HIV
HIV (Human Immunodeficiency Virus) is a virus passed through bodily fluid exchange, typically during intercourse. It is a life-long infection as it’s impossible to clear it from your system, even when treated with drugs that target the virus.
HIV is like a lot of other viruses in as much that the initial symptoms are flu-like. This may include swollen glands, a rash, or generally feeling drained. Your immune system then kicks in and the symptoms go away—so it can be easy to miss. Further, not everyone reacts the same way to an infection of HIV, and symptoms may initially be subtle.
As such, it is understandable that people can go years without knowing they are infected. In fact, over one quarter (29%) of new Australian HIV diagnoses in 2015 were ‘late’, meaning that patients were likely living with HIV for at least four years before being tested.
Unlike most other viruses, it is cells of the immune system that the HIV particles infect. Yes—the very system that helped remove the viral particles from a patient’s blood so they feel better, then lets the viral particles in where they want to go.
The viral particles primarily infect cells called ‘CD4 helper T cells’. Among other things, these cells are responsible for helping to recruit other parts of the immune system to respond to infections.
Once the virus enters a cell and the outer, protective layer of the HIV particle is discarded, the genetic information carried by the virus can be transformed into DNA that is then inserted into the genome of the cell for life. From here, the viral segment of embedded DNA is read by the cell’s molecular machinery that then build lots of copies of each of the building blocks of the virus.
The infected cell essentially becomes a viral factory, generating new viral particles and releasing them to start the cycle of infection and production over again in other cells. The infected cell will die through this process, but there are enough new viral particles generated to enable viral spread.
Over time (often up to seven years without therapy), the number of CD4 helper T cells drops so low that they are almost undetectable in the blood, weakening the immune response to infection from other pathogens. This is what makes untreated HIV lead to AIDS (or Acquired Immunodeficiency Syndrome). Without the CD4 helper T cells, eventually, a simple cold or bacterial infection can be fatal.
While a vaccine remains elusive, there has been a lot of medical progress in the last three decades, and patients with an early diagnosis of the infection (along with access to current antiviral drug treatments) can expect to have a relatively normal life. In fact, an HIV positive person today who is on effective treatment can live as long and be as healthy as a person who does not have HIV. With treatment, the viral load in patients can be reduced and maintained at such a low level, the risk of transmitting the virus to someone else can be almost eliminated.
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If you are sexually active, get regular testing (even if you use condoms) and if you find out you or a partner is positive, seek treatment. The infection is entirely manageable with a relatively simple treatment plan put together by your medical doctor. Not only can further transmission of the virus be prevented, but the long-term damage to the immune system caused by a chronic HIV infection can be avoided.
Finally, if you’re in a group that is at higher risk of acquiring the virus (including anyone sexually active with someone in the LGBQTI+ community), there is an exciting prevention medicine that is showing amazing promise. This pre-exposure medicine, along with effective post-infection management, is hoped to help Australia reach zero HIV transmissions by 2020.