Researchers at Washington University School of Medicine have developed a new test that detects virtually any virus that infects people and animals, thereby advancing early detection of future outbreaks of deadly viruses such as Ebola, Marburg and severe acute respiratory syndrome (SARS).
Many thousands of viruses are known to cause illness in people and animals, and making a diagnosis can be an exhaustive exercise, at times requiring a battery of different tests.
That is because current tests are not sensitive enough to detect low levels of viral bugs or are limited to detecting only those viruses suspected of being responsible for a patient's illness.
"With this test, you do not have to know what you are looking for," said the study's senior author Gregory Storch, professor at Washington University School of Medicine in St. Louis.
"It casts a broad net and can efficiently detect viruses that are present at very low levels. We think the test will be especially useful in situations where a diagnosis remains elusive after standard testing or in situations in which the cause of a disease outbreak is unknown," Storch noted.
The new test - called ViroCap - can detect viruses not found by standard testing based on genome sequencing, the findings showed.
The researchers evaluated the new test in two sets of biological samples - for example, from blood, stool and nasal secretions - from patients at St. Louis Children's Hospital.
In the first, standard testing that relied on genome sequencing had detected viruses in 10 of 14 patients.
But the new test found viruses in the four children that earlier testing had missed.
In a second group of children with unexplained fevers, standard testing had detected 11 viruses in the eight children evaluated.
But the new test found another seven, including a respiratory virus called human adenovirus B type 3A, which usually is harmless but can cause severe infections in some patients.
In all, the number of viruses detected in the two patient groups jumped to 32 from 21, a 52 percent increase.
The study was published online in the journal Genome Research