Enhancing vaccine outcomes through nutrition
World Immunisation Week (24 – 30 April) prompts us to acknowledge the role of vaccines in preventing disease and death. Arguably the most significant medical innovation of the last century, vaccines cost-effectively save millions of lives by preventing life-threatening diseases. The World Health Organisation (WHO) estimates that 4 million deaths are prevented each year, thanks to vaccines. 1
As reported by the WHO, “in addition to offering protection from preventable diseases, immunisation also brings children and families into contact with health systems, providing an avenue for the delivery of other basic health services and laying the foundation for primary health care. As such, ensuring universal access to vaccines is a critical entry point for universal health coverage (UHC)”. 1
Vaccine Preventable Diseases (VPDs) persist in Africa
Children in sub-Saharan Africa are 15 times more likely than those in high-income countries, to die before the age of 5. More than half of these deaths are preventable through interventions such as immunisation and good nutrition. 2
The VPDs that affect African populations include: 1
Outbreaks of these diseases persist in Africa as a result of insufficient immunisation coverage, low access to immunisation services, or interruptions of these services. These outbreaks affect more than 30 million African children under the age of 5 and claim 58% of global VPD deaths.1
A significant factor is the inequalities in vaccination coverage, which persist in sub-Saharan Africa. Continued efforts are required to enhance access to affordable vaccination services for all. “Vaccination programmes should target critical social determinants of health and address barriers to better maternal health-seeking behaviour.” Improved maternal education has been cited as an important intervention and this is where healthcare professionals can play a formidable role.3
Public health interventions should target uneducated or poor families, as well as those that have not used maternal health services. 3 Data capturing, surveillance and monitoring of child immunisation are also recommended, to help prevent disease outbreaks. 4
The link between nutrition and immunisation
Scientists have found a complementary relationship between vaccination and nutrition, noting that good nutrition supports immunity and recovery from illness. 5 In addition, it is hypothesised that vaccine response is delayed in malnourished children, further highlighting the importance of good nutrition as part of an effective vaccine strategy. 6
One study established that “children who failed to receive all twelve vaccinations before age 1, as recommended by the national immunisation programme, showed an association with malnutrition (stunting and overweight in boys and wasting in girls) in early life compared with children who were fully vaccinated by their first birthday”.7
Good nutrition is believed to improve the efficacy of vaccines and researchers are working to understand how different foods (and nutritional supplements) can become part of the vaccine treatment plan.
Probiotics are believed to improve vaccine efficacy
There is growing evidence that probiotics boost immunity. In addition, various studies appear to suggest that probiotic treatment can improve the efficacy of vaccines, and the duration of their protective effects, cost effectively. 8 9
This study hypothesises that intestinal dysbiosis may be a major factor for the inefficacy and adverse effects of COVID-19 vaccines, especially in vulnerable populations. Modulation of the intestinal microbiome with probiotics and bacterial metabolites is proposed by the researchers, as means to improve the health of the gut microbiota, thereby mediating COVID-19 vaccine efficacy. 10
Further research is necessary to understand which probiotic strains and doses have optimal outcomes.
Breastfeeding is shown to improve infant response to vaccines
UNICEF states that “breastfeeding acts as a baby’s first vaccine, providing critical protection from diseases and death”.11
Recent studies have found that breastfeeding offers other additional benefits. The infant vaccination process can be stressful for new mothers and their babies, and breastfeeding is believed to help both mother and baby to cope better with this. Breastfeeding can also “improve response to vaccines in the still maturing immunologic and enterohepatic systems of infants; and influence physiologic parameters that can change the metabolism of ethylmercury derived from some vaccines”. 12
Recent studies have found that women vaccinated against COVID-19 (or infected with the virus) passed antibodies to their infants via their breastmilk, “suggesting a potential protective effect against infection in the infant”. 13
Thus it is recommended that infants be fed breastmilk exclusively for the first six months, and continue breastfeeding up to 2 years of age. 14
Healthcare professionals should promote the benefits of childhood vaccinations and good nutrition
The WHO believes that vaccine hesitancy is one of the 10 threats to global health.15 It recently updated its recommended schedule for childhood vaccinations (the downloadable document is available here) and is prioritising universal health coverage.
“Providing parents and other community members with information on immunisation, health education at facilities in combination with redesigned immunisation reminder cards, regular immunisation outreach with and without household incentives, home visits, and integration of immunisation with other services, may improve childhood immunisation coverage in low- and middle-income countries.”16
Healthcare professionals are ideally positioned to promote the benefits of healthy nutrition as well as vaccinations; to provide accurate information about them and VPDs; as well as support patients in adhering to the government-recommended child vaccination schedules and dietary guidelines. After all, it is “thanks to immunisation efforts worldwide, children are able to walk, play, dance and learn. Vaccinated children do better at school, with economic benefits that ripple across their communities. Today, vaccines are estimated to be one of the most cost-effective means of advancing global welfare”.17
 WHO | Regional Office for Africa. n.d. Immunization. [online] Available at: <https://www.afro.who.int/health-topics/immunization> [Accessed 11 March 2022].
 Tesema, G., Tessema, Z., Tamirat, K. and Teshale, A., 2020. Complete basic childhood vaccination and associated factors among children aged 12–23 months in East Africa: a multilevel analysis of recent demographic and health surveys. BMC Public Health, 20(1).
 Bobo, F., Asante, A., Woldie, M., Dawson, A. and Hayen, A., 2022. Child vaccination in sub-Saharan Africa: Increasing coverage addresses inequalities. Vaccine, [online] 40(1), pp.141-150. Available at: <https://www.sciencedirect.com/science/article/pii/S0264410X21014390> [Accessed 11 March 2022].
 Bateman, C., 2021. Drop in child vaccinations a danger. Mail & Guardian, [online] Available at: <https://mg.co.za/health/2021-05-10-drop-in-child-vaccinations-a-danger/> [Accessed 11 March 2022].
 Scalingupnutrition.org. 2020. The power of connecting vaccines and good nutrition -. [online] Available at: <https://scalingupnutrition.org/news/the-power-of-connecting-vaccines-and-good-nutrition/> [Accessed 15 March 2022].
 Hoest, C., Seidman, J., Pan, W., Ambikapathi, R., Kang, G., Kosek, M., Knobler, S., Mason, C. and Miller, M., 2014. Evaluating Associations Between Vaccine Response and Malnutrition, Gut Function, and Enteric Infections in the MAL-ED Cohort Study: Methods and Challenges. Clinical Infectious Diseases, [online] 59(suppl_4), pp.S273-S279. Available at: <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4204607/> [Accessed 15 March 2022].
 Shinsugi, C. and Mizumoto, A., 2021. Associations of Nutritional Status with Full Immunization Coverage and Safe Hygiene Practices among Thai Children Aged 12–59 Months. Nutrients, [online] 14(1), p.34. Available at: <https://www.mdpi.com/2072-6643/14/1/34> [Accessed 15 March 2022].
 Ruck, C., Odumade, O. and Smolen, K., 2020. Vaccine Interactions With the Infant Microbiome: Do They Define Health and Disease?. Frontiers in Pediatrics, [online] 8. Available at: <https://www.frontiersin.org/articles/10.3389/fped.2020.565368/full#h7> [Accessed 8 April 2022].
 Zimmermann, P. and Curtis, N., 2018. The influence of probiotics on vaccine responses – A systematic review. Vaccine, [online] 36(2), pp.207-213. Available at: <https://pubmed.ncbi.nlm.nih.gov/28923425/> [Accessed 8 April 2022].
 Chen, J., Vitetta, L., Henson, J. and Hall, S., 2021. The intestinal microbiota and improving the efficacy of COVID-19 vaccinations. Journal of Functional Foods, [online] 87, p.104850. Available at: <https://www.sciencedirect.com/science/article/pii/S1756464621004990> [Accessed 8 April 2022].
 Unicef.org. 2021. “Breastfeeding acts as a baby’s first vaccine, providing critical protection from diseases and death” - UNICEF. [online] Available at: <https://www.unicef.org/iraq/press-releases/breastfeeding-acts-babys-first-vaccine-providing-critical-protection-diseases-and> [Accessed 11 April 2022].
 Dòrea, J., 2009. Breastfeeding is an essential complement to vaccination. Acta Paediatrica, [online] 98(8), pp.1244-1250. Available at: <https://pubmed.ncbi.nlm.nih.gov/19594471/> [Accessed 11 April 2022].
 Perl, S., Uzan-Yulzari, A., Klainer, H., Asiskovich, L., Youngster, M., Rinott, E. and Youngster, I., 2021. SARS-CoV-2–Specific Antibodies in Breast Milk After COVID-19 Vaccination of Breastfeeding Women. JAMA, [online] 325(19), p.2013. Available at: <https://jamanetwork.com/journals/jama/fullarticle/2778766> [Accessed 11 April 2022].
 Grantham-McGregor, S., Walker, S. and Chang, S., 2000. Nutritional deficiencies and later behavioural development. Proceedings of the Nutrition Society, [online] 59(1), pp.47-54. Available at: <https://www.cambridge.org/core/services/aop-cambridge-core/content/view/9CBDE50E1D3566212208440D1B952409/S0029665100000069a.pdf/nutritional-deficiencies-and-later-behavioural-development.pdf> [Accessed 7 July 2021].
 2021. [online] Available at: <https://www.who.int/news/item/12-09-2019-vaccination-european-commission-and-world-health-organization-join-forces-to-promote-the-benefits-of-vaccines.> [Accessed 11 March 2022].
 Oyo-Ita, A., Wiysonge, C., Oringanje, C., Nwachukwu, C., Oduwole, O. and Meremikwu, M., 2016. Interventions for improving coverage of childhood immunisation in low- and middle-income countries. Cochrane Database of Systematic Reviews, [online] Available at: <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4981642/> [Accessed 11 March 2022].
 Unicef.org. 2021. Immunization. [online] Available at: <https://www.unicef.org/immunization> [Accessed 11 March 2022].