Vaccine FAQ
Here’s some answers to some of the key questions people have about HIV/AIDS
What is a vaccine?
Why do we need an HIV vaccine?
How would an HIV vaccine work?
What is the difference between a preventive vaccine and a therapeutic vaccine?
What are the characteristics of an effective preventive vaccine?
What is an HIV vaccine clinical trial?
What is involved during an HIV vaccine trial?
What are some possible side effects of an experimental HIV vaccine?
Can you get HIV/AIDS from a vaccine study?
Why has the search for an HIV vaccine taken so long?
Realistically, how soon will a vaccine against HIV/AIDS be available?
Do you have any information on How can I get involved in the search for an HIV vaccine?
What is a vaccine?
A vaccine is a substance that teaches the body to recognize and defend itself against bacteria and viruses that cause disease. A vaccine causes a response from the immune system—the body's defense system—preparing it to fight, and also to remember how to fight, if exposed to a specific infection. A vaccine is not a cure, but prevents infection or slows disease progression. Return to top.
Why do we need an HIV vaccine?
Every day about 7,000 people become newly infected with HIV! Even if this infection rate levels off, it is estimated that 45 million people will be infected with the HIV virus by the year 2011. A preventive HIV vaccine could help stem this tide of infections. Return to top.
How would an HIV vaccine work?
An effective AIDS vaccine would teach the body to recognize HIV and provoke an immune response that would defend against the virus if it entered the body. The information on how to defeat the virus would become part of the immune system's memory; the immune system would be prepared to fight back every time it encounters the virus. Return to top.
What is the difference between a preventive vaccine and a therapeutic vaccine?
Preventive vaccines would be designed to prevent HIV-negative people from becoming infected with HIV when exposed to the virus, or if infection occurs, in the case of HIV, stop the disease from progressing as quickly to AIDS. They are not designed to cure AIDS. Therapeutic vaccines would be designed for people already infected with HIV. Used in combination with anti-HIV medications, preventive vaccines would help boost their immune system. Return to top.
What are the characteristics of an effective preventive vaccine?
- Effective for both genders and all racial and ethnic groups
- Protects against all routes of infection (sexual contact, injected drugs, mother-to-child transmission)
- Inexpensive to manufacture
- Easy to transport and store (for use in developing countries)
- Easy to administer to patients
- Effective and long lasting
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What is an HIV vaccine clinical trial?
An HIV vaccine trial is a study to determine the effects of an experimental vaccine on human beings. It is a carefully controlled experiment in which volunteers receive an experimental vaccine candidate to see if it is safe and effective. There are three phases of clinical trials for vaccine studies:
- Phase I trials study side effects and safety.
- Phase II trials look for the most effective dosage and vaccination schedule (time between vaccinations)
- Phase III trials test the protective benefits of the experimental vaccine in thousands of people.
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What is involved during an HIV vaccine trial?
- Every study is different, and studies can last anywhere from 1-4 years.
- If you are interested in participating in a preventive vaccine trial, clinical staff will first ask you basic questions, usually over the phone, to see if you qualify.
- If you qualify, you will come into the clinic where staff will explain the study in detail and conduct a brief physical exam and blood tests (including an HIV test).
- Once in the study, you will be asked questions about your health at each clinic visit, including any side effects you may have experienced and what medications you are taking.
- Usually, blood will be drawn to detect the presence of immunity in your body produced by the vaccine.
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What are some possible side effects of an experimental HIV vaccine?
Generally, side effects do not last long and study volunteers usually do not require treatment. Possible side effects of experimental vaccines could include:
- fever
- chills
- rash
- aches and pains
- nausea
- headache
- dizziness
- fatigue
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Can you get HIV/AIDS from a vaccine study?
No, you cannot be infected by HIV from the vaccine itself. Return to top.
Why has the search for an HIV vaccine taken so long?
HIV vaccine development continues but not without bumps in the road. Development of any new vaccine normally is a long and complicated scientific research process. It usually takes 10 to 15 years and US$100 to $200 million to develop and test a vaccine.
Developing a vaccine to prevent HIV/AIDS is very difficult because HIV is one of the most complicated viruses ever identified. The more we learn about HIV and its behavior, the more complicated the search for a vaccine becomes. HIV targets and destroys the very immune system that a vaccine traditionally triggers. Millions of HIV viruses are constantly produced and they keep mutating. The immune system is unable to recognize and control this endless stream of new forms of the virus. Other scientific challenges to AIDS vaccine development, including the lack of a good models for early testing of candidates in animals and the concern that a single HIV vaccine could even control all the different types of HIV.Return to top.
Realistically, how soon will a vaccine against HIV/AIDS be available?
A preventative HIV vaccine may still be many years away. Each trial is designed to answer key scientific questions on the road to an HIV vaccine by testing the most promising candidates. It may take several trials and a combination of the best vaccine products to protect against HIV infection, control HIV viral replication, or make HIV transmission to a partner impossible. Return to top.
Do you have any information on How can I get involved in the search for an HIV vaccine?
No, you cannot be infected by HIV from the vaccine itself. Return to top.
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