Macalino GE, Mitty JA, Bazerman LB, Singh K, McKenzie M, Flanigan T.
YRG Centre for AIDS Research and Education, VHS,
Modified directly observed therapy for the treatment of HIV-seropositive substance users: lessons learned from a pilot study. Clin Infect Dis 2004; 38 (suppl 5): S393–97.
Mahajan AP, Hogan JW, Snyder B, et al. Changes in total lymphocyte count asa surrogate for changes in CD4 count following initiation of HAART:
I am the principal investigator for ACTG/NIH trials for the Chennai site.
implications for monitoring in resource-limited settings.
Palella FJ, Delaney KM, Moorman AC, et al. Declining morbidity and mortality
J Acquir Immune Defic Syndr 2004; 36: 567–75.
among patients with advanced human immunodeficiency virus infection.
Badri M, Wood R. Usefulness of total lymphocyte count in monitoring highly
N Engl J Med 1998; 338: 853–60.
active antiretroviral therapy in resource-limited settings. AIDS 2003; 17:
Kumarasamy N, Solomon S, Flanigan TP, Hemalatha R, Thyagarajan SP,
541–45.
Mayer KH. Natural history of human immunodeficiency virus disease in
Balakrishnan P, Mandy Dunne, Kumarasamy N, et al. An inexpensive, simple
Southern India. Clin Infect Dis 2003; 36: 79–85.
and manual method of CD4 T-cell quantitation in HIV infected individuals for
Remien RH, Bastos FI, Berkman A, Terto V Jr, Raxach JC, Parker RG. Universal
use in developing countries. J Acquir Immune Defic Syndr (in press).
access to antiretroviral therapy may be the best approach to ‘Do no harm’ in
Josefowicz S, Buchner L, Epling CL, Sinclair E, Bredt B. Simple, low-cost CD4+
developing countries: the Brazilian experience. AIDS 2003; 17: 786–87.
T-cell assay: comparison of the Guava Easy CD4 and the BD Biosciences
Kumarasamy N, Solomon S, Chaguturu S, et al. The safety , tolerability and
MultiTest assays for the determination of CD4+ T-cell counts in
effectiveness of generic antiretroviral drug regimens for HIV-infected patients
HIV-1-seropositive and -seronegative volunteers. 11th Conference on
in south India. AIDS 2003; 17: 2267–69.
Retrovirus and Opportunistic Infections, San Francisco, February 8–11, 2004:
Hosseinipour M, Namarika D, Magomero K, et al. The Malawian antiretroviral
program: the first year experience with Triomune. 10th conference on
Malmsten A, Shao XW, Aperia K, et al. HIV-1 viral load determination based
retroviruses and opportunistic infections, Boston, Feb 10–14, 2003: 172
on reverse transcriptase activity recovered from human plasma. J Med Virol
2003; 71: 347–59.
Henry K, Brundage R, Weller D, Akinsete O, Shet A. Comparison of generic
Schupbach J, Tomasik Z, Nadal D, et al. Use of HIV–1 p24 as a sensitive,
zidovudine + lamivudine (Cipla, Duovir) and the GlaxoSmithkline Brand
precise, and inexpensive marker for infection, disease progression and
(Combivir) tablets. J Acquir Immune Defic Syndr 2004; 35: 537.
treatment failure. Int J Antimicrob Agents 2000; 16: 441–45.
Kumarasamy N, Flanigan TP, Solomon S, et al. Rapid viral load suppression
Crommentuyn KM, Mulder JW, Sparidans RW, Huitema AD, Schellens JH,
following generic HAART in Southern Indian HIV-infected patients.
Beijnen JH. Drug -drug interaction between itraconazole and the antiretroviral
XV International AIDS Conference, Bangkok, Thailand, July 11–16, 2004:
drug lopinavir/ritonavir in an HIV-1-infected patient with disseminated
histoplasmosis. Clin Infect Dis 2004; 38: e73–75.
Chesney M. Adgerence to HAART regimens. AIDS Patient Care STD 2003; 17:
Pozniak A. Mycobacterial diseases and HIV. J HIV Ther 2002; 7: 13–16.
169–77. Concurrent sexual partnerships help to explain Africa’s high HIV prevalence: implications for prevention
See Seminar page 69
As Kiat Ruxrungtham and colleagues describe in today’s Lancet,
What might account for this pervasive discrepancy? The
HIV transmission in most Asian countries remains strongly
strong association between lack of male circumcision and HIV
associated with particularly high-risk activities—ie, injection-drug
risk8–10 helps explain the 4–5-fold difference in HIV rates
use, male-male sex, prostitution and, in China, paid donation of
between southern and western Africa discussed by Asamoah-
plasma. Although there is understandable concern that the virus
Odei and colleagues. However, that association does not
could soon spread widely through the general population,1,2 HIV
explain why HIV has spread so much more extensively in
has been present in Asia for nearly two decades and such
southern Africa than in India, or in Europe, where circumcision
extensive spread has yet to occur . For example, analysis of trends
is similarly uncommon. Although sexual cultures do vary from
in India suggests that HIV prevalence, both in high-risk groups
region to region,11 the differences are not so obvious.
and in the generally low-risk antenatal clinic population, has
Demographic surveys and other studies suggest that, on
probably stabilised in recent years.3 It is possible that large-scale
average, African men typically do not have more sexual partners
heterosexual epidemics will never emerge in most of Asia, except
than men elsewhere. For example, a comparative study of
perhaps on the island of Papua.4–6 Furthermore, in some of the
sexual behaviour found that men in Thailand and Rio de Janeiro
world’s most populated countries—Pakistan, Bangladesh, Indo-
were more likely to report five or more casual sexual partners in
nesia, and the Philippines, home to some one billion people—
the previous year than were men in Tanzania, Kenya, Lesotho,
nearly all men are circumcised, further restricting the potential
or Lusaka, Zambia. And very few women in any of these
countries reported five or more partners a year.12 Men and
See Articles page 35
In chilling contrast, as Emil Asamoah-Odei and colleagues
women in Africa report roughly similar, if not fewer, numbers of
report, also in today’s Lancet, HIV rates remain very high in much
lifetime partners than do heterosexuals in many western
of east and especially southern Africa. The overwhelming burden
countries.13–15 Of increasing interest to epidemiologists is the
of HIV/AIDS is still concentrated in this region, which accounts
observation that in Africa men and women often have more
for only 3% of the global population yet some 50% of global HIV
than one—typically two or perhaps three—concurrent partner-
cases.1 For example, infection rates in adults in South Africa,
ships that can overlap for months or years (figure). This pattern
Botswana, Zimbabwe, and western Kenya range from 20 to 40%,
differs from that of the serial monogamy more common in the
roughly an order of magnitude higher than anywhere else in the
west, or the one-off casual and commercial sexual encounters
www.thelancet.com Vol 364 July 3, 2004
Morris and Kretzschmar16 used mathematical modeling to com-
pare the spread of HIV in two populations, one in which serial
monogamy was the norm and one in which long-term concurrency
was common. Although the total number of sexual relationships was
similar in both populations, HIV transmission was much more rapid
with long-term concurrency—and the resulting epidemic was ten
times greater. The effect of such concurrency on the spread of HIV
is exacerbated by the fact that viral load, and thus infectivity,10 is
much higher during the initial weeks or months after infection.17
Therefore, as soon as one person in a network of concurrent
relationships contracts HIV, everyone else in the network is placed
at risk. By contrast, serial monogamy traps the virus within a single
Morris subsequently studied sexual networks in Uganda, Thai-
land, and the USA.14 She found that Ugandan men reported
fewer lifetime sexual partners than Thai men, but while the Thais
mainly had one-off encounters with prostitutes, the Ugandanmen’s relationships tended to be of much longer duration. Given
that the per-act probability of heterosexual HIV transmission is,
on average, quite low, the much higher number of cumulative
sexual acts—and hence the likelihood of transmission—within
any given relationship was much greater in Uganda than in
Thailand or the USA. In addition, except for prostitutes, very few
Asian women have concurrent partners, whereas a larger
proportion of African women do. Even though the Ugandan
women in Morris’ study reported fewer concurrent relationships
than Ugandan men, the multiple partnerships that some of them
did have helped maintain the extensive interlocking sexual
networks which facilitate the generalised spread of HIV.14
Although most African women in concurrent partnerships are
not prostitutes, such relationships often include a quasitrans-
actional aspect, related to issues of gender inequality, poverty,and the globalisation of consumerism.18,19
These patterns of sexual behaviour might have important
implications for HIV prevention. As Ruxrungtham and colleagues
Figure: Frequency of concurrent and suspected concurrent sexual relationships
discuss, consistent use of condoms has been effectively prom-
Percentage of 15–49-year-olds reporting more then one regular partner or spouse
oted in Asia’s organised brothels, particularly in Thailand and
(bottom), and percentage of those who believe that their partner has other regularpartners (top). NA=data not available, CAR=Central African Republic. Redrawn
Cambodia, and, for example, in the Sonagachi project in Cal-
cutta20 and among west-African sex workers in Abidjan andSenegal.21–23 Yet from the gay communities of Australia and San
Although no simple solution exists to this complex problem,
Francisco to the market towns of Uganda, it has proved much
we believe that in addition to condom availability and other pre-
more challenging for people in ongoing longer-term relation-
vention approaches in Africa, there needs to be franker
ships to consistently use condoms.19,22–25 Unfortunately in
discussion and concerted public-health efforts addressing the
Africa—unlike in most of Asia—such longer-term relationships
dangers of having more than one long-term sexual partner at a
are often the ones in which HIV transmission takes place. For
time. Because most Africans do not have exorbitant numbers of
years, condom promotion has been a mainstay of donor-funded
partners, they may not fully realise how dangerous, especially in
HIV prevention in Africa, but a recent review commissioned by
regions of high HIV-prevalence, such behaviours actually are. In
UNAIDS22 concluded that, although condoms are highly effective
southern Africa, even people with only two lifetime partners—
when used correctly and consistently, “no clear examples have
hardly high-risk behaviour by western standards—need to
emerged yet of a country that has turned back a generalized
appreciate just how risky that one extra partner can be if the
epidemic primarily by means of condom promotion”. Condom
relationships are long-term and concurrent. The now famously See Comment page 13,
availability remains a concern, especially in rural areas, but
successful Zero Grazing (partner reduction and faithfulness) about condoms
another serious problem is that although people worldwide,
campaign in Uganda,19,22,23,28,29 coupled with encouraging
including Africans, are likely to use condoms during casual and
evidence from other places such as Zambia,25,29 Addis Ababa,1,29
commercial sexual encounters, condoms are seldom used con-
and Kenya,23 suggests that fundamental society-wide changes in
sistently in longer-term relationships in which there is a sense of
sexual norms can occur in Africa, just as in other regions faced
www.thelancet.com Vol 364 July 3, 2004 *Daniel T Halperin, Helen Epstein
Meeting Published Abstracts, Anaheim, California, Aug 18–21, 2002: session
Office of HIV-AIDS, US Agency for International Development,
Pettifor AE, Rees, HV, Steffenson A, et al. HIV and sexual behavior among
Washington, DC 20523, USA (DTH); and Center for Health and
young South Africans: a national survey of 15–24 year olds. University of
Wellbeing, Princeton University, Princeton, New Jersey, USA (HE)
Witwatersrand, Johannesburg: Reproductive Health Research Unit, 2004:
http://www.rhru.co.za/site/publications.asp (accessed June 24, 2004).
Morris M, Kretzschmar M. Concurrent partnerships and the spread of HIV.
We thank Matina Morris, Michael Cassell, Jim Shelton, Anne Peterson, and Billy Pick
AIDS 1997; 11: 681–83.
for their input to this commentary, and Petr Petr for the graphic.
Pilcher CD, Tien HC, Eron JJ, et al. Brief but efficient: acute HIV infection and
UNAIDS. AIDS epidemic update 2003. Geneva: UNAIDS. http://www.unaids.
the sexual transmission of HIV. J Infect Dis 2004; 189: 1785–92.
org/Unaids/EN/Resources/Publications/corporate+publications/aids+
Leclerc-Madlala S. Transactional sex and the pursuit of modernity.
epidemic+update+-+december+2003.asp (accessed June 22, 2004). Social Dynamics 2003; 29: 1–21.
Eberstadt N. The future of AIDS. Foreign Affairs Nov/Dec 2002: 2–45.
Epstein H. The fidelity fix. New York Times Magazine June 13, 2004: 54–59.
World Health Organisation. Joint tuberculosis programme review, India.
Jana S, Bandyopadhyay N, Mukherjee S, Dutta N, Basu I, Saha A. STD/HIV
Doc#SEA-TB-263. New Delhi: WHO Regional Office for Southeast Asia,
intervention with sex workers in West Bengal, India. AIDS 1998; 12 (suppl B):
Chin J, Bennett A, Mills S. Primary determinants of HIV prevalence in
Ghys PD, Diallo MO, Ettiegne-Traore V, et al. Increase in condom use and
Asian-Pacific countries. AIDS 1998; 12 (suppl B): S87–91.
decline in HIV and sexually transmitted diseases among female sex workers in
Cohen J. Asia and Africa: on different trajectories? Science 2004; 304:
Abidjan, Cote d’Ivoire, 1991–1998. AIDS 2002; 16: 251–58.
Hearst N, Chen S. Condom promotion for AIDS prevention in the developing
Caldwell JC, Isaac-Toua G. AIDS in Papua New Guinea: situation in the Pacific.
world: is it working? Stud Fam Plann 2004; 35: 39–47. J Health Popul Nutr 2002; 20: 104–11.
Green EC. Rethinking AIDS prevention. Westport, Connecticut: Praeger, 2003.
Short RV. The HIV/AIDS pandemic: new ways of preventing infection in men.
Ahmed S, Lutalo T, Wawer M, et al. HIV incidence and sexually transmitted
Reprod Fertil Devel 2004; 16: 555–59.
disease prevalence associated with condom use: a population study in Rakai,
Halperin D, Bailey RC. Male circumcision and HIV infection: ten years and
Uganda. AIDS 2001; 15: 2171–79.
counting. Lancet 1999; 354: 1813–15.
Bessinger R, Akwara P, Halperin DT. Sexual behavior, HIV and fertility trends: a
Weiss HA, Quigley MA, Hayes RJ. Male circumcision and risk of HIV infection in
comparative analysis of six countries; phase I of the ABC study. Chapel Hill,
sub-Saharan Africa: a systematic review and meta-analysis. AIDS 2000; 14:
North Carolina: Measure Evaluation, 2003: http://www.cpc.unc.edu/
measure/publications/special/abc.pdf (accessed June 22, 2004).
Quinn TC, Wawer MJ, Sewankambo N, et al. Viral load and heterosexual
Meekers D, Klein M, Foyet L. Patterns of HIV risk behavior and condom use
transmission of human immunodeficiency virus type 1. N Engl J Med 2000;
among youth in Yaounde and Douala, Cameroon. AIDS Behav 2003; 7: 342: 921–29.
Caldwell JC, Caldwell P, Quiggin P. The social context of AIDS in sub-Saharan
Flood M. Lust, trust and latex: why young heterosexual men do not use
Africa. Popul Dev Rev 1989; 15: 185–234.
condoms. Culture Health Sexuality 2003; 5: 353–69.
Carael M. Sexual behaviour. In: Cleland JG, Ferry B, eds. Sexual behaviour and
Stoneburner R, Low-Beer D. Population-level HIV declines and behavioral risk
AIDS in the developing world. London: Taylor and Francis, 1995.
avoidance in Uganda. Science 2004; 304: 14–18.
Santelli JS, Brener ND, Lowry R, et al. Multiple sexual partners among
Shelton J, Halperin DT, Nantulya V, Potts M, Gayle HD, Holmes KK. Partner
U.S. adolescents and young adults. Fam Plann Perspect 1998; 30: 271–75.
reduction is crucial for balanced “ABC” approach to HIV prevention.
Morris M. A comparative study of concurrent sexual partnerships in the
BMJ 2004; 328: 891–93.
United States, Thailand and Uganda. American Sociology Association Annual
Seizing the opportunity to capitalise on the growing access to HIV treatment to expand HIV prevention
Access to antiretroviral therapy is expanding in resource-poor
current level of 5 million, treatment programmes will be un-
settings. This long-awaited action has the potential to
able to keep pace with the number of people in need, and will
improve the health of millions of HIV-infected people and
stabilise societies in regions hardest hit by HIV/AIDS. Little
However, there is a dynamic tension between the provision
discussed, however, is the fact that expanded access to
of HIV prevention and treatment. The scale-up of HIV pre-
treatment also offers critical new opportunities to simul-
vention and treatment must be carefully coordinated and
taneously strengthen HIV-prevention efforts.
integrated to ensure the maximum synergistic effect. In-
More widespread access to treatment has the potential to
creased availability of antiretroviral therapy can bolster
attract millions of people into health-care settings, in which
prevention efforts by significantly enhancing incentives for
HIV-prevention messages can be delivered and reinforced.
voluntary testing,1 reducing the stigma associated with HIV,2
The availability of HIV treatment will provide new incentives
and potentially lowering the infectivity of HIV-positive
for HIV testing, which in turn will increase opportunities for
counselling on HIV prevention. And increased knowledge of
But treatment access will also present new prevention
serostatus will enable prevention programmes to develop
challenges. As antiretroviral therapy reduces AIDS deaths in
interventions that are specifically tailored to the different
areas where treatment is available, the number of people
needs of HIV-positive, HIV-negative, and untested indi-
living with HIV will grow. As HIV-infected people on anti-
retroviral therapy become healthier, they are likely to become
To achieve a sustainable response to HIV/AIDS, prevention
more sexually active, potentially creating additional oppor-
and treatment services must be brought to scale simul-
tunities for HIV transmission to occur. Although knowledge
taneously. Unless annual HIV incidence falls sharply from its
of HIV infection prompts most people to take steps to avoid
www.thelancet.com Vol 364 July 3, 2004
ECONOMIA eFINANZA MIB 30 ULTIMA SETTIMANA DOW JONES ULTIMA SETTIMANA NASDAQ ULTIMA SETTIMANA DAX ULTIMA SETTIMANA CAC ULTIMA SETTIMANA GIORNALEdelPOPOLO VEZIA Michel Dérobert ieri al Centro studi bancari di Vezia borsa svizzera Indice SMI Baloise N Ciba Special N Cie F. Richemont Clariant N il punto critico dei bilaterali Cs Group N 4
Pronunciamiento internacional Honduras: Demandan cese a la violencia en el Bajo Aguán e investigaciones efectivas para sancionar a responsables de asesinatos Las organizaciones firmantes condenamos enérgicamente los asesinatos de 11 personas el pasado 14 y 15 de agosto de 2011 en el Valle del Bajo Aguán, Honduras, donde continúan los actos de violencia, las graves v