infection can theoretically be divided into four different phases, these
phases are not, in practice, as distinct. If you’re HIV positive, your health will
depend on how strong your immune system is, your CD4 cell
count and viral load, and on whether you’ve been exposed
to other infections and diseases.
HIV infection can, however, be divided
into the following broad phases or stages:
Stage 1: The primary HIV infection phase
The acute phase of HIV infection (also called acute seroconversion illness)
begins as soon as seroconversion has taken place. Seroconversion is when your
HIV status converts or changes from being HIV-negative to HIV-positive. Prior
to seroconversion, an HIV test would be negative. Following seroconversion, the
HIV test would show that you’re HIV-positive.
time between the onset of HIV infection and the appearance of detectable
antibodies is known as the ‘window period’. This period lasts for a couple of
weeks. During this time, an HIV test would show that a person is HIV-negative
even though they’ve been infected with the virus. This is why a follow-up HIV
test is always recommended if you have a negative HIV test.
30% - 60% of HIV-infected people develop ‘flu-like symptoms such as a sore
throat, headache, mild fever, fatigue, muscle and joint pains, swelling of the
lymph nodes, rash and (occasionally) oral ulcers. These symptoms usually last
for a week or two.
the virus replicates rapidly, the viral load is usually very high during this
Stage 2: The asymptomatic latent phase
The second phase of HIV infection is the asymptomatic latent or silent phase. During
this stage, an infected person displays no (or very few) symptoms. During this
phase, many HIV-positive people are unaware of the fact that they’re carrying
the virus – unless they’ve had an HIV test and know their status. This means
that they can unwittingly infect new sexual partners.
If you’re HIV-positive and in this
second, latent phase, the virus is still active in your body. Over time,
however, the virus will start to destroy your immune system. The good news is
that most people (especially those who are on ART) remain HIV-positive for many
years without any manifestation of clinical disease.
Stage 3: The minor symptomatic phase of HIV disease
In the third phase of infection, minor and early symptoms usually start to
appear. At this stage, your viral load is increasing, your immune system begins
to fail, and opportunistic infections occur.
If you’re in this phase, you may
- Mild to moderate swelling of the lymph
nodes in the neck, armpits and groin
- Occasional fevers
- Oral candidiasis (thrush)
- Pulmonary tuberculosis
- Oral hairy leukoplakia (causing white
patches on the tongue)
- Shingles (or herpes zoster)
- Skin rashes and nail infections
- Sores in the mouth that come and go
- Recurrent upper respiratory tract
- Weight loss of up to 10% of your usual
- General feelings of tiredness and not
Stage 4: AIDS
The fourth stage is known as Acquired Immunodeficiency Syndrome (AIDS).
Major symptoms and opportunistic diseases begin to appear as
your immune system continues to deteriorate and the viral load gets higher. At
this point, your CD4 count drops significantly (below 200) and your viral load becomes
very high (between 100,000 and 1 million).
The following symptoms usually
indicate advanced immune deficiency:
- Oral and vaginal thrush
infections (thrush) that are persistent and recurrent
- Oesophageal candida (thrush in the
- Extra-pulmonary tuberculosis (TB) that
affects other parts of the body besides the lungs
- Recurrent herpes infections such as
cold sores (herpes simplex)
- Recurrent herpes zoster (or shingles)
- Bacterial skin infections and skin
- Bacterial pneumonia
- Kaposi’s sarcoma, a form of skin
- Pneumocystis jerovici pneumonia (PJP)
– the most common opportunistic infection in people with HIV
- Fever for more than a month
- Persistent diarrhoea for more than a month, leading
to wasting syndromeWeight loss of more than 10% of usual
- Generalised lymphadenopathy, a disease
affecting the lymph nodes (or, in some cases, the shrinking of previously
enlarged lymph nodes)
- Toxoplasmosis of the brain (an
infection caused by a common parasite)
(a common herpes virus)
- Cryptococcal meningitis
(an infection of the tissues covering the brain
and spinal cord)
- Peripheral neuropathy (damage to
the nerves in the hands and feet)
- Abdominal discomfort
- Oral hairy leucoplakia (white patches
on the tongue)
- Persistent cough and reactivation
HIV: What the
CD4 and viral load numbers mean
The CD4 count
CD4 cells are
white blood cells that fight viral and bacterial infections. They’re also known
as T-cells, or T helper cells. HIV targets and infiltrates the CD4 cells in the
human body, tricking the cells into making more copies of HIV. It’s this
mechanism that makes HIV such a tricky virus to control.
Your CD4 count is indicated in cells
per cubic millilitre and is measured by taking a blood sample. A normal CD4
count is between 800 and 1,500 mm3,
although it varies between individuals. If your CD4 count is
decreasing, it means that your immune system is becoming less effective at
fighting off infections.
CD4 cell counts are the best
predictors of the risk of opportunistic diseases in people with HIV/AIDS. A CD4
count below 500 cells per mm3
usually indicates immune suppression and vulnerability to opportunistic
infections. Once your CD4 count drops below 350 cells per mm3 of blood, you need to be
assessed for antiretroviral treatment (ART).
Here is a quick guide to CD4 counts:
500 and 1200 = normal for people who don’t have HIV
350 = HIV treatment isn’t usually recommended
350 = HIV treatment is recommended
200 = There’s a higher risk of illnesses and infections, so HIV treatment is
Note that your doctor may give your CD4 results as a percentage:
29% = similar to a CD4 count of above 500
14% = similar to a CD4 count of below 200
What is ‘viral load’?
The CD4 count
is one measure of HIV progression; the other is viral load. This refers to the amount or concentration of virus in the blood
and is an indication of how sick an HIV-infected person is. The higher the
viral load, the more progressive the HIV disease.
If you’ve recently been infected with
HIV, your viral load is likely to be high. This will decrease over time, as
your treatment kicks in.
The viral load can be “counted” by doing a blood test such as the
Polymerase Chain Reaction (PCR) test,
which measures the number of HIV copies in your blood. The bDNA (branched DNA) and NASBA (nucleic acid sequence based amplification) methods are also used to test viral load. The result is
expressed as the number of copies of HIV per millilitre of blood.
If you’re on antiretroviral treatment (ART), your viral load
should be lower than detectable limits. If the viral load is detectable, it
means that the treatment isn’t working well enough. This could either be
because of non-compliance (i.e. you’re not taking your medication exactly as
prescribed) or because the virus has developed resistance to the drugs.
Here’s a quick guide to viral load count:
- Between 100,000 and 1 million copies = high
- Less than 500 copies = low
- Below 50 copies = “undetectable” (i.e. the virus is
still present, but your treatment is successfully controlling it)
Note that tests made by different
manufacturers might give slightly different results, which is why your doctor
or clinic nurse should use the same type of test every time.
The ‘dance’ between viral load, CD4 count and disease
progression, or the extent to which an HIV-infected person gets sick with
opportunistic diseases and infections, will depend on the viral load as well as
the CD4 cell count. The higher
the viral load, the lower the CD4
cell count – and the higher the risk of infections.
Opportunistic infections associated
with advanced disease are more likely to occur once your CD4 count falls below
350. The types and numbers of infections may also increase as your CD4 count
drops to below 200. This is known as the AIDS phase, and
the viral load now starts to climb to significantly higher levels. The
progression to the final phase of AIDS (and death) will be much faster.
Conversely, a lower viral load goes hand in hand with a higher CD4 cell count, because fewer viruses in the
blood give the immune system a chance to build up its resources again. If you
are HIV-positive and have a low viral load and a high CD4 count, you can remain healthy for years because your
immune system is strong enough to fight off
If you’re HIV-positive, it’s important
to get your CD4 and viral load tests done regularly. These results will give
you essential information about the effect HIV is having on your body. The aim
of HIV treatment is to have a very low or undetectable viral load and a high
The Universal Test and Treat (UTT) policy
in South Africa, treatment started when your CD4 count dropped to 200 or less
or when certain opportunistic infections became evident – whichever came first.
CD4 count for treatment eligibility was later changed to 350. Then, in
September 2016, a universal test and treat (UTT) policy for all HIV-positive
people was introduced. This
means that all HIV-positive children, adolescents and adults, regardless of CD4
count, are offered ART, prioritising those with a CD4 count of 350 or less.
Once treatment is started, there’s normally an increase in CD4 count and a
corresponding decrease in viral load.