What is HIV RT-PCR?
1. What is HIV RT-PCR? Booking HIV-RT-PCR
At present, the most popular detection method is the "Nucleic Acid Technology (NAT)" method, which is known as the RT-PCR method. RT-PCR is used to intercept HIV-1 virus RNA in plasma. To replicate viral proteins), direct detection of replicated HIV-I subtype virus signals in plasma rather than antibodies.
2. People's myths about the empty window period?
Within 7 days after exposure, it is called the empty window period, and RT-PCR can be measured 7-10 days after the contact. I want to know why I can test HIV for more than 7 days.
Our recommendation is to take the test 10 days later, because if there is no virus in the body, then the significance is the same after 10 days of contact. However, if the body has a virus infection, the amount of virus in 10 days and the amount of virus in 7 days will be quite different.
In the end, if it is an emergency, it must be contacted at least 7 days before the measurement can be made to avoid the virus being too small to be copied!
3. The accuracy of HIV RT-PCR and the diagnosis of AIDS?
"A lot of people will ask if RT-PCR is not allowed?" In fact, the sensitivity and specificity of HIV is one of the highest and most accurate methods for detecting HIV by RT-PCR. However, this type of detection requires very specialized operating techniques and environments to extract viral RNA. And for the sake of caution, it is more complete to add an enzyme immunoassay (ELISA) or PA-method or CLIA to perform an HIV antibody test. Of course, any kind of detection has false negatives and false positives for many reasons, such as: laboratory testing methods (using fully automatic equipment or manual operation), whether during the empty window, the subject's autoimmune situation, detection Personnel's familiarity with operational skills and so on will affect the test results. Therefore, if the subject is positive in the first test and cannot be said to be infected, it must be tested again by the second or third method, and finally confirmed by the *Western dot method* and according to the international Interpretation of standard interpretation, in line with positive criteria to confirm the infection with HIV, otherwise it can only be informed by unconfirmed or negative.
4. Is HIV antibody fast screening (Abbott in vitro diagnostic reagent) a government-approved test reagent that can be trusted?
Abbott = Alere (certified by the government for qualified testing reagents, and approved by the Ministry of Health and Welfare, as long as the qualified medical personnel and reagents are operated within the effective period
The results are all trustworthy. In addition, the Minsheng Medical Laboratory also accepts the quality supervision of HIV by government agencies and medical inspection associations. The test results are accurate, fast, and the quality is trustworthy.
5. Rapid screening definition
Definition 1: The shortest time from contact to inspection. For example: HIV RT-PCR.
Contact 7-10 days can be measured
Definition 2: HIV Abbot antibody rapid screening is based on the test reagent reaction time according to standard operating procedures and standard sample volume (blood + buffer)
Check the reaction time for 15 minutes
It is recommended to contact 7-12 weeks to test
Definition 3: HIV ELISA sandwich method Enzyme linked immunoassay Eliza fourth generation
It is recommended to contact 4-5 weeks to test
Conclusion: Fast screening can be defined as * the shortest time from exposure to inspection* and * the shortest time from blood collection to inspection report*
6. The Minsheng Medical Laboratory is the inspection and radiological operation organization approved by the Ministry of Health and Welfare.
HIV RT-PCR (HIV Reverse Transcription-PCR) analysis
1. Why do you need to use RT-PCR to measure HIV?
HIV (Human Immunodeficiency Virus)
>> belongs to RNA virus
The Nucleic Acid Technology (NAT) method is also known as the RT-PCR method. RT-PCR is the use of intercepting plasma HIV-1 viral RNA (for replication of viral proteins) to convert its RNA into One strand of cDNA, which is amplified by this cDNA, is a direct detection of replicated virus in plasma rather than antibodies.
RT-PCR> directly detects HIV-I viral RNA nucleic acid, can not detect HIV-II, can only detect abnormal signals
PCR >>Detect DNA, such as early hepatitis B virus detection
And HIV is an RNA virus, so HIV is measured by RT-PCR.
Detect problems that HIV RT-PCR may encounter:
2. Detect problems that HIV RT-PCR may encounter:
According to the medical literature, less than 1% of people, even if they are infected, will still be negative by RT-PCR for a long time. This group of people is called "immunity control". However, even if the amount of virus is not detected, the HIV antibody test of this group will still be positive, so why do I ask my patient to have a test for 3 months (HIV antibody fast screening), (HIV-ELISA), ( PA-method) or (CLIA) is relatively complete. Another reason is that antibodies can detect HIV-I and HIV-II. Although the probability of HIV-I is highest in the country, we must not only do RT- PCR misses any patients who are likely to be infected with HIV-II. In other words, no one would want to bear the risk of being infected. Some people have asked RT-PCR to check for normal HIV-RNA-free detection. At the 4th week, HIV antigen-antibody has been tested negative and normal. The antibody quick screening result is also normal, then is it possible for me to switch from a negative reaction to a positive reaction?
No virus in the body >> The virus can't replicate >> No antigen is produced >> No antibody appears >> How can there be a possibility of a positive reaction from a negative reaction?
Some patients have asked questions: Has the antibody been positively reacted after RT-PCR?
Minsheng Medical Laboratory: From the beginning of RT-PCR inspection in our unit, thousands of specimens have never encountered a case of positive reaction from negative reaction, and no other cases have been heard. It is also very bizarre and worth discussing.
Commonly known as the story of letting PCR kick the iron plate, let us continue to watch it.
Case study of false positive reaction: please refer to the case study of STD examination
Some people mention autoimmune controllers? The world's immune control controllers are all cases, and cases are usually magnified and discussed. There is no need to deliberately worry about whether we are the kind of people, especially the low-risk actors.
Be careful, this is a precaution against obsessive-compulsive disorder. If you have a cold, you should take a good look at the cold, rest more, don't stay up late, eat less irritating diet, and don't stay up late to watch a lot of useless articles and create your own panic.
Don't take AIDS preventive drugs, unless you are sure that the other person is infected.
Many infected friends shared their experiences with Minsheng Medical Laboratory. After personal experience, they said that the side effects are terrible. Nothing to eat, and the medicines for mental illness and depression are not eaten. If you are really scared, you are welcome to come to me. You also Can call me. If I am busy, the mobile phone can't be connected, you can also make an indoor call. If a phone call can help you solve your current doubts, I think this is also a medical examiner who can do my part for this society. Less than one person infected will consume less of a medical resource. I hope you will check out your doubts as soon as possible. Many units have free AIDS screenings, such as major hospitals and free screening stations in various regions, but they all have to make an appointment. If you don't want to wait too long, I want to know if I am infected with HIV or not. Screening, no appointment, no registration, 15 minutes to read the report. If you want to do a systemic sexually transmitted disease check and a respiratory virus related test, please call to make an appointment.
However, any method of detection has false negatives and false positives. For many reasons, for example: taking the wrong sample. Detecting the wrong blood. Sending the wrong report. There is no accurate notification of the empty window period. A large amount of caffeine < 5 cups of black coffee per day or more > Or eat food products containing pigments, ingest a large amount of papaya , carrots, laboratory testing herbs, test methods (using fully automatic equipment or manual operation), whether The period of the empty window, the subject's autoimmune or menopausal hormonal disorder <1 case>, the tester familiarity operation skills, etc. will affect the test results. Therefore, if the subject is positive in the first test and cannot be said to be infected, it must be tested again by the second or third method, and finally confirmed by the Western Dot Method* and interpreted internationally. Standard interpretation, in line with positive criteria to confirm the infection with HIV, otherwise it can only be informed by unconfirmed or negative.
I have heard that in general, even teaching hospitals require patients to be exposed to at least 14 days (2 weeks).
Why does the HIV RT-PCR at Minsheng Medical Laboratory be detectable 7-10 days after exposure? The reason is that laboratory personnel operate key technologies for virus concentration.
Why do the reports take 4-5 working days to come out? Can't you hurry up? When will the report come out the fastest?
If the report comes out early, we should worry about whether the number of viruses responds. We should inform the subject to arrange for another review. If the results are normal and no detectable HIV RNA is detected in the blood, we will be in the 4th or the 5 working days to issue an export report, the time of the report will be based on the work schedule of our medical laboratory.
So don't worry too much about why the report takes so long.
Why do some units even have hospital expenses of 4,800-6,000 yuan? The original HIV RT-PCR test was conducted to track the amount of virus in the body and to monitor the virus after cocktail therapy in patients who have been infected with HIV. Now, the situation has changed, and if there is any sexual contact, they will worry about whether they will get HIV.
In general, what we often hear is that if the condom is broken, what is the probability of infection? What is the probability of oral sexual intercourse being infected?
In fact, all of the above are low-risk, the infection rate is extremely low, but everyone does not want to bear the risk of infection, and Minsheng Medical Laboratory is committed to preventing AIDS and other sexually transmitted diseases, so the cost is set to be more affordable and professional. It is recommended to inform other risks of possible infection. The reason why the general hospital is unwilling to accept the people's self-funded examination is that "the doctor thinks it is unnecessary", and the doctor can guarantee that you have no other source of infection without symptoms?
To do the test is to provide evidence that you are not infected, can not be empirically determined that there is no other source of infection without testing and too much drug abuse caused a lot of drug resistance to make the treatment effect of the patient greatly reduced. Minsheng Medical Laboratory has encountered too many examples that can't be checked in the hospital.
HIV empty window myth?
After 7-10 days of exposure, the amount of virus will peak on the 10th day, so this is the best time to use HIV RT-PCR to detect HIV RNA virus.
Our recommendation is to take 7-10 days from the start of the contact and then measure it, because if there is no virus in the body, then the meaning is the same after 10 days of contact, but if the body is infected with the virus, the amount of virus for 10 days. There will also be considerable differences with the amount of virus in 7 days.
If it is in an emergency (needle, unintentional sexual intercourse, rape, etc.), it must be contacted for at least 5 days before the measurement can be made to avoid the virus being too small to be copied!
Important: According to the definition of the World Health Organization for 12 weeks, an antibody screening test is required to exclude HIV infection. As long as patients who perform RT-PCR and early syphilis FTA ABS testing at Minsheng Medical Laboratory, we will provide 3 months from the start of contact. AIDS antibody tracking review and syphilis review for 1 month . AIDS review and AIDS false positive reaction research - sponsorship
Nucleic acid drug controller (B liver, C liver drug treatment patients, special drug treatment patients)
Need to stop the drug for 3 months before HIV RT-PCR and perform antibody screening after 3 months
The environment does not spread HIV, the hand does not spread HIV, and the diet does not transmit HIV. None of the above is a route of transmission.
No matter what blood fluid or dirty things your hand touches, or someone else helps you masturbate, hand over, you help others masturbate, hand over, water splashed on the road, touch the doorknob in the hospital, feel acupuncture on the road By the way, how can you be afraid to think that there is a source of HIV infection, it is impossible to be infected with HIV, and there has never been such an infection. Such infections such as "environment", "hand", and "finger" are impossible.
The symptoms that appear on the first day to the seventh day after infection cannot be caused by HIV. If you have symptoms on the 7th day, you should seek medical advice to check the cause, instead of pre-emptively thinking that you have won the prize, because most of the symptoms at this time are oolong. "Is my symptoms caused by HIV?"
Acute infections in people with symptoms, most (96%) have a fever (body temperature over 38 degrees). No matter how many physical symptoms you have, if you don't have a fever, the chances of getting HIV are very low. There are unsafe sex behaviors, it is necessary to do HIV screening after 12 weeks, but it is not necessary to always take a magnifying glass to see the slight changes in your body. If there is no fever, the bitter worry is superfluous to me. If you have a fever, it does not mean that you are infected. It may be flu or other viral bacteria. It is most important to see a doctor first and find out the cause.
Will the XX medication I take or the XX behavior I take affect HIV testing?
The answer is very simple. Only taking HIV treatment drugs, B-hepatitis treatment drugs (liver Anergy and Phillips), and anti-immunity rejection agents after organ transplantation may affect HIV testing. Otherwise, regardless of whether you take medicines for cardiopulmonary, kidney, kidney, brain and intestines (including cold medicine, Baogan pills, steroids, Chinese medicine), or smoking, drinking, playing cards, staying up late, or consciously weak and weak immunity,
All have no effect on HIV testing. The HIV test here includes antibodies (ELISA, PA, Western blot), fast screening, RT-PCR.
I tested the RT-PCR negative reaction (or antibody negative) after X weeks. Can I still have HIV?
According to the consensus of the global public health community, it is recommended to "negative reactions in antibody tests for 12 weeks" to exclude HIV infection. The tests here include ELISA, PA, and blood fast screening.
The closer to the 12-week screening result is a negative reaction, the chance of turning into a positive reaction is small. Standing on cost-effective considerations, it is the most economical way to do antibody testing for 12 weeks. If you are worried about overdoing and being overwhelmed, you may be able to do an HIV test (PCR, antibody) in advance to help detect early infection (if positive) or temporary relief (if negative), but the moderator recommends 12 weeks or more. To do an antibody test, make sure it is done once and for all.
Note: Sexual behavior with HIV-infected persons, the risk of HIV infection per sexual contact: the risk of infection with an acquired type of anal sex (ie No. 0) is estimated to be 1-30% each time; the insertion type has no anal sexual intercourse (ie number 1)
The risk of infection is similar to that of the recipient type of vaginal intercourse (ie, the woman), which is estimated to be 0.1-10% each time; the risk of infection of the inserted type of vaginal intercourse (ie, the man) is estimated to be 0.1-1% each time. Only the above-mentioned unsexual anal sex or no vaginal sexual intercourse is a high-risk sexual behavior. Oral sex is considered to be a much less risky exposure than the above sexual contact, but no good risk estimates can be provided, but there are cases of HIV infection reported by oral sex, high HIV virus, periodontal disease, Oral ulcers, oral contact with semen or prostatic fluid are risk factors for oral sex infection.