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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 a few weeks to three months.

Without treatment, HIV will cause damage to your immune system - this will happen in three stages.

Effective treatment will protect your health, enable you to live a normal lifespan, and should lead to you having an undetectable viral load which means you will not be able to pass on HIV. It can take up to six months on treatment to become undetectable.

UK treatment guidelines recommend everyone with HIV starts treatment when they're diagnosed.

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's 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 don't know this has happened at the time.

Seroconversion is the period when someone with HIV is at their most infectious, which means there's 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 passing on the virus and 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.

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 called opportunistic infections. At this stage you may be given a diagnosis of AIDS, although healthcare professionals rarely use this term now.

However, 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 stands for 'acquired immune deficiency syndrome' and 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 soon you start treatment, how well you respond to it and on lifestyle factors that influence your health, such as diet, exercise and smoking.

The UK's treatment guidelines

Everyone with HIV is advised to start treatment as soon as they are diagnosed, whatever their CD4 count. This is because the START trial found that people who waited to start treatment until their CD4 count dropped to 350 (which is when people used to be advised to start) had a significantly higher chance of developing AIDS-related illnesses such as cancers.

People who are on HIV treatment with an undetectable viral load also cannot pass on HIV.

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'll start becoming ill, and may eventually develop late-stage HIV or AIDS. You’ll also be highly infectious and more likely to pass on HIV during unprotected sex.

Someone to talk to about HIV treatment

Whatever stage you're diagnosed at, you'll be advised to start treatment straight away.

This will protect your health and ensure that you cannot pass on HIV. Remember it can take up to six months on treatment for some people to become undetectable.

If you're apprehensive about starting treatment, speak to a member of staff at your clinic. They'll 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.

Remember, treatment will protect your health and others.

More on living with HIV:

‹‹ 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

The Information Standard: Certified member

This article was last reviewed on 20/11/2015 by Anna Peters

Date due for the next review: 20/11/2018

Content Author: Kerri Virani

Current Owner: Kerri Virani

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