Science has an answer for that.
According to the Centers for Disease Control and Prevention, about 10 percent of all U.S. cases of Ebola have been diagnosed in people with a genetic mutation associated with the virus.
The CDC estimates that approximately 15,000 people have had the mutation and are in the process of undergoing treatment.
That means that some 6,000 Americans have been infected with the disease.
But why are so many people reluctant to get tested?
According to Dr. Gregory P. Tracinski, a professor of bioethics at Johns Hopkins University, the reason may be that the virus is difficult to test.
The researchers wrote in the journal Nature Genetics that “when individuals do not have the mutation for the disease, they are unlikely to have it” and that “those with the mutation are less likely to have tested positive” in comparison to people without the mutation.
It’s an issue that has also been raised in some other countries, with the Netherlands being the country that has seen the highest rate of cases and deaths from the virus, according to a study in The Lancet medical journal.
In the Netherlands, people who had the mutations in their DNA are now at a higher risk of contracting the disease from a new strain.
The researchers noted that the Dutch have also seen an uptick in cases and the death rate.
“The Dutch government has been slow to respond to the problem, but they have done some good things,” Tracinksi told The Associated Press.
The World Health Organization, however, has been less than impressed.
In a report last week, the organization said that “the number of cases, deaths, and new infections is at an all-time high, and this alarming increase is not being adequately addressed.”