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Stages of HIV infection

stages of hiv infection

When you are first infected with HIV, the virus targets important immune system cells called CD4 cells. Your body produces antibodies to try to fight the virus off. This process is called seroconversion and in most people it happens within 45 days of infection.

However seroconversion can take anything from few weeks to three months.

Without treatment, HIV will cause damage to your immune system - this will happen in three stages. Treatment guidelines have recently been updated and they apply to all stages.

What are the stages of HIV infection?

Some people have a short illness soon after they become infected.

This is known as ‘seroconversion illness’ or primary or acute HIV infection.

Common symptoms include:

  • a fever lasting more than a few days,
  • aching limbs,
  • a blotchy red rash,
  • headache,
  • diarrhoea, and
  • mouth ulcers.

In some people seroconversion illness is so mild that it passes without being noticed. Some people mistake it for the flu, but for some people it is more severe and they may need to see a doctor. However, because the symptoms are similar to symptoms of many other conditions, HIV might not be diagnosed at the time.

Most people who become infected with HIV do not know this has happened at the time.

Seroconversion is the period when someone with HIV is at their most infectious, which means there is a greater risk of passing on HIV to another person.

1. HIV infection without symptoms

Once seroconversion is over, most people feel fine and don’t experience any symptoms. This is often called the asymptomatic stage and it can last for several years.

But just because you feel well at this stage doesn't mean HIV isn't doing anything. The virus is still active, infecting new cells, making copies of itself and damaging your immune system’s ability to fight illness.

2. HIV infection with symptoms

The longer you live with HIV without treatment, the greater your risk of developing symptoms. These can be caused by opportunistic infections that take advantage of your weakened immune system, certain cancers or the direct effects of HIV on the body.

When someone gets ill in one of these ways, they are said to have symptomatic HIV.

The longer someone lives with HIV without treatment, the greater their risk of developing symptoms.

3. Late-stage HIV infection

If HIV has a chance to cause a lot of damage to your immune system, you may become ill from certain very serious infections and cancers. At this stage you may be given a diagnosis of AIDS.

But many people have had an illness which has led to them being diagnosed with AIDS, and then completely recovered and lived for many years, even decades, in very good health.

AIDS is not considered a disease, but a syndrome – a collection of different signs and symptoms, all caused by the same virus, HIV. You cannot 'catch AIDS' and there is no 'AIDS test'. An AIDS diagnosis is usually based on the presence of certain illnesses.

Many people never experience late-stage HIV infection. It depends on a range of factors, including how well you respond to treatment and on lifestyle factors that influence your health, such as diet, exercise and smoking.

New treatment guidelines

If you don’t start treatment, damage to your immune system will happen in the three stages described above.

Without treatment, your immune system will become weaker and you will start becoming ill, and may eventually develop late-stage HIV or AIDS.

Patients used to be advised to start treatment when their CD4 count dropped to 350 or lower. But recently the British HIV Association (BHIVA) treatment guidelines have been changed to say that anyone with HIV who is ready to commit to treatment should start regardless of their CD4 count. This reflects the findings of the START study.

START found that people who waited to start treatment until their CD4 count dropped to 350 had a much higher chance of developing AIDS-related illnesses such as cancers.

Starting treatment also reduces the chances that you will pass on HIV.

Watch the stages of HIV video:

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Someone to talk to about HIV treatment

Whatever stage you are diagnosed at, you will be advised to start treatment straight away.

If you are apprehensive about starting treatment, speak to a member of staff at your clinic. They will be able to explore with you the reasons why you do not want to start. You can also contact THT Direct on 0808 802 1221 for support.

More on living with HIV:

Next: How is HIV passed on? ››

‹‹ Previous: Viral load and CD4 count



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  • I had an sexual enxounter about 5 weeks ago and I was bottom. Though he used an condom and said he is negative, now when i think back I remember that he tried to put the condom wrong side then flipped it over and rolled it down. I us regret that I should ask him change it. and after the sex i found my ass bleeded and i read that the condom could possibly contact hiv virus. Now Im so scared that I might be infected. I had an ear infection about two weeks ago and no I have sore throat, I used oralquick tested, it shows I'm negative, but still I'm scared. So could anyone please tell me the chance of me getting hiv?

    Posted 23:23 Sat 01 Dec 2012
  • Hi Swddddddd

    If you call THT Direct on 0808 802 1221
    they will be able to help you. This number is free to call from all UK landlines and most UK mobiles and will not appear on your telephone bill.

    Alternatively you could ask your question anonymously via our Sex Facts page at https://www.tht.org.uk/sexual-health/Get-help-now/Ask-a-question

    Best wishes

    The web team

    Posted 10:06 Mon 03 Dec 2012
  • Why Isn't There A Vaccine For HIV?
    HIV is a retrovirus. That basically means that instead of using DNA like our bodies, it uses a less-stable genetic molecule called RNA. Once it gets inside the cell, the virus uses a protein that it itself makes (called reverse transcriptase) to turn the RNA into DNA, and then the body turns the DNA into protein (I’m simplifying here, but it’s the general idea we’re going for). It turns out that the HIV version of the reverse transcriptase is a really crappy copier. It makes a ton of mistakes and errors. But it’s the error-prone nature that makes HIV so difficult to make a vaccine against.

    Vaccines are basically a way to trick our bodies into thinking we’ve been infected with a virus or bacteria, and causing the immune system to react, so that the next time we’re actually infected with the real virus or bacteria, we’ll be able to respond quicker and stronger. But in order for the vaccine to work, the immune system has to recognize a certain shape. Sometimes it’s a protein on a bacteria, sometimes it’s a protein from a virus, or sometimes it’s a toxin (like tetanus toxin). But in every case, the immune system only responds to shapes it can see on the outside of cells; it can’t respond to anything that’s hiding away inside another cell.

    HIV sits inside a cellular forcefield, called an envelope, when it’s not inside a cell. Like everything else, the envelope shape is coded by the virus. Other viruses have these envelopes, too, and the body can make an immune response against them, recognize them, and get rid of them. But because the HIV is such a crappy copier, the shape of the HIV envelope is constantly changing. So even if your body could respond to one HIV virus shape, there’d be 5,000 other shapes that it hasn’t responded to yet. Some immunologists like to think of HIV as not just one virus, but thousands of different viruses that are all attacking the same targets. So even if we could vaccinate someone against one envelope shape of HIV, there’s nothing to say that the body could fight off a different envelope shape.

    The drugs that slow down HIV (called an “HIV cocktail”) try to stop the virus in lots of directions, and the body even creates more CD4 cells as it detects that others are being killed. But ultimately, the virus wins, and maims the person’s immune system. This leaves the person at risk for all types of infections from bacteria and viruses that normally the immune system clears without our even knowing it.

    The good news is that HIV is preventable. Blood transfusions in the US are safe, and compared to other viruses, HIV isn’t all that contagious. If you practice safe sex, take precautions when you’re around blood, and don’t share needles, you’ll greatly reduce any risks. And research is showing that if pregnant women take certain HIV drugs, they can greatly reduce the odds that the fetus will have HIV, too
    Get more information about HIV here : http://healthdocpoint.com/hivaids-signs-and-symptoms-in-men-and-women

    Posted 10:19 Sat 26 Sep 2015
  • This comment is awaiting moderation

    Posted 09:32 Mon 16 Jan 2017

The Information Standard: Certified member

This article was last reviewed on 23/11/2015 by Anna Peters

Date due for the next review: 23/11/2018

Content Author: Kerri Virani

Current Owner: Kerri Virani

More information:

Route and susceptibility: mucous membranes and target cells, NAM, Aidsmap

Stages of HIV infection, NAM, Aidsmap, October 2013

HIV antibodies, NAM, Aidsmap

BHIVA guidelines for the treatment of HIV-1-positive adults with antiretroviral therapy 2015, Writing Group: Duncan Churchill Chair Laura Waters Vice Chair N Ahmed, B Angus, M Boffito, M Bower, D Dunn, S Edwards, C Emerson, S Fidler, †M Fisher, R Horne, S Khoo, C Leen, N Mackie, N Marshall, F Monteiro, M Nelson, C Orkin, A Palfreeman, S Pett, A Phillips, F Post, A Pozniak, I Reeves, C Sabin, R Trevelion, J Walsh, E Wilkins, I Williams, A Winston

CD4 cell counts, NAM, Aidsmap, Michael Carter, Great Hughson, 25/3/14

No one with an undetectable viral load, gay or heterosexual, transmits HIV in first two years of PARTNER study, NAM, Aidsmap, Gus Cairns, 4/3/14

START trial finds that early treatment improves outcomes for people with HIV, NAM, Aidsmap, Gus Cairns, 27/5/15

New British guidelines recommend treatment for everyone living with HIV, NAM, Aidsmap, Keith Alcorn, 24/6/15

START trial provides definitive evidence of the benefits of early HIV treatment, NAM, Aidsmap, Liz Highleyman, Produced in collaboration with hivandhepatitis.com, 21/7/15

NHS Choices – HIV and AIDS: Symptoms

Nakagawa F et al. Projected life expectancy of people with HIV according to timing of diagnosis. AIDS 25, online edition, doi: 10.1097/QAD.0bo13e32834dcec9, 2011