Unlocking the Puzzle: How Immunization Shapes Child Growth and Stunts Stunting

Edward Jenner developed the world’s first vaccine in 1796—a vaccine for smallpox, a deadly disease that killed millions yearly. Jenner’s vaccine came from the observation that milkmaids infected with cowpox, a milder disease, were immune to smallpox. He hypothesized that if he could infect someone with cowpox, they would then be immune to smallpox. Jenner tested his hypothesis by inoculating 8-year-old James Phipps in a medical breakthrough. It was the first vaccine to be developed against a contagious disease, and it helped eradicate smallpox in the world in 1980.

While smallpox was eradicated in 1980, several diseases and conditions that need to be eradicated for improved child outcomes continue.

Do we need to solve the ‘stunting problem’?

During the same time, researchers were still debating upon the interpretation of stunting, for example:

“I think it’s dangerous to talk about the ‘problem of stunting.’ Is ‘stunting’ a problem, or is ‘poverty’ a problem for which stunting could be an indicator? If we go on using the term ‘stunting problem,’ we might be formulating ‘stunting control programs,’ which could create the illusion that we can solve the ‘stunting problem.’ But why should we solve a so-called ‘stunting problem’ as such and let the problem of poverty remain? Such ‘stunting control programs’ would divert attention from looking at the real solutions, which conceptually are much more difficult to develop and will certainly go far beyond what is considered to be the territory of the nutritionist.”

Use and Misuse of Stunting as a Measure of Child Health

Stunting, a stubborn health issue, affects 148 million children, associated to varying degrees with several risk factors. Incomplete immunisation is a significant risk factor for stunting. Poverty, inadequate access to healthcare, and poor sanitation contribute to incomplete immunisation and stunting. Vaccinating children can strengthen their immune systems and protect them from illnesses like hepatitis B, diphtheria, pertussis, tetanus, pulmonary TB, measles, and rubella. Several research studies have been conducted to understand and explore the relationship between stunting and immunisation.

Can we immunise children against stunting?

Achieving high immunisation coverage rates is essential for promoting child growth and development. Immunisation protects children from infectious diseases and secondary infections, possibly responsible for malnutrition and hinder growth.

Immunisation can also indirectly enhance child nutrition by promoting maternal health and increasing household food security. Vaccination programs often provide nutrition education, maternal and child health services, and other essential services that can improve maternal and child health outcomes, including child growth.

However, it is crucial to note that the relationship between immunisation status and stunting occurrence is likely bidirectional. Stunted children may have weaker immune systems and be more susceptible to infectious diseases, affecting their immunisation status. Therefore, a comprehensive approach is necessary to address the complex and multifaceted causes of malnutrition and stunting.

Incomplete immunisation, incomplete protection

Children who receive incomplete immunisation have a 1.2 times greater risk of stunting than those who receive complete immunisation. The incidence of stunting in children under five in various nations was examined by Afework, Mengesha, and Wachamo (2021). Four of the articles concluded that there was a substantial association between stunting and insufficient primary immunisation.

For instance, a study conducted in India showed that insufficient primary immunisation correlates with the incidence of stunting in children under the age of five. These findings are consistent with a study from the West Guji Zone, Oromia, Ethiopia, which found that only 45 (24.5%) of the stunted group’s children had received an entire primary immunisation course, compared to 199 (34.1%) who had not.

These results from research done in Ethiopia’s Gimbi and Machakel Woreda areas show children who were not immunised were at risk of contracting infectious diseases like measles, pneumonia, and diarrhoea, which could lead to malnutrition and stunting.

Biology of non-immunised children

According to a systematic analysis, children under five must receive all the recommended immunisations to preserve immunity until adulthood, as full immunisation for children under five can strengthen their immune systems.

Children without/incomplete immunisations have weaker immune systems than immunised children and are more likely to contract infections and fall sick. They are likely to experience infectious diseases that can make them lose their appetite, making it harder for the body to absorb nutrients to minimise weight. Long-term illness increases the likelihood of stunted growth.

Therefore, parents must ensure their kids receive the full complement of basic immunisations to lower the risk of illness and prevent the child from contributing to stunting.

Additional factors hindering immunisation

However, several additional factors can still contribute to stunting in children aged 6–59 months, even after receiving all the recommended vaccinations. Low birth weight, supplementary foods for breast milk, the mother’s education, early marriage, birth spacing, and other factors contributed to stunting.

For example, studies conducted in Ghana and Mexico found that children born to younger women were more vulnerable to the double burden of malnutrition. Younger women often have poor nutritional status, leading to poor fetal growth and development. Additionally, younger mothers may lack the knowledge and resources to adequately care for their children adequately, exacerbating the problem.

Guye et al. (2023) found that various factors, such as lapses in vaccination schedules, parental migration, excessive work demands, the spread of rumours and misinformation, concerns about vaccine side effects, occasional unopened vaccine vials for certain children, the closure of health posts when mothers visit, and the absence of health extension workers at these posts, serve as significant obstacles to achieving complete vaccination coverage for children.

Future research

As one of the most cost-effective healthcare measures, the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) stress vaccination as a fundamental component of universal health coverage, essential for achieving optimal health worldwide. Seizing every opportunity to ensure that children and adults receive vaccinations according to the routine immunization schedule is imperative.

Therefore, it is essential to identify effective strategies for promoting immunisation and child development to further our understanding of the mechanisms behind the relationship between stunting and immunisation. Future studies could investigate the correlation between specific vaccine types and child growth outcomes. They might explore potential interactions between vaccines and other interventions, such as nutrition programs.

At the same time, paying attention to the socio-economic precedents of stunting, such as poverty, that press upon the dearth of required resources to raise healthy children is essential. As researchers debated in the 1980s, by only aiming to solve a so-called ‘stunting problem’ via ‘stunting control programs, ’ we might divert attention from looking at the real solutions, which conceptually are much more challenging to develop and will certainly go far beyond what is considered to be the territory of the nutritionist.”