Progress, challenges and priorities in eliminating maternal and neonatal tetanus in the African region from 2016 to 2024: cross-sectional retrospective analysis

¹World Health Organization, Regional Office for Africa, Brazzaville, Republic of Congo, ²World Health Organization, Headquarters, Geneva, Switzerland, ³World Health Organization, Eastern Mediterranean Region, Cairo, Egypt

^&Corresponding author
André Arsène Bita Fouda, World Health Organization, Regional Office for Africa, Brazzaville, Republic of Congo

Introduction    

Tetanus is an acute infectious disease caused by a neurotoxin produced by Clostridium tetani bacteria whose resistant spores are present in soil and in the environment and can easily enter the body through contaminated wounds [1]. Unclean delivery is one of the main causes of maternal and neonatal tetanus (MNT). MNT has been among the most common life-threatening consequences of unclean deliveries and umbilical cord care practices such as cutting the umbilical cord with unsterile instruments and the application of traditional substances in the umbilical stump [2,3]. Maternal and neonatal tetanus remains a major public health problem in African region despite decades of tremendous efforts to control and eliminate the disease [3,4]. MNT is a deadly disease with an 80-100% case-fatality rate among neonates especially in areas with poor immunization coverage and limited access to clean deliveries [3].

In 1989, the World Health Assembly endorsed the global initiative to eliminate neonatal tetanus by 1995 [5]. In 1990, the resolution was modified to include maternal tetanus (MNTE) because tetanus also affects mothers, and a target date of 2020 was set after the initial target dates of 2005 and 2015 were missed while targeting 59 priority countries that were considered at high risk of MNT. Of the 59 priority countries, thirty-two of these high-burden countries are in the AFR. The MNTE initiative aims to reduce MNT cases to such low levels that the disease is no longer a major public health problem [6].

MNTE is defined as having less than one neonatal tetanus case per 1000 livebirths in every district each year, is also used as a proxy for maternal tetanus elimination [7]. MNT deaths can be easily prevented by hygienic delivery and cord care practices, and/or by immunizing children and women with tetanus toxoid-containing vaccines (TTCV), which are inexpensive and very efficacious, through the life course. The strategies for elimination include vaccinating ≥ 80% of pregnant women in all districts with at least 2 doses of TTCV2 +, targeting ≥ 80% of women of reproductive age (WRA) aged 15-49 years in high-risk districts with TTCV through rounds of supplementary immunization activities (SIAs), promoting clean births and umbilical cord care so that ≥ 70% of women having access to skilled birth attendance (SBA), and strengthening NT surveillance including case investigation and response [6-9].

Despite several missed deadlines to achieve MNTE, only ten countries of the originally targeted 59 high-risk countries, including four in the AF,R namely Angola, Central African Republic, Nigeria, and South Sudan are yet to achieve MNTE as of December 2024. Some of these countries achieved elimination between 2016 to 2024 (Figure 1) [10,11]. In addition, partial elimination has been achieved in Nigeria (southeast, southwest, south-south, and north-central geopolitical zones) [11-17]. WHO estimates that in 2023, 4,585 newborns died from NT, a 75% reduction from the situation in 2000 figure of 17,935 [10]. This study aimed to assess the progress, challenges, and perspectives to MNTE in the AFR from 2016 to 2024.

Methods     

A cross-sectional retrospective study was conducted focusing on the twelve countries in AFR that were yet to achieve MNTE as of 2016. These are namely Angola, Chad, Central African Republic, Democratic Republic of Congo (DRC), Equatorial Guinea, Ethiopia, Guinea, Kenya, Mali, Niger, Nigeria, and South Sudan. This list includes four countries (Angola, Central African Republic, Nigeria, and South Sudan) that have not yet achieved elimination as of December 2024. We reviewed the performances of the core MNTE indicators in these countries against the standard performance thresholds. The core indicators include the annual reported neonatal tetanus (NT) cases, proportions of women that received at least two doses of tetanus-toxoid containing vaccines (TTCV2+), women whose newborns were protected at birth (PAB) against tetanus, women whose deliveries were assisted by skilled birth attendants (SBA: doctors, nurses, and midwives), and women who delivered in health facilities. Information from the unpublished reports of MNTE post-validation assessments was used to complement the findings while a scoping review of literature allowed regional and across-country comparisons.

We extracted from the 2023 (the year of the most recent and complete data) WHO/UNICEF electronic Joint Reporting forms (eJRF) [11] of each concerned country, the reported NT cases and, the official reported TTCV2+ coverage. Data for protected at birth (PAB) were extracted from the WHO/UNICEF estimates of national immunization coverage (WUENIC) for 2022 as published on the WHO websites [12]. Additional data on PAB and TTCV2+, and on SBA and health facility deliveries (HFD) were extracted from the most recent household surveys (demographic and health surveys - DHS and multiple cluster indicator surveys - MICS) [13,14]. Data were analyzed using Microsoft Excel and the results of the analysis were presented in tabular and graphic forms.

Results     

Eight (67%) of the 12 high-risk countries in AFR achieved maternal and neonatal tetanus elimination (MNTE) as of December 2024, leaving four countries that are yet to achieve elimination. All except two of the eight countries were validated for elimination between 2016 and 2019, before the COVID-19 pandemic started. In the post-pandemic era, only two countries, Guinea and Mal,i were validated for elimination, though validation of elimination of the south-south and north-central geopolitical zones of Nigeria was conducted in 2022 and 2023, respectively (Table 1). In 2023, a total of 1,395 neonatal tetanus cases were reported in the twelve countries, with cases ranging from 9 in Equatorial Guinea to 410 in the Democratic Republic of Congo.

The annually reported NT cases in the 12 countries increased by 38% from 1012 in 2016 to 1395 in 2023, while the average percentage of protected at birth (PAB) as estimated for countries fell slightly from a peak of 77% in 2017 and 2018 to 74% in 2023 (Figure 2). The administratively reported coverage in the 12 countries for two or more doses of tetanus toxoid-containing vaccines (TTCV2+) as reported through the 2023 eJRF ranged from 30.5% in Equatorial Guinea to 120% in the Central African Republic. Triangulating these administrative coverage results with those from the most recent household surveys, the TTCV2+ coverage ranged from 35.7% in Mali to 60.8% in Nigeria. The percentage of protected at birth (PAB) against tetanus, a more comprehensive documentation of protection, from the household surveys ranged from 49.6% in Mali to 70.2% in Nigeria. Based on household survey data, the percentages of deliveries that were assisted by skilled birth attendants and health facility delivery were highest in Kenya (97.7% and 82.3% respectively) and lowest in Ethiopia (27.3% and 26.2% respectively) (Table 1). In addition, five AFR countries (Burkina Faso, Cameroon, Uganda, Gabon, and Ivory Coast) that achieved elimination before 2016 successfully conducted post-validation assessments during the 2016-2024 timeframe.

Discussion     

From 2016 to 2024, eight countries (Chad, DRC, Equatorial Guinea, Ethiopia, Guinea, Kenya, Mali, and Niger) made tremendous efforts by eliminating MNT nationwide, and in addition, partial validation of MNT elimination was achieved in the southeast, south-west, south-south, and north-central geopolitical zones of Nigeria. However, these efforts fell short of the global goal of achieving MNTE by 2015, including in the AFR [16,17]. On average, two countries were validated annually for elimination between 2016 and 2019; however, that number dropped during the COVID-19 pandemic and the period immediately after, when no country was validated between 2020 and 2022. The pause of MNTE implementation activities during the COVID-19 pandemic, and particularly of the conduct of supplemental TTCV vaccination rounds for women of childbearing age, was a major setback to the initiative in the region. Several studies reported a similar impact on mass vaccination campaigns for other antigens during the pandemic. An article on the impact of the SARS CoV-2 on vaccine-preventable disease campaigns found that in May 2020, 105 of 183 (57%) campaigns were postponed or canceled in 57 countries, with an estimated 796 million postponed or missed vaccine doses [18].

Another systematic review study on the impact of COVID-19 pandemic on immunization campaigns highlighted a breakdown in polio campaigns that coincided with an upsurge in polio cases in Afghanistan and Pakistan [15]. For countries that completed their rounds of supplemental vaccination campaigns against tetanus before the COVID-19 pandemic or immediately after, assessments including validation surveys were least prioritized by countries in the face of other competing priorities such as catching up on routine immunization doses and response to huge outbreaks of vaccine-preventable diseases such as diphtheria, measles, circulating vaccine-derived poliovirus (cVDPV) and cholera. Limitation in access by populations to health services, especially in security-compromised parts of countries, was also a major factor that led to delays in the achievement of MNTE. The validation surveys in Mali and DRC were delayed due to limited access of populations to health services, including tetanus immunization, and the same factor continues to delay the achievement of MNTE in Nigeria, the Central African Republic, and South Sudan [19-21]. Several peer-reviewed papers have documented the negative impact of insecurity-related limitations of access to populations on health program implementation and assessments [22-24]. MNTE core performance indicators in the countries provide insight into the trajectory of the countries towards achieving elimination in the four countries that are yet to meet this goal and for maintenance of elimination in the eight countries that have achieved elimination. The elimination thresholds expected for achieving and sustaining MNTE include Neonatal tetanus rates of less than one case per 1000 livebirths, 80% or above coverage for the protected at birth or two doses or more of tetanus toxoid-containing vaccines and 70% or above coverage for skilled birth attendance at delivery at the district level [25-27]. Our study shows an overall increase in the annually reported NT cases between 2016 and 2023 in the 12 countries despite the majority having achieved elimination, a pattern which could be attributed to possible improvement in the NT surveillance quality allowing for the detection of cases that would have been previously missed. The non-attainment of the PAB or SBA elimination thresholds in Chad (PAB = 73%, SBA = 47.2%) and Guinea (PAB = 75%, SBA = 55.3%) signals the possibility that, despite achieving elimination, these countries are facing challenges maintaining their elimination status. On the other hand, the date of the most recent household surveys in these countries from which the SBA coverage was extracted may precede the year of achievement of elimination. The marked differences between the administratively reported coverage data and those from the household surveys underscore the data quality issues inherent in the former source of data, where TTCV2+ coverage is perpetually under-reported due to limited skills among health workers to comprehensively record all doses received by pregnant women during ANC visits including births attended in private health care settings that are not included leading to under reporting. In most cases, while health workers may not vaccinate pregnant women that have completed 5 doses of TTCV in line with a previous WHO recommended 5-dose policy [28], most of the pregnant women in this category may not be included in the calculation of two doses or more, of the tetanus toxoid-containing vaccine (TTCV2+) in the health facility register.

The most recent WHO recommendation is to provide a total of 6 doses of TTCV throughout the life course [29]. PAB coverage, designed to help overcome the underestimation of the level of protection against tetanus through TTCV vaccination has had very little uptake by AFR countries, while the annual WHO estimates may also lack accuracy and household surveys that are conducted every five years may not provide timely data. Strengthening the technical capacity of health workers to comprehensively compute TTCV2+ and the promotion of routine PAB monitoring and reporting by AFR countries will go a long way to addressing the current TTCV2+ underestimation. Tetanus Seroprotection surveys, considered as the “gold standard” for providing objective biological measure of population immunity, [5] are rarely conducted in the AFR. A serological survey conducted in Nigeria in 2018 showed that overall, 70.9% and 84.3% of children aged <15 years had at least minimal seroprotection against tetanus and diphtheria, respectively. Seroprotection was lowest in the northwest and northeast zones with <80% [30]. A similar study in Burkina Faso in 2002 showed that weighted TT coverage was 74.4% and tetanus antitoxin seroprevalence was 88.7% [31]. Investing in periodic tetanus vaccine sero-survey in the AFR remains critical.

Competing public health priorities such as responses to frequent disease outbreaks, focus on efforts to catch up and restore routine immunization coverage post-COVID-19 pandemic, scarcity of financial resources and lack of prioritization of MNTE by countries continue to result in the low uptake of the SAGE recommendation to conduct periodic post-validation assessments. The countries that achieved elimination between 2016 and 2024 have been affected by these factors and none has conducted this assessment since achieving elimination. Considering that C. tetani, the causative bacterium of tetanus, remains ubiquitously in the environment, assessing possible barriers to sustaining elimination and implementing corrective strategies remains crucial to avoid the resurgence of MNT in the Region [15].

Limitations This retrospective study is limited by the quality of data used, over which the authors had no control. Administratively reported coverage data from countries suffer from unreliable numerators and denominators at national and sub-national levels. Household survey data used for some of the countries in this analysis may not reflect the present situation, given that they were conducted several years in the past. The authors had no control over the quality of the data. National averages reported in the study throughout in our analysis may hide significant subnational level gaps. Moreover, the true assessment of MNTE performance is at the district level.

Conclusion     

Despite not meeting the target goal of MNTE by 2020, the AFR made tremendous progress over the past two decades, with an additional eight countries validated for elimination between 2016 and 2024. Contextual factors continue to delay the achievement of elimination in the remaining four countries in the region. Periodically assessing elimination status and implementing strategies that prevent the resurgence of MNT are currently not prioritized in the region. Attaining and sustaining MNTE in the AFR requires that the existing barriers be addressed.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

Conceptualization, writing - original draft methodology, data curation, validation, software, visualization, formal analysis, writing, reviewing and editing: André Arsène Bita Fouda. Conceptualization, methodology, data curation, validation writing, reviewing and editing: Charles Shey Wiysonge, Nasir Yusuf, Balcha Girma Masresha, Ado Mpia Bwaka, Joseph Nsiari-muzeyi Biey, Crépin Hilaire Dadjo, Shibeshi Messeret Eshetu, Franck Fortune Roland Mboussou, Abdu Abdullahi Adamu, Diana Chang-Blanc, Benido Impouma. Supervision: Benido Impouma. All authors read and approved the final version of the manuscript.

Acknowledgments     

The authors acknowledge the WHO AFRO Member States, UNICEF, CDC.

Table and figures     

Table 1: maternal and neonatal tetanus progress and performances of core indicators in the 12 African Region countries that were yet to achieve elimination as of 2016.

Figure 1: elimination status of MNT from 2000 to June 2024

Figure 2: trend of annually reported neonatal tetanus cases and average yearly % protected at birth coverage in the 12 AFR countries that were yet to achieve MNTE as of 2016

References