Reset vaccine progress to drive global health equity

Forward-looking vaccine research is key to fighting cholera and other life-threatening diseases, writes the Wellcome Trust's Charlie Weller.

Administering the oral cholera vaccine in Bentiu, South Sudan. The disease is rising as global vaccine coverage plateaus. Copyright: UNMISS, (CC BY-NC-ND 2.0)


Despite numerous successful immunisation campaigns, global vaccine coverage has plateaued over the last decade.

The COVID-19 pandemic caused major disruptions to routine and reactive vaccination programmes, alongside the impact of conflict and natural disasters on healthcare systems and decreasing vaccine confidence in some areas.

In 2021, 25 million children missed at least one essential vaccine, and 18 million children in the world received no vaccines at all.

However, this World Immunisation Week it is important to remember that catching up on lost progress is not just about addressing this disruption.

We must also address issues in the research and development system and strive for equity across every stage from vaccine discovery to delivery, to ensure low resource countries, who often face the greatest burden of disease, have access to affordable life-saving vaccines.

The growing cholera threat

Take cholera as an example – a bacterial disease for which vaccine demand far outweighs supplies.

We are currently experiencing a large surge in global cholera cases, with more than one billion people at risk, and the spread is not limited to countries where the disease is already endemic.

Cholera is a marker of inequality, with poverty, unsafe water and poor sanitation leading to more infections.

Natural disasters and conflict can lead to lack of access to clean water and healthcare, factors which are further exacerbated by climate change – including high temperatures, extreme weather, floods and the displacement of affected communities.

The priority for savings lives is timely access to simple oral rehydration therapy, while vaccines play a critical role in controlling and preventing outbreaks.

Pre-emptive action

Oral cholera vaccines have been used in immunisation campaigns to prevent and react to outbreaks for the last three decades. However, our current reliance on a single manufacturer is dangerous, significantly impacting our ability to respond to outbreaks.

In 2022, the global cholera vaccine stockpile was 36 million doses, while demand exceeded 70 million. In the first quarter of 2023, 11.7 million doses have been requested.

To manage this demand, the World Health Organization has temporarily moved to a one-dose strategy to react to outbreaks. This emergency response is critical to save lives but reflects a wider global health issue – the failure to act before an infectious disease escalates.

A forward-looking research and development ecosystem is key to effectively tackling the urgent global health threat of infectious diseases like cholera.

We need to know how to effectively use the tools we already have, while strengthening a system that drives innovation to improve our toolkit against rising cases of existing diseases, or the emergence of new diseases.

£1.3 million funding call

Better detection and surveillance of infectious disease trends and global information sharing is the foundation of preventing outbreaks.

By generating more evidence on how, when and where outbreaks might occur, we can predict potential outbreak hotspots and longer-term vaccine demand to help prioritise effective distribution of limited resources.

Understanding how vaccines work is central to effectively using a limited stockpile and developing new, more effective vaccines. Knowledge about how long immunity to cholera lasts in different age groups, particularly children, means vaccines could be prioritised for those who need them most in the short term, and in the long term more effective, longer lasting vaccines could be developed.

This is why Wellcome has launched a new funding call, offering up to £1.3 million for projects that will strengthen evidence to improve cholera control, including mapping cholera hotspots, and exploring different oral cholera vaccine schedules and the impact on duration of protection.

Tackling vaccine inequality

To address the mismatch between vaccine supply and demand, manufacturing capability within countries with the highest disease burden must be expanded.

Currently, there is a significant imbalance of production capacity towards the global North, meaning countries in the global South have to wait longer to receive crucial doses.

The financing of vaccine manufacturing often focuses on the most commercially attractive diseases, which are often those that impact high-income countries, rather than those that are endemic in low- and middle-income countries.

Wellcome and the Bill and Melinda Gates Foundation have recently supported a licensing and technology transfer agreement between the International Vaccine Institute (IVI) and South Africa-based biopharma, Biovac, to help expand the country’s capability to manufacture the oral cholera vaccine. This will bring help increase vaccine supply in the longer-term to strengthen control the disease in Africa.

Now is the time to drive innovation and global collaboration to make up for lost progress and ensure lasting-protection for children and adults around the world from vaccine-preventable diseases. To achieve global health equity, everyone everywhere must have access to accessible, affordable vaccines.

Written by

Charlie Weller is head of prevention in the infectious diseases area at Wellcome, a UK-based charitable foundation that supports science to solve global health challenges. Since 2016, she led a team to develop new and improved vaccines and antibodies.


This article was originally published by SciDevNet on 24 April 2023.

This piece was produced by SciDev.Net’s Global desk