• 1

    Linares L, Vinelli E, eds., 1994. Taller Latinoamericano de Servicios de Transfusión Sanguínea y óptimo uso de los Recursos. Caracas, Venezuela: Cruz Roja Finlandesa.

  • 2

    Schmunis GA, Zicker F, Pinheiro F, Brandling-Bennett D, 1998. Risk of transfusion transmitted infectious diseases in Central and South America. Emerg Infect Dis 4 :5–11.

    • Search Google Scholar
    • Export Citation
  • 3

    Zuna H, La Fuente C, Valdez E, Recacochea M, Franco JL, Romero A, Bermudez H, 1985. Estudio prospectivo de la transmisión del Tripanosoma cruzi por vía sanguínea en Bolivia. Ann Soc Belg Med Trop 65 (Suppl. 1):107–113.

    • Search Google Scholar
    • Export Citation
  • 4

    Carrasco R, Miguez H, Camacho C, Echalar L, Revollo S, Ampuero T, Dedet JP, 1990. Prevalence of Trypanosoma cruzi infection in blood banks of seven departments of Bolivia. Mem Inst Oswaldo Cruz 85 :69–73.

    • Search Google Scholar
    • Export Citation
  • 5

    Landivar WHC, Nakasa T, Tachibana H, Paz KC, Tateno S, 1992. Seropositivity to Tryapanososma cruzi in blood donors in Santa Cruz, Bolivia. JID 166 :1464–1465.

    • Search Google Scholar
    • Export Citation
  • 6

    Zuna H, Gianella A, 1991. 92/93. Infeccion por T. cruzi en donantes de sangre en Santa Cruz, Bolivia: (Influencia de la migracion). Bol Cient Centro Nacional de Enfermedades Tropicales 15 :60–64.

    • Search Google Scholar
    • Export Citation
  • 7

    Miyoshi C, 1995. The cost effectiveness of blood donor screening programs to identify transfusion transmitted Chagas disease in Bolivia, including the use of a natural history model of Chagas’ disease. Takemi Program in International Health, Harvard School of Public Health.

  • 8

    Pan American Health Organization, 2005. Transfusion Medicine in the Caribbean and Latin American Countries, 2000–2003. Washington, DC: Pan American Health Organization.

  • 9

    Schmunis GA, Zicker F, Segura EL, Del Pozo AE, 2000. Transfusion-transmitted infectious diseases in Argentina, 1995 through 1997. Transfusion 40 :1048–1053.

    • Search Google Scholar
    • Export Citation
  • 10

    Schmunis GA, Zicker F, Pinheiro F, Cruz JR, Cuchi P, 1991. Safety of blood supply for infectious diseases in Latin American countries, 1994–1997. Am J Trop Med Hyg 65 :924–930.

    • Search Google Scholar
    • Export Citation
  • 11

    Schmunis GA, Cruz JR, 2005. Safety of the blood supply in Latin America. Clin Microbiol Rev 18 :12–29.

  • 12

    United States General Accounting Office, 1997. Report to the Ranking Minority Member Committee on Commerce, House of Representatives. Blood Supply. FDA Oversight and Remaining Issues of Safety. GAO/PEMED-97-1. Washington, DC: United States General Accounting Office.

  • 13

    WHO/UNAIDS, 1998. Operational Characteristics of Commercially Available Assays to Determine Antibodies to HIV-1 and/ or HIV- 2 in Human Sera. Report 9–10. Geneva: World Health Organization.

  • 14

    WHO/UNAIDS, 1999. Operational Characteristics of Commercially Available Assays to Determine Antibodies to HIV-1 and/ or HIV-2 in Human Sera. Report 11. Geneva: World Health Organization.

  • 15

    World Health Organization, 2001. Hepatitis B Surface Antigen Assays: Operational Characteristics. Report 1. Geneva: World Health Organization.

  • 16

    Couruce AM, Le Marrec N, Girault A, Ducamp S, Simon N, 1994. Anti-hepatitis C virus (anti-HCV) seroconversion in patients undergoing hemodialisis: comparison of second- and third-generation anti-HCV assays. Transfusion 34 :790–795.

    • Search Google Scholar
    • Export Citation
  • 17

    Uttendaelle S, Claeys H, Mertens W, Verhaert H, Vermylen C, 1994. Evaluation of third generation screening and confirmatory assays for HCV antibodies. Vox Sang 66 :122–129.

    • Search Google Scholar
    • Export Citation
  • 18

    Vrielink H, Reesink PJ, van den Burg PJM, Zaaijer HI, Cuypers HTM, Lelie PN, van der Poel CL, 1997. Performance of three generations of anti-hepatitis C virus enzyme-linked immuno-absorbent assays in donors and patients. Transfusion 37 :845–849.

    • Search Google Scholar
    • Export Citation
  • 19

    World Health Organization, 2001. Hepatitis C Assays: Operational Characteristics (Phase 1). Report 2. Geneva: World Health Organization.

  • 20

    Qelemann WM, Teixeira MD, Verissimo da Costa GC, Borges-Pereira J, De Castro JDF, Coura JR, Peraltan JM, 1998. Evaluation of three commercial enzyme-linked immuno-sorbent assays for diagnosis of Chagas disease. J Clin Microbiol 36 :2423–2427.

    • Search Google Scholar
    • Export Citation
  • 21

    Donegan E, Stuart M, Niland JC, Sacks HS, Azen SP, Dietrich SL, Faucett C, Fletcher MA, Kleiman SH, Operskalski EA, 1990. Infection with human immunodeficiency virus type 1 (HIV-1) among recipients of antibody-positive blood donations. Intern Med 113 :733–739.

    • Search Google Scholar
    • Export Citation
  • 22

    Schreiber GB, Busch MP, Kleinman SH, Korelitz JJ, 1996. The risk of transfusion-transmitted viral infections. N Engl J Med 334 :1685–1690.

    • Search Google Scholar
    • Export Citation
  • 23

    Aach RD, Stevens CE, Hollinger FB, Mosley JW, Petersen DA, Taylor PE, Johnson RG, Barbosa LH, Nemo GJ, 1991. Hepatitis C virus infection in post-transfusion hepatitis. An analysis with first-and second-generation assays. N Engl J Med 325 :1325–1329.

    • Search Google Scholar
    • Export Citation
  • 24

    World Health Organization, 1991. Control of Chagas disease. WHO Tech Rep Ser No. 811 :32.

  • 25

    Cerisola JA, Rabinovich A, Álvarez M, Di Corleto CA, Pruneda J, 1972. Enfermedad de Chagas y la transfusión de sangre. Bol. Ofic Sanit. Panam. 73 :203–221.

    • Search Google Scholar
    • Export Citation
  • 26

    Attias A, Lorca M, Canales M, Mercado R, Reyes V, Child R, 1984. Chagas disease: transmission by blood transfusion in Chile. Bol Hosp San Juan de Dios (Santiago) 31 :301–306.

    • Search Google Scholar
    • Export Citation
  • 27

    Lorca M, Lorca J, Child R, Attias A, Canales M, Lorca E, Gutiérrez J, 1988. Prevalencía de la infección por Trypanososma cruzi en pacientes politransfundidos. Rev Med Chil 116 :112–116.

    • Search Google Scholar
    • Export Citation
  • 28

    Organización Panamericana de la Salud, 2003. Medicina Transfusional en América Latina 1994–2003. Document OPS/EV-LAB/01.2003. Washington, DC: OPS.

  • 29

    Lackritz EM, Satten GA, Aberle-Grasse J, Dodd RY, Raimondi VP, Janssen RS, Lewis WF, Notari EPI, 1995. Estimated risk of transmission of the human immunodeficiency virus by screened blood in the United States. N Engl J Med 333 :1721–1725.

    • Search Google Scholar
    • Export Citation
  • 30

    Schreiber GB, Busch MP, Kleinman SH, Korelitz JJ, 1996. The risk of transfusion-transmitted viral infections. N Engl J Med 334 :1685–1690.

    • Search Google Scholar
    • Export Citation
  • 31

    Ministerio de Sanidad y Consumo, Direccion General de Salud Publica. Plan Nacional de Hemoterapia, 1998. Estadistica Estatal de Centros de Transfusion y Bancos de Sangre. Año 1997.

  • 32

    Sookvian S, Castano G, Castiglioni T, Pilar S, Videz P, Gonzalez J, Frider B, 1997. Problematica de la infeccion por el virus de la hepatitis C en donantes de sangre. Medicina (Buenos Aires) 55 :699–707.

    • Search Google Scholar
    • Export Citation
  • 33

    Wendell S, Gonzaga A, 1993. Chagas’ disease and blood transfusion: a new world problem? Vox Sang 54 :1–12.

  • 34

    Salles N, Sabino EC, Cliquet MG, Eluf-Neto J, Mayer A, Almeida-Neto AC, Mendonca MC, Dorliach-Llacer P, Chamone DF, Saez-Alquezar A, 1996. Risk of exposure to Chagas disease among seroreactive Brazilian blood donors. Transfusion 36 :969–973.

    • Search Google Scholar
    • Export Citation
  • 35

    Lorca M, Child R, Garcia A, Silva M, Osorio J, Atlas A, 1992. Evaluacion de reactivos comerciales empleados en el diagnosticode la enfermedad de Chagas en bancos de sangre de Chile. I. Selección de reactivos. Rev Med Chile 120 :420–426.

    • Search Google Scholar
    • Export Citation
  • 36

    Lorca MH, Child RB, Garcia CA, Silva MG, Martinez LP, Jerez JM, Toledo ID, Mezzano DA, 1994. Evaluacion de reactivos comerciales empleados en el diagnostico de la enfermedad de Chagas en bancos de sangre de Chile. II Aplicación rutinaria. Rev Med Chile 122 :925–931.

    • Search Google Scholar
    • Export Citation
  • 37

    Saez-Alquezar A, Luquetti AO, Borges Pereira J, Furtao EM, Gadelha MFS, Garcia-Zapata MT, Arruda AHS, 1997. Estudo multicentrico: avaliacao do desempenho de conjuntos diagnosticos de hemaglutinacao indireta, disponiveis no Brasil, para o diagnostico sorologico da infeccao pelo Trypanosoma cruzi.Rev Patol Trop. 26 :343–374.

    • Search Google Scholar
    • Export Citation
  • 38

    World Health Organization, 2002. Control of Chagas disease. Geneva: World Health Organization.

  • 39

    Zuna H, Gianella A, 1991. 92/93. Enfermedad de Chagas en donantes de sangre en Santa Cruz de la Sierra. Bol Cient CENETROP 15 :65–69.

  • 40

    Bossuyt M, Torrez R, Coenen J, Herteleer J, 2002. Banco de Sangre Regional—Santa Cruz 1994–2002. Informe Final. Brussels, Belgium: Projecto Sistemas Locales de Salud Santa Cruz, Cooperacion Tecnica Belga.

  • 41

    Pinto Diaz JC, 2007. Southern Cone initiative for the elimination of domestic populations of Triatoma infestans and the interruption of transfusional Chagas disease. Historical aspects, present situation, and perspectives. Mem Inst Oswaldo Cruz 102 (Suppl. 1):11–18.

    • Search Google Scholar
    • Export Citation
  • 42

    Pan American Health Organization, 1999. Strengthening blood banks in the Region of the Americas. 124th Session of the Executive Committee. Resolution CD41 :R15.

    • Search Google Scholar
    • Export Citation

 

 

 

 

Prevention of Blood-borne Diseases in Bolivia, 1993–2002

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  • 1 Pan American Health Organization/World Health Organization, Washington, DC; Regional Blood Bank, Santa Cruz, Bolivia; Institute of Tropical Medicine, Antwerp, Belgium; Pan American Health Organization, Guatemala City, Guatemala; National Center for tropical Diseases, Santa Cruz, Bolivia

This report shows the outcome of a coordinated effort by locals, foreign institutions, and an international agency, from 1996–2002, aimed at preventing transmission of blood-borne diseases in Santa Cruz, Bolivia. From 2001–2002, testing the donor pool for HIV prevented transfusion of 32 infected units and 29 infections. With 100% screening coverage, 196 hepatitis B virus (HBV)-infected units were discarded, and 177 infections of HBV were prevented between 1999 and 2002. Incomplete screening for hepatitis C virus (HCV) may have tainted nine units of blood and generated eight HCV infections in 1999. On the other hand, 600 units infected with HCV were discarded, and 540 HCV infections were prevented between 1999 and 2002. Screening for Chagas disease prevented transfusion of 10,661 tainted units and 2,133 infections from 1999 to 2002. From 1996–2002, the investment was US$1,108,000.

INTRODUCTION

In the 1980s and early 1990s, prevention of blood borne diseases in Latin American countries was difficult, even when policies were in place and effective control strategies had been known for years, because resources may not have been available or the capability of countries to enforce compliance with norms, and regulations were weak. In several countries, there were multiple public and private blood banks, each providing limited number of units of whole blood, in which norms of quality assurance were unknown or not followed, thus decreasing the safety of the blood supply.1 This was especially true in Bolivia, where official data indicated that, of the total pool of blood donors, only 36% were screened for HIV, 15% for hepatitis B virus (HBV), none for hepatitis C virus (HCV), and 29% for Chagas disease in 1993.2 At that time, country-wide estimated prevalence’s were 0.1 and 2.0 per 1,000 donors for HIV and HBV respectively, and were unknown for HCV.2 On the other hand, country-wide prevalence for Chagas disease was 148.0 per 1,000 population,2 but there were areas of the country, like the department of Santa Cruz, where up to 50% of the population was infected with Trypanosome cruzi.36

We report how coordinated actions carried out by local, foreign institutions, and an international agency from 1996–2002 prevented transmission of blood-borne diseases in Santa Cruz, Bolivia, which at the time was the second largest city in the country (today it has the largest population); how much investment was needed; and how this investment impacted the outcome: transmission of blood-borne infections in that area from 1999–2002.

MATERIALS AND METHODS

Sources of information.

Information was obtained from the agencies/institutions involved. The percentage of donors screened (screening coverage) for the different infectious diseases’ serologic markers, the prevalence of the serologic markers, and estimates of blood transmitted diseases for Santa Cruz in 1993 were compared with those of 1999–2002 in the same city and with the situation in the country as a whole in 1993, 2001, and 2002.

Although 1993 data for the country as a whole were official information provided by the Ministry of Health,2 there were no matching records from the Santa Cruz Blood Bank for that year. Therefore, basic data for Santa Cruz in 1993 were based on several assumptions. Assumptions were also made regarding the nationwide prevalence of HCV in 1993 and the prevalence of all serologic markers in 2002 (Table 1).

Assumptions.

The number of blood donors in Santa Cruz was reported to be 13,708 for 1993.7 The number of transfusions in Santa Cruz reached at least 10,000 in that year.6 It was assumed that screening coverage in 1993 was similar to that reported for the whole country in that year: 36% for HIV; 15% for HBV; unknown for HCV; and 29% for T. cruzi.2 The assumed prevalence rate in Santa Cruz for the different serologic markers in 1993 was that reported for 1994: 0 for HIV; 3/1,000 for HBV (HBsAg), the lowest end of the prevalence reported in Santa Cruz at that time; and 471.5/1,000 for T. cruzi (Table 1).7 The prevalence for the latter is the upper end of the prevalence range found in four general hospitals of Santa Cruz but a lower prevalence than that reported in Santa Cruz blood donors in 1990 (510/1,000),4 1992 (490/1,000),5 and 1993 (485/1,000).6 Screening for HCV was not available in the country in 1993, so we assumed a prevalence rate of 5/1,000 for HCV in Santa Cruz, the lowest prevalence reported in a survey of blood donors at Santa Cruz in 1992.7

The Ministry of Health did not report the nationwide prevalence of HCV in 1993 or the prevalence of all serologic markers in 2002.2,8 Therefore, it was assumed that the nationwide prevalence of HCV in 1993 was the same as in Santa Cruz in 1992 (i.e., 5/1,000),7 whereas the prevalence of infectious diseases markers per 1,000 donors in 2002 was similar to that found nationwide in 2003: 1.0 for HIV; 3.8 for HBV; 8.9 for HCV, and 76.5 for T. cruzi.8 (Table 1)

Calculations.

Positivity for T. cruzi in Santa Cruz was so high that in 2002 blood donors were screened for T. cruzi infection by indirect hemagglutination (IHA) before withdrawal of blood. Only donors negative for T. cruzi were permitted to donate. This strategy prevented waste by saving blood bags and avoiding serology for viral diseases in units of blood that would have been discarded because of T. cruzi infection. Of 7,002 potential donors in 2002, 1,649 were rejected after screening for T. cruzi infection (prevalence equal to 235 per 1,000 donors). The remaining 5,353 donors negative for T. cruzi were asked to donate. Serology for viral diseases and T. cruzi (enzyme immunoassay [EIA]) was repeated. Positive serology for T. cruzi was still detected in 1,738 donors, a prevalence of 324.7/1,000 donors. Therefore, the overall positivity rate for T. cruzi in the donor pool was 484/1,000 in 2002. However, to match the donor pool for all diseases being tested, the calculations were done based on the number of donors who were tested for all infections (i.e., 5,353).

The second-generation reagents for HCV and the reagents for T. cruzi used for serologic screening in 1993 may have had lower sensitivity than those used in 1999–2002.911 On the other hand, screening for HIV and HBsAg was done, respectively, with third- and fourth-generation reagents during the overall period (1993–2002).911 To facilitate comparisons and to get more accurate prevalence data, it was assumed that the screening serology for HCV and for T. cruzi in 1993 were done with the reagents of higher sensitivity used in 1999–2002.

Tests for screening were considered to have the following sensitivity and specificity: HIV, third-generation EIA, a sensitivity of 99.99%, and a specificity of 99.90%1214; HBV (HBsAg), fourth-generation assay, a sensitivity and specificity of 99.90%12,15; HCV, third-generation EIA, a sensitivity and specificity of 98.52% and 99.40%, respectively.12,1619 For T.cruzi screening, it was considered that the EIA used had a sensitivity of 99.72% and a specificity of 98.82%.20 The reported prevalence rates for all serologic markers were adjusted to take into account an expected false-negative test (sensitivity < 100%) and false-positive result (specificity < 100%) for each particular test.1012 The multiplier correction factor for HIV prevalence was 0.991; for HCV was 1.098; and for T. cruzi was 1.001. Prevalence rates for HBV were not corrected given that estimates of false-positive and false-negative results were the same (0.1%).The prevalence of serologic markers for the non-screened population was expected to be equivalent to that reported for screened donors.911 The probability of receiving a potentially infected transfusion, P(R), in each year, was calculated by multiplying the prevalence or adjusted prevalence of a specific serologic marker by the proportion of unscreened donors (1 - screening coverage rate).2,911 The probability of acquiring a transfusion-transmitted infection, P(I), was calculated by multiplying the probability of receiving a potentially infected transfusion, P(R), by the infectivity rate.2,9,10 That is the likelihood of getting an infection when receiving an infected transfusion unit. This infectivity rate was estimated to be 90% for HIV,21 90% for HBV,22 90% for HCV,23 and 20% for T. cruzi.24 The infectivity rate of the latter in the South American endemic area has been reported higher and lower than 20% by different authors.3,2427

Nationwide in Bolivia, it was expected that every blood donation corresponded to a subsequent transfusion to one recipient in 1993, whereas 50% of the units from the whole country were reported to be fractionated in 2001 and 2002.28 In Santa Cruz, every blood donation corresponded to a subsequent transfusion to one recipient in 1993 and 1999. Seventy percent of the blood units obtained in Santa Cruz in 2000 and 2001 and 100% of those obtained in 2002 were fractionated. To facilitate comparisons, estimates of P(R) and P(I) were made without taking into account blood fractionation. The final calculations that were adjusted taken into account blood fractionation included 1) units not transfused because of screening (calculated by multiplying the total number of screened donors by the prevalence rate or the adjusted prevalence rate of the serologic markers); 2) infected units transfused (calculated by multiplying the total number of unscreened donors by the prevalence rate or adjusted prevalence rate of the serologic markers); 3) cases of infection prevented (calculated by multiplying the number infected units prevented of transfusion by the infectivity rate); and 4) cases of transfusion-transmitted infections [calculated by multiplying the number of donations in a given year by P(I) or by multiplying the number infected units transfused by the infectivity rate]. It was estimated that, when fractionation occurred, each original unit was given to only two recipients.

When donor screening was 100%, it was consider that transfusion-transmitted infections was nil because residual infectivity for lack of sensitivity of diagnostic reagents was not taken into account. Most data were rounded to the nearest hundredth of a unit using conventional methods.

RESULTS

Funding was contingent on the decision that only one public blood bank was going to function in the city. The investment to strengthen the Santa Cruz Regional blood bank was $1,108,000 between 1996 and 2002. Of said amount, 45% was provided by the Belgian Technical Cooperation and the Belgian Directorate General for Development Cooperation (both bilateral Belgian aid agencies); 2% by the National Center for Tropical Diseases (CENETROP), with funds also provided by the Belgian bilateral aid; and 6% by the Pan American Health Organization/World Health Organization (PAHO/WHO). The Bolivian Ministry of Health and the Santa Cruz Municipality provided 20% and 27% of the funding, respectively (Table 2). Starting in January 1999, screening coverage for HIV, HBV, HCV, and T. cruzi was 100%, with the exception of HCV, in which full screening coverage was achieved in September of that year.

The number of donors, percentage of donors screened, and prevalence rates (per 1,000 donors), are shown in Table 3, whereas the risk (per 10,000 donors) and the potential number of infections acquired through blood transfusion or prevented by screening are shown in Table 4. As expected, the estimated number of infections transmitted through blood transfusion for 1993 in Santa Cruz was higher than that estimated for 1999–2002.

The probability of getting an HIV-infected unit of blood or an infection in Santa Cruz was considered nil in 1999 and 2000, not only because of the 100% screening coverage for HIV but also because the prevalence of the infection was almost nil in the donor population. In 2001 and 2002, the HIV prevalence increased. It can be estimated that testing for HIV antibodies prevented transfusion of 32 infected units and 29 infections in those 2 years (Table 4). In 1993, lack of screening for HBV may have generated 35 units carrying the virus and 32 infections. In 1999, 100% screening coverage for HBV prevented the transfusion of 35 infected units of blood and 32 infections. With 100% screening, 196 HBV infected units were discarded, and 177 infections were prevented from 1999 and 2002 (Table 4). There is not a definite explanation for the wide variation of HCV prevalence in the various years. One possibility may be that the questionnaire implemented for screening donors before blood withdrawal was more effective some years that in others. Given that, in 1999, screening coverage for HCV was incomplete, it was estimated that nine units of blood from the Santa Cruz blood bank were infected with HCV, generating eight HCV infections that year. In any case, the screening prevented transfusion of 600 infected units of blood and 540 infections from 1999 through 2002 (Table 4).

Among the infections considered here, Chagas disease was the disease with the highest prevalence in Santa Cruz. Incomplete screening for T. cruzi in 1993 allowed that 4,568 units were tainted with T. cruzi. Screening in further years had the highest impact, preventing transfusion of 10,661 infected units and 2,133 infections from 1999 to 2002 (Table 4).

At the end of 2001 and 2002, the overall risk of acquiring any of the infectious diseases transmitted by blood was higher for the whole country than for the department of Santa Cruz in the same year (Table 4). Although in Santa Cruz it was estimated that no infected units were transfused in 2001 and 2002, it was estimated nationwide that 49 units tainted with HBV, 164 with HCV, and 824 with T. cruzi may have been transfused in those 2 years.

DISCUSSION

The numbers and rates mentioned above may be underestimated, for example, in the case of HBV, for which there was no screening for anticore antibodies. Moreover, no consideration was given to the potential risk of transmission of viral diseases during the window period, when antibodies are not detected, even with 100% screening.29,30 In the case of HIV, this is unlikely, because the overall number of donors in the Santa Cruz blood bank is relatively small and the prevalence is low. Another possibility of underestimation is the residual risk because the reagents sensitivity is not 100%.11

There is also a possibility that numbers may have been overestimated. It has already been shown that a variable number of those positive by screening for HIV were not confirmed with a second test; the same is true for HVB and HCV.31,32 Even if a very high sensitivity test for T. cruzi was used, a second assay would be necessary for confirmation. The use of a parallel test would increase the sensitivity of the diagnosis.33,34

The use of IHA to prescreen donors for T. cruzi to save money allowed the deferment of 1,649 donors in 2002. However, it also indicated the low sensitivity of the IHA reagent used to prescreen. In the context of Bolivia, despite of the low sensitivity of the IHA, savings were substantial.

The low sensitivity of the commercial IHA was not totally unexpected. Testing of commercial antigens in Chile had indicated that three of four commercial IHA reagents were not recommended because of their low sensitivity.35 Also in Chile, when an IHA and three different ELISA reagents were tested for routine serology screening in blood banks, the IHA was the least sensitive test.36 Testing of 11 IHA kits in Brazil showed that sensitivity varied from 44% to 100%, and only four kits did not give false-negative results.37 Prescreening with IHA is not part of the standard screening protocol for blood donors, and WHO recommends at least one test for blood donor screening, and that test should be an EIA.38

Strengthening of the Santa Cruz Blood Bank included all aspects that may influence safe blood; the excessive use of transfusions by health care providers in Santa Cruz39 requires limiting the number of transfusions, paid donors should be avoided, and donors must be submitted to a prescreen through a questionnaire. All of these items had been implemented: paid donors had been banned; the number of volunteer donors had increased from 1.1% in 1998 to 13.3% in 2001; and the rational use of blood through training of physicians was strongly promoted.40 Fractionation of blood (100% in 2002) and improvements on the rational use of blood may explain the lower number of donors being used in 2002 compared with 1993. Nevertheless, testing for specific antibodies is the ultimate measure to prevent blood-borne diseases. Considering the overall investment made from 1996–2002 (i.e., US$1,108,000), the number of infected units detected and discarded (11,489) and the potential infections prevented (2,879) in 4 years of operations of the Santa Cruz blood bank, it was estimated that the cost of discarding one infected unit carrying any infection was $96 (total investment/ number of units discarded) and for preventing one infection was $385 (total investment/number of potential infections prevented).

Although the use of secondary data for public health policy decisions has some limitations, this report shows the importance of having launched adequate blood banking services for preventing transmission of blood-borne diseases in Bolivia through a multi-pronged effort that included local and national authorities, as well as bilateral and international cooperation agencies. These efforts were successful under a specific set of circumstances that included bilateral aid from Belgium, support from the America’s Regional Office of the WHO and of local partners, and a context of broad support for initiatives in the Southern Cone of South America to interrupt transmission of T. cruzi by blood transfusion41 and to strengthen transfusional medicine in Latin America and the Caribbean.42 The achievements are being sustained, and we expect this model might be used in other countries worldwide.

Table 1

Sources of information and assumptions

YearBoliviaSanta Cruz
1993Information on number of donors, percent of donors screened, and prevalence of serologic markers was obtained from the Ministry of Health.2 At that time, however, the nationwide prevalence for HCV in blood donors was unknown. Therefore, it was assumed to be the same as the one in Santa Cruz in 1992.7Information on number of donors, percent of donors screened, and prevalence of serologic markers from official sources did not exist. Numbers from other sources were used for the calculations.
 Number of donors, 13,708 as reported for Santa Cruz in 1993.7
 The percent of donors screened was similar to that found nationwide in 1993: 36% for HIV; 15.0% for HBV; nil for HCV, and 29% for T. cruzi.2
 The HIV prevalence was assumed to be 0; HBV, 3/1,000; and T. cruzi, 471.5/1,000, the same as that reported for Santa Cruz in 1994.
 The prevalence assumed for HCV in 1993, 5/1,000 HIV, was the same as that reported for Santa Cruz in 1992.7
1999Available information not usedInformation on number of donors, percent of donors screened, and prevalence of serologic markers from Santa Cruz blood bank records.
2000Information not availableInformation on number of donors, percent of donors screened, and prevalence of serologic markers from Santa Cruz blood bank records.
2001Information on number of donors, percent of donors screened, and prevalence of serologic markers from Ministry of Health.8Information on number of donors, percent of donors screened, and prevalence of serologic markers from Santa Cruz blood bank records.
2002The number of donors and percent of donors screened were obtained from the Ministry of Health for 2002,8 but the prevalence of serologic markers was not reported that year. Therefore, the prevalence per 1,000 donors assumed for the calculations for 2002 were those reported by the Ministry of Health for 2003: 1.0 for HIV, 3.8 for HBV, 8.9 for HCV, and 76.5 for T. cruzi.8Information on number of donors, percent of donors screened, and prevalence of serologic markers from Santa Cruz blood bank records.
Table 2

Source and amount of funding (US $) for the Santa Cruz blood bank between 1996 and 2002

Source of funding1996199719981999200020012002
* Equipment, reagents, personnel training, and salaries.
† Reagents and materials for implementing quality assurance.
‡ Consultants for onsite training, onsite external evaluations, development of operational manuals, fellowships abroad, and for promotional activities.
§ Personnel salaries, basic services (electricity, water, gas, telephone), and reagents.
¶ Building improvements.
Belgium Technical Cooperation*503,000
CENETROP†25,00000
PAHO/WHO‡65,00000
Ministry of Health§0043,00043,00043,00043,00043,000
Municipality of Santa Cruz¶0015,00015,00015,00015,00015,000
110,00000
Municipality of Santa Cruz§0023,00023,00023,00023,00023,000
Table 3

Number of donors, prevalence of serologic markers for infectious diseases, and percentage of donors screened in Bolivia as a whole and the Department of Santa Cruz, 1993–2002

BoliviaSanta Cruz
HIVHBVHCVT. cruziHIVHBVHCVT. cruzi
YearNo. donorsPrevS CoPrevS CoPrevS CoPrevS CoNo. donorsPrevS CoPrevS CoPrevS CoPrevS Co
* Santa Cruz blood bank records.
Prev = prevalence (per 1,000); S Co = screening coverage: percent of donors screened.
Blank cells: information not used or not available.
199337,94820.123622.021525.0702148.0229213,7087073623.071525.0702471.57292
19994,185*01008.41003.032500.5100
20004,142*01007.810021.7100343.3100
200124,747110.4865.7842.84999.1865,588*1.21005.31009.8100280.3100
200224,64981.0983.8908.97176.5895,353*1.91005.210027.8100324.7100
Table 4

Risk of receiving and infected transfusion or an infection, number of infected units not transfused or used in a transfusion, and number of blood-borne infections prevented or transmitted infections, 1993–2002

HIVHBVHCVT. cruzi
YearP (R)P (I)IUN TrIU TrC PrevTTIP (R)P (I)IUNTrIU TrC PrevTTIP (R)P (I)IUNTrIU TrC PrevTTIP (R)P (I)IUN TrIU TrC PrevTTI
P (R) = probability of receiving an infected transfusion per 10,000 transfusions; P (I) = probability of getting a transfusion-transmitted infection per 10,000 transfusions; IUN Tr = number of infected units not transfused because of screening; IU Tr = number of infected units transfused; C Prev = number of cases of infection prevented; TTI = number of transfusion-transmitted infections.
Bolivia
    19931112121715116510585549020801881,0452091,6523,966330793
    200111141131981773416030161455595053138283,171512634102
    20020036032044126151141328252561052319484172,52031250563
Santa Cruz
    19930.00.00000262363553255490750683,3326661,9024,568380914
    19990.00.000000035032023204948002,09704190
    20000.00.00000005404900016801510002,41904840
    20010.00.012011000510460001020920002,66505340
    20020.00.0200180005605000032602930003,48006960

*

Address correspondence to Gabriel A. Schmunis, 4256 Warren Street NW, Washington, DC 20016. E-mail: gabriel.schmunis@gmail.com

Authors’ address: Gabriel Adrián Schmunis, Communicable Diseases Unit Pan American Health Organization/World Health Organization, 525 23rd St., NW, Washington, DC 20037, Tel: 1-202-974-3272, Fax: 1-202-974-3688. Gloria Rodriguez, Banco Regional de Santa Cruz Santa Cruz, Bolivia, Tel/Fax: 591-3333-2070, E-mail: glorihemato@hotmail.com. Jan Coenen, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium, Tel: 32-03-2476237, E-mail: jcoenen@itg.be. Enrique Gil Bellorin, Oficina Sanitaria Panamericana Edificio ETISA, Plazuela España 7 ma Avda 12–23, Zona 9 Ciudad de Guatemala, Guatemala, E-mail: gilenriq@gut.ops-oms.org. Alberto Gianella, Centro Nacional de Enfer-medades Tropicales Casilla de Correo, 2974 Santa Cruz, Bolivia, Tel: 591-3354-2006, E-mails: algianella@gmail.com or algianella@cotas.com.bo.

Acknowledgments: The authors thank Roxane Salvatierra for editing the manuscript.

REFERENCES

  • 1

    Linares L, Vinelli E, eds., 1994. Taller Latinoamericano de Servicios de Transfusión Sanguínea y óptimo uso de los Recursos. Caracas, Venezuela: Cruz Roja Finlandesa.

  • 2

    Schmunis GA, Zicker F, Pinheiro F, Brandling-Bennett D, 1998. Risk of transfusion transmitted infectious diseases in Central and South America. Emerg Infect Dis 4 :5–11.

    • Search Google Scholar
    • Export Citation
  • 3

    Zuna H, La Fuente C, Valdez E, Recacochea M, Franco JL, Romero A, Bermudez H, 1985. Estudio prospectivo de la transmisión del Tripanosoma cruzi por vía sanguínea en Bolivia. Ann Soc Belg Med Trop 65 (Suppl. 1):107–113.

    • Search Google Scholar
    • Export Citation
  • 4

    Carrasco R, Miguez H, Camacho C, Echalar L, Revollo S, Ampuero T, Dedet JP, 1990. Prevalence of Trypanosoma cruzi infection in blood banks of seven departments of Bolivia. Mem Inst Oswaldo Cruz 85 :69–73.

    • Search Google Scholar
    • Export Citation
  • 5

    Landivar WHC, Nakasa T, Tachibana H, Paz KC, Tateno S, 1992. Seropositivity to Tryapanososma cruzi in blood donors in Santa Cruz, Bolivia. JID 166 :1464–1465.

    • Search Google Scholar
    • Export Citation
  • 6

    Zuna H, Gianella A, 1991. 92/93. Infeccion por T. cruzi en donantes de sangre en Santa Cruz, Bolivia: (Influencia de la migracion). Bol Cient Centro Nacional de Enfermedades Tropicales 15 :60–64.

    • Search Google Scholar
    • Export Citation
  • 7

    Miyoshi C, 1995. The cost effectiveness of blood donor screening programs to identify transfusion transmitted Chagas disease in Bolivia, including the use of a natural history model of Chagas’ disease. Takemi Program in International Health, Harvard School of Public Health.

  • 8

    Pan American Health Organization, 2005. Transfusion Medicine in the Caribbean and Latin American Countries, 2000–2003. Washington, DC: Pan American Health Organization.

  • 9

    Schmunis GA, Zicker F, Segura EL, Del Pozo AE, 2000. Transfusion-transmitted infectious diseases in Argentina, 1995 through 1997. Transfusion 40 :1048–1053.

    • Search Google Scholar
    • Export Citation
  • 10

    Schmunis GA, Zicker F, Pinheiro F, Cruz JR, Cuchi P, 1991. Safety of blood supply for infectious diseases in Latin American countries, 1994–1997. Am J Trop Med Hyg 65 :924–930.

    • Search Google Scholar
    • Export Citation
  • 11

    Schmunis GA, Cruz JR, 2005. Safety of the blood supply in Latin America. Clin Microbiol Rev 18 :12–29.

  • 12

    United States General Accounting Office, 1997. Report to the Ranking Minority Member Committee on Commerce, House of Representatives. Blood Supply. FDA Oversight and Remaining Issues of Safety. GAO/PEMED-97-1. Washington, DC: United States General Accounting Office.

  • 13

    WHO/UNAIDS, 1998. Operational Characteristics of Commercially Available Assays to Determine Antibodies to HIV-1 and/ or HIV- 2 in Human Sera. Report 9–10. Geneva: World Health Organization.

  • 14

    WHO/UNAIDS, 1999. Operational Characteristics of Commercially Available Assays to Determine Antibodies to HIV-1 and/ or HIV-2 in Human Sera. Report 11. Geneva: World Health Organization.

  • 15

    World Health Organization, 2001. Hepatitis B Surface Antigen Assays: Operational Characteristics. Report 1. Geneva: World Health Organization.

  • 16

    Couruce AM, Le Marrec N, Girault A, Ducamp S, Simon N, 1994. Anti-hepatitis C virus (anti-HCV) seroconversion in patients undergoing hemodialisis: comparison of second- and third-generation anti-HCV assays. Transfusion 34 :790–795.

    • Search Google Scholar
    • Export Citation
  • 17

    Uttendaelle S, Claeys H, Mertens W, Verhaert H, Vermylen C, 1994. Evaluation of third generation screening and confirmatory assays for HCV antibodies. Vox Sang 66 :122–129.

    • Search Google Scholar
    • Export Citation
  • 18

    Vrielink H, Reesink PJ, van den Burg PJM, Zaaijer HI, Cuypers HTM, Lelie PN, van der Poel CL, 1997. Performance of three generations of anti-hepatitis C virus enzyme-linked immuno-absorbent assays in donors and patients. Transfusion 37 :845–849.

    • Search Google Scholar
    • Export Citation
  • 19

    World Health Organization, 2001. Hepatitis C Assays: Operational Characteristics (Phase 1). Report 2. Geneva: World Health Organization.

  • 20

    Qelemann WM, Teixeira MD, Verissimo da Costa GC, Borges-Pereira J, De Castro JDF, Coura JR, Peraltan JM, 1998. Evaluation of three commercial enzyme-linked immuno-sorbent assays for diagnosis of Chagas disease. J Clin Microbiol 36 :2423–2427.

    • Search Google Scholar
    • Export Citation
  • 21

    Donegan E, Stuart M, Niland JC, Sacks HS, Azen SP, Dietrich SL, Faucett C, Fletcher MA, Kleiman SH, Operskalski EA, 1990. Infection with human immunodeficiency virus type 1 (HIV-1) among recipients of antibody-positive blood donations. Intern Med 113 :733–739.

    • Search Google Scholar
    • Export Citation
  • 22

    Schreiber GB, Busch MP, Kleinman SH, Korelitz JJ, 1996. The risk of transfusion-transmitted viral infections. N Engl J Med 334 :1685–1690.

    • Search Google Scholar
    • Export Citation
  • 23

    Aach RD, Stevens CE, Hollinger FB, Mosley JW, Petersen DA, Taylor PE, Johnson RG, Barbosa LH, Nemo GJ, 1991. Hepatitis C virus infection in post-transfusion hepatitis. An analysis with first-and second-generation assays. N Engl J Med 325 :1325–1329.

    • Search Google Scholar
    • Export Citation
  • 24

    World Health Organization, 1991. Control of Chagas disease. WHO Tech Rep Ser No. 811 :32.

  • 25

    Cerisola JA, Rabinovich A, Álvarez M, Di Corleto CA, Pruneda J, 1972. Enfermedad de Chagas y la transfusión de sangre. Bol. Ofic Sanit. Panam. 73 :203–221.

    • Search Google Scholar
    • Export Citation
  • 26

    Attias A, Lorca M, Canales M, Mercado R, Reyes V, Child R, 1984. Chagas disease: transmission by blood transfusion in Chile. Bol Hosp San Juan de Dios (Santiago) 31 :301–306.

    • Search Google Scholar
    • Export Citation
  • 27

    Lorca M, Lorca J, Child R, Attias A, Canales M, Lorca E, Gutiérrez J, 1988. Prevalencía de la infección por Trypanososma cruzi en pacientes politransfundidos. Rev Med Chil 116 :112–116.

    • Search Google Scholar
    • Export Citation
  • 28

    Organización Panamericana de la Salud, 2003. Medicina Transfusional en América Latina 1994–2003. Document OPS/EV-LAB/01.2003. Washington, DC: OPS.

  • 29

    Lackritz EM, Satten GA, Aberle-Grasse J, Dodd RY, Raimondi VP, Janssen RS, Lewis WF, Notari EPI, 1995. Estimated risk of transmission of the human immunodeficiency virus by screened blood in the United States. N Engl J Med 333 :1721–1725.

    • Search Google Scholar
    • Export Citation
  • 30

    Schreiber GB, Busch MP, Kleinman SH, Korelitz JJ, 1996. The risk of transfusion-transmitted viral infections. N Engl J Med 334 :1685–1690.

    • Search Google Scholar
    • Export Citation
  • 31

    Ministerio de Sanidad y Consumo, Direccion General de Salud Publica. Plan Nacional de Hemoterapia, 1998. Estadistica Estatal de Centros de Transfusion y Bancos de Sangre. Año 1997.

  • 32

    Sookvian S, Castano G, Castiglioni T, Pilar S, Videz P, Gonzalez J, Frider B, 1997. Problematica de la infeccion por el virus de la hepatitis C en donantes de sangre. Medicina (Buenos Aires) 55 :699–707.

    • Search Google Scholar
    • Export Citation
  • 33

    Wendell S, Gonzaga A, 1993. Chagas’ disease and blood transfusion: a new world problem? Vox Sang 54 :1–12.

  • 34

    Salles N, Sabino EC, Cliquet MG, Eluf-Neto J, Mayer A, Almeida-Neto AC, Mendonca MC, Dorliach-Llacer P, Chamone DF, Saez-Alquezar A, 1996. Risk of exposure to Chagas disease among seroreactive Brazilian blood donors. Transfusion 36 :969–973.

    • Search Google Scholar
    • Export Citation
  • 35

    Lorca M, Child R, Garcia A, Silva M, Osorio J, Atlas A, 1992. Evaluacion de reactivos comerciales empleados en el diagnosticode la enfermedad de Chagas en bancos de sangre de Chile. I. Selección de reactivos. Rev Med Chile 120 :420–426.

    • Search Google Scholar
    • Export Citation
  • 36

    Lorca MH, Child RB, Garcia CA, Silva MG, Martinez LP, Jerez JM, Toledo ID, Mezzano DA, 1994. Evaluacion de reactivos comerciales empleados en el diagnostico de la enfermedad de Chagas en bancos de sangre de Chile. II Aplicación rutinaria. Rev Med Chile 122 :925–931.

    • Search Google Scholar
    • Export Citation
  • 37

    Saez-Alquezar A, Luquetti AO, Borges Pereira J, Furtao EM, Gadelha MFS, Garcia-Zapata MT, Arruda AHS, 1997. Estudo multicentrico: avaliacao do desempenho de conjuntos diagnosticos de hemaglutinacao indireta, disponiveis no Brasil, para o diagnostico sorologico da infeccao pelo Trypanosoma cruzi.Rev Patol Trop. 26 :343–374.

    • Search Google Scholar
    • Export Citation
  • 38

    World Health Organization, 2002. Control of Chagas disease. Geneva: World Health Organization.

  • 39

    Zuna H, Gianella A, 1991. 92/93. Enfermedad de Chagas en donantes de sangre en Santa Cruz de la Sierra. Bol Cient CENETROP 15 :65–69.

  • 40

    Bossuyt M, Torrez R, Coenen J, Herteleer J, 2002. Banco de Sangre Regional—Santa Cruz 1994–2002. Informe Final. Brussels, Belgium: Projecto Sistemas Locales de Salud Santa Cruz, Cooperacion Tecnica Belga.

  • 41

    Pinto Diaz JC, 2007. Southern Cone initiative for the elimination of domestic populations of Triatoma infestans and the interruption of transfusional Chagas disease. Historical aspects, present situation, and perspectives. Mem Inst Oswaldo Cruz 102 (Suppl. 1):11–18.

    • Search Google Scholar
    • Export Citation
  • 42

    Pan American Health Organization, 1999. Strengthening blood banks in the Region of the Americas. 124th Session of the Executive Committee. Resolution CD41 :R15.

    • Search Google Scholar
    • Export Citation

Author Notes

Reprint requests: Enrique Gil Bellorin, Oficina Sanitaria Panamericana. Ancon, Avenida Gorgas, Edificio 261, 2do piso, Casilla Postal 0843-03441, Ciudad de Panama, Panama, E-mail: gilenriq@pan.
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