Can social media help stop the spread of HIV?

In addition to providing other potential benefits to public health, all of those tweets and Facebook posts could help curb the spread of HIV. Although public health researchers have focused early applications of social media on reliably monitoring the spread of diseases such as the flu, a new article tells of a future in which social media might predict and even change biomedical outcomes.

Although public health researchers have focused early applications of social media on reliably monitoring the spread of diseases such as the flu, Sean Young of the Center for Digital Behavior at the University of California, Los Angeles.

"We know that mining social media will have huge potential benefits for many areas of medicine in the future, but we're still in the early stages of testing how powerful these technologies will be," Young said.

With the right tools in place, he says, social media offers a rich source of psychological and health-related data generated in an environment in which people are often willing to share freely.

His recent work on Behavioral Insights on Big Data (BIBD) for HIV offers the tantalizing possibility that insights gleaned from social media could be used to help governments, public health departments, hospitals, and caretakers monitor people's health behaviors "to know where, when, and how we might be able to prevent HIV transmission."

Young details a social-media-based intervention in which African American and Latino men who have sex with men shared a tremendous amount of personal information through social media, including when or whether they had 'come out,' as well as experiences of homelessness and stigmatization. What's more, they found that people who discussed HIV prevention topics on social media were more than twice as likely to later request an HIV test.
In the context of HIV prevention, tweets have also been shown to identify people who are currently or soon to engage in sexual- or drug-related risk behaviors. Those tweets can be mapped to particular locations and related to actual HIV trends.

What's needed now is the updated infrastructure and sophisticated toolkits to handle all of those data, Young said, noting that there are about 500 million communications sent every day on Twitter alone. He and a team of University of California computer scientists are working to meet that challenge now.
Although privacy concerns about such uses of social media shouldn't be ignored, Young says there is evidence that people have already begun to accept such uses of social media, even by corporations looking to boost profits.

"Since people are already getting used to the fact that corporations are doing this, we should at least support public health researchers in using these same methods to try and improve our health and well being," he said. "We're already seeing increased support from patients and public health departments."

Real-life social networking prompts people to get tested for HIV

Old-school face-to-face social networking is a more effective way to identify people with HIV than the traditional referral method, suggests research. The study shows that social networking strategies - enlisting people in high-risk groups to recruit their peers to get tested – is more efficient and targeted than traditional testing and referral programs, resulting in 2-and-a-half times more positive test results.

As many as 20 percent of HIV-positive people are unaware of being infected with the virus, and therefore do not receive vital treatment. In addition to missing out on medications that can improve their prognosis and quality of life, these patients also are more likely to spread the disease to others. Therefore, encouraging people at risk for HIV to get tested is critical.

SNS programs likely are more effective because they are more proactive than traditional counseling, testing and referral (CTR) programs, which are available to anyone who wishes to be tested but do not offer the same motivation as encouragement by peers.

"A limitation of the traditional approach is that many people who are at high risk of HIV never take the initiative to get tested on their own," said Ryan Westergaard, MD, PhD, MPH, lead author of the study and assistant professor of medicine at the University of Wisconsin School of Medicine and Public Health, Madison. "Our study found that using social network strategies, in which we enlist people at high risk to encourage peers in their social networks to get tested, results in a higher proportion of positive HIV tests - making our efforts more effective and allowing us to reach the people who need it most."

In the study, researchers collected data from 45 HIV testing sites in Wisconsin over four years. Through SNS, 54 of 2,169 (2.49 percent) people tested were HIV-positive vs. 440 of 48,318 (.91 percent) of those tested through CTR.

In SNS - which is growing in large cities - people at high risk for HIV are paid an incentive (typically $10 to $20) for every person they refer who gets tested. Some experts are concerned that these programs are costly, but the new research suggests that SNS is worthwhile, because it results in a higher percentage of positive tests.

"Some SNS programs limit the numbers of people a recruiter can refer for testing, based on the assumption that that they're just signing up everyone they know to make more money, even if they're unlikely to be HIV-positive," said Dr. Westergaard. "Our study showed that, on average, the 30th or 40th person referred for testing through SNS had just as high if not a higher probability of having a positive HIV test than the first five or 10 people referred.This suggests SNS can be a cost-effective tool to increase testing in specific high risk pools, such as men who have sex with men and transgender people."

Antiretroviral therapy benefits HIV-infected stimulant users

New clinical research from UC San Francisco shows that 341 HIV-infected men who reported using stimulants such as methamphetamine or cocaine derived life-saving benefits from being on antiretroviral therapy that were comparable to those of HIV-infected men who do not use stimulants.

That said, those who reported using stimulants at more than half of at least two study visits did have modestly increased chances of progressing to AIDS or dying after starting antiretroviral therapy compared to non-users. The data was collected between 1996 and 2012.

"Patients with HIV who use stimulants and other substances often experience difficulties with accessing antiretroviral therapy, partially due to the concerns of healthcare providers that they will not be able take their medications as directed. Findings from this study demonstrate that many stimulant users take their antiretroviral therapy at levels sufficient to avoid negative clinical outcomes. When we look at overall mortality, antiretroviral therapy leads to similar clinical benefits for both stimulant users and non-users, notwithstanding stimulant use," said the study's primary investigator, Adam W. Carrico, PhD., UCSF assistant professor of nursing.

The study included 1,313 HIV-infected men who have sex with men within the Multicenter AIDS Cohort Study, an ongoing nationwide prospective study of HIV infection among men who have sex with men in the U.S.

"If we are to achieve the goals of the President's National HIV/AIDS Strategy and UNAIDS to end the HIV/AIDS epidemic, we will need to treat HIV-positive active substance users for their HIV while encouraging them to stop or reduce their substance use. Programs integrating substance abuse services with HIV clinical care may both improve health outcomes for patients and reduce new infections," said Carrico.

The UCSF Division of HIV/AIDS at San Francisco General Hospital has created an integrated care delivery system that could serve as a model for other clinics, added Carrico. The HIV primary care clinic utilizes a patient centered team care approach that includes substance abuse services for stimulant and opioid users, along with mental health services, all located onsite. STOP, the "stimulant treatment outpatient program," within the clinic provides outpatient substance abuse and mental health treatment integrated with patients' primary medical care.

"The pattern of use varies and the real issue is whether patients can take their antiretrovirals as prescribed. We find that some patients are able to start taking antiretrovirals very reliably before they are able to decrease or stop their stimulant use, which often requires more complex behavioral, emotional, interpersonal and environmental changes. Being in an HIV primary care setting allows us to engage stimulant users even if they are not ready to go to specialty substance abuse programs or support groups," said Valerie Gruber, PhD, STOP director and UCSF professor of psychiatry.

Could there be an end in sight for AIDS?

South Africa is the epicentre of the HIV and AIDS epidemic with a staggering 6.4 million HIV infected citizens. In 1990 the WHO reported just 386 cases in South Africa. Over the next 15 years, despite warnings from scientists and policy makers, a tidal wave of infections ensued.  How can policy and health provision cope to improve the outlook?  A new article strategically examines the whole epidemic and identifies economic, epidemiological, and programmatic points for transition and future improvement.

Until 2001, HIV infection in the developing world amounted to certain death for all but the wealthiest. Development of Antiretroviral (ART) drugs now gives an infected young adult a life expectancy of 60. A massive break through, but each patient needs drugs for up to 30 years, representing a huge burden of cost and an enduring challenge for government and health providers to manage. The high cost of drugs may over reach the South African national health budget in a very few years. New infections outnumber AIDS deaths, increasing the number of people living with AIDS; patients requiring treatment increase faster than funding and the scenario escalates. Can the epidemic ever be managed out of an emergency into a more controlled state?

Prevention is central; only by reducing the rate of new infections can an eventual decline in HIV sufferers be achieved; an economic transition. After this tipping point those newly receiving treatment can outpace new infections; an epidemiological transition. In 2006 programmatic transition took place when newly initiated ART patients exceeded numbers of new patients needing ART. Sustained commitment to prevention and treatment has undoubtedly resulted in attrition of untreated HIV/AIDS patients. In future ART is proposed for a wider group of HIV patients, which the WHO believes will prevent 3 million deaths and 3.5 million new infections. It is clear though that despite this, AIDS and the financial load of ART will be here for many more generations, even if infection rates are brought under control.

The authors note "Although significant progress has been made in combating HIV and AIDS, the end of the epidemic may still be a long way off. However, sustained efforts to expand prevention and treatment programmes, as well as health systems strengthening and innovative financing, will ensure the long-term impact of these transitions."

Stem cell transplant does not cure SHIV/AIDS after irradiation of infected rhesus macaques

A new study reports a new primate model to test treatments that might cure HIV/AIDS and suggests answers to questions raised by the "Berlin patient," the only human thought to have been cured so far.

Being HIV-positive and having developed leukemia, the Berlin patient underwent irradiation followed by a bone-marrow transplant from a donor with a mutation that abolishes the function of the CCR5 gene. The gene codes for a protein that facilitates HIV entry into human cells, and the mutation - in homozygous carriers who, like the donor, have two defective copies - protects against HIV infection.

Several factors could have contributed to the cure of HIV/AIDS in the patient:

1. the ablation of blood and immune cells following irradiation killed all or many of the viral reservoir cells that are not eliminated by antiretroviral treatment (ART);
2. the CCR5 deletion mutation in the donor cells protected them and their progeny from HIV infection;
3. a "graft versus host" reaction occurred, where the transplanted cells and their progeny recognize the host cells as foreign and attacked and eliminated HIV-positive reservoir cells that survived the irradiation.

Guido Silvestri, from Emory University in Atlanta, USA, and colleagues investigated the relative contribution of the irradiation to eliminate the reservoir of HIV-infected cells. The scientists worked with the animal model of Simian Immunodeficiency Virus (SIV, a close relative of HIV that infects primates and causes a disease similar to AIDS) infection in rhesus macaques. Using a total of six monkeys (three of which served as controls and did not receive transplants) they performed, for the first time, hematopoietic stem cell transplantation in rhesus macaques infected with a chimeric simian/human immunodeficiency virus (SHIV) and treated with ART.

The researchers harvested hematopoetic stem cells from three macaques prior to infection (of all six animals) with SHIV. They also treated the macaques with ART to reduce viral load and mimic the situation in human HIV-infected patients on ART. They then exposed the three monkeys from which they had collected hematopietic stem cells to a high dose of radiation. This killed most of their existing blood and immune cells, including between 94 and 99% of their CD4-T cells -- the main target of HIV infection -- in the blood. The irradiation was followed by transplantation of each monkey's own virus-free hematopoietic stem cells. The latter can regenerate the blood and immune cells, and did so in all three monkeys within 3 to 6 weeks. Because the transplanted cells are not from a different donor, no graft versus host disease would be expected, and none was observed.

After that time, the scientists stopped ART in all six monkeys. As expected, the virus rebounded rapidly in the control animals. Of the three transplanted animals, two also showed a rapid rebound. The third monkey developed kidney failure two weeks after ART was stopped and was euthanized. It still had undetectable levels of virus in the blood at that time, but post-mortem analysis showed low levels of viral DNA in a number of tissues, arguing that none of the three transplanted monkeys was cured.

The researchers acknowledge a number of limitations of the study, including the small number of monkeys, and the relatively short period of ART prior to irradiation and transplantation. Nonetheless, they say their study "supports the hypothesis that myeloablative total body irradiation can cause a significant decrease in the viral reservoir in blood cells, even though it was not sufficient to eliminate all reservoirs." Their results, they say, suggest that in the cure of the Berlin patient, "the use of the CCR5 mutant donor and/or the presence of graft versus host disease played a significant role."

Having demonstrated in this first test-of-concept study that total body irradiation and hematopoietic stem cell transplantation in ART-treated SIV-infected rhesus macaques is feasible, the researchers express hope that "further studies using this model will provide critical information for the requirements to cure HIV infection in humans."