Drugmakers are hustling to make a vaccine to counter the rapidly spreading respiratory virus that has sickened at least 1,975 people in China and five in the United States.

The National Institutes of Health has partnered with a Boston-area company, Moderna, on a vaccine targeting the novel coronavirus. A Pennsylvania biotechnology company, Inovio, also secured a $9 million grant from Norway-based Coalition for Epidemic Preparedness Innovations to develop a vaccine. The company already is developing a vaccine for Middle East respiratory syndrome, or MERS, another type of coronavirus.

Officials with the National Institute of Allergy and Infectious Diseases say they can quickly develop a vaccine because Chinese scientists rapidly sequenced the virus’s genome.

“The agency has the funding and technology,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. “Barring any bureaucratic or regulatory holdups, which I don’t think will happen, we can almost certainly get into phase one in three months.”

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Even if the vaccine is tested rapidly, it might not come in time to slow the outbreak. Public health efforts to limit the spread of the virus and treat those who are infected will have a more immediate benefit.

The virus, which originated in the central city of Wuhan, has spread to surrounding regions in China and South Korea, Japan, Singapore, Hong Kong, Macao, Taiwan, Thailand and Vietnam.

The first U.S. case, a Washington state man in his 30s, was diagnosed Tuesday. A second case, a woman in her 60s, was reported Friday in Chicago. Three more cases were confirmed Saturday and Sunday in California.

The federal Centers for Disease Control and Prevention is coordinating efforts to limit the virus's spread, limiting flights from the region to five U.S. airports and screening 2,000 returning travelers as of Friday. At least 63 potential cases are under investigation in 22 states, and 11 had been confirmed negative, officials said.

The U.S. State Department advised travelers to avoid the central Chinese province of Hubei, home to Wuhan.

How a vaccine would be developed

As public health officials work to limit the spread and get medical care to those in hard-hit regions, scientists, government and drugmakers are racing to develop new vaccines and other drugs.

Fauci said scientists need to secure samples of the coronavirus from China so they can begin testing. He is optimistic Chinese authorities will soon allow release of the crucial samples, which also can be used to develop other drugs such as monoclonal antibodies.

Once the agency obtains samples, scientists can test the vaccine in animals, then in humans. An initial “phase one” study of about 20 patients would evaluate whether the vaccine is safe. Officials would then need to decide whether to pursue a larger study to test the vaccine’s effectiveness.

“Getting the vaccine candidate in the laboratory is the shorter and easier part,” said William Schaffner, a Vanderbilt University School of Medicine professor of preventive medicine. “It is testing it in people to make sure it’s safe and it’s likely to work that takes much more time and much more money.”

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Researchers have a head start from work on vaccines for other coronaviruses responsible for past outbreaks of severe acute respiratory syndrome, or SARS, and MERS.

Researchers know the similarities shared by the family of viruses, but "the parts that are different from virus to virus are those critical parts that are important for protection,” Fauci said.

His agency will develop the vaccine using a technology called messenger RNA platform, which instruct cells to make proteins. The newer technology will allow the agency to develop one more quickly. During the SARS outbreak in 2002-2003, it took about 20 months to prepare a vaccine for clinical trial, Fauci said.

The SARS vaccine has not been needed because the virus has not returned, but it is available if it does.

Developing a universal vaccine for the next outbreak

Another possibility, Fauci said, is to develop a universal vaccine to attack all types of coronaviruses, a sort of insurance policy when the next one is transmitted from an animal to a human.

For now, the agency has prioritized development of a universal flu vaccine, which gets less attention even though the more common illness is far more lethal than the coronavirus. Today, flu vaccines are made each year and tailored to match strains scientists project will circulate before the seasonal flu season begins.

CDC estimates the flu this season has sickened at least 15 million and caused 8,200 deaths, an illness that dwarfs the harm from coronavirus.

"In comparison to flu, the impact on the new coronavirus in the United States will be trivial," Schaffner said. "It’s new, it’s novel, it’s mysterious. It started in an exotic place. We are all energized. So it is no great surprise the general public is interested."

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