You get tested. Testing is the only reliable way to detect HIV.
You 99.9% know when you have HIV when you get an initial HIV test. A positive result will prompt a more formal Western Blot test after which, you will 100% know.
There are no tell-tale symptoms associated with HIV infection. Some people contract a sort of seroconversion sickness about two weeks after contracting HIV from unprotected sex or needle-sharing. Symptoms are virtually identical to the common cold or flu. Thus, it is an unreliable indicator of HIV. And if you ARE using this as an indicator, it's too late to do anything but get a more formal test.
However, there is something called post-exposure prophylaxis. After you are exposed to HIV through unprotected sex or needle sharing/needle stick (WITHIN 72 HOURS), you can take a course of antiretroviral medications (usually, tenofevir and kaletra) religiously for 30 days straight. If you actually had HIV in your body from that exposure (which is usually unlikely), 80% of the time this works. ****NOTE: While post-exposure prophylaxis is available in some countries for free (e.g. the UK), in the US, it can cost as much as $1200.
Long story short -- always use condoms, and certainly don't have sex with people you know to have HIV without using a condom. And there is really no need to share needles, they are virtually free.
You can't, you can't. Be clear on this; you CANNOT tell. Don't let anyone fool you into thinking there is some kind of "method". Even if you ask and the person answers honestly, you cannot tell. Very few HIV+ people become infected intentionally, so that they know instantly when they should start answering the question "yes". Be cautious and remain safe. You can't do a "re-take" after becoming HIV+. See link to left. First things first: IT IS IMPOSSIBLE TO BECOME INFECTED WITH AIDS. AIDS is simply a syndrome that develops as a result of advanced HIV infection. The only way to tell if someone is infected with HIV is for him, or her, to take an HIV test .. and the only way for you to tell if you are infected with HIV is for you to take an HIV test.
No, you will not be infected in that manner.
They look for the bodies antibodies that fight HIV infection to tell if a person is infected with the virus.
HIV-positive means you are infected with the human immunodeficiency virus. HIV-negative means that you are not infected with the HIV.
In order to contract HIV from blood, it must be infected with the virus. Otherwise, you will not contract HIV.
You can not be infected with HIV though casual contact.
Chances are low to be infected with HIV in this manner.
The chances of getting infected with HIV by ingestion of HIV-infected blood is very small.
If you are infected with chlamydia, you will be more likely to be infected with HIV, if exposed.
Not sure if I understand your question. But, the answer is no you cannot get HIV from smoking anything.
A carrier is a person who carries HIV but does not get infected by it.HIV positive is a person that has HIV and gets infected by it.
No. HIV is not transmitted via casual contact.