A top U.S. scientist behind groundbreaking research in cancer and HIV/AIDS warned that a vaccine for the coronavirus may never be found as the number of global COVID-19 infections surged past 5 million Thursday.
The scientist, William Haseltine, who has also worked on human genome projects, said that while a COVID-19 vaccine could be developed, "I wouldn't count on it." Instead, he told Reuters, countries that are beginning to reverse lockdown measures need to lean on careful tracing of infections and strict isolation measures to control the spread.
Such an approach has proved successful in some countries that have minimized the spread, but worldwide, the numbers continue to climb. More than 328,000 people had died because of the virus as of Thursday morning, while 5,001,494 had been infected, according to Johns Hopkins University.
The U.S. accounts for 95,003 of those deaths and more than 1.5 million cases, according to NBC News' tracking Thursday night — the highest reported totals for any country.
A race to develop a vaccine is underway at labs around the globe. Trials are underway at Oxford University in England that if successful could mean a vaccine by September, while the Massachusetts-based company Moderna announced this week that its first round of testing of a vaccine were strong enough to move ahead to a larger second trial.
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The developments are crucial. The World Health Organization announced Wednesday that the world had its highest increase in reported cases in a 24-hour period, with 106,000 new infections.
However, Haseltine cautioned that vaccines developed for other types of coronavirus in the past failed to protect mucous membranes in the nose, where the virus typically enters the body. And while tests of some experimental COVID-19 vaccines on animals were able to reduce the viral load in organs like the lungs, the infections remained.
Haseltine said that even without an effective treatment or vaccine, the virus can be controlled by identifying infections and finding and isolating people who have been exposed. People should also wear masks, wash their hands, clean surfaces and keep a distance, he said.
For treatment, there are more promising developments. Antibody-rich plasma donated by people who have recovered from COVID-19 is being delivered to sick patients, and drugmakers are working to produce refined and concentrated versions of that serum, known as hyperimmune globulin.
Haseltine said he believes the products are among the trials "where the first real treatments are going to be."
The Centers for Disease Control and Prevention quietly released a document this week on its website outlining recommendations for reopening restaurants, mass transit, schools and child care programs across the U.S.
It cautioned that not all businesses and institutions should reopen yet — depending on the number of coronavirus cases in their areas — and instead recommended an approach in three phases, each more permissive than the last, provided rates of transmission do not spike.
China and South Korea — among the countries best at curbing infection rates, according to Haseltine — began easing lockdowns last month, although China re-implemented lockdowns in some areas last week because of upticks in infections.