Guinea's Ebola outbreak is nearly under control, as the number of new cases have fallen dramatically, the nation's health ministry said Tuesday.

The deadly virus, which has no known cure, spread from a remote corner of Guinea into neighboring Liberia, killing about 130 people, according to a Reuters report.

While these West African nations were struggling to contain the disease the United States stepped in an increased lab testing as well as restricted travel.

"The number of new cases have fallen rapidly," said spokesman Rafi Diallo, with 197 confirmed cases, according to the World Health Organization's (WHO) latest report.

Diallo said that the newest cases being monitored, around 400, were people who aren't sick, but came in contact with already-infected patients.

Ebola haemorrhagic fever, as it's formally known, kills 90 percent of its victims, WHO states. The virus spreads through direct contact with bodily fluids, including blood, feces or sweat.

The organization also said earlier this month that it would take two to four months to rein in the Ebola virus, which has been one of the most challenging outbreaks it has ever come up against.

However, Diallo said Guinea had recorded 37 cases of people recovering from the disease.

"Once we no longer have any new cases ... we can say that it is totally under control," he added.

Meanwhile, the US Department of Defense on Monday opened a laboratory on the outskirts of Monrovia to tackle the cases in Liberia. Guinea's neighbor reportedly has at least 13 deaths from 26 confirmed and suspected cases of Ebola.

Samples also tested in the West African nations of Mali, Ghana and Sierra Leone have been negative so far.

But scientists are honing in on ways to stop this disease in its tracks, with several promising vaccines and medications under development, said Dr. Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases (NIAID), according to HealthDay.