What is the process needed to do a virus nucleic acid test? How much will it cost?

When it comes to the cost of nucleic acid testing, there should be many people concerned. Especially some time ago, there was a news report that the United States had to pay $65,438+$0,600 for COVID-19 nucleic acid testing. Seeing this news, many friends are undoubtedly shocked. Is nucleic acid testing really that expensive? So how much does it cost to do a COVID-19 nucleic acid test in China? Let's talk about the problem of nucleic acid detection together.

1. How much does it cost to do a nucleic acid test in China?

In fact, we have issued a corresponding notice on the cost of nucleic acid testing. It can be roughly divided into two situations:

● 1. The cost of nucleic acid testing for confirmed cases and suspected cases, like the cost of treatment, is completely borne by the state, and individuals pay nothing.

As for the cost of nucleic acid testing in COVID-19, in fact, the state has already issued relevant notices. On June 22nd, 2008, the Ministry of Finance and the Joint Medical Insurance Bureau issued the Emergency Notice on Doing a Good Job in Medical Security for Pneumonia Infection in novel coronavirus. The notice clearly pointed out that all the expenses for the treatment of suspected patients and confirmed patients except medical insurance reimbursement are borne by the government, and patients can receive treatment with confidence.

To put it simply: apart from medical insurance reimbursement, the expenses incurred by suspected patients and confirmed patients in the course of treatment are partially subsidized by the individual, and the individual does not bear any expenses. Among them, nucleic acid detection is naturally included.

Then someone asked, I am neither a suspected patient nor a confirmed patient, but I have a fever or my unit needs to do viral nucleic acid testing when it returns to work. So how is the fee calculated? Is it free? In fact, some provinces and regions have issued relevant notices on this issue. Let's take another look.

2. Nucleic acid detection in fever clinic costs vary from place to place. Let's look at the testing costs in Hunan and Guangdong.

Cost of nucleic acid detection in Hunan Province

There are differences in nucleic acid testing fees between public medical institutions and third-party testing institutions in Hunan. According to the Notice on the Temporary Establishment of COVID-19 Nucleic Acid Testing Price Project:

★ Public medical institutions: The public medical institutions affiliated to the designated nucleic acid detection station in COVID-19, this province temporarily set up the "COVID-19 nucleic acid detection" medical service price item, and the charging standard is tentatively set at 40 yuan/person, excluding the nucleic acid detection reagent fee. The expenses incurred are reimbursed by medical insurance, and patients are "zero compensation".

★ Third-party testing institutions: The third-party testing institutions in COVID-19 in the province should carry out COVID-19 nucleic acid testing at no more than 160 yuan/person (including all expenses such as reagents and consumables), and encourage further reduction of the testing price.

Judging from the price standard of nucleic acid testing in COVID-19, Hunan Province, if it is tested in a public medical institution, although it costs 40 yuan/person-time, it can still be reimbursed by medical insurance in the end, realizing personal free. And if it's a third-party test, then the highest charging standard is not higher than 160 yuan/person.

Cost of nucleic acid detection in Guangdong Province

The cost of nucleic acid testing in COVID-19 is much better than that in Hunan. On February 28th, the Information Office of Guangdong Provincial Government held the 34th press conference on epidemic prevention and control. In Guangdong, nucleic acid detection and lung CT examination of newly diagnosed pneumonia patients in fever clinics were included in the scope of special medical security, realizing zero charge for nucleic acid detection and CT screening in COVID-19. Even in third-party testing, such as Guangzhou Jinyu Medical Testing Center, Guangzhou Daan Clinical Testing Center, Guangzhou Huayin Medical Testing Center, etc. The cost of testing does not need to be borne by patients, and it is all borne by the government.

In Shenzhen, Guangdong Province, according to the implementation standards of Guangdong Province, Shenzhen issued the Notice on Strengthening the Medical Security of COVID-19 Epidemic, in which Article 3 pointed out that during the epidemic period, all outpatient screening expenses (including but not limited to chest CT and nucleic acid detection) of COVID-19 screening subjects in fever clinics were temporarily included in the scope of medical insurance funds. In addition, for some people who are isolated at home in Shenzhen, the detection of viral nucleic acid is also free.

That is to say, in Guangdong, as long as you are the screening target in COVID-19 during the epidemic, there is no charge for COVID-19 nucleic acid test and chest ct screening in fever clinic.

Secondly, the cost of nucleic acid testing in COVID-19 was mentioned above. Let's talk about what processes are needed for nucleic acid testing.

This kind of nucleic acid detection is usually carried out in the molecular biology genetics room of the laboratory, and as a member of the laboratory, I am most familiar with nucleic acid detection. In addition to the previous sampling is not in the laboratory, other virus inactivation, nucleic acid extraction, gene amplification and so on are carried out in the laboratory. Let's briefly introduce these processes, and I will try my best to make them easy to understand and make them easier for everyone to understand.

● Step 1: Swallow swab sampling.

The first step of this COVID-19 nucleic acid test is to take throat swab samples from patients. This is mainly done by the staff of CDC or the staff of fever clinic. The patient only needs to take off the mask, then open his mouth and make an "ah" sound, so that the whole area is exposed along the back wall. After that, the sampler will extend the sampling stick to the patient's posterior pharyngeal wall for smear and sampling, and finally put the sample into the reagent tube for sealing, thus completing the sampling.

When sampling, the patient will feel vomiting. After all, sampling is always in the posterior pharyngeal wall, which will produce certain stimulation. And you will feel a little foreign body sensation after taking it for a while. After all, the sampling pump rubs back and forth around the posterior pharyngeal wall, but these are normal.

Sampling is actually very important, which is related to the accuracy of the test results. If the sampling is unqualified and the virus is not smeared, it will affect the test results. In addition, sampling is also dangerous. After all, when sampling, we are facing patients. If the patient is diagnosed, it is to face the virus directly. Therefore, the sampling personnel are fully armed and must be wrapped up from head to toe, that is, do a good job of protection.

After the sampling is completed, the newly collected throat swab samples will be handed over to the inspectors in the inspection room through the special channel for sample handover.

● Step 2: Inactivate the virus.

(Inactivated in a water bath at 56℃ for 30 minutes)

When the collected throat swab samples are sent to the laboratory, the laboratory staff will inactivate the samples.

Why inactivate the virus? Because this is the first step of nucleic acid extraction. We put the sample in a water bath box and sterilize it at 56 degrees for 30 minutes.

Why do you have to go through 56 degrees and 30 minutes of anti-virus operation? This is because the virus can be inactivated after being treated in a 56-degree water bath for 30 minutes, which can not only ensure the safety of testers, but also not affect the test results, so that the risk of infection of operators will be greatly reduced.

In addition, after the sample is inactivated for 30 minutes, it needs to stand at room temperature for 20 minutes, which can prevent aerosol pollution caused by high temperature opening.

Step 3: nucleic acid extraction

After the virus is inactivated, the step of extracting nucleic acid is very dangerous and must be carried out in the biosafety cabinet, because this is the place closest to the virus and the place with the greatest risk of infection. When opening the cover of the sample in the safety cabinet to extract nucleic acid, it is necessary to open the cover very carefully, because if you are not careful, aerosol may be formed, which will not only pollute the safety cabinet, but also cross-infect other samples and form a "false positive".

The so-called nucleic acid extraction is to extract viral RNA from samples, that is, nucleic acid. However, due to the unstable structure of RNA, it needs to be transformed into DNA first. This process involves PCR reaction, that is, through denaturation, annealing, extension and other steps, through the process of reverse transcription, the two strands of RNA are separated, so that the virus information is transmitted to the single strand of DNA, thus extracting the virus nucleic acid.

● Step 4: Gene amplification

After the nucleic acid is extracted, the amount is too small for the machine to detect at all. At this time, it is necessary to use the extracted viral nucleic acid as a template to make DNA replicate itself continuously. After 20 ~ 30 replications, the content of template DNA can be amplified to more than 6.5438 0 million times. In this way, after amplification, if new coronavirus nucleic acid exists, it can be detected. Just like when we check whether there is bacterial infection in the microbiology room, we need to cultivate bacteria before we can carry out identification and drug sensitivity test. It is a truth that the quantity should be large enough to be detected.

Generally speaking, the core of total nucleic acid detection is to make DNA constantly replicate itself, accumulate fluorescence signals, and finally be detected by instruments and then interpreted.

Ideally, if there is COVID-19 in the patient sample, an S-shaped curve will be formed between the number of cycles and the amount of fluorescence, and it can be judged that the nucleic acid test is positive. If there is no or a small amount of COVID-19, there is no similar curve, and it can be judged that the nucleic acid test is negative.

In short, the whole process of nucleic acid detection in the laboratory, from sample inactivation, nucleic acid extraction, gene amplification, result analysis to final report, will last about 6 hours. If the test result is "positive", it needs to be checked again. Therefore, it takes at least 12 hours to release the COVID-19 nucleic acid positive report.

Third, the following questions:

The above is the explanation about the cost of nucleic acid testing and the procedures that nucleic acid testing has to go through. Through my above explanation, I believe everyone has a general understanding. I hope my answer will satisfy everyone.