Scientists are racing to identify and test possible vaccines for COVID-19 as nations grapple with the economic and societal consequences of the virus lockdowns.
Seth Berkley of Gavi, the vaccine alliance, said the international community must ensure all countries will have access to any potential vaccines, regardless of their wealth.
"This is a global problem that needs a global solution and we have to all work together,” he said.
He spoke ahead of a virtual summit hosted by Britain on Thursday, where Gavi hopes to raise at least $7.4 billion to continue vaccination programmes against diseases like measles, polio and typhoid that have been severely disrupted by the pandemic.
The meeting will also see Gavi and its partners launch a financing drive to purchase potential COVID-19 vaccines, scale up their production, and support delivery to developing nations.
The fundraising goal for COVID-19 is $2 billion, although Berkley said it was an initial sum as they kickstart negotiations with manufacturers and could go up "substantially”.
The meeting comes as the pandemic exposes new ruptures in international cooperation.
US President Donald Trump last week announced he would pull out of the World Health Organisation and there are fears America may use its economic clout to buy up vaccines.
Berkley said that countries needed a "different mindset”, adding that sharing access to drugs was not just a humanitarian and equality issue, but a global health security one.
"Nobody is safe unless everybody is safe. We saw the virus move from somewhere around Wuhan to 180 countries in less than three months, including islands and isolated areas,” he said.
‘Perfect storm’
The World Health Organisation, UN children’s agency UNICEF and Gavi warned last month that the pandemic had hindered routine immunisation services in nearly 70 countries, affecting around 80 million children under the age of one.
Polio eradication drives were suspended in dozens of countries, including those still struggling with the debilitating illness, while measles vaccination campaigns were also put on hold in 27 countries, UNICEF said.
Recent Gavi-supported modelling from the London School of Hygiene and Tropical medicine estimated that for every COVID-19 death prevented by halting vaccination campaigns in Africa, up to 140 people could die from vaccine-preventable diseases.
Berkley said the situation was improving, with new guidance on how to carry out immunisation campaigns safely.
But he said locating all the children who missed out on vaccines before new outbreaks emerge will be a "real challenge”.
Thursday’s funding drive is for a five-year period in which the organisation aims to reboot halted programmes in the countries it supports — allowing them to access vaccines at a much reduced cost — with the goal of reaching some 300 million children.
Berkley said he was "cautiously optimistic” that the target would be reached, with more new countries pledging donations despite the economic strains of the pandemic.
Recalling past episodes when vaccine work was stalled by the outbreak of diseases such as Ebola and SARS, another coronavirus, he urged nations to move beyond "boom and bust” cycles of crisis planning.
"I don’t think this coronavirus is going to go away like SARS did,” he said.
He also warned of an "unprecedented” level of rumour and conspiracy theory around vaccinations, particularly from the northern hemisphere.
"Distrust between people in their government, the rumours and the intentional spread of false information is not only at an all time high, but it also is being amplified by social media tools that didn’t exist 20 years ago,” he said.
"So we have almost a perfect storm of problems.”