Determinants of Measles Vaccine Hesitancy among Sudanese Parents in Khartoum State, Sudan: A Cross-Sectional Study

"As exposure to anti-vaccine information predicts measles vaccine hesitancy among parents, investment in vaccine communication will be a cost-effective intervention for measles vaccine acceptance and demand."

Although the benefits of strong immunisation programmes are clear, suboptimal coverage exists among specific populations in certain low- and middle-income countries (LMICs). Vaccine hesitancy is one of the main predictors of low vaccine acceptance and demand: A 2019 study by the present group of researchers (available at Related Summaries, below) conducted among immunisation experts and vaccine providers in Sudan showed that measles vaccine hesitancy exists in Sudan, a country that has experienced recent measles outbreaks. To further inform the development of relevant policies and interventions, this community-based cross-sectional quantitative study assessed measles vaccine hesitancy and characterised the determinants of hesitancy among Sudanese parents.

The researchers surveyed 500 parents/guardians with a child aged 2-3 years in Omdurman, Khartoum State in February 2019. They used the Parent Attitudes about Childhood Vaccination (PACV) to measure measles vaccine hesitancy and asked questions about the sociodemographic characteristics of the family, parents' perceptions about the measles vaccine, and parental exposure to information. Proportions of vaccine hesitancy and coefficients of linear regression were computed.

The majority of children whose caregivers were surveyed were fully vaccinated with the measles vaccine (87.2%), though a significant proportion (about 1 in 5 parents) had hesitations regarding the measles vaccine. The PACV's items are categorised in three subscales:

• Immunisation behaviour: 17.8% of the respondents have delayed having their child receive a shot for reasons other than illness or allergy.
• Perceived safety and efficacy: 16.6% were (very) concerned that the measles vaccine might not be effective, 13% were (very) concerned that the vaccine might not be safe, and 19% were (very) concerned that their child might have serious side effects from the measles vaccine.
• General attitudes and trust: Only 3.6% of the participants considered themselves to be (very) hesitant about childhood measles shots. The vast majority of the participants (96.2%) reported they trust the information they receive about measles shots, and they have trust in their child's doctors (88%).

More than three-quarters of the participants (77.4%) reported they have been exposed to pro-vaccination information or materials; only 13% of the participants reported they have ever been exposed to anti-vaccination information or materials. Not surprisingly, parents in the latter group are more likely to be hesitant toward the measles vaccine. One of the anti-vaccine information messages circulating in the Sudanese community is that measles is a common household disease that can be contracted by every child, so topical or traditional medication can treat it. "These findings suggest the importance of developing tailored vaccine communication strategies and interventions to increase confidence in vaccines and to reduce measles vaccine hesitancy among at-risk groups who are mostly exposed to negative information about the vaccine."

In addition to parental exposure to anti-vaccination information or materials, other significant predictors of measles vaccine hesitancy were the parents' perception of the effectiveness of measles vaccines, the age of the mother (measles vaccine hesitancy increased with the increase in the age of the mother), the birth rank of the child (measles vaccine hesitancy was negatively associated with the rank of the child), and the total number of the children in the family (measles vaccine hesitancy increased with the number of children).

The latter finding may be attributed to the fact that Sudanese mothers are mostly the ones responsible for the health and prevention of sickness of their children and family; therefore, larger families with many children under five years may increase the burden of mothers and may reduce the quality of care for the siblings. In light of this finding, the researchers suggest that fathers' involvement may help reduce delays in vaccination in situations where the mother is unavailable due, for example, to the need to care for the other family members.

Fifty-nine parents (12%) who partially vaccinated or did not vaccinate their children with the measles vaccine justified their hesitancy for different reasons. Most of the cited reasons were related either directly or indirectly to access issues (i.e., availability of the measles vaccine and vaccinators' attitude), as well as inconvenience, such as practical and social circumstances that prevented timely attending of measles vaccination sessions. One suggestion at the programme level is that the Expanded Program on Immunization set up parental reminders to address the long period between the vaccines generally and, in particular, for the 9th and 18th month measles' doses.

In conclusion, this study finds that measles vaccine hesitancy in Sudan is determined by various interrelated factors that range from individual to societal levels. Overall, the "findings indicate that investment in vaccine communication as well as addressing access issues might be an effective intervention for improving measles vaccine acceptance and, ultimately, measles vaccine coverage."