AIDS in Mexico: lessons learned and implications for developing countries

Introduction Although anecdotal evidence suggests that HIV infections in Mexico were occurring in 1981, the first cases of AIDS in Mexico were documented in 1983. Since then, approximately 50 000 cases of AIDS have been reported nationwide and it is estimated that there are approximately 150 000 HIV-infected persons living in Mexico [1,2]. While it could be argued that there is some underreporting of AIDS in Mexico [2,3], the epidemic is still significantly less intense than that to the north (USA) or south (Central American countries, e.g. Honduras). One possible explanation for this is that, unlike in the countries surrounding it, the epidemic in Mexico has remained ‘nuclear', primarily affecting men who have sex with men in urban areas of the country such as Mexico City, Guadalajara, Monterrey and Tijuana [4]. This relative containment of the epidemic is by no means accidental but rather the end result of many prevention efforts conducted by the government as well as by community-based organizations. The national response to AIDS in Mexico was early and strong, beginning shortly after the first cases were reported in 1983. HIV testing began the first year the test was available (1985) and in February of 1986 the National Committee for AIDS Prevention (CONASIDA) was founded. In 1988 a Presidential Decree transformed CONASIDA from a committee to a ‘National Council', thus giving it a multisectorial composition that went beyond the scope of individual health sector response. While early national-level attention toward containing the epidemic has benefited the population at large, it is clear that prevention efforts of the Mexican government have been most successful in two areas: in the control of transfusion-transmitted HIV and in preventing infections among female commercial sex workers. Because HIV infection through blood and blood products represents only a small proportion of all cases of HIV/AIDS worldwide it has not received the attention this means of transmission merits [5]. Not only is it the most efficient way in which HIV can be transmitted, but transmission via blood and blood products is also the route most amenable to government control. As a result, devoting attention and resources to insuring the safety of the blood supply represents a unique opportunity and a cost-effective intervention for public health authorities to dramatically change the course of HIV infection in a given country. The changing epidemiology of AIDS in Mexico provides compelling proof of this conclusion. With the exception of patients with hemophilia, transfusion-transmitted HIV in developing countries primarily affects women – specifically women who receive blood for obstetric reasons [6]. Because of this observation, a country with a large proportion of infected women may overestimate the level of ‘heterosexual’ transmission, overlooking a hidden blood and blood products connection. For example, in 1986 there were 26 cases of AIDS in men for every one in women (26 : 1) in Mexico. Four years later, at the same time that the highest proportion of transfusion-transmitted cases were being reported nationwide, the number of infections among women had climbed so dramatically that the ratio dropped to five cases of AIDS in men for every one in women (5 : 1). Then, in 1999, the first year in which no transfusion-transmitted AIDS cases were reported in Mexico, the trend in male-to-female cases reversed direction ( for the first time ), with six cases of AIDS being reported in men for every one in women (6 : 1). In many countries, infection of the blood supply is chiefly an economic phenomenon. For example, prior to 1987, selling one's blood or plasma was such an attractive source of income for many impoverished Mexicans that commercial blood and plasma donors (who had, by definition, no inducement to know their HIV status prior to donation) formed a significant percentage of total blood suppliers. Thus, the control of transfusion-transmitted HIV in Mexico not only involved mandatory HIV testing but also banning the commercialization of blood and closing of commercial plasmapheresis centers. As noted above, this policy has all but eliminated HIV from the Mexican blood supply. Blood transmission of HIV in other countries continues to be a significant problem. Recent reports from China suggest that paid blood donors may be playing an important role in the spread of HIV there [7]. The impact of commercial sex on HIV transmission is well known and has long been considered a critical vector for the introduction of HIV infection into the general population [8,9]. As a result, interventions to limit the extent of HIV infection among commercial sex workers (CSW) are frequently viewed as a priority in many national prevention campaigns [10]. Perhaps the best-known of the successful interventions with CSW to date is the ‘100% condom use in brothels’ initiative in Thailand [11]. This initiative has lead to a marked decrease in HIV incidence among Thai military recruits as well as to a decrease in the incidence of other sexually transmitted infections in that country. In contrast to Thailand and many other countries though, HIV seroprevalence among female CSW in Mexico has remained low since the beginning of epidemiological investigation, with seroprevalence averaging below 1% in large, repetitive serosurveillance studies. This finding suggests that many of the early interventions targeting CSW in Mexico might have limited the impact of HIV in this group. Yet, it could also be argued that the nuclear epidemiology of HIV in Mexico described above has simply meant that female CSW in Mexico are at less risk of exposure to infection than CSW in other countries. If this observation is so, the low seroprevalence among Mexican CSW may not be credited to public health intervention but rather reflect lack of opportunity to be exposed to HIV. In this article, we will review the major interventions conducted to date in Mexico as part of the National AIDS Prevention and Control Program. We will also review the available data published in journals or presented at the International AIDS Conferences for insights into Mexican HIV prevention successes and failures that may have implications for AIDS programs in other developing countries. The control of HIV transmission through blood and blood products When the AIDS epidemic began in Mexico in the early 1980s there was no coordinated system of blood procurement and a large proportion of the blood available in the country was obtained from paid donors. In addition, an unknown number of commercial plasma collection centers throughout the nation also obtained their products from paid donors. Evidence now suggests that these centers frequently re-used blood collection in the introduction of HIV to donors. As a result, not only the centers and infected blood but also as an efficient means for that by HIV to the plasmapheresis the impact of transfusion-transmitted HIV on the AIDS epidemic in Mexico had been In only years blood and blood AIDS in Mexico went from being of to of all 1987, paid blood and plasma donors approximately of all blood products in Mexico a paid be a from a who had to one of the that large Mexico City, Guadalajara, Monterrey and be and had no risk for HIV infection prior to the opportunity from a or a at one of the blood or plasmapheresis being paid to as frequently as the individual policy as as every or The the risk for infected with HIV the blood collection If that infection into the national blood supply – and to other donors at the same as well – might also HIV to or sex through to In of HIV testing of all blood donors mandatory in Mexico, the extent of the of HIV among paid donors first began to In two but 1986 and 1987, a of was among paid donors to a seroprevalence of only among persons who blood evidence of the health risk by paid donors in Mexico at that time is their seroprevalence is to that of donors or donors When the data were the scope of the risk by paid donors dramatically For example, the among paid donors at one plasmapheresis in from in 1986 to in of the same year was documented in of these this of this population that a of or was with HIV As described above, it is that donors were infected with HIV the plasmapheresis as a result of infection control The of plasmapheresis of or and the of small of infected plasma or As the number of was as as it is that the infection was into a blood or plasma donors infected at the blood or plasma at the time of In the first of AIDS in a Mexican paid plasmapheresis was reported and by the of this mandatory in Mexico a was in Mexico and by the the blood paid is not reported as a risk in many epidemiological reports and thus it may not be as an important to the spread of HIV in a given country AIDS cases in Mexico in by risk group. Mexico of 1987, as a of by blood and plasma with the 1986 that HIV of blood and blood the and of the government a the of blood and blood products in Mexico This was not and Since Mexico a of blood of HIV and an blood collection there was a major among public health that the blood and plasma the blood the of a in blood and blood Because of this a response was and blood were all the country at the same the for HIV testing was a of of donors for HIV was in the In addition, blood collection and centers were in with the Mexican the by Mexico for the control of transfusion-transmitted The Prevention of transfusion-transmitted HIV in Mexico. The of the described above has had for public health in Mexico. Not only is the health of the general public – the number of cases a year of the blood and no cases of AIDS to blood have been reported since 1) – but so is the health of blood donors. paid donors were in the HIV seroprevalence among donors from in 1986 to in 1988 [6]. In HIV seroprevalence among blood donors in Mexico and has remained low in all For example, only of blood for HIV in and of were HIV infected in and As a result of the change in government it is estimated that transfusion-transmitted infections have been AIDS cases with blood in Mexico by date of HIV among blood Mexico the National HIV is a for but the extent of the by the paid system has to be to cases of AIDS among paid donors were reported to the National AIDS this transmission of HIV was This number of cases represents than reported among in Mexico to cases of AIDS considered to of HIV infected blood have been and for only the infections As noted above, many of the paid as well as the of blood and blood products may have infected their sex This is a the was women in Mexico – women – were at risk from blood from not one but two were at risk via blood and were at risk from who were donors and who were infected at the time of blood or plasma We that it is this that Mexican women that to the in : female ratio of AIDS cases in the 1980s and the of the AIDS is to that the now on the blood supply in Mexico, this have and the : female ratio of infection have to decrease Mexico a for this may be by the of the : female ratio in countries that to a paid blood collection For example, in areas of and China epidemic HIV infection in paid donors has been the epidemic has ‘heterosexual’ for this may also be in the of a to the risk for among women in Mexico. women who had an HIV test in that only a of blood low and sex with an HIV infected were with being HIV-infected In the Mexican the critical role that mandatory of all paid and control of the plasma can have on the epidemiology of control resources above will for their The prevention of HIV infection among female commercial sex workers sex in Mexico in the of Mexico one of two or The to by a though, is but by The system to areas of the or and to be and have health of Mexico for the Mexico is and the of Mexico, and a The public health by the system – specifically the for health – is the for sex might have the opportunity to a and the for a of on the part of CSW This of which may lead some to or on sex a is not a of health are not to from HIV infection or sexually transmitted infections is among public health the or provides a system for preventing HIV infection among sex workers. to suggest that and sex workers and their as condom use in can be the of a successful of public health safety sex in Mexico an system that has been in since the of commercial sex was first in that In Mexico City, individual who is commercial sex may be and for this the are also to women who are on the simply their is considered to and there is no evidence that the women were in the of CSW is and not are or This is In the Mexico of health that of men reported their first with a CSW The proportion of men who have been of CSW their is this system CSW in a status and of health and This in the of and other authorities who from In 1986 an CSW that, in may have been in the Mexican AIDS epidemic to nuclear In that female CSW began at National AIDS (CONASIDA) and to HIV testing and risk In these women an opportunity for public health to to an population that is and of with the CONASIDA began to to with these women and into the public health Perhaps the most intervention that this time was a the of in Mexico and the of that CONASIDA to a of and interventions with sex workers the of the In this way CONASIDA was to with sex workers and their to testing of early that HIV incidence among female CSW in Mexico was below 1% in the 1980s and has remained low since among women for HIV in This finding is in marked contrast to the of HIV among CSW in Mexico or to the epidemic among and female CSW in other countries. the same time for example, the HIV seroprevalence for sex workers in Thailand from in 1988 to in of HIV among sex workers has been in and on the seroprevalence of HIV among CSW who are in a CONASIDA it is that described below may have a low of HIV among female CSW in Mexico, the that HIV has remained low to this could also be to condom use other women in Mexico, are to HIV in one or of through the of blood or blood products or for obstetric through the use of through infection at the time of blood or plasma blood plasma or through sex with a who is HIV For the to be – that low HIV in female CSW is not primarily to condom use – it be to evidence that the of transmission described above in a risk for HIV infection to female the result could that other or means of than transmission from of In to and evidence be in to the at the of and CONASIDA was and was not known the transmission from blood or blood products As noted above, transfusion-transmitted HIV primarily affects specifically women who receive blood for obstetric reasons [6]. was no evidence that female CSW in Mexico were at less risk of blood than other the low of HIV among female CSW was to a risk from was no that HIV may be transmitted via by or was in was the low of use among female among CONASIDA and in was to for the low of HIV among as For other countries with a low of use among female CSW have the incidence of HIV dramatically in their female CSW the low of use among female CSW in Mexico the of HIV in this it not to be than condom use for the low of HIV. infection at the time of blood or plasma As has been described above blood and plasma donors infected with HIV this was in was thus possible that could also have been donors and thus be at risk for HIV infection through this of cases of AIDS among blood donors have been among which is by the that men were to be donors. from sex are at in which in the of may be with a low of HIV among female an HIV seroprevalence in the general population to a significant transmission the of HIV is not spread throughout the population and infected not female and the in by CSW not HIV In the first the low of HIV in the general population of Mexico in 1986 six meant that sex workers as a risk of exposure from their The with this explanation was that had a of in many American countries was that evidence be a could be that are less to female CSW than CSW and that, the risk for infection from this was than for female In the it was that female CSW not considered to be of risk with their so the or of a For the of of transmission and evidence be a could be that female CSW in Mexico or only in HIV As a result of the in a major was in observation, and to a of commercial sex in the urban of Mexico This the of and commercial sex this it was estimated that approximately of the population of Mexico were women in commercial sex 000 of these women were to in a which as well as testing for and The of these a low of among female sex workers and the which that the HIV among these women was low significant was also the risk of an and the of a have of In addition, a level and the number of years commercial sex were with being for HIV and among female commercial sex workers in Mexico. from The of the were also of major While all women reported with their reported sex and In addition, reported an in condom use since in contrast to their with their reported with their or In risk for sex with a low no use of a to use of and use of the years conducted in Mexico as well as in other throughout the country have to a low of HIV among female commercial sex workers As noted above, this finding is in marked contrast to the HIV seroprevalence among sex workers in other developing HIV among female commercial sex workers in Mexico. In an to and to risk for HIV infection among men in Mexico, a of have been conducted by group. that men at and had a seroprevalence of HIV infection than men and that reported condom use was with only condom use As noted above, the of has been reported to be among American men in to a of men conducted in this to not be as in Mexico in In that of men reported that had sex in their with and The HIV in this was among men and among men This also that men might be to the of or female CSW not in a was an to only a of men were being in a This finding that female CSW in Mexico may have sex with men who are sex with men less frequently than was This finding provides for the that the population of by and female CSW in Mexico is not are to the risk of HIV exposure to female CSW in the of condom use among men This evidence suggests that the of condom use reported by female sex with the of and female CSW in for the low of transmission among female CSW in Mexico for this may be through from the among HIV women who were not sex workers these a of sex with an infected was an important risk for HIV and a of female sex workers with an of infection of that and to use as a of were with infection The suggest that sex workers who for are with and sex we lack data to the of condom use among female CSW in Mexico and this in be workers know that public health authorities condom use and so may be to to CONASIDA In the epidemiology of the AIDS epidemic in Mexico suggests that the use of by female CSW may be a major the HIV/AIDS epidemic in Mexico has remained This finding provides a compelling for a of AIDS prevention resources female commercial sex workers and their two a that is to or the of HIV infection in the general be to sex for CSW and their level and interventions that the of of be In addition, these interventions all involved in the sex As in ‘100% condom campaigns a in which condom use with CSW is as the not an [11]. on the sex and mandatory HIV testing in the of for have not to be for sex workers in Mexico or the interventions Prevention of HIV infection among men who have sex with men As described above, the AIDS epidemic in Mexico began and continues to be primarily an epidemic to and the end of of the cases of AIDS that had been reported in Mexico in men in Mexico with sexually are as as and as As above, the percentage of ‘heterosexual’ cases may also be as some of may be occurring among men who have sex with men As early as a of seroprevalence conducted among men who have sex with men in Mexican reported as as for Mexico In of the National that the HIV seroprevalence among men in Mexico was As a result of these and other interventions were to condom use among men who have sex with to condom were the interventions among men who have sex with men have thus been limited and resources be to HIV infection among as to be the population most Prevention of HIV infection conducted among women as part of have been conducted in Mexico since 1988 and and a total of women have been through this and have been to be HIV infected Not only has seroprevalence remained low in this but no significant have been noted the seroprevalence among women in Mexico is low the large number of in Mexico means that there is a significant number of at risk for being the seroprevalence reported above, as many as HIV-infected could be year in Mexico. In the of in Mexico began a to the number of HIV by to for all HIV-infected women who to be As a result of this there has been a decrease in the number of HIV infected who have been reported in Mexico this has only been primarily the low of HIV infection has of HIV infected women and many HIV infected women are not This finding suggests that preventing HIV infection in a low country Mexico have the of HIV testing and the of HIV testing into as can be available to HIV infected women who of the risk This has been the of AIDS to to transmission, Mexico – of National of AIDS for HIV-infected persons to and for with HIV into the National AIDS Prevention in with the of a CONASIDA for the of with This was by a of and all that the Mexican health sector have This has been frequently as was and of Mexico has also an for This has the time for from years to no than most available in the are in of the of a in the it for and by the Mexican to it of to patients who are to receive the system As a result, HIV infected persons who are to receive have had to since as of the end of than of the living with AIDS in Mexico not have to by to In response to this long in to later, for who could not receive it at the were by CONASIDA as early as the end of these to the of for the large of HIV-infected persons living in Mexico and were The to these in the of the to the role that the of health has in the HIV/AIDS epidemic in Mexico. The introduction of to the AIDS prevention in a of among AIDS in Mexico who a for AIDS from the of such a conducted in that the of in Mexico to a with HIV – that with a – was with of the for by the In it was estimated that to all patients have or approximately of the health at that time In from AIDS was successful in an AIDS The major of was to via from the and donors for the and of to patients who not have or other was to of patients years as well as to HIV infected women for the prevention of transmission and for HIV for the after only of persons living with HIV/AIDS could be by the available the was still in a Mexican to HIV/AIDS into the of the of The of in Mexico has and data suggests that has as a result of that AIDS in Mexico among men years has also from 000 in to 000 in and the of have is from being and resources are still a to that in in is to be in Mexico. and are to change the epidemiology of HIV/AIDS in and an from Mexico to the is not a but is is the that as many as of AIDS cases in Mexico are among who have been in the in contrast to of in urban areas The first of AIDS from a of Mexico was reported in 1986 and only of AIDS cases can be considered from with than such cases are from reported from urban centers. For example, of cases are among women as to of urban cases of these women are or sex of workers who may be of the of their in suggest that Mexican men at risk for HIV infection HIV infection be considered a for the and Mexico and efforts be on of the to and limit the impact of HIV infection among The prevention of HIV infection a early and than the through and coordinated interventions can the impact of HIV be limited in a a the most successful public health intervention that Mexico early in the epidemic was the control of blood supply through mandatory of paid and the of plasmapheresis As has been in Mexico, could have a major impact in the HIV epidemic of many developing countries who are to their blood supply The interventions among female CSW have also been successful and be as this population is and is as well as sex workers. as it was and as has been in there be policy and level interventions that condom use the and the in commercial As we reflect on the and failures of HIV prevention in Mexico, it is clear that the of into policy a major role in the of the This of and policy in which prevention programs are be the as it has been noted from the with in the this is not the The is that and not HIV/AIDS Prevention The for and review of the