This technology identified COVID-19 and is now helping doctors make life-or-death decisions. In late December 2019, a team of virologists from three major Chinese cities began analyzing swab samples collected from patients hospitalized with severe pneumonia. All these patients had previously visited the Huanan Seafood Wholesale Market in Wuhan. However, initial tests of the samples did not reveal any conclusive results. The genetic material found did not match any known pathogen. Later, doctors employed a new method called metagenomic testing, which helps detect all microorganisms in a sample, whether previously known or new.
This test showed the pathogen in the patients’ samples closely resembled coronaviruses, including those that cause severe pneumonia such as Middle East Respiratory Syndrome (MERS). “This was a game changer compared to previous pandemics,” said Associate Professor Niranjan Nagarajan from the National University of Singapore. After identifying the pathogen, tests to detect COVID-19 were developed, aiding efforts to control viral spread. This also accelerated treatment and vaccine development. To date, metagenomics’ most prominent application is this case. The method is now rapidly gaining popularity in hospitals, saving lives by enabling speedy diagnosis of sepsis and clarifying diseases of unclear origin.
When patients arrive at neurology wards with symptoms like seizures, fever, and headaches, doctors recognize the critical nature of the situation. These symptoms may indicate meningitis or encephalitis, serious conditions affecting the brain and spinal cord. However, doctors face a difficult dilemma: Is the disease caused by a virus or bacteria, or is it due to an overactive immune response in the brain? Limited testing facilities and time constraints often force doctors to administer broad treatments. “You must make immediate decisions,” said Charles Chiu, an infectious disease specialist and professor at the University of California, San Francisco. He is involved in new research related to metagenomic testing. “Currently, doctors treat critically ill patients for both infection and autoimmune diseases simultaneously.”
