AIDS stands for Acquired Immunodefiency Syndrome. A person is considered to have AIDS when
their immune system is so damaged by HIV that it can no longer fight off a range of disease with
which it would normally cope. These diseases are known as ‘opportunistic diseases’ and tumours
because they are caused by organisms which ‘take the opportunity’ of a damaged immune system
to cause disease.
AIDS is a result of HIV infection which remains untreated for a long period, but with timely
diagnosis and effective medication AIDS is no longer an inevitable result of being infected with
HIV. Only a small proportion of people with HIV in the UK are now diagnosed with AIDS.
HIV and AIDS are not the same thing. HIV is a virus. AIDS is a clinical description of one or
more diseases which can affect someone who has had their immune system seriously
compromised by HIV. People with HIV can successfully avoid getting AIDS by being diagnosed
in time and taking HIV treatment.
It is not possible to test for AIDS but you can take a test to see if you are HIV positive.
Doctors have agreed a list of opportunistic diseases which are ‘AIDS-defining’ – in other words,
if someone with HIV has one or more of the listed opportunistic diseases they are considered to
have AIDS.
Examples of AIDS-defining illnesses include:
Cryptococcus outside the lungs
Fungus that primarily affected the brain
Symptoms are: headaches, nausea, fever, fatigue, altered mental status and irritability. It can
also cause seizures, coughing, sweats and difficulty in breathing.
Cryptosporidiosos with diarrhoea lasting more than one month
Parasite that can cause diarrhoea
Symptoms are: chronic diarrhoea with frequent watery stools, stomach cramp, nausea, fatigue,
weight loss, appetite loss, vomiting, dehydration and electrolyte imbalance (especially sodium
and potassium)
Cytomegalovirus (CMV) disease outside the liver, spleen or lymph nodes
A virus that can affect many sites in the body
Symptoms might include: (CMV related) retinitis (in eye, retina): blurry vision or loss of central
vision that can lead to blindness. Colitis (colon): fevers, diarrhoea and stomach pain.
Oesophagitis (throat): ulcerations, pain and difficulty in swallowing. Pneumonitis (lungs):
pneumonia-like symptoms. Encephalitis (brain): confusion, fever and tiredness.
Pneumocystsis pneumonia (PCP) Parasite that infects the lungs
Symptoms are: usually fever, cough and difficulty in breathing, occasionally weight loss, night
sweats and fatigue
AIDS is caused by infection with HIV so avoiding HIV transmission is extremely important. HIV
is avoided if you use condoms for penetrative sex and use clean injecting equipment if you are
an injecting drug user.
Even if you have been infected with HIV, you can avoid getting AIDS if you are diagnosed in time
to benefit from the very effective drug treatments which are now available. If you think you may
have been at risk of HIV infection it is important to consider having an HIV test.
You can have HIV for many years without showing a sign of any AIDS-related illness so you must
not wait to be ill before going for an HIV test.
HIV can be passed on through
infected blood, semen, vaginal
fluids or breast milk. The
most common ways HIV is
passed on in the UK are:
- Sex without a condom with
someone already infected
with HIV
- Sharing infected needles
syringes or other injecting
equipment
- From an HIV positive mother
to her child during
pregnancy, childbirth or
breastfeeding. However,
there are steps mothers can
take to reduce very
significantly the possibility
of their unborn or weaning
child contracting HIV.
Oral sex carries a much lower
risk than penetrative sex, but
HIV can still be passed on
through cuts, gum problems or
ulcers in the mouth if they
come into contact with
infected body fluids. HIV
cannot be passed on through:
Kissing or touching, Spitting,
coughing or sneezing, Toilet
seats, swimming pools, or
shared facilities or utensils.
Aids 