Q & A on nucleic acid testing


Multiple rounds of nucleic acid testing have been carried out in the city recently. Why are they necessary? What should we pay attention to while taking the test? Experts from Wuhan Center for Disease Control & Prevention gave their explanations.

  1. Why nucleic acid testing must be done as early as possible?

1. The Omicron variant is to blame for the newest wave of pandemic. It spreads faster than earlier variants of the COVID-19 virus.

2. The stealthy Omicron strain is difficult to detect and people infected with the virus are usually not obviously symptomatic. The virus can cause a surge of infections.

3. Only by responding fast and firmly, carrying out nucleic acid testing to filter out COVID-positive cases as quickly as possible, and taking resolute measures to control the epidemic, can we curb the extension of the transmission chain and prevent the virus from infecting more people.

Experts: Timely nucleic acid testing is the most effective way to find out the Omicron variant.

  1. Why are multiple rounds of nucleic acid testing needed?

1. Nucleic acid testing involves multiple steps including sample collection, storage, transportation, and nucleic acid extraction and amplification. Any improper handling might lead to a "false negative” result.  

2. In the Omicron variant’s incubation period, the amount of virus in the human body has not yet reached a detectable level. Testing during this stage can easily produce "false negative" results. 

3. Transmission of the Omicron variant often occurs between 1.5 and 5 days following infection. Transmission from one person to another takes an average of three days. Only through dynamic and repeated nucleic aid testing in a short period, can we effectively screen out positive cases.  

Experts:  People vary in physical conditions and tolerance for viruses, and these individual differences will impact sampling results. Therefore, how many rounds of nucleic acid testing are needed should be decided based on a comprehensive consideration of various factors.

  1. What should we pay attention to about nucleic acid testing?

1. If you have just been vaccinated, you should not take the test until 48 hours later.

2. Wear a mask properly throughout the process, take care of personal protection, and maintain social distance.  

3. Wait for your turn patiently to get tested. Only after the nurse finishes sanitizing their hands and take out new swabs, can you go forward and quickly take off your mask for the testing.

4. Open your mouth for the testing and do not make the sound "Ah” to make sure no virus-laden aerosols enter the respiratory tract.

5. Keep away from items on the testing desk. Do not put your personal items such as mobile phones, ID cards, or keys on the desk.

6. Put on your mask and leave the testing site immediately after the testing is done.

Experts: While doing nucleic acid testing, you simply need to pull down your mask and open wide your mouth.