When Abhijit Banerjee found out that he had won the Nobel Prize in Economics in 2019, he was reading a book. Two years earlier, Kazuo Ishiguro, honoured with the Nobel Prize in Literature, was in the middle of writing an email when he heard about his triumph. Malala Yousafzai, the youngest Nobel Peace Prize laureate, was in chemistry class when the news broke in 2014 — her school teacher paused the lesson to let her know she had just made history.
For Ananda Sankar Bandyopadhyay, recipient of the IVI-SK Bioscience Park MahnHoon Award, often referred to as the “Vaccine Nobel”, the defining moment came during a holiday in Kolkata, when he was strolling down Park Street with his family.
“I was showing them my college [St. Xavier’s College, Kolkata] and around when the call came from the chair of a prestigious international selection committee. I couldn’t believe it. I thought it was a spam call,” recalls Bandyopadhyay during an interaction with My Kolkata at Pico, a few weeks after collecting his prize in Seoul.
The IVI-SK Bioscience Park MahnHoon Award recognises global pioneers in vaccine science. In 2025, it went jointly to Bandyopadhyay, presently the deputy director of the polio programme at the Gates Foundation, and his Belgian collaborator, Pierre Van Damme, for their groundbreaking work on vaccine research. This includes their role in the development and rollout of the novel oral polio vaccine type 2 (nOPV2) — a vaccine that is helping the world take decisive steps towards eradicating a devastating disease.
Bandyopadhyay with his fellow winners, including Pierre Van Damme (extreme right)
Bandyopadhyay’s award is, in many ways, a tribute to teamwork — a theme he himself reiterates. Bandyopadhyay, 46, met Van Damme serendipitously in Brussels in 2014. At the time, Bandyopadhyay was grappling with a seemingly insurmountable challenge: how to test a novel polio vaccine that could not be used outside a secure containment setting due to global restrictions.
The solution was born over a chance breakfast in Brussels. “One of my mentors, Ralf Clemens, connected me with Pierre and said, ‘Why don’t you just talk with each other?’” says Bandyopadhyay. Over coffee and conversation, the two conceived the idea of building a fully contained “village” where volunteers could safely receive and be monitored after vaccination.
Van Damme turned that vision into reality, constructing Poliopolis in the parking lot of Antwerp University Hospital — a first-of-its-kind containment facility. “It resonated with the global health community,” describes Bandyopadhyay. Over time, the concept evolved into Vaccinopolis, a permanent multi-storey facility contributing to pandemic preparedness and vaccine development worldwide, underlining the power of open, organic partnerships.
‘Countries like India are polio free, but not polio risk free’
The urgency behind developing nOPV2 stemmed from a paradox. Wild poliovirus types 2 and 3 have been globally eradicated, and type 1 remains endemic only in parts of Pakistan and Afghanistan. But in areas with low vaccination coverage, variants of the virus — technically vaccine-derived polioviruses — continue to circulate. “They never emerge in areas where you have high vaccination coverage,” explains Bandyopadhyay. “I keep saying… they are low vaccination-derived polioviruses.”
What sets nOPV2 apart is that it is genetically engineered to be more stable and less likely to mutate into harmful variants. Its success has been transformative. Since its rollout in 2021, nearly two billion doses have been administered across more than 40 countries. “In most instances, it has decisively stopped the circulation of this specific variant poliovirus types,” says Bandyopadhyay.
India, too, has played a vital role. Hyderabad-based Biological E became the second WHO pre-qualified manufacturer of nOPV2 in late 2024, helping diversify global supply. “If you’re seeing outbreaks in 40-ish countries, reliance on one manufacturer is very problematic,” notes Bandyopadhyay.
Yet, despite the achievement, Bandyopadhyay stresses that “countries like India are polio free, but they’re not polio risk free.” Recognition through awards such as Bandyopadhyay’s helps spotlight the ongoing fight: “It brings the attention back and reminds people that the job is not done.”
“People should be desperate when it comes to stopping outbreaks and diseases,” says Bandyopadhyay
“I use this term: desperation. People should be desperate when it comes to stopping outbreaks and diseases,” says Bandyopadhyay, calm yet urgent in his words. Early in the nOPV2 journey, not everyone grasped the immediacy of the threat. “We didn’t succeed right away in bringing all the key partners along… there were questions as to whether a new vaccine should be considered at all… that was one of the challenging aspects.”
When it comes to vaccination, scale brings its own surprises. “We thought this would be a ‘boutique vaccine,’” admits Bandyopadhyay. Instead, soaring demand required unprecedented manufacturing and delivery logistics, often to some of the world’s most challenging regions — Northern Nigeria, Eastern DRC, Somalia.
The outbreak of Covid-19 introduced fresh complications by disrupting vaccine supply chains and policymaking, even as polio did not pause for the pandemic. In a powerful twist, nOPV2 became the first vaccine authorised under the WHO’s Emergency Use Listing pathway, paving the way for Covid-19 vaccines to follow.
Turning opponents into advocates
The grandfather in Kultali with his polio-affected grandchild
Speaking to Bandyopadhyay crystallises not just the science behind vaccination, but also the stories. And there’s no shortage of those, given Bandyopadhyay’s field experiences during his stint with the WHO. One such account from 2008 in Kultali, South 24-Parganas, stands out.
A polio case had surfaced in an area not considered high-risk for polio transmission. “When you see a confirmed paralysed child with polio virus, it means hundreds, if not thousands, of individuals around that paralysed case are also infected, because polio is a subclinical disease. Not everybody who has the virus will show up with paralysis. So, even a single detection constitutes a public health emergency,” remembers Bandyopadhyay.
On investigation, Bandyopadhyay discovered widespread vaccine refusal rooted in distrust. “The sense that I got was of the locals being alienated. The essential message from the community was: ‘You folks didn’t quite come to us when we were suffering from other diseases. And now suddenly all of you are here.’”
Through painstaking dialogue — particularly with the affected child’s grandfather, a staunch vaccine opponent — Bandyopadhyay and the team of health workers helped turn mistrust into advocacy. “After multiple conversations, his opposition gradually melted. He became like family… The first vaccination campaign after that was a sight to behold. The grandfather himself was taking the vaccine boxes around and vaccinating children.… Kultali never had a polio case again.”
‘Intuitive inclusiveness’ and the role of AI in vaccines
Bandyopadhyay welcomes the role of AI in vaccination, but with caution
Today, based in Seattle and leading the technology, research and analytics team at the Gates Foundation, Bandyopadhyay brings a deeply rooted Indian perspective to his global work.
One key trait he credits to his upbringing in Kolkata is “intuitive inclusiveness”. “If I’m sitting with a group of people from different parts of the world… I can develop a connection by taking in all the inputs and forming a coherent, collective way of functioning.” Growing up in Kolkata in the ’90s, Bandyopadhyay’s love for A.R. Rahman’s music — despite language and cultural differences — helped shape this instinct. “You celebrate something completely different… That sense of inclusiveness has to be organic and intuitive, not something you consciously have to manufacture.”
As vaccination science enters a new era, Bandyopadhyay wants the lens of inclusivity to shine on Artificial Intelligence (AI). An increasingly larger role for AI in vaccine development is something Bandyopadhyay welcomes, but with caution.
According to Bandyopadhyay, AI-powered chatbots could transform vaccine awareness for both parents and health workers. On the scientific front, AI is revolutionising understanding of protein folding and accelerating vaccine design. “This is brand-new thinking… I think both the scientific development and delivery access [in vaccination] can hugely benefit from the application of AI.”
Does Bandyopadhyay feel AI can soon take the lead in coming up with a new vaccine?
“Absolutely. In fact, we just initiated an investment from the Gates Foundation to explore whether AI can inform the development of yet another polio vaccine.”
However, representativeness remains key. “Many of the knowledge inputs that go into some of these AI-based tools are skewed towards a particular language, English, and a particular region of the world, the global north,” warns Bandyopadhyay. For AI to truly serve global health, Bandyopadhyay wants AI to reflect diverse languages and realities.
‘I’d get A.R. Rahman to compose an anthem for global vaccination!’
A.R. Rahman tops the list of public personalities Bandyopadhyay admires
For all his scientific achievements, Bandyopadhyay remains a patient listener — something he sees as vital to staying updated in a rapidly evolving field. He also encourages nimbleness of mind: “Knowledge building and knowledge expansion are about being adaptable, being open with the people you interact with.”
This takes on greater relevance in a deglobalising world, where political currents are sharply reorienting how openness is perceived across continents and cultures. In this context, Bandyopadhyay has a clear message: “The viruses that we are fighting… they are, in one way, more noble than we are. They don’t discriminate based on political affiliation, caste, creed, religion, or passport status. All that matters is whether you have protective immunity or not. Viruses are a notorious force that operate effectively as a group. Unity is the key to fighting such viruses.”
Before he takes his leave at Pico, having enjoyed his cortado and fish and chips, Bandyopadhyay has a final question to answer. If he had unlimited resources at his disposal, what would he do to accelerate immunisation coverage worldwide?
For once, Bandyopadhyay takes the mischievous route: “I’d get A.R. Rahman to compose an anthem for global vaccination!”
On reflection, Bandyopadhyay’s answer feels more serious. His twin passions, vaccination and music, stem from the same moral mandate of bringing people together. Of ensuring a better life through the best that science and the human spirit have to offer.