2 курс / Микробиология 1 кафедра / Доп. материалы / Kartikeyan_HIV and AIDS-Basic Elements and Properties
.pdfResponse to the HIV/AIDS Epidemic in China |
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Tuberculosis is the leading infectious cause of death in China. Every year, about 1.3 million persons are newly infected and 150,000 die due to tuberculosis. It is necessary to implement effective tuberculosis control programmes since the combination of HIV and tuberculosis epidemics would have disastrous effects (WHO, 2005b). There are concerns that the HIV epidemic could diminish economic progress in China (Watts, 2003b).
REFERENCES
Choi K-H, et al., 2003, Emerging HIV-1 epidemic in China in men who have sex with men. Lancet 361: 2125–2126.
Kanabus A., and Noble R., 2006, HIV and AIDS in China. www.avert.org/aidschina.htm. Last updated 2 August 2006.
Ministry of Health, UNAIDS/WHO, 2006, 2005 update on the HIV/AIDS epidemic and response in China, 24 January.
Pilcher H.R., 2003, Stigmatization fueling Chinese HIV. Nature June 20.
Settle E., 2003, AIDS in China: An annotated chronology 1985–2003. www.casy.org/chron/ AIDSchron _111603.pdf
UNAIDS, 2002, HIV/AIDS: China’s titanic peril. Geneva: UN Theme Group on HIV/AIDS in China, pp 1–87.
UNAIDS/WHO, 2005, Aids epidemic update. Geneva: UNAIDS/WHO, pp 1–5, 31–44.
Watts J., 2003a, Hidden from the world, a village dies of AIDS, while China refuses to face a growing crisis. Cited in: Kanabus A. and Noble R., 2006.
Watts J., 2003b, HIV could blunt progress in China, Clinton warns. Lancet 362: 1983.
WHO, 2005a, Summary Country Profile for HIV/AIDS treatment scale-up. Geneva: World Health Organization. www.who.int
WHO, 2005b, Global tuberculosis control: Surveillance, Planning, Financing. Geneva: World Health Organization.www.who.int
Zhang K-L., and Ma S-J., 2002, Epidemiology of HIV in China, BMJ 324: 803–804.
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CHAPTER 29
EPILOGUE
Abstract
The HIV/AIDS epidemic has polarised society and its institutions since it affected marginalised groups and was linked to sexual behaviour and drug use. Initially, the HIV epidemic was typically blamed on foreigners and foreign behaviour. The global response to the epidemic was slow and inadequate for want of socio-political will to deal with the taboos that cause stigma, discrimination, and denial, and to tackle the social precursors of the epidemic such as gender inequalities, poverty, and human rights abuses.
The introduction of highly active anti-retroviral therapy (HAART) represented a turning point. However, HAART created numerous treatment challenges including frequent adverse effects. AIDS activists played a crucial role in driving the agenda for drug research and early access to new medications for critically ill patients and agitated for low-cost ARV drugs. The epidemic has strongly influenced decisions regarding blood-banking procedures. In the developed countries, HIV/AIDS has become a chronic manageable condition and the focus is on managing the toxic effects of ARV therapy and drug resistance. However, in the world’s poorest countries, access to effective ARV therapy is minimal and the epidemic continues to erode the foundations of society with social and economic consequences that would affect future generations. Preventing new infections, developing an effective vaccine, bringing about legal and social reforms, ensuring access to ARV treatment, and strengthening health-care systems of poor countries are among the several challenges for the future.
Key Words
AIDS activism, ACTG, Blood banking, Doha Agreement, Donor support, Food and Drug Administration, Global response, Global Programme on AIDS, HAART, ‘3 by 5’ Initiative, International funding, PEPFAR, Red ribbon, UNAIDS, World Trade Organisation.
29.1 – EARLY YEARS OF THE EPIDEMIC
On 5 June 1981, the (CDC reported five cases of Pneumocystis pneumonia among previously healthy homosexual men (CDC, 1981a). At that time, few would have realised that it was the forerunner of a pandemic that would cause more deaths than the estimated 25 million caused by Black Death in the 14th century. On 3 July 1981, 26 additional cases of the new disease were reported in New York City and California (CDC, 1981b). On 10 December 1981, the New England
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Journal of Medicine published three consecutive articles on a disease with acquired cellular immune deficiency (Gottlieb et al., Siegal et al., and Masur et al., 1981). On 18 June 1982, the first report indicating sexual transmission of the disease was published. Opportunistic infections and Kaposi’s sarcoma were reported in 34 Haitians in the United States and Pneumocystis pneumonia in 3 haemophiliacs in July 1982 (CDC, 1982a; Sepkowitz, 2001). The first case of the new disease was reported from Africa in 1982 and in the following year, a heterosexual epidemic was reported in Central Africa (Kaiser Network, 2006).
In September 1982, the CDC announced the name ‘acquired immunodeficiency syndrome’ and the official acronym ‘AIDS’. Four risk factors were cited: male homosexuality, intravenous drug use, Haitian origin, and haemophilia A. In 1983, the CDC added a fifth risk group: female sexual partners of men with AIDS. The risk groups soon included infants, prisoners, and Africans (Sepkowitz, 2001). On 13 January 1984, AIDS was declared a notifiable disease in the United States for the first time (CDC, 1984). At least one AIDS case was reported from each region of the world by 1985. In 1986, the first HIV cases were reported in Russia and India (Kaiser Network, 2006). The first comprehensive needle exchange programme was established for IDUs in Tacoma, Washington, USA in 1988 (Kaiser Network, 2006).
29.2 – THEORIES ABOUT AETIOLOGY
Numerous theories were put forward by the scientific community regarding the cause of the new disease. These included cytomegalovirus (a potentially immunosuppressive virus); use of amyl nitrite and isobutyl nitrite as sexual stimulants (both known immunosuppressive agents); repeated exposure to another’s sperm triggering an immune response resulting in a condition resembling chronic graft versus host disease and ultimately, opportunistic infections; and general overloading of the immune system and wearing out of the immune system (Sepkowitz, 2001).
People from outside the scientific community suggested that the disease was a punishment for homosexual men and IDUs (Shilts, 1987; Sepkowitz, 2001). Some were unwilling to accept that the disease could be transmitted through heterosexual contact. For example, the spread of the disease in Haiti was postulated to be a result of voodoo practices rather than heterosexual intercourse (Leonidas & Hyppolite, 1983). In 1983, Luc Montagnier and his associates from Pasteur Institute isolated a retrovirus (later to be called “human immunodeficiency virus” or HIV) from patients with AIDS and in the following year, Robert Gallo and his colleagues from the National Cancer Institute (USA) reported that the retrovirus caused AIDS (Sepkowitz, 2001).
Doubts about the viral cause persisted. In 1987, the American philosopher Louis Pascal came up with a highly debatable theory. All the early AIDS cases originated in the Central African countries – Congo, Rwanda, and Burundi. This area was subjected to trials of a live attenuated polio vaccine on 300,000 men, women, and children. Pascal propounded that the vaccine containing the
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attenuated virus, which was grown in monkey kidney cells, may have carried the virus. This theory was based on Dr. Albert Sabin’s report that an unknown virus contaminated such a batch (www.lifepositive.com/aids.html). As late as 1998, there were persons who doubted that HIV causes AIDS. It was postulated that a disease caused by use of recreational drugs was being blamed on a passenger virus (Duesberg & Rasnick, 1998). Improvements in ARV therapy have paradoxically intensified the debate (Stewart et al., 2000; Sepkowitz, 2001). A study in Texas, USA, has reported that about 30 per cent of persons of Latin American or African descent believed that HIV was a government conspiracy to kill minorities (Fact Sheet 158, 2006).
29.3 – SOCIO-POLITICAL CONSEQUENCES
From its very inception, the HIV/AIDS epidemic polarised society and its institutions since the epidemic affected groups that were already marginalised and was linked to sexual behaviour. Till universal precautions in handling blood and body fluids (CDC, 1982b) were introduced, clinicians feared for their own safety in caring for patients with AIDS. Discussions on public health strategies to contain the epidemic created anxieties in the high-risk groups and caused difficulties in striking a balance between the rights of infected persons and the rights of other members of society to be protected from the fatal disease (Gottlieb, 2001). In 1990, NGOs boycotted the International AIDS Conference in San Francisco to protest against US immigration policy that excluded HIV-infected persons. In 1993, US President Bill Clinton signed HIV immigration exclusion policy into law (Kaiser Network, 2006).
As the epidemic continued to devastate one country after another, the lessons learnt about HIV prevention and control in one country were not put to use in others. The HIV epidemic was typically blamed on foreigners and foreign behaviour, just as the French once called syphilis ‘the Italian disease’ and Italians considered it ‘the French disease’. By the time the scale of the epidemic was fully appreciated, the cost in lives and money had increased exponentially (Sepkowitz, 2006).
29.4 – AIDS ACTIVISM
Many agents were studied in the early years of the epidemic for their effectiveness as ARV drugs. The slow nature of the formal clinical trials provoked patients to criticise the medical-industrial complex as uncaring and uncooperative (Arno & Feiden, 1992; Sepkowitz, 2001). Many agents such as Compound Q (Chinese cucumber plant root) and peptide T entered formal clinical trials under pressure from AIDS activists seeking effective therapy. When studied, the agents proved to be ineffective. Charlatans and quacks exploited the growing despair and frustration among AIDS patients by promoting or selling fraudulent and unproven remedies, a phenomenon called “HIV fraud” (Fact Sheet 206, 2006). Due to the absence of effective ARV drugs, the early 1980s were
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demoralising and fatalism settled in. In March 1985, the US FDA licensed an HIV test that detected anti-HIV antibodies (Sepkowitz, 2001).
In 1986, the National Institutes of Health organised the ACTG, now the largest clinical trials group in the United States. The US FDA granted approval for the first ARV drug, ZDV in March 1987. After the initial enthusiasm, many AIDS patients turned against ZDV and alleged that cheap and simple treatments had been overlooked in favour of a mediocre, expensive and toxic agent (Arno & Feiden, 1992; Sepkowitz, 2001). The concept of placebo-controlled trials, overall pace, and sincerity of scientific investigation were among the points of contention between the community of AIDS patients and the medical establishment. In the years after the introduction of ZDV, progress in drug research was very slow, further deteriorating the relationship between physicians and the community of AIDS patients. In the 1990s, the community of AIDS patients and the medical establishment had begun a productive collaboration that remains the hallmark of AIDS care today (Sepkowitz, 2001).
29.5 – THE RED RIBBON
In early 1991, Visual AIDS Artists Caucus in New York conceived the idea for a global symbol in the fight against the HIV/AIDS epidemic. At that time, yellow ribbons were popular in the United States as a symbol of solidarity with soldiers deployed in the First Gulf War (www.hiv.bg). The red ribbon was introduced as the international symbol of AIDS awareness in 1991 (Kaiser Network, 2006). The Red Ribbon International was founded in London on Easter Monday in 1992. The Red Ribbon Foundation was founded in 1993 in memory of Paul Jabara, a singer, song writer, actor, producer, and music theatre composer, who died of AIDS. UNAIDS has incorporated the Red Ribbon into its own logo. Red colour is the symbol of passion, care, and concern towards those affected and for those who care for and support those affected. Red like blood represents the pain caused by deaths due to AIDS. It also represents the anger and helplessness of confronting a disease for which there is no cure. It is also a sign of warning not to ignore one of the biggest problems of our time. The Red Ribbon is intended to be a symbol of hope that the search for a vaccine and cure is successful and it offers symbolic support to those living with HIV. At the International AIDS Conference in Toronto in August 2006, Red Ribbon Awards were presented to five organisations in Thailand, Ukraine, Zimbabwe, Bangladesh, and Zambia to appreciate outstanding community leadership and action that has helped curtail the spread and impact of HIV/AIDS (www.hiv.bg).
29.6 – ADVENT OF HAART
The introduction of HAART represented a turning point (Gottlieb, 2001). The high cost of HAART was offset by savings in other areas, particularly hospital and home-care charges (Sepkowitz, 2001) and quality of life years regained
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(Palmer, 2003). In 1989, the successful prophylaxis of Pneumocystis pneumonia with cotrimoxazole was reported (Shafer et al., 1989). By early 1997, the annual AIDS-related mortality rate declined by 75 per cent since 1995 in the developed world and the incidence of several opportunistic infections had also declined (Pallela et al., 1998; Gottlieb, 2001). ARV therapy also reduced MTCT of HIV (Connor et al., 1994) in countries where it is available. This achievement demonstrates how an investment in basic research can change the natural history of a fatal disease. ARV therapy continues to evolve rapidly in response to the evolution of HIV in a kind of “biologic chess game” (Gottlieb, 2001).
Initially it was hoped that HAART taken continuously for a number of years might lead to the eventual eradication of HIV from the body. HAART was more complex than mono or dual therapy and posed numerous treatment challenges including pill burden, frequent dosing intervals, food restrictions, and numerous adverse effects (Palmer, 2003; Nwokike, 2005). Adherence to prescribed schedules was difficult and sustained adherence was essential for effective treatment. Within a short period of time, treatment failure was reported in about half of the patients. Treatment failure was defined as increasing viral loads in the blood of patients who had received HAART for 1 year or more (Barlett, 2002). Failure rates were highest in those with advanced disease, those with who received ARV treatments before HAART was instituted, and those with less than optimal adherence to treatment (Palmer, 2003). ARV therapy is associated with significant toxic and adverse effects. Lipodystrophy syndrome (characterised by high serum levels of triglyceride, cholesterol, and glucose in combination with loss of fat in limbs and truncal obesity) was first reported in 1993. This has raised concerns about potential for an elevated risk for cardiovascular disease and diabetes. Some of the physical manifestations of the syndrome (notably “buffalo hump” on the upper back and marked loss of facial fat) were conspicuous and stigmatising. These adverse effects occurred most frequently in patients taking protease inhibitors and certain nucleoside analogues such as stavudine (Palmer, 2003).
29.7 – EFFECT ON BLOOD-BANKING
On 16 July 1982, the CDC reported Pneumocystis pneumonia in three persons with haemophilia (CDC, 1982). This raised possibility of contaminated blood supply. Persons with haemophilia are vulnerable to transfusion-related infections, since a single dose of cryoprecipitate contains products from between 1000 and 20,000 donors. By the time a screening test became available in March 1985, HIV had been transmitted to at least 50 per cent of the 16,000 persons with haemophilia in the United States and to additional 12,000 recipients of blood transfusions. The Institute of Medicine, in its investigation, found that limited safety measures had been adopted and that opportunities for more effective interventions had been lost (Sepkowitz, 2001). In the early 1980s, in France and Japan, officials were publicly chastised and prosecuted, and some were
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jailed for their failure to protect patients with haemophilia from contaminated clotting factor concentrates (Gottlieb, 2001).
The lessons from the AIDS epidemic have profoundly influenced decisions regarding blood-banking procedures. Now ten tests are performed on each unit of donated blood in the United States, as compared with the two tests (for syphilis and hepatitis B surface antigen) that were required in 1981. Guidelines are being developed to prevent possible introduction of the agent of bovine spongiform encephalopathy (BSE) (a prion) into the blood supply (Sepkowitz, 2001).
29.8 – THE GLOBAL RESPONSE
The epidemic required a global response that would combine the resources and technical capacities of the wealthy nations with the needs and capacities of the poor nations. Unfortunately, the response lacked the social and political will to confront the taboos concerning sexual behaviour and drug use that cause stigma, discrimination, and denial; and tackle the social precursors of the epidemic such as gender inequalities, poverty, and human rights abuses. Consequently, the response to the epidemic was slow, inadequate, inconsistent, and often inappropriate (Merson, 2006).
The Global Programme on AIDS (GPA), launched by the WHO in 1987 was unable to gather the necessary political will in donor and affected countries. The effectiveness of GPA was compromised by rivalries with other United Nations Organisations (UNO) and increasing preference of wealthy countries for bilateral aid programs. In 1996, the Joint United Nations Program on HIV/AIDS (UNAIDS) was established to lead an expanded multisectoral global response. UNAIDS, initially co-sponsored by six UN agencies (now ten), and was constrained by its limited resources and strategic conflicts among its partners. Moreover, wealthy nations disengaged form the global response to the pandemic as their own AIDS-related mortality rates declined (Merson, 2006).
Around the turn of the millennium, multiple events contributed to generating the long-needed global response advocated by UNAIDS. Since 1998, the World Bank increased loans for AIDS-related programmes. In 2000, the XIII International Conference in Durban (South Africa) raised global public consciousness about Africa’s AIDS-related mortality and the need for affordable ARV drugs. Around the same time, Brazil reported dramatic reduction in AIDSrelated mortality as a result of ARV therapy, providing hope for other developing nations (Merson, 2006).
AIDS activists had a central role in driving the agenda for drug research and early access to new medications for critically ill patients (Sepkowitz, 2001). NGOs agitated for low-cost generic ARV drugs and price reductions for brandname products (Merson, 2006). In 2001, the World Trade Organization (WTO) announced the Doha Agreement, allowing developing nations to buy or manufacture generic ARV drugs (Kaiser Network, 2006). In April of that year, the
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pharmaceutical industry abandoned its legal efforts to block South Africa from importing cheaper generic ARV drugs (Swarns, 2001).
Politically powerful religious groups that had been reluctant to support condom distribution and other sex-related programmes accepted the need for global treatment, mainly to reduce the number of children being orphaned by the AIDS epidemic. The high sero-prevalence of HIV in some countries and the spread of HIV into Russia, China, and India raised concerns that the AIDS epidemic could threaten the political stability of entire nations, destabilise global political and economic systems, threatening global security (Merson, 2006). On 10 January 2000 the Security Council of the United Nations discussed the possibility that AIDS may threaten the world’s security by devastating a country’s entire population of young adults. This marked the first time that a medical illness received attention of the Security Council (Sepkowitz, 2001).
In January 2003, US President George W. Bush announced the President’s Emergency Plan for AIDS Relief (PEPFAR) and pledged US$15 billion over a period of 5 years. The objective of PEPFAR is to prevent seven million new HIV infections, treat at least two million HIV-infected persons and care for 10 million HIV-infected individuals including AIDS orphans, and vulnerable children. It will focus on 15 countries that are home to 80 per cent of the people requiring ARV treatment (Merson, 2006; FDA, 2006).
In 2003, the WHO announced the ‘3 by 5’ initiative to extend ARV therapy to three million persons in developing countries by 2005. This ‘3 by 5’ initiative fell short of its target but resulted in ARV treatment for 1.3 million individuals, preventing an estimated 250,000 to 350,000 deaths (Merson, 2006).
In 1986, the average interval between a drug application and the granting of approval by the US FDA was 34.1 months; by 1999 it had decreased to 12.6 months (Sepkowitz, 2001). In May 2004, the FDA announced an expedited review process for ARV drugs (FDA, 2006). In 2005, the Indian pharmaceutical Ranbaxy gained approval of the US FDA to manufacture generic ARV drugs for PEPFAR (Kaiser Network, 2006). In 2005 alone, US$8.3 billion was spent on HIV/AIDS – about 30 times as much as at the time of establishment of UNAIDS (Merson, 2006; UNAIDS, 2006).
29.9 – TWO EPIDEMICS
Since the dawn of the 21st century, there is a widening gap between the rich and poor countries so that a single virus is responsible for two epidemics (Sepkowitz, 2006). In the high-income countries, the disease has metamorphosed from being predictably fatal to a chronic manageable condition for individuals in whom the ARV drugs work well (Palmer, 2003) and the focus is on managing the toxic effects of ARV therapy and drug resistance (Sepkowitz, 2006).
In the world’s poorest countries, access to effective ARV therapy is minimal and the epidemic continues to erode the foundations of society with social and economic consequences that would affect generations. The main concerns are
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more basic – HIV prevention, diagnosis, access to health care, and palliation (Palmer, 2003). The intertwined epidemics of HIV and tuberculosis continue to devastate. One-third of the increase in cases of tuberculosis since 2001 can be attributed to the HIV epidemic (Sepkowitz, 2006). Despite the recent gains, it is estimated that only one in ten Africans and one in seven Asians in need of ARV treatment were receiving it in mid-2005 (UNAIDS/WHO, 2005).
HIV infection in children is becoming increasingly rare in the developed world because ARV treatment usually prevents transmission of the virus from mother to child. However, the infection is widespread among children in poor countries of the world where HIV-infected mothers and their newborns are not treated (Steinbrook & Drazen, 2001).
29.10 – STRATEGIES FOR PREVENTION
Each mode of transmission requires a different prevention strategy and each raises different sets of complex issues. For example, an HIV-positive mother who is advised not to breastfeed may face social stigma (Sepkowitz, 2001). Prevention programmes must involve the community and be evidence-based (not moralistic), locally planned, and linked to efforts to reduce stigma and elevate the status of women (Merson, 2006). Though behavioural prevention strategies have been found effective, HIV prevention services currently reach less than 10 per cent of the persons at risk. It is estimated that expanding these strategies worldwide would avert more than half of the new HIV infections projected to occur by 2015 and save US$24 billion in treatment costs (Stover et al., 2006; Merson, 2006).
Viral heterogeneity, uncertainty about how to achieve optimal immunogenicity, lack of practical animal model and ethical dilemmas involved in conducting trials are among the difficulties faced by scientists in developing a vaccine against HIV (Sepkowitz, 2001). Until an effective preventive HIV vaccine is available, HIV prevention strategies must rely on other options. Two effective interventions have been shown to limit the spread of HIV – sex education (including condom promotion) and treatment of drug abuse (including provision of clean needles). Implementation of these programmes continues to be constrained by personal, social, and political barriers in almost all countries and governments. Reluctance to implement effective control measures is responsible for the continued spread of HIV rather than the lack of an effective vaccine or remedy (Sepkowitz, 2001).
There is a need for research on new approaches in prevention. Adult male circumcision, pre-exposure ARV prophylaxis in high-risk groups, acyclovir treatment for herpes simplex type 2, and microbicidal agents seem promising (Merson, 2006). The effect of adult male circumcision on HIV transmission remains controversial despite a report from South Africa, where a 61 per cent reduction in rate of new infection was observed in the circumcision group, as compared with the control (observation) group. The study was conducted on
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more than 3,000 men and the results were controlled for differences in condom use, sexual behaviour, and health-care seeking behaviour (Auvert et al., 2005).
29.11 – THE FUTURE
Preventing new infections, developing an effective vaccine, strengthening healthcare systems of poor countries are among the several challenges for the future. It is also necessary to bring about legal and social reforms to address gender inequalities and the potential for vulnerability, discrimination, and stigma related to HIV infection (Steinbrook & Drazen, 2001). The current debate focuses on whether legal provisions in some countries impede the public health response to the HIV/AIDS epidemic by outlawing certain types of sexual behaviour.
In the United States, approximately one million individuals were infected with HIV in 2003 and an estimated 164,000 to 312,000 of them were unaware of their infection (Glynn & Rhodes, 2005). Most of the 40,000 new HIV infections that occur annually in the United States may be due to contact with these undiagnosed persons.
In September 2006, the CDC, Atlanta, recommended that HIV screening be made routine part of medical care for all patients between the ages of 13 and 64 and to improve diagnosis of HIV infection among pregnant women. Patients are to be specifically informed that they have the opportunity to decline HIV testing. CDC has recommended that written consent for HIV testing be no longer required though HIV testing must be voluntary and undertaken only with the informed consent of the patient (www.boston.com, 2006). The availability of a rapid oral test has simplified mass screening. However, it is feared that routine testing would erode patient confidentiality by eroding legal safeguards (Sepkowitz, 2006).
Eradication of HIV by continuous ARV treatment is highly unlikely with the available drugs due to the very long half-life and latency of some HIV-infected cells of the immune system. ARV therapy has become increasingly complex and clinicians must confront numerous issues and dilemmas. Due to adverse effects of ARV treatment, clinicians have become more cautious in advocating early treatment in contrast to the “hit hard and early” approach initially adopted with HAART (Palmer, 2003; Sepkowitz, 2006). The current American, British, and Australian guidelines for starting ARV therapy are much more conservative than those released in 1997 (Palmer, 2003). Till date, there is no established remedy for common side effects of ARV, such as lipodystrophy, lipoatrophy, diabetes, glucose intolerance, insulin resistance, and dyslipidemia (Sepkowitz, 2006).
Ensuring adherence to free ARV therapy does not guarantee adherence. National ARV programmes need to develop adherence measurement and monitoring systems which are built into the national treatment protocols (Nwokike, 2005). The introduction of once-daily dosing regimens has made ARV treatment more convenient for HIV-infected individuals. Though enfuvirtide is effective against drug resistant strains of HIV, twice-daily injections are difficult to sustain for some individuals. Tenofovir, with or without emtricitabine, reduces