HIV and AIDS - Some Facts

For useful leaflets and brochures about HIV and related health issues, please see the NAM website at

What is HIV?

What is AIDS?

What are the symptoms of HIV infection?

How is HIV passed on?

How can HIV infection be prevented?

Can you treat HIV and AIDS?


What is HIV?
HIV stands for: Human Immunodeficiency Virus
HIV is a virus that infects cells of the human immune system and destroys or impairs their function. Infection with this virus results in the progressive deterioration of the immune system leading to immune deficiency.

HIV is a notifiable disease in Ireland since September 2011.

What is AIDS?
AIDS stands for: Acquired Immune Deficiency Syndrome

AIDS is a medical condition. A person is diagnosed with AIDS when their immune system is too weak to fight off infections and they develop an AIDS related condition or symptom, called an opportunistic infection, or an AIDS related cancer. The infections are called ‘opportunistic’ because they take advantage of the opportunity offered by a weakened immune system. It is possible for someone to be diagnosed with AIDS even if they have not developed an opportunistic infection. AIDS can be diagnosed when the number of immune system cells (CD4 cells) in the blood of an HIV positive person drops below a certain level.

What are the symptoms of HIV infection?
Some people experience a flu-like illness, develop a rash, or get swollen glands for a brief period soon after they become infected with HIV. However, these are also common symptoms of other less serious illnesses, and do not necessarily mean that a person has HIV.

Often people who are infected with HIV don't have any symptoms at all and may appear completely healthy for a long period of time. It is important to remember that a person who has HIV can pass on the virus immediately after becoming infected, even if they feel healthy. It's not possible to tell just by looking if someone has been infected with HIV.

The only way to know for certain if someone is infected with HIV is for them to be tested. The HIV antibody test looks for the presence of antibodies (disease-fighting proteins) to the virus in a person’s blood. Someone with HIV antibodies is infected with the virus. (An exception to this is when transfer of mother’s antibodies to her newborn baby occurs. The baby then has HIV antibodies but has not necessarily been infected). It can take up to 6 months after infection for the antibodies to show up in a test.

How is HIV passed on?
HIV is found in the blood and the sexual fluids of an infected person, and in the breast milk of an infected woman. HIV transmission occurs when a sufficient quantity of these fluids get into someone else's bloodstream.

There are various ways a person can become infected with HIV:

  • Unprotected sexual intercourse with an infected person: Sexual intercourse without a condom carries the risk of HIV infection.
  • Contact with an infected person's blood: If sufficient blood from somebody who has HIV enters someone else's body, then HIV can be passed on in the blood.
  • Use of infected blood products: Many people in the past have been infected with HIV by the use of blood transfusions and blood products which were contaminated with the virus. In much of the world this is no longer a significant risk, as blood donations are routinely tested for HIV.
  • Injecting drugs: HIV can be passed on when injecting equipment that has been used by an infected person is then used by someone else. In many parts of the world, often because it is illegal to possess them, injecting equipment or works are shared.
  • From mother to child: HIV can be transmitted from an infected woman to her baby during pregnancy, delivery and breastfeeding.

HIV is not passed on through everyday social contact with an infected person. Touching, shaking hands, hugging, coughing or sneezing cannot pass on the virus.

Certain groups of people, such as injecting drug users, sex workers, prisoners, and men who have sex with men (MSM) have been particularly affected by HIV. However, HIV can infect anybody, and everyone needs to know how they can and can't become infected with HIV.

How can HIV infection be prevented?
Despite considerable investment and research, there is currently no HIV and AIDS vaccine, and microbicides (designed to prevent HIV being passed on during sex) are still undergoing trials. However, there are other ways that people can protect themselves from HIV infection, which are the basis of HIV prevention efforts around the world.

Some key ways to prevent HIV transmission:

  • abstain from sex, or practice safe sexual behaviors such as using condoms;
  • get tested and treated for sexually transmitted infections, including HIV;
  • avoid injecting drugs, or if you do, always use new and disposable needles and syringes; and
  • ensure that any blood or blood products that you might need are tested for HIV.

Effective sex education is important for providing young people with the knowledge and skills to protect themselves from sexual transmission of HIV. Comprehensive sex education should develop skills and attitudes that encourage healthy sexual relationships, as well as provide detailed information about how to practise 'safer sex'.

Can you treat HIV and AIDS?
Currently there is no vaccine or cure for HIV or AIDS. However over the last 15 years, a number of drugs have been developed which fight HIV infection. A very effective treatment regimen, namely highly active antiretroviral treatment (HAART), is widely used in the treatment of HIV and AIDS. The term HAART is used to describe a combination of three or more anti-HIV drugs. This treatment suppresses the HIV virus and can reverse the damage to the immune system for some time, prolonging the lives of those infected. The virus is continually changing, sometimes becoming resistant to current drugs, so HAART may not be a long-term solution and is not a cure. The treatments are complex and often have side effects.

HPSC produces detailed reports on HIV and AIDS in Ireland 

Last updated: 15 January 2013