be clarified in the methods. Maternal TT/Td coverage is not equivalent to PAB.
Expanding on the details of Table 4 would be useful as the results need to be standing alone from the tables.
Is the work clearly and accurately presented and does it cite the current literature?
Partly
If applicable, is the statistical analysis and its interpretation appropriate?
Yes
Are all the source data underlying the results available to ensure full reproducibility?
Yes
Is the study design appropriate and is the work technically sound?
Yes
Are the conclusions drawn adequately supported by the results?
Yes
Are sufficient details of methods and analysis provided to allow replication by others?
Partly
Reviewer Expertise:
Vaccinology, epidemiology, public health
I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.
Thank you Sir Jayani Pathirana for the time you have taken to review the paper. Your suggestion will be taken into account.
In response to your concerns, the study was conducted to access the Td vaccine community coverage because despite the good national coverage published, this region was victim of many epidemics situation of certain diseases under surveillance.
During the implementation, data were collected:
- using a face-to-face method from women of childbearing age with at least one child, after obtaining the verbal authorization of their husband (according to the cultural reason of the study area) and the written consent of the women concerned.
- from the antenatal care booklets or vaccination cards (depending of their availability at the health facilities) because, in our context, theses evidences of immunization are given to the women who are responsible for keeping them.
- from maternal recall in case of absence of the previous document (undocumented immunization).
Cordially,