The Changing Face of HIV in Latin America and the Caribbean
Abstract
Latin America and the Caribbean (LAC) is a region with similarities and important disparities. In recent years LAC has witnessed achievements, with HIV prevalence rates relatively stable for LA and decreasing for the Caribbean. However average values hide differences. General population HIV prevalence in LAC is 0.4% in average. In the Caribbean there are fewer new HIV infections but HIV prevalence among adults exceeds 1% in several countries. It is estimated that 31% of adults living with HIV in LA and 52% of adults in the Caribbean are women. Unprotected sex is the main route of HIV transmission in LAC. Men who have sex with men and transgender women are the populations with the highest prevalence (10.6% and 17.7% respectively); however other key populations such as female sex workers (4.9%), drug users (range 1%-49.7% for intravenous drug users). Prisoners and indigenous populations are also important. LAC has the highest anti-retroviral treatment coverage of any low- and middle-income region in the world, but women and children are less likely than men to receive treatment. There is an important pending agenda to address the gaps in information, prevention and care for HIV in LAC.
Introduction
Latin America and the Caribbean (LAC) represent 8.3% of the world's population. The region is heterogeneous and ethnically diverse but also shares similarities. Based on those similarities, LAC can be divided into (i) Central American countries: Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama; (ii) Spanish speaking or Latin Caribbean countries: Cuba and Dominican Republic; (iii) Non-Latin Caribbean countries: Antigua and Barbuda, Bahamas, Barbados, Belize, Dominica, Grenada, Guyana, Haiti, Jamaica, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Suriname and Trinidad and Tobago; (iv) South American Southern Cone countries: Argentina, Chile, Paraguay and Uruguay; and (v) South American Andean countries: Bolivia, Colombia, Ecuador, Peru and Venezuela, which are very different (e.g. Bolivia and Ecuador have very important native indigenous populations, while in Colombia and Peru, mestizo populations predominate); (vi) Mexico; and (vii) Brazil. These last two countries are usually considered separately from the regions, due to their own large populations and land areas.
LAC countries have a higher average per capita GDP (around US$9000) than other developing regions, with 16 countries classified as middle-income and two as high-income (1). However LAC has the greatest income inequality of any region in the world (2).
The purpose of this article is to review research papers and reports from national governments and regional and international health agencies regarding HIV prevalence, incidence and trends, genotypes, key populations including women, HIV treatment and resistance, and highlights regarding prevention in the region. The goal is to illustrate the changing face of HIV in LAC and remaining challenges.
HIV in Latin America and the Caribbean
The HIV epidemic in LAC began in the early eighties and has evolved since (3). For 2012, the total estimated number of adults and children living with HIV in LAC reached 1.5 million (4), but the epidemic is not homogenous across the region (5). General population prevalence in LAC is 0.4%, based on the report of 26 LAC countries for 2012 (6). However as seen in Table 1, in the 8 Caribbean countries reporting data, 7 have prevalences over 1%, and 7 LA countries have prevalences over 0.5%. One country, Cuba, reported prevalence under 0.1%. Worldwide the Caribbean is the region with the second highest prevalence after sub-Saharan Africa(6).
Table 1
| Country | Adult HIV prevalence (%) (2013) | Ratio of men / women living with HIV (2012)6 | % of pregnant women tested for HIV and received results (2010-11)13 | HIV prevalence (%) among pregnant women (2010-11)13 | % of HIV- positive pregnant women who receive ARTs (2011)13 | Vertical HIV transmission rate % (2012)13 | % infants born to HIV-positive women on prophylaxis (2010-11)13 |
|---|---|---|---|---|---|---|---|
| Andean | |||||||
| Bolivia | 0.3 | 2.3 | 61% | 0.12 | 52% | 21.7% | 79% |
| Colombia | 0.5 | 2.3 | 61% | 0.13 | 49% | 17.4% | 14% |
| Ecuador | 0.6 | 3.3 | 94% | 0.24 | 4.4% | 56% | |
| Peru | 0.4 | 2.1 | 78% | 0.23 | 56% | 3.9% | NR |
| Venezuela | 0.6 | 1.6 | NR | NR | 34% | 25.5% | 6-12% |
| Brazil | 0.5 | 2.3 | 79% | 0.41 | 50% | 6.8% | 87% |
| Central America | |||||||
| Costa Rica | 0.3 | 1.4 | 84% | 0.04 | 71% | 2.9% | 19% |
| El Salvador | 0.6 | 1.7 | 67% | 0.09 | 69% | 6.9% | 8-50% |
| Guatemala | 0.7 | 1.7 | 30% | 0.25 | 16% | 31.0% | 6% |
| Honduras | 0.5 | 1.5 | 62% | 0.50 | 45% | 22.0% | 34-82% |
| Nicaragua | 0.3 | 2.3 | 87% | 0.03 | 94% | 4.4% | 20% |
| Panama | 0.7 | 2.2 | >95% | 0.30 | 71% | 0.5% | 69% |
| Latin Caribbean | |||||||
| Cuba | 0.0 | 3.7 | >95% | 0.03 | 99% | 1.1% | >95% |
| Dominican Republic | 0.7 | 0.9 | 46% | 0.83 | 81% | 10.0% | 64% |
| Mexico | 0.2 | 3.5 | 37% | 0.03 | 43% | 12.9% | 4-15% |
| Non-Latin Caribbean | |||||||
| Antigua & Barbuda | NR | NR | 55% | 1.50 | NR | 20.0% | NR |
| Bahamas | 3.3 | 1.0 | 73% | 0.88 | 88% | 5.0-7.0% | NR |
| Barbados | 0.9 | 2.0 | 63% | 0.22 | 96% | 0.0% | NR |
| Belize | 1.4 | 0.9 | 87% | 0.86 | 100% | 6.6% | 54% |
| Dominica | NR | NR | 64% | 0.30 | 100% | 0.0% | NR |
| Grenada | NR | NR | >95% | 0.06 | NR | 0.0% | NR |
| Guyana | 1.3 | 0.9 | >95% | 0.88 | 65% | 4.6% | >95% |
| Haiti | 2.1 | 0.7 | 51% | 2.50 | 78% | 11.1% | 31% |
| Jamaica | 1.7 | 2.0 | 55% | 0.93 | 57% | 7.6% | 69% |
| St. Kitts & Nevis | NR | NR | 56% | 0.17 | 100% | 0.0% | 100% |
| St. Lucia | NR | NR | 65% | 0.24 | 80% | 0.0% | NR |
| St. Vincent&Grenadines | NR | NR | >95% | 0.70 | 89% | 6.7% | NR |
| Suriname | 1.1 | 0.9 | 85% | 0.70 | NR | 5.5% | >95% |
| Trinidad and Tobago | 1.6 | 0.9 | 70% | 1.36 | 82% | 14.9% | NR |
| Southern Cone | |||||||
| Argentina | 0.4 | 2.0 | >95% | 0.44 | 83% | 4.4% | >95% |
| Chile | 0.4 | 6.2 | 82% | 0.14 | 72% | 5.1% | NR |
| Paraguay | 0.3 | 1.4 | 48% | 0.34 | 43% | 15.5% | 52% |
| Uruguay | 0.7 | 3.8 | 72% | 0.03 | 84% | 2.6% | 23% |
NR=NR
Trends on HIV prevalence and incidence in LAC
As shown in Figure 1, data on HIV adult prevalence and incidence from the 2013 UNAIDS report (6) show interesting trends in LAC. From 1990 through 2012 there have been only slight variations in HIV prevalences in the Andean and Southern cone countries, Brazil and Mexico. By contrast, the prevalences for the Latin Caribbean, and moreso the Non-Latin Caribbean countries peaked above 1% in the same two decade period, indicating generalized epidemics, that are fortunately receding in both sub-regions. The behavior of the epidemic in Central American countries is more erratic, with peaks in 1992 and 2000, the first of which is probably an artifact of variations in the completeness of the data collected. In general, sub-regions that reached the highest levels fortunately show important declines, while the other sub-regions have reached a steady state.
Incidence data are harder to obtain, and in many cases incidence estimates have not been properly adjusted (7)(8). The 2013 UNAIDS report showed that from 1990 to 2012 there was a dramatic sustained drop in annual incidence in the Latin and Non-Latin Caribbean countries (Figure 1). Annual incidence rates in Mexico have always been low, but also showed a decline. In the Andean countries, incidence peaked at 53 cases per 100,000 population in 2006, but then dropped to less than 20 cases after 2000, leveling off after 2005. To a large degree then, incidence figures are encouraging in all sub-regions with data available. The report did not include incidence data for Brazil or Southern cone countries.
HIV genotypes in LAC
HIV-1 subtype B has been the predominant form circulating in LAC, followed by subtypes C, F, and A. The BF circulating recombinant form (CRF) has been found in Brazil, Uruguay and Argentina (9)(10)(11).
Women Living with HIV in LAC
An estimated 31% of adults living with HIV in LA and 52% of adults in the Caribbean are women (6). The ratio of men to women living with HIV varies by country but on average in LA more men than women have HIV, ranging from 1.4 in Paraguay to 6.2 in Chile (Table 1). On the other hand in most Non-Latin Caribbean countries, more women than men are HIV positive. Women's vulnerability to HIV is influenced by diverse contextual factors – including physical, social, economic, and policy-related – operating at multiple levels and affects women from different ages and at different situations (12). However, most studies and efforts with women in the LAC region have been focused on pregnant women and sex workers.
Table 1 presents national statistics as reported to the Pan American Health Organization and the United Nations. HIV testing among pregnant women has increased greatly from 2005 to 2011, from 29% to 66% in LA and 24% to 61% in the Caribbean. However, the proportion of pregnant women who were tested for HIV and received their results varies greatly by country. In Guatemala and Mexico, only 30% and 37% of pregnant women, respectively, were tested. Coverage stood at less than 50% in the Dominican Republic and Paraguay and at 70% or less in several Central American, Andean and Non-Latin Caribbean countries (13).
Independent research studies show disparities in HIV testing by pregnant women's characteristics. In El Salvador, a national representative sample of 2,929 pregnant women showed that HIV testing was higher among women with more education, higher income, more antenatal care visits and living in areas with lower HIV incidence (14). Another study in Colombia showed that women with subsidized insurance for poor citizens had lower odds (OR=0.82) of being tested for HIV(15).
HIV prevalence among pregnant women in most countries in LAC is 0.5% or less, except for those in the non-Latin Caribbean region, with prevalences as high as 2.5% reported in Haiti (13). However there has been a decline of HIV prevalence among pregnant women in this country (16)(17).
Prevention of Mother-to-Child Transmission (MTCT) of HIV
Antiretroviral coverage among pregnant women increased from 2005 to 2011 from 42% to 67% of pregnant women in LA and from 14% to 79% of pregnant women in the Caribbean (13). Antiretroviral coverage varies by country. As seen in Table 1, coverage is lowest in Guatemala (16%) and Venezuela (34%) and Belize, Dominica and St. Kitts and Nevis report coverage at 100%.
The MTCT rate for LAC decreased from 18.6% (10.5-22.9%) in 2010 to 14.2% (5.8-18.5%) in 2011 (13). Several countries reported reaching the regional target of vertical transmission rate under 2%, including Barbados, Dominica, Grenada, St. Kitts and Nevis and St. Lucia (all 0.0%), Panama (0.5%) and Cuba (1.1%). Argentina, Costa Rica and Nicaragua were close to the target (rates of 2-5%). However many countries remain with very high vertical transmission rates with the higher levels for Bolivia (21.7%), Venezuela (25.5%) and Guatemala (31.0%)(13).
Finally, the proportion of infants born to HIV-positive women receiving prophylaxis to prevent MTCT (Table 1) and receiving virological testing within two months of birth varies also greatly by country(13).
HIV infection in Children and Youth in LAC
The number of children acquiring HIV infection declined in both the Caribbean, by 32%, and LA by 24%, from 2009-2011(13).
There is limited information about young people living with HIV in LAC. Prevalence among 15-24 year olds was estimated at 0.3% or less among most males and females throughout LA. Estimates are lacking for six Caribbean countries. In others, prevalence among 15-24 year olds was estimated to be 0.5% or less in Cuba, Barbados, Dominican Republic and among males in Guyana and females in Jamaica. In other Caribbean countries, prevalence among youth stood at 0.6-0.9%, with the exception of Bahamas, with an estimated prevalence of 1.3% among male and 1.8% among female youth (6).
One study analyzed the characteristics of 12-21 year olds from a prospective cohort study of HIV-infected youth at 15 sites in Brazil, Argentina and Mexico. Sixty-nine (58%) participants acquired HIV through vertical transmission and 51(42%) through horizontal transmission. In the latter group, 33 (65%) were through sexual transmission, 10 (20%) through blood transfusions and 8 (15%) through unknown causes (18). In Haiti, a study on risk factors for HIV in adolescents and young adults attending a clinic for voluntary counseling and testing, showed a prevalence of 6.3% 2533 females and 5.5% of 858 males (19).
HIV in Key Populations
a. Men Who Have Sex with Men (MSM) and Transwomen (TW)
Recent reviews demonstrate that MSM and TW are at very high risk for HIV infection globally (20)(21) and in LAC (22). The global review of MSM found pooled HIV prevalence of 14.9% (95% CI: 14.1-15.7) for Central and South America and 25.4% (95% CI: 21.4-29.5) for Caribbean, with the latter representing the highest pooled estimate of any region (20). The global review of transwomen found a pooled HIV prevalence of 17.7% (95% CI: 15.6-19.8) for 10 low- and middle-income countries, including 5 Latin American countries (21). The regional review found a median HIV prevalence of 10.6% among MSM in LAC (22).
Recent studies with MSM in LAC have used different sampling methods and most have used respondent-driven sampling (RDS), as shown in a review of RDS-based HIV surveillance among MSM and other key populations in LAC (23). Other recent studies have included data on transwomen. (See Table 2)
Table 2
| Country, City | Year | Sampling method | N tested for HIV | HIV prevalence in MSM and TW (%, 95% CI) | HIV prevalence in only TW (%, 95% CI) | Country, City (c if capital) | Year | Sampling method | N tested for HIV | HIV prevalence in MSM and TW (%, 95% CI) | HIV prevalence in only TW (%, 95% CI) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Andean | Nicaragua33 | ||||||||||
| Bolivia21 | Managua | 2009 | RDS | 639 | 7.5, 4.5-11.1 | 18.8, 2.5-38.6 | |||||
| Santa Cruz | 2008 | RDS | 361 | 15.3, 9.9-21.8 | NR | Chinandega | 2009 | RDS | 313 | 3.1, 1.2-6.3 | 14.6, 3.4-55.0 |
| Cochabamba | 2008 | RDS | 232 | 10.2, 6.1-18.1 | NR | Panama 34 | 2011 | NR | 800 | 22.8, NR | NR |
| La Paz / El Alto | 2008 | RDS | 203 | 9.6, 0.0-26.2 | NR | Latin Caribbean | |||||
| Colombia22 | Cuba 36 | ||||||||||
| Bogotá | 2010 | RDS | 485 | 15.0, 10.9-19.9 | NR | La Habana | 2010 | Conven | 484 | 7.4, NR | NR |
| Cali | 2010 | RDS | 333 | 24.1, 18.1-30.4 | NR | Dominican Republic38 | |||||
| 5 other cities | 2010 | RDS | 1,744 | Range 5.6 to 13.6 | NR | Santo Domingo | 2008 | RDS | 510 | 5.9, 3.2-9.0 | NR |
| Ecuador | Barahona | 2008 | RDS | 281 | 5.7, 1.5-10.5 | NR | |||||
| Quito23 | 2010-11 | RDS | 414 | 11.0, 7.3-15.5 | NR | La Alta Gracia | 2008 | RDS | 270 | 7.6, 4.1-12.0 | NR |
| Peru | Santiago | 2008 | RDS | 327 | 5.1, 2.3-8.7 | NR | |||||
| Lima/Callao24 | 2011 | Conven | 2,959 | 12.4, 11.2-13.6 | 20.8, 17.2-24.3 | Mexico | |||||
| Lima/Callao25 | 2009 | RDS | 439 | 29.6, 22.6-38.7 | 24 cities44 | 2011 | Probabil | 6,723 | 16.9, 15.6-18.4 | NR | |
| Brazil27 | 2009 | RDS | 3,384 | 11.1, 9.1-13.6 | TNI | Non-Latin Caribbean | |||||
| Rio de Janeiro | 2009 | RDS | NR | 16.5, 9.3-22.8 | TNI | Bahamas 35 | 2012 | Conven | 36 | 14.0, NR | NR |
| 9 other cities | 2009 | RDS | NR | Range 1.7 to 10.2 | TNI | Dominica37 | NR | Conven | NR | 26.7, NR | NR |
| Central America | Guyana 39 | 2009 | NR | 108 | 19.4, NR | NR | |||||
| Costa Rica28 | Haiti 40 | 2011 | RDS | 860 | 13.4, 11.1-17.2 | NR | |||||
| San José | 2009 | RDS | 300 | 10.9, 5.3-18.3 | NR | Jamaica 43 | 2011 | NR | NR | 32.8, NR | NR |
| El Salvador29, 30 | St. Vincent and the Grenadines41 | 2010 | Conven | 75 | 29.5, NR | NR | |||||
| San Salvador | 2008 | RDS | 516 | 10.8, 7.4-14.7 | 19.7, 5.4-39.4 | Suriname 42 | 2004 | NR | NR | 6.7, NR | NR |
| San Miguel | 2008 | RDS | 183 | 8.8, 4.2-14.5 | 23.3, 6.3-47.6 | Southern Cone | |||||
| Guatemala31 | Argentina45 | ||||||||||
| Guatemala City | 2012-13 | RDS | 435 | 8.9, 5.4-13.2 | NR | Buenos Aires | 2007-09 | RDS | 296 | 17.3, 14.0-20.8 | TNI |
| Coatepeque | 2012-13 | RDS | 106 | 2.8, 0.6-8.0 | NR | Chile46 | |||||
| National | 2012-13 | RDS | 126 | 23.8, 16.7-32.2 | Santiago / Valparaíso | 2008-09 | RDS | 469 | 21.1, 12.8-30.0 | NR | |
| Honduras32 | Paraguay47 | ||||||||||
| Tegucigalpa | 2006 | RDS | 193 | 5.7, NR | NR | Ciudad del Este | 2006 | RDS | 296 | 0.5, 0.0-1.2 | NR |
| San Pedro Sula | 2006 | RDS | 204 | 9.7, 4.6-15.2 | NR | Uruguay48 | 2008 | NR | 309 | 9.0, NR | NR |
| La Ceiba | 2006 | RDS | (est. 167) | 4.8, 1.4-8.6 | NR |
NR = not reported; TNI: Transwomen not included; RDS=respondent-driven sampling; Conven=Convenience sample; Probabil=Probability sample
Studies in the Andean Region found HIV prevalences ranging from 5.6% to 15.3% among MSM (24)(25)(26)(27). HIV prevalence in Cali, Colombia was higher, at 24.1% (25). Colombia and Peru had very large samples and Peru's sample included a high proportion of transwomen (17.8%). Peruvian transwomen had a higher HIV prevalence (20.8%) than the overall sample (12.4%) of MSM and transwomen (27). Two research studies in Lima, Peru warrant mention. An RDS study with only transwomen (n=439) found anestimated HIV prevalence of 29.6% (28). A small study that compare 89 Cercado (downtown) and non-Cercado (close urban) MSM sex workers. found much higher HIV prevalence among the Cercado (23%) versus non-Cercado sex workers (4%) (29). No data are available for Venezuela.
In 2009, Brazil carried out its first national biological and behavioral HIV surveillance survey among MSM. The study used RDS to sample 3,859 MSM across 10 cities. Overall HIV prevalence among those tested was 11.1%. HIV prevalence was highest in Rio de Janeiro (16.5%) but transwomen were not included in the survey (30).
Most recent studies in Central America have used RDS and reported HIV prevalences ranging from 2.8% to 10.9%. Central America is a leader in the region for considering transwomen as a unique population. In all studies except the one in Panama, the proportion of transwomen included ranged from 5.4% to 27.9% of the sample or testing pool. HIV prevalences among transwomen ranged from 14.6% to 23.8% (31)(32)(33)(34)(35)(36)(37)
High-quality data on HIV prevalence among MSM in the Caribbean is highly limited, with the exception of the Dominican Republic. Many studies used convenience sampling with very small or biased samples and most provided little information about the methodologies employed or samples included. Nevertheless, these studies represent an important step forward in countries that previously had no previous data about HIV prevalence among MSM, particularly considering that several countries found very high prevalences (38)(39)(40)(41)(42)(43)(44)(45). Jamaica reported the highest HIV prevalence among MSM (32.8%) of any country in the entire LAC region(46).
Mexico carried out the largest recent study in LAC, with 6,723 MSM from 24 cities. After mapping MSM gathering points in each city, the study used a two-stage probabilistic design to select cities and gathering points in each city. Overall HIV prevalence was 16.9%, ranging from 9.9% in central west to 20.4% in central east Mexico. The study did not analyze transwomen separately (47).
Regarding the Southern Cone countries, studies from Argentina, Chile and Paraguay that used RDS with MSM, with no separate analyses for transwomen. The HIV prevalence was 17.3% in Buenos Aires, 21.1% in Santiago/Valparaíso, and a very low 0.5% in Ciudad del Este, in the Paraguayan triple-border area with Brazil and Argentina. (48)(49)(50)(51).
One of the remaining significant challenge in the region, having recognized the magnitude of the epidemic among MSM and transwomen, is to focus enough resources on prevention and treatment within these groups. A study evaluating resource allocation for HIV, demonstrated that in the 23 countries reporting data, 75% of expenses go to treatment and care while only 15% go to prevention. Moreover, of the 12 countries reporting investments in prevention, only Peru reported more than 5% of HIV prevention funding directed towards MSM prevention activities (52). The funding mismatch regarding treatment and prevention and regarding appropriate targeting of prevention activities to those key populations with the highest vulnerabilities needs to be resolved.
b. HIV and Prisons in LAC
Early during the HIV/AIDS epidemic, prisons were recognized as areas where HIV transmission could happen more often due to overcrowding, violence, lack of information about HIV, and the presence of people infected prior to imprisonment. Frequent, although not always “accepted,” practices such as drug use, same sex intercourse or commercial sex increase the risk of HIV acquisition or transmission among these confined individuals (53). However data relevant to these populations are limited (54). One global review regarding HIV in prisons showed that prevalences could be as high as 37.5% (55). Three LA countries reported very high prevalences: Argentina (37.5%); Cuba (25.8%); and Brazil (from 3.4% to 17.4% in Rio de Janeiro). Most of the data came from conference abstracts, from specific cities or institutions, and from the 1990s. A review of articles published in scielo (www.scielo.org) showed more recent data. In prisons in Peru, there was a prevalence of 1.1% for men in one of the largest prisons in the country (56) and 2.2% for women, the latter with very high prevalences of other sexually transmitted diseases (57). Studies in other countries showed higher HIV prevalences among male prisoners: Belize with 4.0% (58), Uruguay with 6.5% (59), and Venezuela with 4.0% (60).
There are very few studies regarding prevention or challenges of antiretroviral treatment among prisoners. One recent study from Brazil demonstrated a high proportion of virologic failure among inmates under treatment, with low adherence to ARV and high proportion of primary and secondary resistance (61). There is a need to have more and better information to guide prevention and treatment and care strategies in prisons in LAC, particularly considering the risks, high morbidity and the potential of transmission of HIV and resistance within and outside such facilities.
c. Female sex workers (FSW)
Commercial sex varies across the world but has been identified as one of the key practices driving the HIV pandemic (62). HIV infection among FSWs varies by geographical epidemic typology, structural factors (power dynamics, violence, stigma, policies) and overlapping risk behaviors such as injection drug use and condom use (63).
Despite the fact that FSW have lower reported HIV prevalences than MSM, they represent a key population for transmission of HIV and other STIs and for prevention activities in LAC due to the high percentage of men visiting FSWs on average 5-7% of men in the region (64).
Although data characterizing HIV risk among FSWs are scarce, the burden of disease is high overall and even higher in non-Latin Caribbean countries. A recent meta-analysis of HIV infection in FSW, included data from 9 countries in LA and two from the non-Latin Caribbean region (65). The estimated HIV prevalence among FSWs in LA countries was 4.9%, with values ranging from 0% in Chile to 9.7% in Honduras. HIV prevalence among FSWs was higher in the Caribbean, 8.8% in Jamaica, and 27.6% in Guyana, as confirmed in a recent UNAIDS report (66). Another interesting observation was that the estimated odds ratio for HIV infection among FSWs vs general population females for LAC was 12.0, high but still lower than for Africa or Asia (65).
In a comprehensive national survey from Peru, HIV prevalence among FSWs was estimated at 0.5%, versus 0.1% for general population females, with an excess odds of 5.0 (67). Promotion of protective sexual practices including access to HIV/STI prevention services and testing might be higher among FSW than among women in the general population. In the case of Peru, the National HIV/STI Program began implementing HIV/STI prevention activities and services to FSWs very early in the epidemic, which may explain the low HIV prevalence in this population (68). In Honduras a prevention intervention with FSWs in 3 cities maintained HIV were associated with HIV prevalences at about 0.44% among FSWs. (69)
A survey of 19 Latin American countries regarding organizational aspects of HIV/STI National programs showed that regular HIV screening (together with syphilis screening) is almost universal in the region for FSWs (16/19 countries). Availability of regular HIV screening for other key populations is much lower: pregnant women (8/19); men who have sex with men (4/19); and prisoners (1/19) (70). The early recognition of a need and implementation of services for FSWs as an HIV prevention strategy in several countries in LAC region could explain the relatively low levels of HIV infection in this population compare with MSM, and highlights the importance of such services. However it is clear that there is a great variability between and within countries, including for example differences within the same city by type of commercial sex venue.
There is a need to further study the legal and policy environments in which sex workers operate and the effects of interventions in this area e.g. “registration” of FSWs (71)(72). There is evidence of the positive effect of prevention interventions which suggests the need to continue, scale up and strengthen HIV prevention programs directed to FSWs in LAC.
d. Drug users
According to a study published by the United Nations Office for Drug and Crime (UNODC) (73), the use of illegal drugs in LAC is 4.8%, higher than the global average of 3.8%. However the region has certain peculiarities. Marijuana and cocaine are the most common used, after alcohol. Injected drugs are mainly used in the Southern Cone, Brazil and in Caribbean countries (74). In Andean countries like Bolivia, Colombia, Ecuador and Peru smoking cocaine base paste is more popular (75).
HIV is associated with intravenous drug use (IDU) in certain parts of LAC (76). However data on this issue is scarce. According to a recent systematic review, in the Caribbean data are only available for Puerto Rico (HIV prevalence 12.9% in IDU) and for Latin America, only for Argentina, Brazil and Colombia with prevalences of 49.7%, 48% and 1.0% respectively (77). In Puerto Rico, IDU accounted for 40% or men and 26% of women newly infected with HIV in 2006 (78). In Mexico, a mixture of commercial sex and IDU has been documented as an important driver of the epidemic, especially along the US-Mexico border (79)(80)(81). Crack cocaine users appear to be another affected population in the region due to risky behaviors as unsafe sex and commercial sex in order to support their drug use habits (82). Finally, and given the high prevalence of alcohol use region-wide, a recent study explored alcohol use among 5,148 men who have sex with men in Peru. The study found that 62.8% had at least one alcohol use disorder and that having a disorder was associated with higher HIV risk-taking behavior (83)
e. Indigenous populations
HIV among indigenous populations is an emerging public health concern (84). These populations have socioeconomic and health disadvantages. Although they account for 4.5% of the total global population, they represent 10% of the global poor (85). In LAC, 512 indigenous populations have been identified. Brazil has the higher number of groups, but approximately 87% of all indigenous population live in Bolivia, Colombia, Guatemala, Mexico and Peru (86). Nonetheless, HIV data on indigenous populations in Latin America are scarce. In Peru, a seroprevalence study in 2004 found a very high HIV prevalence of 7.5% and 6.3% among two Chayahuita communities, associated with male to male sex and returning migrants to the community (87). In a more recent study from Peru, HIV prevalence was 0.16% and 0.29% for women and men, respectively, for 6 Amazon Basin communities (88). In two other remote Peruvian communities, HIV prevalence was 0.0% for women and 0.7% for men, with both HIV positive cases among men who reported sex with other men (89).
In Brazil, a study with indigenous populations from the Amazon found an HIV prevalence of 0.1% (90). In Honduras, a study with Garifuna Indians found a prevalence of 4.5% (91). In Venezuela, a study with the Warao Amerindians found a very high prevalence of 15.6% for men and 2.6% for women (92). In Paraguay a study on indigenous women from different ethnic groups showed a prevalence of 0.6% (93).
As shown, although data varies according the group studied, HIV is already affecting indigenous populations. Overall, prevalence remains low, but is associated with risk factors such as same sex intercourse among men and migration. Some of these indigenous groups are nearing extinction and the promotion of condom use is not popular since they are trying to have more children. Therefore, there is an urgent need to monitor trends but more importantly to develop culturally appropriate sexual health programs and prevention strategies targeted specifically to these population.
Antiretroviral therapy (ART) in LAC
LAC initiated the introduction of ART relatively early. Brazil and Argentina took the lead in the implementation of ART free access programs in 1991-1992, together with laboratory systems for monitoring (94). Impressive progress has been seen in the last years, with ART treatment coverage increasing from 64% to 80% in Latin America and 45% to 70% in the Caribbean between 2009 and 2012 (6). Universal access to treatment has been achieved in Brazil, Costa Rica and Mexico (95). Funding for ART in LAC is mainly through domestic resources (52). The scale up of treatment in the region has been achieved due to decentralization, community programs, price negotiations, and expanding local production and distribution of ART drugs (95). Increase access to ARV has resulted in decrease mortality due to HIV/AIDS in the region at at least 50% between 2001 and 2010 (96).
Since ART implementation in LAC began more than a decade ago, concerns about the emergence and spread of drug resistance strains have arisen. Since most patients in LAC started directly with HAART instead of mono or biotherapies like in the US or Europe, initially concerns were lower. Nevertheless, other issues such as low adherence, stockouts or the lack of second-line therapies could promote emergence or resistance and then spread to new HIV infections. A recent review on ART resistance in LAC highlighted differences within the region and showed that most countries have reached WHO threshold of 5% of resistance, with a regional average of 7.7% resistance strains. This underscores the need to monitor resistance in the region (97).
There are important gaps related to ART coverage in LAC. For example estimated ART coverage is higher among men (64%) than women (56%) for the Caribbean countries (76). Coverage for key populations is estimated to be much lower due to lack of knowledge, fear to discrimination and poor access to overall health and HIV-related services. One study on the treatment cascade in LAC comes from Brazil and showed that people are lost at various stages during ART, reducing significantly the proportion reaching viral load suppression (6).
Conclusions
The face of HIV is changing in LAC, with overall trends indicating a positive evolution with declining prevalences. However disparities and challenges remain. There is an important pending agenda to (1) improve monitoring of the epidemic, especially among key populations, such as MSM; (2) resolve the funding mismatch between treatment and prevention; and (3) target prevention and treatment services to key populations while assuring continuity and monitoring of care.
Footnotes
Compliance with Ethics Guidelines: Conflict of Interest: Patricia J. García, Angela Bayer, and César P. Cárcamo declare that they have no conflict of interest
Human and Animal Rights and Informed Consent: This article does not contain any studies with human or animal subjects performed by any of the authors.