HIV Viral load monitoring: from patient to public health issue

Amazing strides have been made in providing access to Antiretroviral Therapy (ART) in resource-limited settings. In 2011, around 8 million HIV-infected patients living in low- and middle-income countries have access to ART compared to just 400,000 a decade a go. Greater access to Antiretroviral drugs (ARVs) is good news, but it has magnified the need for HIV viral load monitoring to properly administer these drugs. A recent Médecins Sans Frontières (MSF) review of data from 12 low- and middle-income countries found that only 2% of patients had ever received a HIV viral load test result, no less received them every 6-months as recommended by the World Health Organization (WHO).

One Hope by Joe Average was used for the XI International AIDS Conference in Vancouver in 1996The direct benefits of HIV viral load testing to the patient are well documented in terms of better outcomes with decreased mortality. That’s why HIV viral load testing has long been a standard part of treatment in middle- to upper-income nations. But if we look beyond the patient, there is an equally compelling public health case to be made for ensuring access to HIV viral load testing in the low- and middle-income countries where the vast majority of HIV patients live. Here are four ways HIV viral load testing protects the public as well as the patient. 

 1. Help clinical resources go further by targeting counseling where it is needed. Some patients will take their medication as instructed – many will not. Noncompliant patients will usually show elevated viral activity which can lead to increases in treatment failure, transmission, comorbidity, drug resistance, and mortality. Counseling has been found to be very effective at helping with adherence issues but is labor intensive.  This can be an enormous strain affecting the entire clinic. With HIV viral load monitoring the clinic can identify noncompliant patients early and more efficiently target counseling only to those who need it. 

 2. Reduce treatment costs by helping less-expensive first-line ART last longer.  HIV mutates at such a remarkable rate that it is a foregone conclusion the virus will eventually be able to resist first-line treatment. The only question is when. If proper concentrations of the drugs are not properly maintained in the blood it makes this job a lot easier for the virus and thus will lead to treatment failure sooner. Monitoring viral load helps identify viral activity and address it before the treatment fails and the patient needs to be moved to a new treatment (if available).  Without viral load measurement, doctors can also misattribute patient symptoms to treatment failure and switch them before it is required. Since first-line ART is always cheaper than second-line treatment (in some cases one-quarter the price), keeping patients on first-line treatment for as long as possible helps resources go further. 

3. Reduce the spread of HIV.  Studies have found that transmission among HIV-infected persons with a viral load below 1,500 copies/ml is rare.  Put simply, if there is no virus circulating in the patient’s blood, then they are unlikely to spread the disease.  So managing HIV viral load can, in itself, contribute to prevention. But you can’t manage what you can’t measure. This is where HIV viral load monitoring contributes. A mathematical model published in the AIDS journal this year demonstrated that routine virological monitoring combined with ART can lead to a 31% reduction in HIV transmission. 

 4. Combat the global problem of HIV drug-resistance. If HIV is allowed to remain active in the presence of drugs meant to suppress it, then it is just a matter of time before it will produce a viable mutation that will be resistant to the drug. We are already seeing this. A 2010 study in resource-limited settings found that in the absence of HIV viral load monitoring, the incidence of drug-resistant mutations following treatment failure is high.  Of course this causes secondary resistance in these patients. But there’s a knock-on effect in that these resistant patients begin spreading a strain of HIV to others that drugs can’t treat. MSF reports that primary resistance in sub-Saharan Africa is already at 5.6% overall. If we look at countries where ART have been dispensed without HIV viral load monitoring for 10 years or longer we see a rate of 12%.  Worse still, the drug-resistant mutations that are being found in newly infected people who have never been on treatment are resistant to both first- and second-line drugs. That’s a trend that could unravel much of the progress made over the last 20 years in the battle against HIV. 

When we look at HIV viral load monitoring from a public health perspective it becomes clear that the issues above are not limited to low- and middle-income countries. First, because any HIV viral load monitoring solution that is inexpensive enough to be viable in resource-limited settings could lower the cost of HIV treatment for any healthcare system. Secondly, because issues like the spread of HIV infection and drug resistance know no borders. HIV/AIDS is a global problem and affordable HIV viral load monitoring is an important part of the solution whether you are in Nairobi, New York, Melbourne, Lusaka, London, Harare or Hong Kong. 

 As access to ARVs grows across low- and middle-income regions, so does the public health imperative to dispense those drugs in a responsible manner with regular HIV viral load monitoring of patients.  As MSF put it, “Funding the implementation of viral load should not be seen as a luxurious and avoidable expense, but should rather be recognized as a necessary and potentially cost-saving addition to current international commitments to scaling up treatment.”  Today, Cavidi and others have the technology to address this public health issue and provide inexpensive, near-patient HIV viral load monitoring where ever it is needed. Doing so will not only serve the patient but protect the public. All we need is the collective will to make it happen. One more reason why the time for HIV viral load testing is now. 

John Reisky de Dubnic

CEO

Cavidi

Further reading:

• Aghokeng AF, Kouanfack C, Laurent C, Ebong E, Atem-Tambe A, Butel C, Montavon C, Mpoudi-Ngole E, Delaporte E, Peeters M: Scale-up of antiretroviral treatment in sub-Saharan Africa is accompanied by increasing HIV-1 drug resistance mutations in drug-naive patients. AIDS 2011, 25: 2183 –2188.
• Estill J, Aubriere C, Egger M, Johnson L, Wood R, Garone D, Gsponer T, Wandeler G, Boulle A, Davies M-A, Hallett T, Keiser O: Viral load monitoring of antiretroviral therapy, cohort viral load and HIV transmission in Southern Africa: A mathematical modelling analysis. AIDS 2012, 26: 1413.
• Hamers RL, Wallis CL, Kityo C, Siwale M, Mandaliya K, Conradie F, Botes ME, Wellington M, Osibogun A, Sigaloff KCE, Nankya I, Schuurman R, Wit FW, Stevens WS, van Vugt M, de Wit TFR: HIV-1 drug resistance in antiretroviralnaive individuals in sub-Saharan Africa after rollout of antiretroviral therapy: a multicentre observational study. Lancet Infect Dis 2011, 11: 750 –759.
• Lynen L, Van Griensven J, Elliott J: Monitoring for treatment failure in patients on first-line antiretroviral treatment in resource-constrained settings. Curr Opin HIV AIDS 2010, 5: 1–5.
• Médecins Sans Frontières: Undetectable – How Viral Load Monitoring Can Improve HIV Treatment in Developing Countries, July 2012
• Murtagh M: UNITAID HIV/AIDS Diagnostic Landscape 2nd Edition. 2012.
• Quinn T, Wawer M, Sewankambo N: Viral Load and Heterosexual Transmission of Human Immunodeficiency Virus Type 1. N Engl J Med 2000, 342: 921–929.