Questions and Answers | What was first “Yang” has become “Yin”! Will there be re-infection within the family? What’s up with “nucleic acid positive, antigen negative”?Flying into the homes of ordinary people
“The first batch of colleagues who passed positive have become negative and positive again. Is it a re-positive or secondary infection?” “Will the positive infections in the family cause re-infection on the joint? “Am I yin or yang?”, the discussion about “yin and yang” has become a hot topic in Seconds, which often confuses people…
Dr. Ai Jingwen, Department of Infectious Diseases, Huashan Hospital Affiliated to Fudan University, told reporters that first of all, we must understand that Fuyang and reinfection are two different concepts. The first means that the infected person gets two positive results in the same infection cycle. In general, when the second positive result is found, it is no longer contagious; while the latter means that the infected person has experienced two different infection cycles, and the time of the second infection Spans are often long, which is contagious.
Some netizens had one bar on the antigen after infection, but two bars were found after a few days Is this the second infection or Fuyang?
Ai Jingwen said that the first possibility is that the sampling in the previous test was not in place, so the previous test showed a false negative; the second possibility is that the residual pieces of the virus in the body are excreted from the body one after another, so the antigen will be positive again. . However, according to past experience, most of these Fuyang people were found because some residual pieces of the virus were found, and generally there will be no re-infection to others. Of course, there is a third possibility, that the patient is indeed positive for the virus again in a short period of time, but this type of situation often occurs in patients with obvious immunodeficiency such as tumors, and rarely occurs in people with good general health.
The virus spreads very quickly in the same family, especially in a family with a large population Will there be repeated infection after one round of infection?
Ai Jingwen pointed out that people with a positive infection generally will not be re-infected in a short period of time after the antigen turns negative. If the roommates are infected within 1 to 2 weeks, there will be essentially no cross-infection or repeated infection during the recovery period. However, if you encounter a high-risk infection environment again one month after turning negative, the chance of re-infection will gradually increase, but in general, the chance of infection will increase significantly after 6 months or more. For young and middle-aged adults, the symptoms of a secondary infection are often milder than the first; but for the elderly with fragile immune systems, secondary or multiple infections require more careful health monitoring and timely symptomatic treatment to further reduce the risk of progression. to serious illness.
“Nucleic acid positive, antigen negative”, many friends have encountered this kind of trouble, what’s going on?
There are many reasons for this contradictory result. Ai Jingwen said that it is generally believed that the sensitivity of antigen detection is relatively low, and it can only be successfully detected when the virus content in the body is relatively high, so antigen detection may not be able to detect positive early. stage of infection and late recovery. That is why some patients are antigen-negative on the first day of fever, but are antigen-positive on the second day. In addition, since everyone can perform antigen detection, the accuracy of the test results is also related to whether the sampling standards are in place and whether the operation is standardized. Of course, false positives can also occur in nucleic acid tests, which are also related to whether the reagents are contaminated.
At this time, when more and more people around are infected, instead of obsessively following the test results and explaining “yes or no”, it is better to pay attention to your own symptoms. When you have been in contact with a positive infection, or even with symptoms of fever, cough and sore throat, it makes sense to carry out antigen tests at this time. If you have symptoms, and the antigen test is again positive, it is very likely that you are infected; if you have related symptoms, but the antigen test is negative, if it’s not necessary, you don’t need to go at all. across the street to find a nucleic acid point for a nucleic acid test to prove you are “positive.” You just need to treat the symptoms according to your own situation, and then do antigen or nucleic acid tests according to the needs after the symptoms disappear.
In addition, since the new crown is a self-limiting disease, mild and asymptomatic patients do not need to take antiviral drugs. Of course, because the new coronavirus is highly contagious, if you have a fever and suspect that you are infected, then even if you cannot be sure for now, you should also pay attention to isolation as much as possible, especially if there is. are elderly people at home. In any case, protecting the elderly will be the main priority when dealing with the peak of the first wave of the epidemic. (Xinmin Evening News reporter Zuo Yan)
Editor: Wei Jiawei
