Pharmacists must be up to date with the latest developments in HIV prevention and treatment, writes Louis Roller
The acquired immune deficiency syndrome (AIDS) is the most serious expression of disease resulting from infection with the human immunodeficiency virus (HIV).
A diagnosis of AIDS implies that there has been some damage to the immune system resulting in opportunistic infections or secondary cancers.
Infection with HIV causes a continuum of clinical conditions. These can range from the asymptomatic carrier state to mild-to-more severe AIDS-related conditions to the diseases of AIDS itself (which may take anything from 5-12 years to develop).
Mild-to-moderate states encompass a wide spectrum of disease, e.g. oral hairy leukoplakia, whilst AIDS itself is characterised by more life-threatening opportunistic infections (bacterial, fungal, viral and protozoal), neurological manifestations or secondary cancers). Even in the asymptomatic state, an extremely dynamic situation exists between the immune system and HIV
Throughout the course of HIV infection, the virus continues to replicate rapidly. CD4 cells, the major cells targeted by HIV, are killed and replaced in large numbers, until finally the capacity of the immune system to respond further is exhausted resulting in severe immunodeficiency.
HIV is spread by sexual intercourse, injection of blood, or through mucous membranes contaminated with blood or body fluids, from infected mother to infant; in utero, perinatally, through breast milk and contaminated syringes.
HIV does NOT spread by casual social contact such as touching, hugging and kissing.
Signs and symptoms of HIV infection include: chills and fever, malaise, night sweats, fatigue, dry productive cough, oral lesions, dyspnoea, skin rashes, lethargy, abdominal discomfort, confusion, diarrhoea, stiff neck, weight loss, seizures, lymphadenopathy, headache, progressive generalised oedema.
Opportunistic conditions associated with AIDS include a variety of bacterial, fungal, viral and protozoal infections, as well as some cancers.
Since 1999, there has been a small but significant yearly increase in the number of people newly diagnosed with HIV; more people living relatively well with HIV increases the risk of exposure through unsafe sex.
Some Australian statistics:
This snapshot of the latest HIV data for Australia is drawn from the Kirby Institute’s 2016 Annual Surveillance Report (for the year ending 31 December 2015):
- At the end of 2015, an estimated 25,313 people were living with HIV in Australia, of whom an estimated 2,619 (10%) were unaware of their HIV-positive status. In Australia, HIV transmission continues to occur primarily through sexual contact between men.
- In 2015, 1,025 people were diagnosed with HIV. The number of newly diagnosed HIV infections in Australia has remained stable for the past three years, with 1,025 cases in 2015, 1,082 in 2014, 1030 in 2013 and 1,064 in 2012.
- Over a quarter (29%) of new HIV diagnoses in Australia in 2015 were diagnosed late, emphasing the ongoing importance of regular HIV testing.
- By 31 December 2015, 36,171 cases of HIV had been diagnosed in Australia since the first diagnoses in 1982.
- The annual number of AIDS diagnoses in Australia peaked at 953 cases in 1994. After 1994, AIDS diagnoses declined rapidly due to the introduction of effective antiretroviral therapies which delay progression from HIV to AIDS and few people are now diagnosed with AIDS.
Of all HIV diagnoses made in Australia in 2015:
- 68% of transmissions occurred among men who have sex with men;
- 5% of transmissions were attributed to either male-to-male sex or injecting drug use;
- 20% of transmissions were attributed to heterosexual sex;
- 3% of transmissions were attributed to injecting drug use; and
- for 4% of transmissions, the mode of transmission was undetermined.
One of the testaments to the medical successes in dealing with the virus is the significant number of HIV-positive people living into old age. They are coping with the same crises that beset us all as we get older, but with the additional burden of chronic conditions that interacts unpredictably with other diseases.
A range of antiretroviral agents is now available. There are currently seven categories of antiretroviral drugs: nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), fusion inhibitors, entry or CCR5 antagonists, integrase inhibitors and nucleotide analogues. All of these medications have their own range of adverse reactions and drug interactions.
From 1 July 2015, all pharmacies were able to dispense HIV antiretroviral medicines under the HSD Program regardless of where the medicine is prescribed.
This means that pharmacists in community pharmacy will have been receiving prescriptions for antiretroviral agents and therefor they must ensure that they are right up to date with the therapeutics of these medicines
Additionally PrEP is the use of antiretroviral drugs (emtricitabine and tenofovir disoproxil fumarate), taken by HIV negative people to prevent HIV infection. PrEP is an acronym that stands for pre exposure prophylaxis and is an exciting new tool that will play a vital role in our efforts to end HIV in Australia.
Unlike post exposure prophylaxis (PEP) which is taken after a potential exposure to HIV, PrEP is taken on an ongoing basis and it provides protection against HIV.
Studies from around the world have shown that if PrEP is taken daily, it prevents HIV in advance to any potential exposure. Unfortunately, PrEP tablets are not subsidised on the PBS at this time (November, 2017).
Key steps in preventing HIV include:
- staying educated about HIV and AIDS;
- using latex or polyurethane condoms (male or female) when engaging in any type of sex (anal, oral*, vaginal);
- limiting the number of sexual partners;
- knowing the sexual history of all new partners before engaging in sexual activity;
- avoiding sharing needles with others and using only clean, sterile needles; and
- not sharing any personal instruments with blood residue (e.g, razors).
Readers are referred to the APF 23 which has an excellent section on HIV/AIDs.
*Transmission of HIV is highly unlikely through oral sex
Associate Professor Louis Roller, from the Faculty of Pharmacy and Pharmaceutical Sciences Monash University, was the 2014 recipient of the PSA Lifetime Achievement Award.