1. How to identify confirmed cases?

Suspect cases with one of the following etiological or serological evidences:

a. Real-time fluorescent RT-PCR indicates positive for new coronavirus nucleic acid;

b. Viral gene sequence is highly homologous to know new coronavirus

c. NCP virus specific IgM and IgG are detectable in serum; NCP virus specific IgG is

detectable or reaches a titration of at least 4-fold increase during convalescence compared with the acute phase.

2. What does it mean if I have a positive test result?

If you have a positive test result, it is very likely that you have virus. Therefore, it is also likely that you may be placed in isolation to avoid spreading the virus to others. However, due to unknown source interference substances, the test result may still be positive which is called false-positive. Your healthcare provider will work with you to determine how best to care for you based on the test results along with other factors of your medical history, and your symptoms, possible exposures, and geographic location of places you have recently traveled.

3. What does it mean if I have a negative test result?

A negative test result means that the antibody that caused by virus was not found in your sample. For virus, a negative test result for a sample collected while a person has symptoms usually means that virus did not cause your recent illness.

However, it is possible for this test to give a negative result that is incorrect (false negative) in some people with virus. This means that you could possibly still have virus even though the test is negative. If this is the case, your healthcare provider will consider the test result together with all other aspects of your medical history (such as symptoms, possible exposures, and geographical location of places you have recently traveled) in deciding how to care for you. It is important that you work with your healthcare provider to help you understand the next steps you should take.

4. Why should I use this product?

Currently, the most commonly used diagnostic method is nucleic acid testing, but this technique has been proved unable to detect all virus carriers, especially when testing commonly used upper respiratory tract samples. For confirmed cases, sometimes multiple testing and tests with multiple samples are needed to obtain positive results. And there is situation that a high degree of suspected patients cannot obtain positive results with nucleic acid testing. There are four potential reasons:

1) the viral loads in upper respiratory tract samples are much lower than that in lower respiratory tract samples in virus patients

2) the releasing viral loads of patients in different stage of infection varies with a wide range;

3) the collection of high-quality swab specimen requires skillful health-workers;

4) PCR reagents from different sources have high variance.

The above issues pose serious challenges to the provision of timely life-support treatment and preventive isolation. Therefore, serological detection is very necessary.

The specific clinical significance and value of serological detection for virus area follows:

1) for the suspected case of the first doctors' office visiting and the confirmed case with the clinical diagnosis but without viral nucleic acid testing, the positive results of antibody can be used as an aid in the diagnosis of virus;

2) for the healthy close contacts with antibody positive result, they should be regarded as possible carriers, extend the isolation observation period, improve the nucleic acid testing frequency, increase sample types for nucleic acid testing, and carry out the close contact investigation;

3) patients tested by viral nucleic acid, serum antibody positive result indicates that specific immune response has been induced in body, which can help doctors to judge the connection between the body's immunity and the subsequent development of the patient's disease;

4) used for quantitative assessment of serum antibody levels in convalescent patients, among which high titer antibody plasma can be used for the treatment of severe patients;

5) combine with viral nucleic acid testing to identify potential virus carriers in key populations, such as travelers in outbreak countries or regions, participants in important meetings or events, and people returning to work or school. Isolate and monitoring the people with virus nucleic acid negative but antibody positive, in order to detect potential virus infection in time, reduce the transmission risk.