The U.S. government is now working to control and slow the spread of new coronaviruses, and testing is the focus of work. Molecular biologists and virus researchers Maureen Ferran are working on how these diagnostic reagents work and whether adequate tests are currently available. A series of basic questions were answered.
Who will be tested for the new coronavirus?
At present, there are two main reasons why people are being tested for coronavirus: first, symptoms; and second, contact with infected people. The main symptoms of the new coronavirus SARS-CoV-2 infection are fever, dry cough, and shortness of breath. These symptoms look very much like the symptoms of flu and the common cold, so clinicians must also confirm whether the patient needs to be tested for the virus; initially The United States CDC recommends testing only those who are symptomatic and likely to be exposed to the virus, but to the surprise of public health officials, patients who tested positive for the first time did not have a clear history of exposure, a development that suggests the virus may be Transmission in the area means that it can be easily transmitted from person to person or that people do not show severe symptoms when the virus is transmitted.
In response, the United States CDC changed its previous proposal on March 4 to allow anyone with a similar COVID-19 to be tested (provided the clinician agrees). Because the number of available tests is very limited, the CDC encourages clinicians Minimize unnecessary testing and consider patient exposure risks before testing. Testing may be done to isolate infected people and slow the spread of the virus. Another benefit of testing is that it allows public health workers to more accurately understand the number of cases and the spread of the virus among the population.
What does it feel like to be tested?
For patients, the process of detecting the virus is simple and can be performed almost anywhere. Usually a cotton swab is taken from the patient's nasal cavity to collect cells at the back of the nose. The sample is then sent to the laboratory for testing To determine whether the patient's body is infected with the virus, the same sampling process is also used to collect samples from patients who have been tested for influenza.
How is it detected?
Collecting a sample is very simple, but determining whether an individual is infected with the new coronavirus is relatively complicated. The current detection method is to find the genetic material (RNA) of the virus from the patient's cells. In order to detect the presence of viral RNA from a patient's sample, the laboratory needs to perform reverse transcription polymerase chain reaction. This method first reverse-transcribes the viral RNA into DNA and then replicates the DNA until sufficient After copying, the researchers used a quantitative PCR instrument to detect the sufficient amount of DNA produced.
If genetic material derived from the virus is detected in a patient's sample, the patient will then be diagnosed with a new coronavirus infection; obtaining test results usually takes 24-72 hours. In the early stages, people pay great attention to the accuracy of the test results. Genetic testing is usually more accurate than rapid influenza test results, and the benefits of this test outweigh the risk of error.
