P24 Antigen

P24 is a capsid structural protein that makes a protein shell on the surface of the HIV (human immunodeficiency virus). It helps in identifying the actual HIV particles present in the blood. They show a positive result when the test is taken after two to three weeks of HIV infection. P24 protein cannot be detected after a week of HIV infection as the virus takes some time to get multiplied. It is again undetectable when sufficient antibodies to HIV are produced. At this point, the standard HIV antibody test shows a positive result. Later in the course of HIV, it becomes detectable.

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Does the p24 antigen get detected after nine months of HIV infection without treatment?

Query: Hello doctor,I am concerned regarding p24 antigen detection. I read in different articles that it is delectable for only two months, and later it disappears as antibodies are formed. The antigen appears again if the person is not being treated. Is it like that? Does the p24 antigen level increase an...  Read Full »


Dr. Arun Kaushik. R

Answer: Hello, Welcome to icliniq.com. The p24 antigen can be detected faster than antibodies. After two months, as one produces antibodies, the virus will be killed, and the p24 might not be detectable. However, once the antibody level reduces in the body, the antigen can be detected as the viral l...  Read Full »

I have some concerns. Do HIV combo test detect p24 antigen for HIV-2?

Query: Hello doctor, I have some concerns regarding HIV testing. Please answer my questions below regarding the same. Does HIV combo test detect p24 antigen for HIV-2? Do combo tests and antibody tests detect all subtypes and strains of HIV? Can a PCR test detect all subtypes of HIV? Thank you.  Read Full »


Dr. Parth R Goswami

Answer: Hello, Welcome to icliniq.com. Thanks for writing in, and I understand your concern. Based on your attached report (attachments removed to protect the patient's identity) of the human immunodeficiency virus (HIV) combo test, it can detect both 1 and 2 types of HIV virus. As I can see, it is a ne...  Read Full »

What kind of muscle pain is associated with ARS?

Query: Hi, I am a 31 year old male. About 38 days before I had sex with a CSW (Commercial Social Worker). It was protected vaginal sex and protected oral sex. Also there were deep throat kisses which lasted almost a minute. I am not sure if the condom was torn during the intercourse.  Since last 3 weeks ...  Read Full »


Dr. Sidharth Sonthalia

Answer: Hi,  Welcome to icliniq.com. Based upon your history, my answer to your questions: 1. Are My Symptoms Related to ARS? Acute Retroviral Syndrome (ARS) typically begins 7-14 days after the exposure to a HIV positive patient, and may last for up to 3-4 months. The symptoms are typically "flu-l...  Read Full »

Is testing for HIV after 77 days with a rapid test card conclusive?

Query: Hello doctor,I had a protected intercourse with a girl twice in a single day. After that, the girl and I tested HIV negative using the fourth generation CMIA at 66 days. I again tested at 77 days using the rapid card method and that was negative as well. Is it conclusive? Also, can deep lip kissing ...  Read Full »


Dr. Richa Agarwal

Answer: Hello, Welcome to icliniq.com. I have read your query and understand your concern. Yes, the test is conclusive. Deep lip kissing transmits HIV (human immunodeficiency virus) through the saliva. Feel free to ask more information. Good luck. Regards. For further queries consult an obstetrician and g...  Read Full »

Are hot breaths and acidity symptoms of an HIV infection?

Query: Hi doctor, I am having hot breaths, and my eyes feel hot. I have acidity problems. All these problems started after I had sexual intercourse. Is it an indication of HIV? Should I get a western blot test now?  Read Full »


Dr. Murali R

Answer: Hi, Welcome to icliniq.com. Hot breaths and acidity problems are non-specific symptoms and are not related to HIV (human immunodeficiency virus) infection. The risk factors for HIV infection is having sex with unknown partners, whose HIV status is not known, or through blood transmission. If you ha...  Read Full »

Can HIV be transmitted through open wounds?

Query: Hello doctor, I had a small fresh peeling and there was slight bleeding from my nail as I do bite my fingers from time to time, and I fingered a girl who had an orgasm on my finger. Do I have any risk of getting HIV from her? I do not know if her HIV situation was positive or negative?  Read Full »


Dr. Basti Bharatesh Devendra

Answer: Hi,Welcome to icliniq.com.Thank you for the query.There are chances of transmission of HIV by the given description (if open wound). If she is positive, consult your doctor for risk assessment and management.  Read Full »

Is it necessary to take fourth-generation test even if other HIV tests are negative?

Query: Hello doctor,I had protected exposure followed by P24 antigen after 33 days, fourth-generation P24 Ag, HIV 1 and 2 antibodies (CMIA) after 38 days, and then tridot after 93 days. All reports were negative for all the tests. As all the reports are negative and protected exposure, can my HIV status be...  Read Full »


Dr. Ravinder Kaur Sachdeva

Answer: Hi, Welcome to icliniq.com. The answers to your queries are: As you mentioned that it was protected sex, and there was no break or slippage of the condom. The risk of acquisition of HIV in this scenario is non-existent. It is great that your HIV test report at both time points is negative. If the...  Read Full »

Does realtime viral load HIV test result reliable?

Query: Hello doctor, Is real time viral load reliable for HIV test after 14 days of sex encounter? I got normal result. I also did p24 on 15th day and get negative result. Now can I be safe from HIV? I use two condoms at the same time during intercourse and I do not know my partner's HIV status. With othe...  Read Full »


Dr. Ravinder Kaur Sachdeva

Answer: Hi, Welcome to icliniq.com. The answers to your queries are: If you had used the condom consistently and correctly, changed for each sexual act with one person, and it did not break or slipped off during the act and you removed it while the penis is still not soft, your risk of HIV is nonexistent...  Read Full »

Kindly check my HIV reports and explain.

Query: Hi doctor, I have had a possible low risk exposure a year back which is about 53-54 days before this day, this has wrecked my life, the exposure can be best described as follows and I apologize for the graphic nature of the same, no penetration, no oral sex, but the unprotected penis has touched th...  Read Full »


Dr. Ravinder Kaur Sachdeva

Answer: Hi, Welcome to icliniq.com. 1) Yes, the test is conclusive although antibodies take some time to develop. 2) It is good that at least you know your baseline HIV status. 3) You can go for repeat test at three months although the risk was minimal. 4) In future, I suggest you to use precautions...  Read Full »

Is p24 HIV test conclusive after 28 days of exposure?

Query: Hello doctor, I am a 30-year-old man. Recently, I was tested for complete STD checkup with TORCH test. I have a few doubts: Are HIV 1 and 2 with p24 duo test after 28 days window period conclusive? My result is nonreactive. I got a positive result for rubella. CMV and HSV 1 and 2 IgG positive but...  Read Full »


Dr. Sushil Kakkar

Answer: Hello, Welcome to icliniq.com. Fourth generation p24 anti-HIV (human immunodeficiency virus) antibody is conclusive after a window of two to three weeks. So a negative result at 28 days is reliable. A positive IgG (immunoglobulin G) for HSV (herpes simplex virus) 1 and 2 means you have an old in...  Read Full »

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