VoICE Immunization Evidence: Sociocultural Inequity
Key Evidence: In households with seven or more members, the odds of a child receiving full immunization coverage were roughly 20% lower than in households with only three members, even after accounting for the effect of wealth quintile, religion, and population density.
Key Evidence: Children who were born as the fourth or fifth child in their household were more than twice as likely to be incompletely vaccinated with BCG, measles vaccine, and pentavalent vaccine than those who were born as the second or third child in their household.
Key Evidence: Children of Bangladeshi mothers younger than 34 years were more than three times as likely to have incomplete vaccination compared to children of mothers older than 35 years.
Key Evidence: In a systematic review of qualitative research from low- and middle-income countries, women’s low social status was shown to be a barrier to their children accessing vaccinations. Specific barriers included access to education, income, resource allocation, and autonomous decision-making related to time. The authors suggest that expanding the responsibility for children’s health to both parents (mothers and fathers) may be one important element in removing persistent barriers to immunization often faced by mothers.
Children from poorer refugee and migrant families have less access to health services and lower vaccination rates than the surrounding population.
Key Evidence: A study found that children of poor labor migrants living in Delhi, India are much less likely to be fully vaccinated than the general population and thus are at greater risk of vaccine-preventable diseases. Only 31% – 53% of children from migrant families were fully immunized (against 7 diseases) by 12 months of age, compared to 72% in the overall population of Delhi — with recent migrants having the lowest rates. There is therefore a need to focus on the delivery of health services to migrants.
Key Evidence: Somali refugee children in Kenya were nearly 60 times more likely than children of the main ethnic group in the study (Kikuyu) to not have received any childhood immunization and more than twice as likely to have not completed their vaccinations. Although Somali children made up less than 8% of the sample, they accounted for nearly half of all non-vaccinated children.
From the VoICE Editors: This study used data from Kenya’s Demographic and Health Survey data.
Key Evidence: Recent migrants face barriers to accessing health care including language and cultural barriers, limited knowledge, food and housing insecurity, stress, and lack of resources available during prolonged travel. In Canada, though foreign-born populations make up only 22% of the total population, 70% of active tuberculosis cases occurred in this population.
Key Evidence: Girls from refugee families in Denmark were 40-56% less likely to receive HPV vaccine through 2 free-of-charge immunization programs than Danish-born girls, and the differences remained significant when income was taken into account. The odds of being vaccinated were lowest for refugees in the country ≤5 years and those from certain countries or regions, indicating the need to reduce cultural, social, and information barriers to immunization, as well as assess immunization programs across increasingly ethnically diverse societies.
Key Evidence: In a study of timely measles vaccination – – defined as vaccination within one month of the recommended age – – children living in Zheijiang province in China whose families immigrated from elsewhere in the country were 2.6 times more likely to receive the first measles dose late and nearly 3 times more likely to receive the second dose late than were children originally from the area.
Key Evidence: Children in Shanghai, China whose families migrated from rural areas — now roughly 40% of the city’s total population — are half as likely as “local” children to receive the first dose of measles vaccine by 9 months of age and 42% less likely to receive the second measles dose by 24 months. The lower rates of timely first dose measles vaccination among rural migrants vs. local children — 78% vs. 89% – – are a key obstacle to measles elimination in China. This indicates a need to specifically target non-local children for vaccination, especially those living in primarily migrant communities.
Key Evidence: A study in Canada linking hospital data with census and immigration databases found that immigrants had age-adjusted hospitalization rates from vaccine-preventable diseases that were 33% higher than the rates of the Canadian-born population (1.6 vs. 1.2 per 10,000,) and rates were highest among refugees (1.7/10,000) and immigrants from East and Southeast Asia (2.1/10,000). Sixty percent of the hospitalizations related to vaccine-preventable diseases among recent immigrants were due to chronic hepatitis B infection, suggesting the need for hepatitis B screening guidelines for migrants, as well as vaccinations against a range of diseases for immigrants prior to or upon their arrival.
Inequities exist in marginalized populations and minority groups who may have poorer access to health services including immunizations.
Key Evidence: Children born to North Korean refugee women in China have much lower vaccination rates than local Chinese or migrant children — with full immunization rates of 14% compared to 93% for local ethnic Chinese children and 55% for migrant children. While all ethnic Chinese children are registered and provided with free vaccinations and there are specific programs targeting migrant children, children born to Korean refugees have no legal status and are thus excluded from the public health care system.
Key Evidence: In contrast to non-Somalis, family wealth did not significantly affect the likelihood of being fully vaccinated among Somali refugee children living in Kenya. This may point to systemic barriers to vaccination that cut across all socio-economic levels of the Somali refugee population.
Key Evidence: Native populations experience barriers to health care access such as limited knowledge, stigma, community social isolation, and geographic isolation. As a result, Inuit populations in Canada suffer 300 times higher rates of TB than the Canadian-born non-Indigenous population.
Key Evidence: An analysis of survey data in Latin America and Caribbean countries found that DPT3 coverage rates among indigenous children were significantly lower than in children of European or mixed ethnicity in three out of 14 countries, while significant inequities between these groups in coverage of maternal health services, such as antenatal care and delivery by a skilled birth attendant, existed in most of the countries. The greater equity in access to childhood vaccination by ethnic group may be because vaccinations are often delivered in the communities through immunization campaigns, whereas maternal health services require accessing health facilities, which may incur user fees and transportation costs.
Key Evidence: Children of Maori and Pacific Island ethnicities in New Zealand had lower rates of age-appropriate vaccination than other ethnic groups, according to a large retrospective study.
Key Evidence: In a study of invasive pneumococcal disease in neonates in New Zealand following the introduction of pneumococcal conjugate vaccine (PCV) for infants, 67% of the cases in children <7 days old were of Maori ethnicity, while Maoris make up only 27% of New Zealand’s population. This over-representation of Maoris may be due to poverty and crowded living conditions and suggests that crowded households may be slower to experience the benefits of population-wide pneumococcal vaccination.
Key Evidence: In New Zealand, Maori and Pacific children have historically suffered high hospitalization rates for invasive pneumococcal disease (IPD), all cause pneumonia (ACP), and otitis media. Following the introduction of conjugate vaccines in the country, Maori and Pacific children’s rates of admission for IPD dropped by 79% and 67%, respectively, while significant reductions in ACP and otitis media admissions were also noted, resulting in reductions in disparities for these populations.
Key Evidence: Coverage rates of HPV vaccination in England, which is provided to 12-13 year old girls through a government-funded, school-based program, were significantly lower in areas with higher proportions of migrant families and non-whites than in areas that are predominantly native-born and white.
Key Evidence: Children of unemployed mothers in Bangladesh were 1.5 times as likely to have incomplete vaccination status compared to children of employed mothers. Maternal unemployment was also significantly linked to delays in BCG and measles vaccinations.
Key Evidence: The 2008 Nigerian Demographic Health Survey data suggest that children in communities with high unemployment were 1/3 as likely to be fully immunized than children in communities with a medium level of unemployment.
Key Evidence: Children of divorced mothers were three times less likely to be fully immunized than mothers cohabitating with a partner. In addition, it was found that children of mothers who work part time were approximately 2.3 times less likely to be fully immunized than mothers who work full time.
From the VoICE Editors: This study, conducted in Ghana, used Chi-Squared analysis to determine adjusted odds ratios. Multivariable analysis was not conducted.