March 5, 2015

March 5, 2015
Primary HIV Infection

Welcome to another day in my life. Today is Thursday and I hope you are having a beary safe and great week so far. Dab the AIDS Bear and I are finally home still recovering from pneumonia and a horrible case of the flu.

Most people have heard about HIV. To live with HIV means at some point you were first diagnosed as having the HIV virus in our body. But what does that mean and when were you infected? Otherwise known as the overlooked period.

The overlooked transmission period

Shifting the dialogue from sexual ‘rules’ to dealing with the virus itself also reveals an extraordinary oversight in risk-reduction programmes: Primary HIV Infection (PHI). PHI is sometimes called Acute HIV Infection, and is commonly referred to as the Window Period.

The following facts concerning PHI are pertinent:

• Fact 1: The highest viral load level ever achieved by HIV during the entire disease progression – reaching levels of up to 1,000,000 particles per millilitre – occurs during the so-called Window Period (PHI).

• Fact 2: This extraordinarily high viral load directly translates into the highest probability of onward transmission during unprotected sex. At no other point of infection is the probability of transmission this high, including during AIDS. According to some studies, the probability of transmitting HIV to another person during PHI is 12 times higher than during AIDS: 1 in 50 to 1 in 2505 sexual acts.

• Fact 3: When a person in the Primary HIV Infection stage is tested for HIV using HIV antibody tests, they test HIV-negative.

What are the implications?

• Up to 50% of all new sexually transmitted infections are caused by people who test HIV negative that are in the Primary HIV Infection period. The precise extent of onward transmission during PHI is unclear, with differences found between studies in the US (9%), Quebec (50%), and Uganda (50%). In the Ugandan study, 43% of those in the PHI stage infected their partners during a ten weeks period before seroconversion, 8% of those in the asymptomatic period infected their partners over one year, and 37% of those with AIDS symptoms infected their partners between 6 months and 3 years before their deaths.

• On average, after infection the viral load peaks in the blood at about day 17, and then peaks in sexual fluids between 28 and 31 days (4 weeks) after infection. Once antibodies are formed, the viral load collapses dramatically. By the time of seroconversion (approximately 10 weeks after infection), the viral load has dropped to 125,000 parts per ml in blood, and 1,000 parts per l in semen.

• Between 50% and 90% of people infected with HIV, who are in the PHI stage, experience clinical symptoms that resemble flu or mononucleosis, but -significantly - without nasal congestion: Fever, maculopapular rash, muscle or joint pains, and night sweats. These symptoms are the most significant predictors of PHI, and are called ARS (Acute Retroviral Syndrome). Other common symptoms (but not significant predictors of ARS) include swollen lymph nodes, a sore throat, diarrhea, and headache. ARS symptoms are nonspecific, and a differential diagnosis for ARS would include mononucleosis, viral hepatitis, secondary syphilis, herpes, and meningitis. ARS symptoms tend to commence anywhere from 2 days to 6 weeks after infection, last on average 14 days, and disappear at the same time as seroconversion from HIV-negative to HIV-positive.

• Many of the people experiencing ARS symptoms seek medical services for their symptoms. Most clinicians are unaware of the significance of PHI and the existence of ARS. Consequently, when patients present with such ARS symptoms they are usually misdiagnosed. Also, no HIV risk assessment is done (checking for recent high risk sexual activities), and – most importantly – the opportunity to advocate risk-reduction behaviors to protect sexual partners is missed entirely.

• Although research is still in its early stage, it appears that the severity of ARS – and the treatment thereof – is a highly significant predictor of the speed of subsequent progression of HIV to AIDS. This relates to the ‘viral set point’ established by HIV during PHI.

• Current HIV testing and counselling procedures do not take ARS symptoms into consideration when assessing risk for HIV. The opportunity for partner-notification and protection when a person tests HIV-negative is lost. Although standard HIV testing protocols advise those who test HIV-negative to return 3 months later to confirm their status, rarely is much time spent on educating the person on the extreme risks associated with being in the PHI period, or what to look out for in terms of ARS.

In developed countries such as the USA, PHI is detected using either PCR or a viral load test. For example, if a person is indeed infected with HIV but is in the PHI period, then a viral load test will detect 97% of such cases: Any viral load above 1,000 is considered evidence for being infected with HIV, even if the antibody test is negative. A cheaper option is the P24 antigen test, which can detect approximately 80% of such cases. It is more accurate when the person is experiencing ARS symptoms, and less accurate once those symptoms subside.

big bear hug,

Daddy Dab