POST-VACCINE TEST AND SALIVA TEST, the new kits available for COVID-19 detection
All countries are under tremendous pressure in detecting, preventing, or treating 2019-nCoV.
To deal with the epidemic situation, the only lasting solution seems to be the administration of a safe and effective vaccine.
Likewise, for those who have not yet had the opportunity to be vaccinated, it is important to be able to detect a possible COVID-19 infection in time.
In the previous post we explained the differences between antigen kits and antibody kits.
In this post we are going to focus on two new kits that have come on the market and that we have available in Salengei: Post-Vaccine Antibody Kit and the Saliva Antigen Kit.
Post-Vaccine Test – Neutralizing Antibody Test
First of all, we will ask ourselves, what is the Neutralizing antibody test?
In the process of vaccine development and commercialization, the most important index to evaluate the effectiveness of the 2019-nCoV vaccine is the neutralizing antibody content in the subjects.
Therefore, the detection of neutralizing antibodies (NAbs) 2019-nCoV is the priority among the priorities to accelerate the fight against the global epidemic.
I have been vaccinated and I want to know if I am immunized
The 2019-nCov Neutralization Antibody Detection Kit specifically detects binding antibodies.
Binding antibodies bind to a pathogen, such as a virus, mimicking the interaction between the pathogen and the cell, interfering with its ability to infect.
In order for the virus to enter the cell, the receptor-binding domain (RBD) of the “S” protein (spike) in the virus needs to interact with ACE2 receptors in the human cell.
The 2019-nCoV Neutralizing Ac Test’s S Protein (RBD) neutralizing antibody can prevent the S protein (RBD) from binding to the ACE2 receptor, thereby blocking the virus’s contact with the host cell and ultimately preventing infection of the virus.
Antibodies present in serum or plasma that can prevent this binding thus preventing the virus from entering the cell and are known as neutralizing antibodies.
By attaching to interacting proteins rather than the live virus or live cells, this reaction can be reproduced and therefore these neutralizing antibodies can be detected in a very efficient and rapid manner, compared to COVID-19 antibody assays from the start of the pandemic.
How is it done?
It is a rapid immunochromatographic assay for the semi-quantitative detection of COVID-19 neutralizing antibodies from a drop of finger blood.
It is recommended to perform this test only on individuals with the vaccination process already completed and after the days of margin in which the brand of the vaccine is assured, the antibodies in question must have developed.
The test result is evaluated by comparing the color band of the cassette with the color card included in the kit instructions to have an estimate of the concentration of antibodies generated and the efficacy of the vaccine.
The result is obtained in 15 minutes.
Advantages
To know if we have antibodies after the vaccine.
- Depending on the thickness of the stripe, it gives you a qualitative idea of the level of immunization.
- Easy to make.
- Try it at a relatively low cost.
- No appliances required
- It is performed with a capillary blood sample
- Maximum time 15 minutes.
Limitations
- It is only valid for people with the vaccination process already completed.
Difference with the antibody test
This test is different from the antibody test that we have been learning about so far.
In UNVACCINATED patients who have passed the infection, we would perform this type of test.
The result would indicate whether they have been immunized after the infection.
The antibody test is a rapid immunochromatographic test for the qualitative detection of IgM/IgG antibodies to coronavirus type 2.
The serological test, which is performed from a drop of blood obtained by a finger prick, is recommended in the following cases:
- Once the quarantine time of a positive case has elapsed.
- To find out if infection occurred in the past at any time.
IgG levels could indicate immunization.
Positive IgM levels would indicate that it is
Saliva antigen test
It is a rapid immunochromatographic test for the qualitative detection of the antigen of the nucleocapsid protein of the coronavirus type 2.
When we want to know if we’re positive, and we want a quick result
They are used as routine screening or on the third day of contact with a positive SARS-CoV-2 or suspected case if no symptoms have appeared before.
The test can be performed just as safely in two different ways, the most common or nasopharyngeal with the help of a nasal swab.
But while it is true that there is now a new version, through saliva.
This test is a less invasive form from the Nasopharyngeal onwards.
This rapid antigen diagnostic test detects the molecular fragments of the membrane proteins of the SARS-CoV-2 virus.
As in the case of nasopharyngeal antibodies, it allows us to know if the person is a carrier of the virus.
This test is very effective because the result is obtained in 15 minutes.
If the antigen result is positive, it must be confirmed with a PCR.
Advantages
- Less invasive than the nasopharyngeal antigen test.
Avoid the discomfort of the swab in the nose - Easy to perform.
It only requires a saliva sample. - Try it at a relatively low cost.
- Comfortable for children
- Minimizes sampling errors
- Maximum time 15 minutes.
Limitations
- Follow the recommendations on how to test.
Recommendations on how to perform the test
- Before collecting oral fluid, instruct patients not to place anything in their mouths, including food, beverages, gum, or tobacco products, for at least 10 minutes prior to collection.
- Instruct patients to cough deeply 3 to 5 times to release sputum from the deep throat into the mouth.
- It is recommended to collect the first sputum after a deep cough in the morning.
If you have any questions or clarifications about any of these concepts, you can contact our technical department, which will answer your questions.
