The world has never watched so closely as scientists work to develop a safe and effective vaccine against Covid-19. While encouraging to see the news about a number of vaccines with high efficacy coming down the pipeline, there are other things that can be done to increase the effectiveness of all vaccines.
Nutrition plays a major role in vaccine efficacy. A recent study in PLOS concluded that “monitoring nutrition may be a practical and low-cost way to impact vaccination outcomes.” The study reflected that good nutrition was key to bolstering the immune response to both the BCG tuberculosis (TB) vaccine and TB treatment itself.
Even prior to the pandemic, we knew that undernutrition in its own right was a killer. The pandemic has compounded the climate crisis, which has led to increased extreme weather events and swarms of locusts that have added further pressure on fragile food systems. Prior to the pandemic, it was estimated that there were 690 million undernourished people. According to the World Food Programme that number could increase by another 132 million by the end of this year.
Central Sahel has been particularly impacted. In mid-October 2020, UN and world leaders gathered to address the mounting humanitarian challenges facing the region, which have been exacerbated by the pandemic. In Burkina Faso for example, one in five children are severely unnourished, food prices are spiking and more than half of the country’s population say that they don’t get enough food.
Growing food insecurity and the climate crisis are threatening to push more families into poverty and drive migration. In this context, vaccines are both harder to deliver and potentially less effective at stimulating an immune response.
It’s not just undernutrition, which affects vaccine efficacy. In the past decade, increasingly sedentary lifestyles and ultra-processed foods with high sugar and fats have helped drive an obesity epidemic that is causing a dramatic increase in hypertension, diabetes type-2 and multiple cancers. Low- and middle-income countries have seen an exponential rise, with 70 percent of individuals with overweight or obesity coming from these countries.
In the pandemic, people with obesity and underlying conditions have been more prone to a serious case of Covid-19 and are at increased risk of dying. Further challenges relate to the concern that when a vaccine for Covid-19 is developed, those with obesity may find it to be less effective. Studies have shown that those people whose immune system is adversely affected by obesity may ultimately lack vaccine-induced immunity.
Taken at scale, undernutrition and obesity both threaten to drive increased mortality during the Covid-19 pandemic and in the long-term they both potentially undermine the efficacy of new vaccines.
It’s a positive development that countries are turning their backs on vaccine nationalism and 184 countries have now joined the COVAX facility so that collectively countries pool risk and then equitably the benefits of vaccine breakthroughs. However, a vaccine will not provide a silver bullet for Covid-19 and the other challenges the pandemic has exacerbated.
As leaders discuss building back better and greener, it’s important that ensuring everyone has access to quality food and nutrition is part of any overarching post pandemic plan.
Work conducted by CGIAR, a global partnership that unites international organisations engaged in research about food security, to develop and promote biofortified food crops that are rich in vitamins and minerals has reached almost 40 million people in low-income countries. Reaching smallholder farming families and other vulnerable groups with these crops helps ensure equality of access to quality food and nutrition and is key to ending the scourge of ‘hidden hunger’.