Dr. Seth Berkley is regarded as one of the most influential people in the world, a "visionary" and absolutely on the frontline in fighting, controlling and managing global health threats, from flu to HIV.
Now, even though he's been doing this for decades with such prominence that he was on the Newsweek front cover nearly 20 years ago, the very present COVID-19 crisis creates some new problems.
In his nine years as the head of GAVI, the Vaccine Alliance, he has worked towards the idea that everyone, particularly in developing countries, should have access to the same vaccines and immunizations rather than just the richest countries and populations. This is more true than ever for COVID-19.
He tells Newsweek in an exclusive interview that there is still a long way to go in the fight against COVID-19 and making sure that it is not just a solved problem in the richest nations.
"We have no idea whether any of these vaccines will work, so it's impossible to give a timeline," Dr. Berkley told Newsweek when asked how far away the world was from finding a vaccine.
"From a planning point of view, we have six candidates now in trials. That tells you that we're going to start getting efficacy data in the third quarter, perhaps in the fourth quarter, they may all be negative or we may start to get some positive signals so it's important that we start planning for that."
President Trump recently announced that he had reached a deal with biotechnology company Moderna to purchase 100 million doses of its experimental vaccine for $1.5 billion, with Boris Johnson describing the search for a vaccine as the "the most urgent shared endeavor of our lifetimes".
This "shared endeavor" is close to Dr. Berkley's heart.
He says that major pharmaceutical companies should put global good ahead of profit when it comes to a COVID-19 vaccine and chances of success for countries deciding to go it alone in the search for a vaccine "are slim".
Despite all the regulatory tests and licensing work still to do even with successful trials, Berkley implores countries to join coordinated efforts. Otherwise, he says, they face the stark reality of being at the back of the queue if and when one does become available.
He also condemned deliberate partisan attempts at misinformation and there was a lot of information needed to verify Russian President Vladimir Putin's claim that the country had developed vaccine ready for use.
With over 750,000 dead across the world, and the global economy thrown into turmoil, the stakes could not be higher.
But big challenges are something Dr. Berkley has a great deal of experience in.
After training as a physician at Brown and Harvard, spending time as an epidemiologist in Brazil and Uganda, witnessing Aids develop in the 1980s, he took on - at the age of 40 - the job of trying to make sure the then (and still now) undiscovered Aids/HIV vaccine could be delivered to all.
Then, in 2011, he took control of GAVI, the Vaccine Alliance, which had the Bill and Melinda Gates Foundation as founding partners, to continue that work.
The Gates Foundation alone has donated $4.1bn to this work so far, though much of GAVI's funding comes from nation-states.
But how can anyone realistically ensure that the COVID-19 vaccine is made available to all, given that cases of polio are still recorded in some parts of the world?
GAVI has recently established its COVAX facility in partnership with the World Health Organization (WHO) and the Coalition for Epidemic Preparedness Innovations (CEPI), which aims to ensure every country, particularly poorer ones, can get fair and equitable access to a COVID-19 vaccine.
The aim is to deliver two billion safe doses of vaccine by the end of 2021, with wealthier countries pooling their resources alongside agreements with lower-income countries in a bid to find a cure.
The benefit of this approach rather than going it alone, a GAVI spokesperson has told Newsweek, is that should a country fail in its own agreement, then at least signing up to a more coordinated approach between several countries pooling their resources, will mean every country gets access to a vaccine should one become available.
The plan is to purchase vaccines for all, providing doses for an average of 20 percent of each country's population, focusing on health care workers and the most vulnerable groups.
Further doses will be made available based on financing, country need, vulnerability and potential threat.
However, Dr. Berkley concedes that it won't be possible to vaccine everyone.
"No vaccine is 100 percent effective nor are we able to get vaccines to 100 percent of the population," he said.
"If there is a raging pandemic going on in other countries you can't go back to normal commerce, trade, tourism, travel, all of the things that make the global economy."
GAVI believes that vaccinating 20 percent of the population in all countries who participate in its scheme will cover the most vulnerable people and healthcare workers and, by doing so, suppress the transmission of the disease.
The U.K. is among those countries who have decided to forge agreements on their own with companies in a bid to find a vaccine, signing four separate agreements, while Trump has openly talked about an "America first" approach to the vaccine.
Doesn't this undermine GAVI's efforts at a collaborative approach, when some of the world's most powerful states have decided to go it alone in the search for the vaccine?
Dr. Berkley says: "Even for countries that have done their own bilateral deals, given the probability historically of vaccines succeeding of less than 10 percent, if you've done a deal, maybe it will work maybe it won't. If it doesn't you're at the back of the queue.
"We've suggested for those countries, join the facility, if your vaccine works great, if not, then we give you the insurance to make sure you will have access to a product."
A recent survey found that one-in-three Americans would not get a COVID-19 vaccine, with the figure standing at one in four in the U.K.
With such skepticism and the spread of fake news about vaccines, how does GAVI intend to tackle that to ensure global vaccination?
Dr. Berkley says: "I do think we need to take some of those polls with a grain of salt, we should take them seriously and work to make sure that people are comfortable are reassured and have the facts.
"I think part of this has also has been a response to claims that have been made incorrectly about different interventions and a sense that this may become political and that makes people nervous."
He hopes that people will change their minds once they see vaccines going through regulatory processes, trialed and then being used.
"This is a dangerous time a lot of this stuff has become quite partisan," he said.
"We have a lot of misinformation that is being spread intentionally as well as from people who just don't know any better and I think we need to take it seriously and try to have positive and factual information flowing and try to dampen down intentional misinformation."
The CEO of pharmaceutical company Pfizer has already said that he wants to make a profit from any potential vaccine, an argument that Dr. Berkley says he can sympathize with when it comes to smaller companies.
"We need to be honest, there's a huge amount of public investment going into vaccines and that ought to be taken into account when one thinks about how these products are priced and what we need to do," Dr. Berkley says.
"It is a societal decision that said we want vaccine companies and pharmaceutical companies to be for-profit entities, in the old days there used to be states entities that provided these products and then the determination was made politically that there was efficiency in the private sector and we would make sure that was the mechanism.
"You can't turn around then and say to them, well we made that decision but now we think you should become non-for-profit entities."
When it came to larger pharmaceutical companies, Dr. Berkley said he could see a different argument being made.
"I think for large companies that have adequate balance sheets, there is an argument to say during a pandemic that we work for the global good and we do it around the cost level," he said.
"I think it's very very hard for small companies if this is their product, I think they probably need to make a modest profit as part of it."
Dr. Berkley also praised the role of Bill Gates not only for being GAVI's single biggest supporter but also for continuing to support its ongoing vaccination programs for a range of other illnesses such as measles and polio.
While much of the world continues to look for a vaccine, Russian President Vladimir Putin recently announced that the country had given regulatory approval to a locally developed COVID-19 vaccine.
It's a claim Dr. Berkley is not so sure about.
"We don't have public, published information on efficacy or safety of this product," he said.
"It may be that there's some data we don't know about but in general what's very important is that vaccines go through a well-oiled and recognized process for evaluation and safety and ultimately registration."
"My understanding from the media is that they [Russia] are starting an efficacy trial now so it hasn't been through an efficacy trial and normally that would not allow a stringent regulatory authority to approve it.
"If there is some efficacy data we don't know about, we'd love to see it."
He reiterated his call for countries to put self-interest aside and work together.
"In a pandemic situation with a virus spreading as quickly as its spreading, having a global view is absolutely critical."
For someone who's spent his working life arguing for a global response to global concerns, he hopes that the world stands up and takes notice.
