Scientists at Greffex, a Houston, Texas-based genetic engineering company, claim they've created a coronavirus vaccine.

The company told the Houston Business Journal that it had completed development of the vaccine and it is ready for animal testing and review by US regulators.

It comes after UK scientists announced they'd begun testing their shot, and researchers at the University of Texas at Austin announced they'd made compound they believe can serve as a vaccine.

Countless scientists around the world are racing to the do the same, though they're taking many different approaches.

Developing a vaccine, however, is just the first step toward distributing one. Most estimates suggest that from, testing and production could take between 18 months and two years, though Greffex has not announced its timeline.

© Provided by Daily Mail A Houston, Texas, genetic engineering company says that it's created a vaccine to prevent the coronavirus (pictured in recolored electron microscope images) that's ready to test in animals

Greffex said that, for the sake of safety, its scientists did not use any form of the coronavirus itself - either live or inactivated - to make its vaccine.

Most vaccine contain either live attenuated virus or an inactive form of the pathogen.

However, the coronavirus is so poorly understood, has spread so quickly and has killed enough people that scientists at Greffex did not want to risk exposure that could trigger the life-threatening illness known as COVID-19.

Scientists at the genetic engineering company have instead built their vaccine on an adenovirus.

Adenoviruses are among the most common causes of viral respiratory infections, accounting for between two and five percent of colds.

They're also widely used in the making of vaccines.

Other companies are basing their candidate vaccines on ones previously developed during the SARS outbreak but abandoned once the virus subsided within six months.

Scientists at the University of Texas, Austin, had to recreate a molecule that makes up the spike protein on the surface of the coronavirus (now know as SARS-CoV-2) in order to create a three-dimensional map of the structure.

And the compound they made to do so itself can work as a vaccine, triggering an immune response to the virus, they believe.

Like the UT Austin team and their collaborators at Moderna Therapeutics, the Greffex team believe that their process for production is among the fastest available to produce a vaccine.

'The trick in making a vaccine is can you scale the vaccine that you’ve made to be able to make a certain number of doses, can you test the vaccine quickly and efficiently and then can you get it into patients - and that’s where we have an edge as well on the other companies that are out there,' Greffex CEO John Price told KHOU.

'And that’s where we have an edge as well on the other companies that are out there.'

Greffex's vaccine comes after the National Institutes of Health (NIH) gave the company a grant of up to $18.9 million to develop a 'plug-and-play' platform that would let it add a few specific ingredients, so to speak, to it's basic formula and quickly design vaccines.

Now that the candidate vaccine is read, they'll have to test it in animals, then begin phase 1 clinical trials in people, followed by another two phases of human trials, and ultimately Food and Drug Administration (FDA) approval.

Vaccines can take upwards of a decade to develop, from soup to nuts.

Even with all the expediting possible, testing required by the FDA is thorough and time consuming, so fast production of a vaccine will still like take 18 months to a year.