Measles, a highly contagious airborne disease, caused approximately 2.6 million deaths annually before measles vaccination was introduced in 1963 [1] . It remains responsible for hundreds of thousands of deaths and severe illnesses among children worldwide [2] . Although the number of cases drastically decreased thanks to vaccination, a global resurgence of cases has been observed since 2019, linked to the COVID-19 pandemic which weakened health systems and fostered vaccine-related misinformation [3] [4] .

To protect populations against the spread of measles, the World Health Organization (WHO) recommends at least 95% vaccination coverage. However, this target remains out of reach in many African countries. Between January 2020 and April 2021, nearly 17 million African children missed measles vaccine doses. Vaccination coverage had been hovering between 70% and 75% for a decade, risking dangerous gaps in immunity [6] . In the long run, this could lead to an increase in potentially fatal cases and push measles eradication further away, leaving millions of children vulnerable to this disease [4] . Measles incidence is often used as an indicator of a health system’s capacity to deliver essential pediatric vaccines [5] . In Benin, 28 measles outbreaks were reported in 2018, and 14 municipalities reached their epidemic threshold [7] . According to the fifth Demographic and Health Survey (DHS-V), measles vaccination coverage in Benin was 68% in 2018 [8] , indicating a high level of vulnerability among children. Childhood vaccination is influenced by parental decision-making. Parents base vaccination decisions on their knowledge of vaccines and related factors [9] .

The objective of this study was to assess mothers’ knowledge of measles with the ultimate aim of contributing to reductions in infant and child mortality.

This was a descriptive cross-sectional study with analytical objectives over a 5-month period (1 April to 31 August 2024). The study population consisted of mothers of children under 5 years of age in the municipality of Parakou, selected by systematic random cluster sampling. The inclusion criteria were: (1) residence in Parakou for at least six months, and (2) having at least one living child under five years of age. The minimum sample size was calculated using Schwartz’s formula: n = zα²pq/i² with α = 5% (type I error rate), hence zα = 1.96; p = 53.6%: proportion of people with good knowledge of measles and its vaccine in a study in Lubumbashi [10] ; q = 46.4%; i = 5%: margin of error or desired precision. Calculated n = 382 mothers of children. This size was increased by 10%, so the final size was n = 420 mothers of children.

The calculated sample size was 420 mothers. Knowledge level was assessed using an ad hoc composite scoring grid developed by the research team. The dependent variable was the level of knowledge about measles, assessed using nine sub-variables scores developed by the research team based on the members’ experience in managing measles: knowledge that measles is a childhood disease; knowledge of at least two symptoms (e.g., cough, coryza, conjunctivitis, maculopapular rash); understanding that measles is communicable; knowledge of transmission via coughing, sneezing, or saliva; awareness of the existence of a measles vaccine; knowledge of the recommended vaccine age (9 months); understanding that there is no age limit for contracting measles; knowledge that measles can be fatal; and knowledge of the role of vitamin A in the body. Each sub-variable was scored from 0 to 1. Overall scores were calculated and expressed as percentages: ≥70% = good; 40% - 69% = moderate/acceptable; <40% = poor. Independent variables included sociodemographic, socioeconomic, sociocultural, and organizational factors. Data were collected using a structured questionnaire on the KoboCollect application by a team of final-year bachelor students from the National School for the Training of Higher Technicians in Public Health and Epidemiological Surveillance (ENATSE), over a two-week period (5-20 May 2024). For quantitative variables, measures of central tendency (mean ± standard deviation) were used. For qualitative variables, proportions with 95% confidence intervals (CIs) were reported. For analytical purposes, the three categories of the dependent variable were dichotomized into: good knowledge (good + acceptable levels) and poor knowledge (poor level). Prevalence ratios (PRs) with 95% CIs were used to assess associations. A p-value < 0.05 was considered statistically significant.

Ethical and deontological considerations: The protocol was submitted to the ENATSE validation committee for approval. Authorization was obtained from the Coordinating Physician of the health district. Verbal informed consent was obtained from all participating mothers, and anonymity and confidentiality of collected data were maintained.

Of the 420 mothers targeted, 390 were surveyed, representing a participation rate of 92.85%.

Based on nine sub-variables, 225 mothers (57.69%; 95% CI: 52.74% - 62.50%) had a good level of knowledge of measles ( Figure 1 ).

For the sub-variables: 88.97% recognized measles as a childhood disease, 82.05% identified at least two symptoms, and 75.13% were aware of the vaccine.

Table 1 shows the distribution of mothers according to their knowledge of measles.

Given the prospective nature of the study and the due diligence performed, no mother meeting the inclusion criteria and included was excluded, reducing the risk of selection bias. However, as with any interview-based study, especially in our cultural context where there is a risk of pleasing the interviewers by giving convenient answers, information biases are potential.

The bivariate analysis used in this study is susceptible to confounding bias, which could be addressed in future analyses using multivariate logistic regression. Therefore, the associated factors identified should be interpreted with caution.

In this study, fewer than six in ten mothers of under-five children had a good level of knowledge about measles. Age, profession, monthly income, possession of information on epidemic-prone diseases, history of eruptive diseases in offspring, and access to social networks were associated with knowledge level. The low maternal knowledge observed may contribute to recent measles outbreaks. These associated factors should be further investigated using more in-depth multivariate analyses.