Introduction

Human Immunodeficiency Virus-1 (HIV-1) and HIV-2 are lentiviruses.
They are retroviruses that contains all their genetic material as two strands of RNA that have to be converted into DNA by viral reverse transcriptase before the virus can replicate.
'Lenti' = slow, reflecting the long period of time before infection becomes symptomatic.
HIV-1 and HIV-2 both cause Acquired Immunodeficiency Syndrome (AIDS).
HIV-1 has spread rapidly around the world and is much more common than HIV-2.
HIV-2 has remained restricted to west Africa, but has also infected significant numbers of people in India.
HIV-1 and HIV-2 exhibit many common features:
For purposes of simplicity, they will be generically referred to as 'HIV' in these pages.
In 1999 at least 33 million people worldwide were living with either HIV infection or AIDS.
This is a lot fewer than for other incurable viral infections (e.g. Hepatitis B: 170 million, Hepatitis C: 300 million).
But the impact of HIV is far greater in terms of morbidity and mortality.
Currently 95% of HIV infections occur in developing countries.
No effective vaccines against HIV have yet been produced.
In 2000 there were at least 27 different vaccines being tested in clinical trials.
HIV is of direct relevance to the practice of dentistry as:
Appropriate Cross Infection practices will prevent unnecessary spread of HIV infections in the dental surgery.
HIV transmission in the dental surgery is most likely to occur via Inoculation Injuries (needlestick or sharps injuries).
HIV positive patients can remain clinically well for many years without knowing that they are infected.
Oral lesions are common in AIDS and the first clinical suspicion that a patient may be HIV positive can arise during dental treatment.
Most oral lesions (except oral warts) regress with anti-retroviral drugs.
Development of further oral lesions may indicate that the drugs are starting to become less effective in controlling HIV.
The majority of patients who are HIV positive (some of whom will be undiagnosed) can be safely treated in general dental practice.