Exploring Migratory Dynamics on HIV Transmission: The Case of Mexicans in New York City and Puebla, Mexico

Abstract

Migration and population movement are increasingly viewed as important factors associated with HIV transmission risk. With growing awareness of the potential impact of migration on HIV transmission, several perspectives have emerged that posit differing dynamics of risk. We considered available data on the role of migration on HIV transmission among Mexican migrants in New York City and Puebla, Mexico. Specifically, we examined 3 distinct models of migratory dynamics of HIV transmission—namely, the structural model, the local contextual model, and the interplay model. In doing so, we reframed current public health perspectives on the role of migration on HIV transmission.

The epidemiological literature related to Latinos and HIV in the United States highlights geographic disparities in disease burden.¹ HIV/AIDS cases among Latinos are clustered geographically, such that Latinos experience increased vulnerability as a function of residence in high-risk physical and geographic areas.² Recent trends in HIV infection demonstrate that Latino mobility and migratory patterns are potentially associated with increased HIV incidence.³ As a result, several key dynamics to account for the role of migration and HIV transmission have emerged in recent literature. However, to adequately address the current HIV epidemic among Latinos, greater consideration of each of these mechanisms and enhanced attention to the role of geography and migration is warranted.⁴ Recent findings increasingly draw attention to the role of population mixing and movement, geography, and other physical spaces as important factors for understanding Latino HIV disparities.⁵ We build upon this work by examining the available empirical literature on HIV and migration in relation to the social structures and contexts in which risk behavior takes place. Specifically, we explored 3 mechanisms for the impact of migration on HIV transmission through the case of Mexican migrants in New York City (NYC) and Puebla.

As the epicenter of the HIV/AIDS epidemic in the United States, NYC is one such high-risk geographic area.⁶ New York City has an incidence rate 3 times the national average and the highest number of AIDS cases relative to any other metropolitan city.⁶ Latinos in the city are disproportionately affected by the disease and are twice as likely to be diagnosed with HIV/AIDS compared with non-Hispanic Whites.⁷ Furthermore, although Latinos account for approximately 25% of the population in NYC, they represent 33% of NYC persons living with HIV/AIDS (PLWHA).^8,9 Among NYC Latinos, HIV occurs primarily among adults through high-risk sexual behavior and intravenous drug use.¹⁰ Specifically, Latino men who have sex with men (MSM) constitute the majority of cases (40%), followed by injection drug users (27%).¹⁰ These data suggest that in NYC, Latino MSM and intravenous drug users bear the burden of HIV disease. However, a significant proportion of Latina women in NYC infected with HIV are exposed through high-risk sexual activity (67%) and represents a steady proportion of new HIV diagnoses among women in recent years.¹¹

HIV/AIDS is of particular concern among Latinos as they are more likely to experience delays in access to care, which results in adverse health outcomes. For example, Latinos, particularly Mexicans with low levels of acculturation, are less likely to obtain an HIV test.¹² Those who are diagnosed often experience rapid progression to AIDS, suggesting that many Latinos are diagnosed late in their infection.⁶ In 2011, for example, 31% of Latinos diagnosed with HIV in NYC were concurrently diagnosed with AIDS, compared with only 15% of Whites.¹¹ Late diagnosis puts Latinos at greater health risks because they do not receive the benefits of early antiretroviral treatment.¹³ In addition to late diagnosis and delayed treatment, obstacles in access to HIV treatment for Latinos include lack of a designated routine health care provider and adequate health insurance.¹⁴

Increasingly, the Latino population in NYC has undergone important demographic changes.¹⁵ Specifically, migratory changes have shifted the composition of the Latino population in NYC, introducing new Latino subgroups to a geographic area of heightened HIV risk. Traditionally, the Latino population in NYC has been classified as largely stemming from the Caribbean—specifically, Puerto Rico and the Dominican Republic. However, Mexicans, whose US migration patterns have traditionally been associated with the areas of the Southwest, are increasingly moving to NYC, a nontraditional receiving community.

For example, the Mexican population in NYC in 2010 was more than 5 times what it was in 1990.¹⁶ In 1990, an estimated 56 700 Mexicans were living in NYC; by 2000, this number grew to 180 000, and later to 325 000 in 2010.¹⁶ Foreign-born males with less than a high-school education represent the bulk of the Mexican population growth and a significant portion of this population attains employment in NYC.¹⁵ By 2024, it is predicted that Mexicans will be the most populous Latino ethnic subgroup in the largest city of the United States.¹⁷ One notable feature of NYC’s Mexican community is that nearly half (45%) originates from the state of Puebla in east-central Mexico, although other sources suggest far higher proportions (more than 70%).¹⁸ Data from the American Community Survey demonstrate that Mexican-born persons are geographically clustered in specific target communities, predominantly the Bronx and Queens (Figure 1).¹⁹

FIGURE 1—

Foreign-born from Mexico by Public Use Microdata Areas in New York City: 2006–2008.

Note. PUMA = Public Use Microdata Area.

Source. US Census Bureau.²⁰

HIV/AIDS AMONG MEXICANS IN NEW YORK CITY

In general, research related to Mexicans in NYC has not adequately documented HIV disease burden or described transmission dynamics.²¹ Despite the overall lack of attention to Mexican immigrants and HIV transmission in NYC, several key data sources exist. These data serve as the basis for growing recognition that Mexican immigrants are a population at risk of acquiring HIV and in need of greater research and applied public health attention.^4,22 For example, NYC Mexicans have the second-highest rate of new HIV diagnoses among any foreign-born group living in NYC, accounting for more than one third of all new cases.²³ According to data collected by the NYC Department of Health and Mental Hygiene (DOHMH), there were approximately 1200 Mexican-born PLWHA in 2009.²³ Foreign-born Mexican individuals constitute about 1% of NYC’s total PLWHA, with the majority living in the boroughs of Queens (33%) and Manhattan (25%).²³ The largest number of foreign-born Mexican PLWHA (22%) in 2009 lived in West Queens (Table 1).²³

TABLE 1—

Mexican-Born Persons Diagnosed With HIV/AIDS Reported in New York City and Presumed to Be Living With HIV/AIDS as of December 31, 2009

UHF Neighborhood	No. (%)
Bayside - Little Neck	1 (0.1)
Bedford Stuyvesant - Crown Heights	11 (0.9)
Bensonhurst - Bay Ridge	10 (0.8)
Borough Park	30 (2.5)
Canarsie - Flatlands	2 (0.2)
Central Harlem - Morningside Heights	21 (1.8)
Chelsea - Clinton	56 (4.7)
Coney Island - Sheepshead Bay	25 (2.1)
Crotona - Tremont	21 (1.8)
Downtown - Heights - Park Slope	25 (2.1)
East Flatbush - Flatbush	20 (1.7)
East Harlem	49 (4.1)
East New York	9 (0.8)
Flushing - Clearview	8 (0.7)
Fordham - Bronx Park	61 (5.2)
Fresh Meadows	2 (0.2)
Gramercy Park - Murray Hill	22 (1.9)
Greenpoint	17 (1.4)
Greenwich Village - Soho	16 (1.4)
High Bridge - Morrisania	37 (3.1)
Hunts Point - Mott Haven	40 (3.4)
Jamaica	13 (1.1)
Kingsbridge - Riverdale	5 (0.4)
Long Island City - Astoria	48 (4.1)
Lower Manhattan	3 (0.3)
Northeast Bronx	3 (0.3)
Pelham - Throgs Neck	27 (2.3)
Port Richmond	9 (0.8)
Ridgewood - Forest Hills	19 (1.6)
Southeast Queens	2 (0.2)
Southwest Queens	12 (1.0)
Stapleton - St George	10 (0.8)
Sunset Park	49 (4.1)
UHF or borough unknown	43 (3.6)
Union Square - Lower East Side	25 (2.1)
Upper East Side	11 (0.9)
Upper West Side	31 (2.6)
Washington Heights - Inwood	43 (3.6)
West Queens	263 (22.3)
Williamsburg - Bushwick	36 (3.0)

Note. UHF = United Hospital Fund.

Source. HIV Epidemiology and Field Services Program.²³

HIV among Mexican PLWHA is primarily transmitted through sexual contact. Specifically, more than half (53%) of foreign-born HIV-infected individuals were classified as MSM, approximately one fifth (19%) were classified as heterosexual contact, 6% were injection drug users, and 22% were classified as having an unknown method of transmission.²³ These data suggest that sexual behavior is the primary mechanism through which Mexican immigrants acquire HIV. However, important to note is the large percentage of Mexican PLWHA whose HIV acquisition is classified as “unknown.”

Epidemiological surveillance of HIV/AIDS among Mexican immigrants in NYC is difficult. Oftentimes, Mexican immigrants are largely hidden from the public health reporting infrastructure and lack documentation to routinely access points of care.²⁴ For example, the NYC DOHMH noted that Mexican-born PLWHA may be undercounted and that their disease burden and health needs are largely unknown.²³ Despite the paucity of available information to best inform the public health response to the health needs of Mexican immigrants, what is well established is that most Mexicans in NYC are geographically linked. Specifically, most Mexican immigrants in NYC originate from Puebla and reside in specific NYC high-risk HIV/AIDS communities. This migration pattern is novel and provides an opportunity for both research and programmatic efforts.

HIV/AIDS AMONG MEXICANS IN PUEBLA, MEXICO

HIV/AIDS in Mexico has significantly increased in recent years. The state of Puebla in east-central Mexico currently represents the fifth highest percentage of total HIV cases in Mexico today.²⁵ According to Mexico's National Center for the Prevention and Control of HIV/AIDS, Puebla’s HIV incidence rate was 118.1 per 100 000 in 2010, slightly below the national average of 133.²⁶ Most HIV cases in Puebla occur among those between the ages of 25 and 44 years (67%), and the majority of HIV-infected persons are male (77%).²⁷ HIV-infected males in Puebla are most likely to acquire HIV through heterosexual (40%) or bisexual or homosexual intercourse (40%) followed by intercourse with a commercial sex worker (8.7%). Among HIV-infected women in Puebla, heterosexual contact through unprotected intercourse is the primary mode of transmission (67%), followed by acquisition through commercial sex work (18%).²⁷

In the state of Puebla, the municipality with the highest incidence is the city of Puebla with 267.66 AIDS cases per 100 000 in 2008, more than 8 times as high as the AIDS rate of NYC in the same year. The second and third highest incidence rates are found in the municipalities of Izúcar de Matamoros and Acatlán de Osorio with 130.34 cases per 100 000 and 103.98 cases per 100 000 in 2008, respectively.²⁷

MIGRATION AND HIV TRANSMISSION A DISTINCT OR INTERRELATED PHENOMENA

The potential geographic link between HIV/AIDS in NYC and Puebla through migration trajectories warrants greater consideration of the HIV epidemics in each distinct location and possible interconnectedness between seemingly independent epidemics. Migration is one factor implicated in contributing to the HIV prevalence in Puebla and there are several plausible models of migration and HIV disease transmission.^28,29 Specifically, we explore 3 main issues: (1) the structural impact of migration as a risk factor for HIV transmission, (2) the importance of factors in the local context as a driver of transmission, and (3) the synergistic interaction between both migration and the local context to facilitate HIV risk.

Further complicating our discussion of migration’s role in HIV transmission is the diversity in the migratory paths of Mexicans, their motivations for migration, their stability and length of time in their current contexts, and the degree or continuity of connection with the home community.⁵ The variety in Mexican migrants’ experiences is essential for understanding their overall vulnerability to HIV. We consider 3 mechanisms critical for migration’s role in HIV transmission as applied to existing empirical evidence on Poblano migratory patterns between Puebla and NYC and corresponding indicators of HIV acquisition. In doing so, we hope to stimulate new perspectives related to the mechanisms by which migration is associated with HIV transmission and reframe both the public health research and programmatic agenda related to migration as a determinant of health.

THE STRUCTURAL IMPACT OF MIGRATION AS A RISK FACTOR FOR HIV TRANSMISSION

One critical mechanism that has emerged in the public health literature on HIV transmission emphasizes migration as a determinant of HIV transmission among Mexican NYC immigrants.^29–33 Overall, this literature suggests that migration functions as a fundamental contributor of HIV transmission.^29,34 According to this framework, depicted in Figure 2a, migration influences the structural and social factors that shape the context in which individual behavior takes place. Hence, migration affects HIV transmission through a 2-step sequence. First, migration causes shifts in behavioral norms, social support networks, and economic circumstances, which subsequently influence proximal determinants of HIV transmission (i.e., individual risk behaviors such as use of illicit drugs, alcohol use, or transactional sexual intercourse). As migration allows presumably low and higher risk populations to come into direct contact with each other in geographic areas of elevated vulnerability, the increased likelihood of population mixing affects HIV transmission.²⁸

FIGURE 2—

Key dynamics for examining HIV transmission and migration among Mexicans showing (a) migration as a structural determinant in HIV transmission, (b) the role of local factors as contributors to HIV transmission, and (c) the interplay between migration and local factors on disease transmission.

Empirical data demonstrate that many male Poblanos migrate to NYC for economic purposes as the availability of jobs for unskilled workers and established social networks with people already living in NYC yield employment opportunities. Conversely, many female Mexicans migrate to NYC to join family members or partners already living in the area.^21,35,36 As Mexican migrants locate north of the Mexican border, changes in behavioral norms and traditional values are coupled with diminishing familial and social support networks, which, in turn, leads to feelings of isolation and anxiety.^29,37,38 The combined experience of social isolation and anxiety are potentially detrimental to health and contribute to HIV vulnerability—namely by leading to increased illicit drug and alcohol use and involvement in high-risk sexual activity, such as transactional sexual intercourse.^30,34,39 One study found that Mexican migrants of both sexes were more likely to report injection drug use (9.8%) compared with nonmigrants (1.2%).²⁸ Other estimates suggest an even higher percentage of Mexican migrants use drugs compared with nonmigrants, with 21.5% of male migrants versus 7.2% of male nonmigrants reporting ever using any type of drug.⁴⁰

As Mexican migrants experience diversification of their social networks, they often report more sexual partners from high HIV prevalence populations including MSM, female sex workers, and intravenous drug users on the part of female Mexican migrants.^21,22 In addition, as migrants reunite with their families of origin, including women who join husbands or partners who engaged in risky behaviors, previous exposure to high-risk environments may facilitate HIV acquisition.²⁸ Additional shifts in structural and social factors include economic circumstances, such as remittances, which can create dependency on the receiving community and increase economic disparities within sending communities.^41,42 As families attempt to adapt to changes in the mechanisms of economic subsistence, stress on households can potentially increase and family well-being may be challenged, increasing the likelihood of risky behavior as individuals cope with these shifts.

Other data indicate that sexuality-related motivations compel Mexicans to migrate to NYC as they attempt to escape social oppression or stigmatization associated with their sexual identity in Mexico.⁴³ Compared with the perceived religious and conservative traditions in Mexico, the United States is viewed as a context in which individuals can access a more openly gay or bisexual life.⁴³ However, exposure to cultural factors, such as an “open and permissive American culture,” has been shown to exacerbate sexual risk behavior.^14,41,44 As previously mentioned, MSM constitute the majority of HIV cases among Latinos in NYC, which corresponds to a sexually motivated migratory pattern. For example, one study found that Mexicans who migrated internationally in the past year were more likely to engage in high-risk behavior compared with nonmigrants.²⁸ Specifically, the study found that male migrants had nearly twice the number of sexual partners compared with nonmigrant men (3.3 partners compared with 1.8 partners).²⁸ Another study also highlighted the potential influence of the “treatment optimism” mentality, where reduced concern about HIV acquisition because of the greater ability of treatment options in the United States may reduce protective behavior among gay and bisexual Mexican male migrants.⁴³ In these ways, migration operates as a structural determinant in HIV risk, resulting in greater likelihood of HIV infection.

Taken as a whole, these data illustrate the dynamic that Mexican migration to NYC influences the structural and social factors that shape individual risk behavior (Figure 2a). This mechanism emphasizes that exposure to a high-risk environment and subsequent shifts in behavioral, social, and normative influences account for the impact of HIV among Mexican immigrants. However, it is important to note that there are limited data on the specific migratory patterns pursued by Poblanos in NYC. Some evidence suggests that NYC is often the last destination for Mexican migrants after traversing long distances throughout other locations in the United States.¹⁸ Other analyses of migratory patterns indicate that many Poblanos first migrate to urban areas in their home country, such as Mexico City, before arriving in NYC.⁴⁵ As HIV risk among Poblanos in NYC may represent cumulative risk faced during the period of migration, the diversity in migratory movement within Mexico and the United States before and after arriving in NYC is a critical obstacle to assessing the impact of migration on HIV among Poblanos in NYC.

THE ROLE OF LOCAL FACTORS AS CONTRIBUTORS TO HIV TRANSMISSION

An additional framework for characterizing the potential migratory linkage between NYC and Puebla posits that the distinct local conditions of NYC and Puebla are predominately responsible for fueling the transmission of HIV in 2 unrelated epidemics (Figure 2b). This model places theoretical and practical emphasis on the local context of risk and HIV transmission in each of the 2 geographic areas rather than migration. Specifically, NYC and the state of Puebla presumably have local epidemics that are shaped and fueled by factors associated with each of the respective communities, which act as potential drivers of migration and are the primary determinants of HIV risk.

Analysis of contextual factors associated with HIV risk behavior in Puebla suggests that local context, which includes structural factors, social norms and attitudes, and the physical environment, contributes to the likelihood of HIV transmission.²⁸ For example, social norms around condom use indicate that condom use among married or cohabiting heterosexual couples in Puebla is low.⁴⁶ Cultural and religious influences and normative attitudes toward condom use in Puebla contribute to low and inconsistent usage among the population, increasing HIV vulnerability.⁴⁷ Moreover, data suggest that the distribution of condoms in Mexico among the population aged 15 to 64 years is inadequate and has been decreasing.⁴⁸ Because earlier data have identified heterosexual contact as the primary mechanism of HIV transmission in Puebla, this suggests that normative behaviors within the local context contribute to risk. Studies have also noted that the cultural values of machismo make it less likely that women will negotiate condom use during sexual intercourse, also contributing to HIV vulnerability.^28,49

Other characteristics of the Puebla context that contribute to HIV risk is the seeming “cultural acceptance” of commercial sex in Mexico.⁴⁴ Commercial sex work has been identified as one of the main mechanisms of HIV transmission in Puebla and is associated with gender and economic inequalities—factors identified to facilitate HIV transmission.⁵⁰ In addition, one study suggests that low levels of educational attainment among women in Puebla may translate into limited knowledge surrounding HIV/AIDS.⁴⁶ As individual knowledge about HIV risk has an impact on one’s efforts to protect against disease acquisition, the limited knowledge among individuals in Puebla about HIV transmission and the lack of information about the Mexican HIV epidemic may facilitate HIV risk behaviors. Hence, distinct from factors associated with migration are behaviors deeply embedded within local contexts. It is therefore possible that the local contexts of both Puebla and NYC each also distinctly support HIV transmission in unrelated ways.

Similarly, this dynamic (Figure 2b) also suggests that factors associated with the local context in NYC determine HIV risk. In the United States, reports of sexual behavior indicate that women are more likely to become HIV-infected through personal behavior such as injection drug use and having concurrent, multiple partners.⁵¹ Substance use, in particular, is an important characteristic of the local context of NYC that facilitates risk behavior. The popularity and availability of drugs in NYC has been widely documented and attributed to high-risk sexual behaviors, particularly among MSM.⁵² In addition, contextual factors such as housing instability or homelessness in NYC have been shown to contribute to risk behavior.⁵³ As the cost of living and appropriate health care expenses are often too high for individuals to maintain, homelessness increases exposure to risk factors that facilitate HIV transmission.⁵³ Therefore, this second mechanism highlights that the HIV epidemics in NYC and Puebla are each also associated with unique risk factors attributable to the local ecology of HIV risk. It is important to note, however, that there are limited data and research on local factors within Puebla that potentially drive HIV prevalence and transmission.

INTERPLAY BETWEEN MIGRATION AND LOCAL FACTORS ON DISEASE TRANSMISSION

A third, more complex mechanism to describe the relationship between migration and HIV transmission (Figure 2c), suggests that the influence of local contexts on HIV transmission is itself impacted by migration and the implications of mobility on individual behavior. Thus, it is possible that migrants contract HIV abroad (e.g., NYC) and introduce the disease to their region of origin by unknowingly infecting their partners. Yet, to significantly influence the epidemic in Puebla, local epidemic drivers, such as risky sexual behaviors, injection and noninjection drug use, HIV virulence, and social and economic inequities must also be at play.⁵⁴ This model suggests that where disease introduction and local ecology come together are the areas where the highest HIV prevalence occurs.

The distribution of reported AIDS cases and migration to New York among municipalities in Puebla in Figure 3 indicate such areas where migration and local context may be influencing HIV risk. For example, Figure 3 illustrates that the area with the highest number of AIDS cases, the city of Puebla, which accounts for 65% of all cases in the broader state of Puebla, is also an area with migration to New York, suggesting that in this municipality, migration and factors in the local environment may be interacting to dynamically escalate disease risk. Local contexts are dynamic, where social structures, norms, and attitudes can shift as a result of migration. As such, migration may well contribute to HIV transmission, but the local context in which HIV spreads must be identified and understood as well.

FIGURE 3—

Distribution of reported AIDS cases and migration to New York City among municipalities in Puebla, Mexico: 1984–2008.

^aInstituto Nacional de Estadística y Geografía.²⁷

^bConsejo Nacional de Poblacion, Mexico.⁵⁵

Figure 3 also demonstrates that in other Puebla municipalities we generally do not see spatial correspondence between migration to NYC and AIDS cases, suggesting that local drivers may not be in place in these contexts to facilitate the risk of transmission or that the local epidemics of these communities may be unrelated to migration. This means that to adequately attend to HIV risk, greater understanding of the migratory or local context that is driving risk is warranted and may have a significant impact on how HIV is addressed.

In communities where migration and local context interact to affect risk, the processes are intricate and interconnected (Figure 2c). For example, migration is an interrelated process that functions in a variety of ways depending on how, why, where, and what kind of migration occurs. Discussions surrounding HIV/AIDS and migration utilize broad or dissimilar definitions of migration (e.g., rural to rural, internal, cyclical, transmigration), all of which have different influences on patterns of risk behavior and their associated levels of HIV risk.^5,34 As Deane et al. argue, presenting migration as a singular and direct propagator of HIV or associated risk behaviors is too simplistic.³⁴ Migration and local context have levels of heterogeneity that relate and interact with one another in nonlinear and fluid ways to produce a synergistic effect on HIV transmission. For example, an equally important aspect of migration, but one that is often overlooked, is the influence of the social contexts and experiences of migrants before migration on the kind of life they live and HIV prevention challenges they face while in the United States.⁴³ Alternately, the life migrants live while away and specific vulnerabilities they encounter may also have a significant impact on their community of origin upon their return home. One example of this is the state of Puebla, where the labor force is characterized by out-migration such that migrants who encounter considerable emotional and structural hardship and subsequent HIV vulnerability constitute the majority of the workforce. HIV risk behaviors of migrants adopted in the receiving community in turn shape the familial or social networks of their community of origin when they return, and reset social norms about the adoption of risk behaviors while weaker control mechanisms to protect against risk may be in place.⁴¹

The study of HIV and migration must shift and reorient its emphasis toward multilevel models that consider migration’s role in shaping HIV risk along a causal pathway from the more distal (structural) factors to more proximal (individual risk behaviors) determinants of HIV, and recognize potential moderators of this relationship such as the nature of migration itself, the local risk ecology, and the impact of migration on the community of origin. By characterizing HIV transmission by situation and context, particular factors and modes of HIV transmission will become better understood and can further inform the development of targeted prevention interventions.

CONCLUSIONS AND PUBLIC HEALTH RECOMMENDATIONS

Although it is evident that significant cross-cultural migration is occurring between NYC and Puebla, with migrants influenced by contextual factors from their region of origin and the United States, multiple mechanisms account for the influence of migration on 2 geographically distinct HIV epidemics. A large body of extant research on the impact of migration on HIV transmission supports the first dynamic that migration functions as a structural determinant in HIV transmission where population mobility increases the likelihood of risk behaviors that lead to HIV exposure (Figure 2a). Data also support the second framework, in which the local context acts as drivers of the epidemic (Figure 2b). In this model social and cultural factors that characterize local contexts, distinct from the influence of migration, increase risk behaviors. The observed geographic distribution of disease in Puebla also appears consistent with the third mechanism that illustrates complexities between the relationship between migration and HIV (Figure 2c). This model indicates that, for migration to translate into a measurable effect in the HIV epidemic of the region, certain causal factors, or risk factors for disease, must be present in the local environment. In this scenario, migration is a necessary but insufficient cause of disease.

In this article, we address an important area for greater public health consideration, specifically the role of migration as a factor in HIV disease transmission. We draw upon the case example of Poblanos in NYC and Puebla to explore several dynamics by which migration may have an impact on HIV transmission. We highlight the numerous challenges in examining the relationship between migration and HIV among Poblano migrants and demonstrate the need to further characterize the Mexican migratory experience. Our discussion also makes clear the need to broaden understanding of proximal determinants of HIV infection that result from migration, local contextual factors that may drive transmission dynamics, and characteristics of the migratory process (e.g., reason for migration, length of time away, pattern of mobility) into an integrated framework to best account for individual HIV vulnerability. Expanded information about these mechanisms and their relative influence can direct interventions targeted for mobile communities that bridge high- and low-prevalence settings.

The current article thus represents an important first step in conceptualizing the role of Mexican migratory patterns on HIV transmission to be further explored in future research. A major limitation to better understanding the frameworks presented is the limited HIV/AIDS surveillance data among Mexican immigrants in NYC. Specifically, most HIV/AIDS surveillance data do not obtain information related to birthplace, length of residence in the United States, or travel and other connections to the home country,²² presenting challenges to documenting migratory patterns in relation to HIV/AIDS diagnoses. We provide public health recommendations to improve our understanding of the HIV epidemic in relation to migration and to address vulnerable populations in NYC and Puebla.

Specifically, initiatives to improve surveillance data and measure HIV among undocumented populations in NYC are necessary. New York City lacks a reporting infrastructure to adequately measure the incidence of HIV among undocumented migrants, as this population remains largely hidden and cautious.²² Similarly, although Mexico tracks the routes of migrants in the United States, there is little to no evidence documenting what proportion of HIV-infected migrants return home. In addition, there is lack of relevant data on local factors that potentially influence the HIV epidemic, particularly in regards to the municipality of Puebla, an area that holds the vast majority of reported AIDS cases in the entire state. Local contextual factors such as internal migration, barriers to HIV prevention, difficulties with accessing preventative services, HIV testing, and stigma are possible areas of inquiry that warrant further study on the HIV epidemic within Puebla.

In addition, increased research efforts are necessary to adequately understand the influence of migration on HIV transmission. Specifically, binational research and programmatic efforts are needed to adequately address the interconnectedness of the HIV epidemics of Mexico and the United States. The paucity of research that addresses both sides of the migratory dynamic of HIV transmission is particularly alarming in light of the fact that a growing proportion of Mexicans are leaving Puebla for NYC in search of new opportunities, and therefore an increasingly large population is vulnerable to HIV acquisition. Greater attention to the mechanisms and drivers of HIV transmission in both Mexico and the United States is needed to better respond to the health needs of Mexican migrants and stem the HIV epidemics of Puebla and NYC. These data can inform targeted interventions in locations with known bridges between high and low HIV-prevalence communities. These interventions should incorporate knowledge of local drivers of the epidemic, geographic connectedness with other settings, who the most at-risk migrants are and their needs, and specific transit stations that can be targeted to best increase access to services and mitigate the impact of migration on HIV risk.