Journal of Hepatology
Volume 45, Issue 4 , Pages 607-616, October 2006

Transmission of hepatitis C virus by blood transfusions and other medical procedures: A global review

  • Daniele Prati

      Affiliations

    • Corresponding Author InformationTel.: +39 339 1022840/+39 0341 489872; fax: +39 0341 489871.

Department of Transfusion Medicine and Hematology, Ospedale Alessandro Manzoni, Lecco, Italy Postgraduate School of Gastroenterology, University of Milan, Italy

published online 25 July 2006.

Article Outline

Hepatitis C virus (HCV) is a leading cause of chronic blood-borne infection and chronic liver disease. The global epidemic of HCV infection emerged in the second half of the 20th century, and several lines of evidence indicate that it was primarily triggered and fed iatrogenically by the increasing use of parenteral therapies and blood transfusion. In developed countries, the rapid improvement of healthcare conditions and the introduction of anti-HCV screening for blood donors have led to a sharp decrease in the incidence of iatrogenic hepatitis C, but the epidemic continues to spread in developing countries, where the virus is still transmitted through unscreened blood transfusions and non-sterile injections.

This article reviews the published literature concerning HCV transmission through blood transfusions and other unsafe medical procedures. Given the substantial difference in current disease transmission patterns between the northern and southern hemispheres, the situation in developed and developing countries is separately analysed.

Abbreviations: HCV, hepatitis C virus, HIV, human immunodeficiency virus, HBV, hepatitis B virus, NAT, nucleic acid technology, HDI, human development index, IVDU, intravenous drug use

 

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1. Search methods 

The information in this report is primarily based on peer-reviewed medical articles published up to 15 April 2006. A PubMed search for appropriate articles was made using the terms “hepatitis C” or “HCV” in combination with the roots “iatrogen*, “nosocom*, and “transfus*”. The search was not restricted by language. Up-to-date reviews and highly regarded older papers were also selected. The bibliographies of the articles on hand were used to find other references.

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2. Social and historical background 

As pointed out by Stephen S. Morse, the history of infectious diseases has largely been a history of microbes that have taken advantage of the rich opportunities we offered them to thrive, prosper and proliferate [1]. The global epidemic of HCV illustrates this very well: the rapid spread and worldwide dissemination of HCV arises from its efficient transmission through transfusions of blood and blood products, parenteral therapies, and the other invasive medical procedures that became increasingly available during the 20th century.

Massive and unsafe injection campaigns were started between the two World Wars, when glass syringes and other medical devices began to be produced on a large scale. Between 1920 and 1950, the unit price per syringe decreased by 80%, and global production increased more than 100-fold. Injections were synonymous with effective treatments, as they were used for vaccination or prophylaxis campaigns, the administration of antibiotics, and insulin treatments [2]. Furthermore, during and immediately after World War II, blood transfusion became a common clinical practice, and fractionated blood derivatives started to be produced and administered [3].

However, poorly sterilised syringes and unscreened blood and blood products were excellent vectors for the transmission of infectious diseases. Some research groups, using sophisticated epidemiological and molecular evolutionary approaches, have shown that the emergence of the major HCV subtypes in different countries largely coincides with local outbreaks of unsafe parenteral treatments (see summary in Table 1) [4], [5], [6], [7], [8], [9], [10]. Parenteral antischistosomal therapy with antimony was responsible for the dissemination of HCV among the general populations in Japan and Egypt; the epidemic in Egypt actually continued until 1986 (when oral medicine was introduced to take over the treatment of schistosomiasis), and caused the highest national prevalence of anti-HCV in the world (25%) [4], [5], [6], [11].

Table 1. Summary of studies that have used epidemiological and molecular evolutionary approaches to trace the patterns of HCV transmission in different countries
CountryHCV subtype(s)Estimated year of first appearance of HCVEstimated year of start of major HCV outbreak(s)Main social and historical events associated with the start of HCV outbreak(s)References
Egypt4a19021930sParenteral antischistosomal therapy campaign[4], [5], [6]
Japan1b (1st wave)18121920Parenteral antischistosomal therapy campaign[5], [6], [7], [8]
Japan1b (2nd wave)19181940sWorld War II[5]
Spain1b1892Late 1930sSpanish Civil War[5]
FranceN.R.N.R.1940sWorld War II[9]
Former Soviet Union3a19581960sUnsafe measles vaccination campaigns – increasing IVDU[5]
USA1a,1b19201960sIncreasing IVDU (predominant) and unscreened blood transfusions[5], [8]
China1b19661970sChinese Cultural Revolution; increasing blood transfusion and other invasive treatments[10]
South Africa5a1937Late 1950sIncreasing use of unsafe medical procedures[5]
Vietnam1a1920Late 1960sVietnam War[8]

HCV, hepatitis C virus; IVDU, intravenous drug use.

A number of other local epidemics were probably triggered and possibly magnified by the increasing use of unsafe medical procedures, particularly at the time of military conflicts. In particular, blood transfusions were a leading cause of viral spread: by the end of the 1980s, one in 50 blood units in developed countries transmitted hepatitis C [12], [13]. As a result, most chronic transfusion recipients and virtually all patients receiving clotting factor concentrates developed chronic hepatitis [14], [15], [16]. However, the incidence of HCV infection in resource-rich countries greatly decreased within a few years because of improved infection control standards, the implementation of effective virus-inactivation procedures for blood derivatives (1987), and the introduction of second-generation anti-HCV tests for blood donors (1992) [17], [18], [19]. The majority of new HCV infections in these countries are now due to needle sharing by intravenous drug abusers [17].

However, and in sharp contrast, the iatrogenic epidemic of hepatitis is still continuing in the poor regions of the world, as is extensively discussed below.

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3. Transmission of HCV by blood transfusion 

3.1. Developed countries 

Clinicians in developed countries are now facing the long-term effects of the past epidemics of transfusion-associated hepatitis C. Adult cohort studies have shown that, an average of 15 years after blood transfusion, approximately 75% of the patients are positive for HCV RNA and the frequency of liver cirrhosis is 15–20%, although more favorable outcomes have been observed in children and young women [15], [20], [21], [22], [23], [24], [25], [26].

However, blood supplies are now very safe. As extensively reviewed elsewhere, there have been no cases of HCV transmission due to the administration of blood derivatives since 1994 [15], [27], [28]. In terms of labile blood components, it has also been shown that the majority of the hepatitis cases currently occurring in blood recipients are not caused by blood transfusions, but may be due to nosocomial transmission [29], [30]. Since the introduction of blood donor anti-HCV screening, the residual risk is essentially limited to the units collected during the donors’ serological window period [31], and has become so small that it cannot be accurately measured by traditional approaches (i.e. prospective surveys of blood recipients) because of the limited number of documented transmission events. It can therefore only be predicted by means of indirect measures, such as mathematical models involving the incidence of infection and the duration of the pre-seroconversion window period [32]. As of the year 2000, the estimates were about 1:200,000 blood units or less [15], [33], [34], which means that the possibility of receiving an HCV-infected transfusion was substantially lower than that of dying after a percutaneous liver biopsy (1:10,000–12,000) [35] and comparable with that of dying while playing football (1:150,000) [36].

In this context, it was predictable that the implementation of new screening measures would have minimal (if any) effect on overall patient safety. However, in an attempt to respond to media and public pressure for “zero risk” after the shockwave of the human immunodeficiency virus (HIV) transfusion epidemic [33], [37], most governments decided that it was necessary to add the determination of HCV RNA by nucleic acid technology (HCV-NAT) to the battery of tests already in use. In order to limit costs, HCV-NAT is generally performed on plasma mini-pools of different blood donations [38], [39].

Now, 3–6 years after the widespread implementation of HCV-NAT, it is possible to make a provisional assessment of its effectiveness. The residual risk of acquiring hepatitis C through blood transfusions has further decreased, and the current risk estimates per million donations are approximately 0.52 in the USA [40], 0.70 in Canada [41], and 0.1–2.33 in different European countries [42], [43], [44], [45], [46], [47], [48]. Sporadic cases of transmission may still occur because recently infected donors may have blood HCV levels below the detection limit [49], [50], but there is a trend towards a continuing decrease in risk over time probably because of the measures taken to prevent the spread of blood-borne infections in the general population and the improvement in donor selection criteria [48]. However, it must be borne in mind that HCV-NAT cannot replace serological screening, because molecular techniques alone may fail to identify potentially infectious blood donations [51].

The overall contribution of HCV-NAT toward reducing the risk of transfusion transmitted hepatitis is marginal, and less than expected in most countries. Of the 58 million donations collected in 14 European countries between 2001 and 2003, only 54 were HCV RNA positive/anti-HCV negative, a screening yield of 0.93 per million donations [39]. The yield was slightly better in North America (3.92 per million), the Pacific Area (2.37) [39] and in Japan (2.98) [52]. With the sole exception of the USA, there were fewer isolated HCV RNA positive donations than expected throughout the world [39]. From a clinical and epidemiological standpoint, it is clear that the identification of a few window period donations per year will minimally affect the overall burden of liver disease. For example in Italy – where the yield is 1.79 per million units, higher than in other European countries – HCV-NAT can reasonably be expected to prevent approximately only 40 window-period donations over 10 years. Given short-term mortality due to unrelated causes in transfused patients [53] and the data on infection outcome [54], only about five future cases of end-stage liver disease will probably be avoided (Fig. 1). Furthermore, this small increase in safety with regard to HCV transmission will be very expensive, because the cost of HCV-NAT in Italy during the same period will be approximately € 140 million (i.e. € 6 per 2.3 million units per year), with most of the excess costs related to the NAT screening of blood components being due to royalties paid to the companies that hold the patents for the tests [55]. Several estimates indicate that the cost efficiency of NAT is up to 1000 times less than that of standard medical interventions [55], [56], [57], and this may have broader detrimental effects on health safety. In a recent review [57], Sullivan used the economic law of diminishing return to illustrate how such incremental costs may ultimately threaten overall patient care because of the diversion of finite healthcare resources away from higher priority needs.

  • View full-size image.
  • Fig. 1. 

    Projected clinical yield of 10 years of HCV-NAT application in Italy. Approximate estimates computed on the basis of the number of HCV RNA+/anti-HCV-blood donations detected per year [39], average mortality rate among blood recipients [53], and current data on hepatitis C outcome [54]. HCC, hepatocellular carcinoma.

However, despite this evidence, it is unlikely that HCV-NAT will be discontinued for a number of reasons. First of all, the legal interpretation of the precautionary principle that “it is better to be safe than sorry” implies that governments must adopt all possible measures to increase blood safety, regardless of the entity of the risk, and any failure to do so would leave them at fault and liable for damages [33], [37]. As recently pointed out, the political regulators who set the standards are not responsible for the cost consequences in other areas of healthcare [57]. Second, the use of NAT-based technology in blood services has proved to be useful in setting up new tests for the screening of emerging pathogens [58]. And finally, the interests of the industry in the continuing use of highly remunerative tests cannot be denied [55]. However, any future decisions concerning the implementation of new molecular tests for blood screening purposes (such as the shift from mini-pool to single-unit HCV-NAT testing and/or the introduction of NAT for hepatitis B virus (HBV) testing) should be based on evidence rather than prudence alone.

3.2. Developing countries 

The picture is very different in developing countries, where blood transfusions remain a major cause of the spread of HCV. In the period 2001–2002, more than six million blood units were not screened for major blood-borne infections, including HCV [59]. Although this number was considerably less than during the biennium 1998–1999 [60], this reduction cannot be considered sufficient to limit the continuing HCV epidemic.

Developing nations largely fail to meet the key requirements for a modern blood transfusion system: i.e. the collection of a safe and locally sufficient blood supply from non-remunerated donors within a formal organisational and legislative framework [59]. The underlying problems are structural and attributable to various causes. Blood safety is threatened by a combination of factors due to poverty, including a lack of infrastructures, frequent electricity breakdowns, the unavailability of properly trained professionals, an inadequate supply of instruments and laboratory reagents, and difficulties in mobilising volunteer donors [17], [59], [60], [61], [62], [63], [64].

Most of what we know about the status of transfusion medicine in developing countries comes from the surveys that the World Health Organization (WHO) has carried out in cooperation with national governments since 1998. The Global Database on Blood Safety (GDBS) has been very recently updated with the 2001–2002 data collected in 178 of the 191 Member States of the WHO, representing 95% of the world’s population [59], and the publication of a new report (2004) is expected for the second half of this year [Ms Jan Fordham, WHO; personal communication]. The GDBS survey groups countries according to the Human Development Index, which ranks the average human development in each country on the basis of life expectancy, literacy, and gross domestic product. As summarised in Table 2, there are enormous between-country disparities with regard to access to safe blood transfusions, which are largely related to their degree of socio-economic development. Of the 81 million units of blood and 20 million litres of plasma donated annually throughout the world, approximately 60% are collected and used in rich countries, where less than 20% of the world’s population lives.

Table 2. Characteristics of the blood transfusion system and indicators of blood transfusion safety in the 178 countries participating in the Global Database on Blood Safety (2001–2002), grouped according to the Human Development Index [59]
Human Development Index (HDI)
LowMediumHigh
No. of countries (%)36 (20)88 (50)54 (30)
Percentage of world population117118
No. of units donated per year, in millions (%)2.3 (3)29.4 (36)49.4 (61)
Litres of plasma designated for fractionation, in millions0.034.415.7
Estimated blood donation rates, per 1000 inhabitants3.310.640.0
Blood donor system
• Voluntary donors (%)346094
• Paid donors (%)63364
• Replacement donors (%)342
Anti-HCV screening
• Units screened for anti-HCV (%)51.396.399.9
• Prevalence of anti-HCV in repeat donors (%)1.540.210.007
• Prevalence of anti-HCV in first time donors (%)3.891.490.21

The countries were classified as having a low (<0.500), medium (0.500–0.799) or high HDI (⩽0.800) HDI on the basis of life expectancy, educational attainment, and adjusted income. High HDIs indicate developed countries; low and medium HDIs indicate developing countries [59]. 95% CI, 95% confidence interval, HCV, hepatitis C virus.

The current data indicate that 31 of the 142 “developing” countries do not undertake any anti-HCV screening, and another 37 screen less than 100% of blood units. Most of these countries are in Asia and Africa. For example, in Pakistan, where the rates of new HCV infections and liver related deaths are increasing exponentially [66], anti-HCV screening is used by only 23% of the blood banks [67]. A survey of Indian blood bank directors carried out in 2000 showed that 87% of centres screen for hepatitis B virus and 95% for HIV, but only 6% screen for HCV [68]. In Sub-Saharan Africa, only South Africa and Zimbabwe consistently test donors for anti-HCV [69]. Furthermore, in some developing countries, financial constraints mean that formally mandatory anti-HCV screening is not performed at all [17] or only if the patient is willing (and able) to pay [64]. Relatively better conditions are reported in Latin America and in the Caribbean, where 28 of the 38 countries participating in two recent surveys of the Pan-American Health Organisation [70], [71] ensure 100% coverage of anti-HCV screening.

Another difference in comparison with wealthy regions, where blood transfusions are mainly administered to elderly patients, is that the subjects who are those most exposed to blood transfusion and its risks are young women and children. Of the 150,000 women who die each year from blood loss due to pregnancy-associated causes, 99% live in the poor regions of the world [64], [72]. Furthermore, up to 70% of the blood transfusions administered in Africa are given to children suffering from malaria [72]. It is expected that the young age of the patients being infected as a result of blood transfusions will have a major impact in maintaining high prevalence rates and disease burdens in the general population, and may amplify the spread of HCV by non-iatrogenic (i.e. sexual and vertical) routes.

The frequency of anti-HCV seropositivity in blood donors is generally higher than in developed nations, even considering that figures are usually given as reactive rate (not even repeat reactive) and without confirmation [73]. Prevalence is destined to increase further unless there is a radical improvement in local infection control measures capable of limiting viral spread among the general population. Seropositivity rates are particularly high among blood donors in Pakistan (up to 21%) [67], Georgia (7.8%) [74], Burundi (4.9%), Cameroon (up to 8.7%), Tanzania (8%) and the Central African Republic (6.1%) [69], whereas relatively lower figures are reported in Latin America (0.1–1.1%) [71] and the Caribbean (0.7–1.9%) [70]. There are also some concerns about the reliability of serological testing: according to some reports, antibody tests for HCV genotypes and subtypes common in Europe and USA might not perform so well with African sera [69], [73]. In Ecuador, laboratories using rapid tests and certain lots of an enzyme-linked immunosorbent assay (ELISA) failed to detect HCV reactive sera [75], and studies from China indicate that approximately 1% of seronegative blood units test positive for HCV RNA by RT-PCR [65]. This suggests that, even when anti-HCV screening is performed, the residual risk of becoming infected can be much higher than in industrialised regions.

The recruitment of altruistic volunteer donors is especially difficult in developing countries not only because of the lack of resources and organisation, but also because of the presence of traditional beliefs and practices. Traditional Chinese culture holds that blood loss is detrimental to health, and the donation of blood is sometimes even seen as an act of disloyalty towards the donor’s ancestors [65]. In Africa, it is commonly believed that men can become impotent if they donate blood, or that infectious diseases can be caught from a donation needle [57]. The shortage of volunteers also means that many governments still allow donors to be paid, a practice that has proved to be risky in itself [57], and questions about high-risk behaviours are seldom asked [64]. In addition to improving the anti-HCV testing of voluntary blood donations, the other key areas for increasing transfusion safety are hemovigilance and the implementation of management systems designed to improve organisation, professional training, and the appropriate use of blood [57], [59].

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4. Transmission of HCV by other medical and surgical procedures 

4.1. Developed countries 

The healthcare environment is far from being free of risk. Even in countries who have adopted high sanitary standards, patients may still acquire HCV infection from other patients or infected healthcare providers.

The transmission of HCV in the setting of hemodialysis deserves special emphasis. Cases of viral hepatitis due to breaks in infection control techniques have been described among dialysed patients since the late 1960s [76]. When anti-HCV testing became available, it was observed that the prevalence of HCV in patients on dialysis varied greatly by geographic area (between 4% and 59% in different countries), and also within the same region (between 5% and 44% in different US centres) [77]. The factors that were constantly reported as being associated with an increased prevalence of HCV infection were the length of time on dialysis and the number of blood transfusions [76], [77]. The introduction of anti-HCV blood donor testing and the use of erythropoietin to reduce transfusion requirements has not abolished infection, but its rate of occurrence has progressively decreased [78], [79]. The DOPPS study [80] involved 8615 patients prospectively followed up in 308 facilities in seven countries between 1997 and 2001, and found a median HCV prevalence of 14% (range 2.6–22.9% in different countries), and median seroconversion rates of 2.5 per 100 person/years (range 1.2–3.9%) (Table 3). It also showed that the spread of HCV was associated with insufficient staff training and a higher baseline prevalence of infection in the facility. Similarly, in a recent HCV outbreak involving 22 patients in France between 2001 and 2002, the infections were mainly transmitted from one patient to another via the hands of healthcare workers [81]. In this regard, it is agreed that the scrupulous application of universal hygiene precautions is essential to avoid patient-to-patient transmission. A prospective longitudinal study of Belgian patients found that a consistent reduction in the annual incidence of HCV (from 1.41% to 0.56%, and then to 0%) was achieved simply by reinforcing hygienic measures [78] . On the contrary, there is no consensus in the nephrology community concerning the isolation of infected patients and the use of dedicated dialysis machines to prevent HCV infection [78], [82].

Table 3. Prevalence and incidence of HCV infection in patients on chronic hemodialysis in developed countries (1997–2001) [80]
CountryPrevalence (95% CI) (%)Incidence (95% CI) (No. of cases per 100 person/year)
France10.4 (9.7–11.2)2.0 (1.4–2.8)
Germany3.8 (3.3–4.4)1.7 (1.2–2.5)
Italy20.5 (19.4–21.7)3.9 (2.9–5.2)
Japan14.8 (14.0–15.6)3.0 (2.3–3.9)
Spain22.9 (21.7–24.1)3.5 (2.5–4.8)
United Kingdom2.6 (2.1–3.2)1.2 (0.7–2.0)
United States14.0 (13.6–14.5)2.5 (2.1–1.9)

The study included 8615 adult patients attending 308 dialysis facilities. The prevalence and incidence data were adjusted for age, gender, race, time on end-stage renal disease and alcohol or drug abuse [80].

Outside the nephrology setting, cases and outbreaks of HCV transmission have been linked to a number of medical procedures, including the use of contaminated multidose vials [83], [84], [85], [86]; spring-loaded finger sticks [87], [88]; surgical interventions [89], [90], [91]; and gastrointestinal endoscopy [92]. As these cases mainly occur as clusters, no comprehensive and reliable estimates of nosocomial risk are available, but studies of patients with acute and primary HCV infections suggest that a contaminated healthcare environment may be responsible for a substantial number of cases, especially in areas and settings with higher endemic HCV rates. Medical and surgical invasive procedures were the main risk factors associated with anti-HCV seroconversion and acute hepatitis in Italian blood donors [93] and patients enrolled in the registry of the Italian National Hepatitis Surveillance System (SEIEVA) [94]. In addition, outbreaks of infection continue to occur worldwide, mainly due to violations or leaks in safety procedures. In 2000–2002, six cases of anti-HCV seroconversion occurred among 1540 patients hospitalised in a tertiary-care liver unit (accounting for an incidence of 0.27 per 100 hospital admissions per year), and it is worth noting that the main risk factors for seroconversion were the duration of the hospital stay and the presence of an HCV-positive roommate during hospitalisation [95]. In 2005, Macedo de Oliveira and colleagues described an outbreak of 99 cases among the 367 patients treated in a hematology/oncology department that was caused by inadequate infection-control practices [86]. On the other hand, the recent survey by Ciancio et al. [96] found a zero HCV transmission rate among 912 patients undergoing endoscopy with an instrument that had been used for patients with HCV infection but disinfected by means of standard procedures, thus suggesting that the application of the universal precautions is associated with minimal infection rates. The other main issues that should be addressed to improve safety in healthcare environments are over-heavy staff workloads, administrative pressures to reduce costs, and deficiencies in the supervision of personnel [82].

Finally, the transmission of HCV from HCV-infected healthcare providers to their patients has been documented in a number of individual cases and clusters [90], [92], [97], [98], [99], [100], and may be particularly associated with certain types of surgical procedures that can expose patients to the blood of healthcare workers. This mode of HCV transmission is currently deemed to be very rare but, as extensively reviewed elsewhere [101], [102], it is an issue that has complex ethical and forensic implications mainly concerning the possible application of professional restrictions for healthcare workers at risk for transmission.

4.2. Developing countries 

In developing countries, including several of the most populous nations in the world, the risk of acquiring HCV infection through medical procedures is not limited to occasional outbreaks. The use of contaminated injection equipments causes a steady number of unrecognised transmissions on a daily basis and is the major risk factor for HCV infection [103].

A number of epidemiological studies have found substantial associations between HCV seropositivity and the use of unsafe healthcare devices [11], [104], [105]. More than 16 billion injections are administered annually in the poor regions of the world, and the WHO calculates that they account for at least 2.3 million HCV new infections per year, 200,000 HCV-related premature deaths, and 3.6 million years of life lost due to the complications of HCV infections [106].

This continuing iatrogenic epidemic of HCV infection in the poor regions of the world has two main causes: the re-use of injection devices and the administration of unnecessary injections.

In relation to the first, the WHO estimates that 6.7 billion injections (39.3% of all injections) are given via re-used equipment [107], mainly because of financial constraints [106]. The highest reported rates of needle re-use are found in the Middle East, south-east Asia and the western Pacific [107]. Although there is a growing awareness of this problem, as recently as 1998 the WHO was still recommending the re-use of syringes up to 200 times in vaccination programmes, relying on sterilisation routines that are usually not followed [2].

With regard to the second, a number of studies have demonstrated that most of the parenteral treatments administered in developing countries are unnecessary [103], [107], [108]. The distribution of injections within populations is highly clustered, with the average number of injection per year ranging from 0.9 to 8.5 in different countries [103]. Particularly high rates of injection have been described in some countries of the former Soviet Union, where hospitalised children received an average of 65 injections per hospital stay [103]. The most frequently injected medications include antibiotics, vitamins and analgesics that could be taken orally. Furthermore, treatments are commonly provided for non-specific symptoms, including headache, fatigue, nausea, myalgia or fever [103], [109]. As recently reviewed by Simonsen and colleagues, the proportion of unnecessary injections is 70% in Tanzania, 85–99% in Russia, and 82% in Indonesia [103]. Injections are frequently purchased outside the formal healthcare system, and administered by unqualified personnel in pharmacies and marketplaces. This over-use of parenteral therapies in developing countries is due to various factors, including the economic advantage for providers and the popular belief that injections are more effective than other forms of administration [108], [110].

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5. Conclusions 

In resource-rich countries, the use of blood transfusions has reached an unprecedented level of safety with regard to HCV transmission. The risk of acquiring transfusion-transmitted hepatitis C is now below 1 case per million blood units in most countries. However, there are still reports of associations with other medical practices, and residual cases and clusters of iatrogenic HCV transmission, mainly due to breaches of infection-control standards.

The situation is completely different in the poor regions of the world, where several million people acquire HCV infection each year as a result of contaminated blood transfusions and the re-use of infected medical devices. Thus, as pointed out in a recent editorial in this journal by Harvey J. Alter, HCV infection is now a disease of two worlds [111].

More than 15 years after the identification of HCV, it is time to plan and organise a global approach to a global health problem. Much of this task lies in the hands of developed countries, which should start to design comprehensive and interdisciplinary safety interventions. In the specific case of blood transfusion, it is now clear that a number of external factors have so far taken precedence over scientific evidence in pressing for the implementation of safety measures that offer only marginal benefits. The substantial increase in the cost of blood units since the introduction of HCV-NAT has swallowed up resources that could have been dedicated to other primary prevention interventions to reduce the spread of HCV. At a time when healthcare services are having to make an increasing number of choices, it is important that blood transfusion specialists critically examine their own practices and priorities, and discuss them with specialists in other medical disciplines. This approach will ensure that future policy decisions are justifiable to stakeholders and an informed public.

In the global perspective, the uncontrolled HCV epidemic in the poor regions of the world is a cause of great concern. The pattern of viral spread in these areas follows that previously observed in the case of the two other main blood-borne viruses of HBV and HIV, and will probably contribute to increasing morbidity and mortality, thus further depressing human social and economic development.

The differences in the trends of HCV transmission in different regions of the world are of course only a reflection of broader and continuing inequalities in terms of access to modern medical care between the northern and southern hemisphere and, in this regard, developed countries should realise that microbes do not recognise borders. As the HIV epidemic has recently taught us, the rapid and marked changes in human ecology, socio-economic conditions and behaviour characterising our time can profoundly alter the probabilities of the emergence, re-emergence and transmission of infectious diseases [112]. In order to combat the global epidemic of HCV and other blood-borne infections effectively, it is essential to eradicate the massive use of unsafe medical procedures in the poor regions of the world. Our contribution to this task should be seen not only as an act of human solidarity, but also as a precious investment for the future of our own countries.

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Acknowledgements 

I thank Dr José Ramiro Cruz (Pan American Health Organization) and Ms Jan Fordham (World Health Organization) for helpful suggestions and discussions, and professor Jean-Pierre Allain (University of Cambridge, UK) for his critical review of the manuscript.

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PII: S0168-8278(06)00376-X

doi:10.1016/j.jhep.2006.07.003

Journal of Hepatology
Volume 45, Issue 4 , Pages 607-616, October 2006

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