As of December, the prevention and control
of the new crown pneumonia epidemic in China has entered a stage of
normalization. In the first half of 2020, the overall IVD industry has
conducted full market competition around the market opportunities brought by
the new crown epidemic. Many companies have seized this opportunity, which
greatly improved their market value and brand influence in the first half of
this year. Entering the second half of the year, the global epidemic is still
not over. We still have to "not be paralyzed, not war-weary, and not let
down." In the context of the global pandemic of the new crown epidemic, we
must remain vigilant and awe.
Today, Hubei Jinjian Biology Co., Ltd will briefly analyze and interpret immunodiagnosis and nucleic acid diagnosis.
Immune testing is based on the principle of specific reaction between antibody and antigen. It is widely used in major infectious diseases such as HIV, hepatitis B, and hepatitis C by detecting viral proteins (antigens) in the body or antibodies specific to viral proteins in the body. Detection.
There are generally two ways to detect viral proteins: one is to use antibodies to detect antigens, which is to find direct evidence, and the detection of antigens must be infected; the other is to use antigens (usually recombinant) to detect antibodies, which is Indirect evidence that people have this antibody, and not obtained through vaccines, indirectly proves that they have been infected with this pathogen. Antibodies are the products of humoral immune response after the body is infected with the virus.
However, it is worth mentioning that the detection and nucleic acid detection are not in conflict, nor can they replace each other. They are both important means for the diagnosis of virus infection.
A positive specific antibody test cannot be used as a "gold standard" for viral infection like a positive viral nucleic acid test. Early patients have low antibody concentrations and have not even produced an immune response, which is limited by the detection window. At the same time, because antibody detection is susceptible to the presence of some interfering substances in blood samples (such as rheumatoid factor, non-specific IgM, high concentration of hemoglobin caused by hemolysis, etc.), "false positive" results appear, so antibody detection must use IgM and IgG is tested at the same time and usually requires multiple dynamic tests to confirm.
The difficulty in the development of viral
protein-based immunological detection programs lies in the production of
antibody raw materials. Compared with nucleic acid detection kits,
immunological detection kits require longer development time and higher
In terms of applicable scenarios, antibody detection is fast and easy to operate, which is of great significance for rapid detection and investigation of suspected patients. It is more suitable for screening of fever population in primary medical institutions, communities and township health centers, and is of great significance to effectively control the large-scale spread of COVID-19.
Compared with nucleic acid diagnosis,
immunodiagnostic kits can also quickly screen for asymptomatic virus carriers,
and can be used for distributed screening in high-traffic public places such as
airports, stations, and docks, providing comprehensive prevention and control
of the epidemic and thorough investigation provide technical support.
Every crisis is a challenge as well as an opportunity for growth. I hope that all countries in the world can get the victory of the Novel coronavirus vaccine as soon as possible.