Science can and does change humanity. Yet while we live in an age of extraordinary advances, profound health challenges remain. Global health emergencies such as rapidly rising drug-resistance, epidemic threats from diseases known and unknown, mental health, and the escalating climate crisis are a threat to us all.

Science gives us the tools to deal with these challenges, and it can save lives. But no matter how exciting the treatment, clever the delivery method, or robust the science, we will only see a positive impact if the people who stand to benefit feel engaged.

Wellcome Global Monitor interviewed 140,000 people from over 140 countries to uncover public attitudes to science and health - and the results have highlighted the central role of trust.

It reveals that people in Africa have the highest confidence in vaccines globally, with around three-quarters (75%) of the population strongly agreeing that vaccines are safe and effective. Despite this, trust and engagement with science and health is low across the continent.

Close to one-third of people in Africa have no confidence in hospitals and health clinics, and 16 of the 20 countries in which confidence in doctors and nurses is weakest are in Africa. A quarter of people have low trust in scientists. More than one-third feel personally excluded from science, and one-in-four people believe that science benefits very few people in their country.

Globally, people who believe science benefits most people in their society are six times more likely to have higher trust in scientists than those who believe it benefits very few. And high trust in scientists is linked to high trust in health professionals and national institutions.

Low trust can raise serious – even life-threatening – risks. In the Democratic Republic of Congo, decades of war, insecurity and neglect have ravaged trust in institutions across the east of the country. Dangerously low levels of trust, combined with the spread of misinformation, have made the response to the Ebola epidemic incredibly challenging. A quarter of respondents to a recent Lancet study did not believe that Ebola was real, and attacks on health workers are a common occurrence. Since January, the WHO has recorded around 250 healthcare attacks in the DRC, resulting in seven deaths and 66 injured healthcare workers and patients.

Thanks to research, we are now able to both protect from Ebola through vaccination and have potentially found a breakthrough for treating Ebola. This is an incredible achievement and means we can start to think of Ebola as preventable and curable. But there is no room for complacency.

We urgently need to work with communities to rebuild their trust. And as public health advances and we enter the Fourth Industrial Revolution, this means building trust in new technologies, and ensuring communities are both at the heart of work and have ownership of new approaches. Science can only thrive and have a positive impact with the support of the societies in which it works – and the advances, new cures and treatments must be equally available to all who can benefit, regardless of their ability to pay.

Trust in national institutions, science and healthcare are linked and cannot be viewed in isolation. When confidence in one is lost, confidence in the others tends to suffer as well.

Wellcome Global Monitor’s findings from Rwanda highlight what can be achieved through effective community engagement. Along with Bangladesh, Rwanda has the highest confidence in vaccines in the world – virtually the entire population agrees that vaccines are safe, effective and important for children to have. At 97%, people in Rwanda also have the highest trust in their healthcare system compared to a global average of 76% and 69% across Africa.

Twenty-five years ago, we saw a very different picture. Following the Rwandan genocide of 1994, which left behind a failed state and a traumatized population with little trust in local or international institutions, government and international partners tried to rebuild trust through grassroots engagement with local communities. Today’s high trust levels are testament to those efforts; the country now has 95% immunisation coverage and will likely be the first African country to wipe out cervical cancer.

Nigeria also has among the highest confidence in vaccines in the world, with 97% of the population agreeing that vaccines are important for children to have and 91% agreeing they are safe. While this survey does not provide all of the answers, Nigeria’s high confidence levels likely reflect years of effective engagement at the grassroots level. In 2003, at the height of the boycott of polio immunisation, the Global Polio Eradication Initiative Partners engaged with faith leaders and communities in northern Nigeria. By learning about the production of the polio vaccine, faith leaders - highly trusted in the community - could see it is safe. This practice continues today, and UNICEF describes the collaboration as game-changing.

Policymakers, practitioners and civic leaders should pay close attention to the Africa findings from this survey. According to the IMF, around half of the 40 fastest-growing economies are in Africa. Health and wellbeing underpins and encourages economic growth in every society; if the world’s youngest continent, where 60% of people across the continent are aged 25 or younger, is to have a prosperous, sustainable future, health care must be prioritised, with no-one left behind.

The reasons behind trust are complex and multifaceted, and a single survey cannot explain why people feel the way they do. But we can see that trust in national institutions, science and healthcare are linked and cannot be viewed in isolation. When confidence in one is lost, confidence in the others tends to suffer as well.

If we want science to have maximum impact and help us all achieve better public health outcomes, we must remember the central role of trust.