High prevalence of hepatitis A and B nonimmunity in pediatric liver transplant recipients.

BACKGROUND: Pediatric liver transplant recipients are at increased risk of post-transplant infections. The purpose of this study was to quantify hepatitis A and B non-immunity based on antibody titers in liver transplant recipients. METHODS: We conducted a retrospective chart review of 107 pediatric liver transplant recipients at a single medical center from 2000 to 2017. We compared hepatitis immune patients to non-immune patients and studied response to vaccination in patients immunized post-transplantation. RESULTS: Eighty-one percent of patients had pre-transplant immunity to hepatitis A whereas 68% had pre-transplant immunity to hepatitis B. Post-transplant hepatitis B immunity decreased to 33% whereas post-transplant hepatitis A immunity remained high at 82%. Older age and time since transplantation were significantly associated with hepatitis B non-immunity. Most patients responded to doses post-transplantation with 78% seroconversion following hepatitis A re-immunization and 83% seroconversion following hepatitis B re-immunization. CONCLUSIONS: Pediatric liver transplant recipients are at risk of hepatitis A and B non-immunity, particularly with respect to hepatitis B. Boosters post-transplant may improve immunity to hepatitis viruses.

Sexual practices and the risk of Hepatitis A in men who have sex with men in Spain.

AIM: To determine the frequency of and identify risk factors associated with sexual practices leading to hepatitis A infection in the population of men who have sex with men in Spain. BACKGROUND: The increased incidence of hepatitis A as a result of sexual contact among this population is a public health concern and a challenge in controlling sexually transmitted infections. METHODS: This cross-sectional, online survey-based study included 881 men who have sex with men. Unprotected oro-anal and insertive-anal sex are considered to be unsafe sexual practices associated with hepatitis A infection. RESULTS: Of all respondents, 83.4% engaged in insertive-anal sex and 71.3% in unprotected oro-anal sex during the previous 12 months. An association was found with sociodemographic factors [living alone (OR = 2; 95%CI = 1.13-3.35)] and contextual factors of sexual behaviour [previous diagnosis of sexually transmitted infection(s) (OR = 1.74; 95%CI = 1.15-2.61) and participating in 'chemsex' (OR = 5.15; 95%CI = 1.05-25.15)]. CONCLUSION: The frequency of unsafe sexual practices associated with hepatitis A among men who have sex with men in Spain is high. Interventions based on sociodemographic and contextual factors of sexual behaviour should be implemented. IMPLICATIONS FOR NURSING MANAGEMENT: Nurse managers should update and incorporate the support needs of men who have sex with men and take advantage of the opportunity to implement harm reduction strategies.

Hepatitis A Virus Genotype IB Outbreak among Internally Displaced Persons, Syria.

In 2018, a hepatitis A virus outbreak was identified among internally displaced persons in Syria. Sequence analysis based on the viral protein 1/2A junction revealed that the causative virus belonged to genotype IB. A high displacement rate, deteriorated sanitary and health conditions, and poor water quality likely contributed to this outbreak.

Acute hepatitis A is the chief etiology of acute hepatitis in Egyptian children: a single-center study.

Acute hepatic illness is an important health issue in children. Our work aimed to determine the prevalence of viral hepatitis in symptomatic children. It is a prospective cohort study of 268 children presented with acute hepatitis. Complete blood count, liver panel, and anti-hepatitis A virus (HAV) IgM were done initially. Cases negative for HAV were tested for anti-hepatitis E (HEV) IgM, anti-Epstein-Barr virus viral capsid antigen (EBV VCA) IgM, anti-cytomegalovirus virus IgM, hepatitis B surface antigen, anti-hepatitis B core IgM antibody, and anti-HCV antibody. Anti-HCV was repeated after 12 weeks to exclude seroconversion. In cases with negative viral serology, ceruloplasmin, total immunoglobulin G, antinuclear antibody, and abdominal ultrasound were done. Follow-up visits were bimonthly till recovery, then after 6 months. The mean age ± SD was 7.1 ± 3.7 years (1.5-18), and 56% were males. Acute HAV infection was diagnosed in 260 (97%) of cases and acute EBV infection in one case (0.4%). HAV/HEV coinfection was excluded in 70 HAV-positive cases. Six (2.2%) children remain undiagnosed and one child lost follow-up. About 80% of HAV-cases had normal laboratory results within 45 days. Unusual presentation of HAV infection was noticed in six children: four (1.5%) were relapsing, one had a cholestatic course, and one case had severe hemolytic anemia. Acute HAV infection was the chief etiology of acute hepatitis in our Egyptian children. The majority of the presentations were mild and children recover within a few weeks. An unusual pattern of HAV in children can be observed in endemic areas.

Comparing the Clinical Features and Outcomes of Acute Hepatitis E Viral Infections with Those of Acute Hepatitis A, B, and C Infections in Korea.

OBJECTIVES: This study investigated the etiology of acute viral hepatitis and compared the clinical features of hepatitis E virus (HEV) infections with those of other acute viral hepatitis infections in Korea. METHODS: This study included 2,357 consecutive patients who were diagnosed with acute hepatitis, based on acute illness with jaundice or elevated alanine aminotransferase levels (>100 IU/L), between January 2007 and January 2016. Acute viral infections were observed in 23 (19.8%) patients with HEV, 49 (42.2%) patients with hepatitis A virus, 28 (24.1%) patients with hepatitis B virus, and 16 (13.8%) patients with hepatitis C virus. RESULTS: The incidence of acute HEV infection was higher among older patients (median age: 49 years) and male patients (69.6%), and was associated with the consumption of undercooked or uncooked meat (43.5%). Half of the acute HEV infections involved underlying liver disease, such as alcoholic liver disease, chronic hepatitis B, common bile duct stones, and autoimmune hepatitis. Two HEV-infected patients were diagnosed with Guillain-Barré syndrome, although no patients developed fulminant hepatitis. CONCLUSION: Our findings indicate that HEV infection in Korea is frequently transmitted through the consumption of raw meat and may cause acute or chronic liver disease.

Genotypes of hepatitis a virus in Turkey: first report and clinical profile of children infected with sub-genotypes IA and IIIA.

BACKGROUND: Hepatitis A virus (HAV) is a food and water-borne virus causing clinical (mainly hepatitis) and subclinical disease in humans. It is important to characterize circulating strains of HAV in order to prevent HAV infections using efficacious vaccines. The aim of this study was the detection and characterization of the circulating strains of HAV in Turkey by performing serology, RT-PCR, sequencing and phylogenetic analysis. METHODS: In this study, 355 HAV suspected cases were analysed by ELISA for the presence of antibodies to HAV. RNA was extracted from 54 HAV IgM positive human sera. None of the suspect cases were vaccinated against HAV and they never received blood transfusions. Samples found positive by RT-PCR using primers targeting the VP1/VP2A junction and VP1/VP3 capsid region of HAV, were subjected to sequencing and phylogenetic analyses. RESULTS: IgM type antibodies to HAV were detected in 54 patients. Twenty one of them were students. The age of IgM positive cases was between 3 and 60 years. IgM positivity differed in age groups and was higher in the age group 3 to 10 years. Phylogenetic analysis showed that the majority of HAV strains detected in this study belong to the "HAV 1B" cluster. In addition, the HAV sub-genotypes IA (KT874461.1) and IIIA (KT222963.1) were found in 2 children. These sub-genotypes were not previously reported in Turkey. The child who carried sub-genotype IIIA travelled to Afghanistan and presented with abdominal pain, icterus and vomitus. He was positive for anti-HAV IgM and IgG but negative for hepatitis B and C. Liver enzymes like aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transferase and lactate dehydrogenase were severely elevated. Bilirubin levels were also increased. White blood cells, neutrophils and hemoglobin were decreased while lymphocytes and monocytes were increased. Similar clinical signs and laboratory findings were reported for the child infected with sub-genotype IA but aspartate aminotransferase and alanine aminotransferase were not severely elevated. CONCLUSIONS: The results indicate that molecular studies determining the HAV genotype variation in Turkey are timely and warranted. The majority of IgM positive cases in 3-10 year old patients indicate that childhood vaccination is important. Sub-genotype IB is the most prevalant genotype in Turkey. Surprisingly, sub-genotype IA and IIIA are also present in Turkey; future diagnostic efforts need to include diagnostic methods which can identify this emerging HAV genotypes. Our results also show that one important risk factor for contracting hepatitis A virus is international travel since genotype IIIA was detected in a child who had travelled to Afghanistan.

Clinical characteristics of acute hepatitis A outbreak in Taiwan, 2015-2016: observations from a tertiary medical center.

BACKGROUND: Acute hepatitis A is a fecal-oral transmitted disease related to inadequate sanitary conditions. In addition to its traditional classification, several outbreaks in the men who have sex with men (MSM) population have resulted in acute hepatitis A being recognized as a sexually transmitted disease. However, few studies have clarified the clinical manifestations in these outbreaks involving the MSM population. METHODS: Beginning in June 2015, there was an outbreak of acute hepatitis A involving the MSM population in Northern Taiwan. We conducted a 15-year retrospective study by recruiting 207 patients with the diagnosis of acute hepatitis A that included the pre-outbreak (January 2001 to May 2015) and outbreak (June 2015 to August 2016) periods in a tertiary medical center in Northern Taiwan. Using risk factors, comorbidities, presenting symptoms, laboratory test results and imaging data, we aimed to evaluate the clinical significance of acute hepatitis A in the MSM population, where human immunodeficiency virus (HIV) coinfection is common. RESULTS: There was a higher prevalence of reported MSM (p < 0.001), HIV (p < 0.001) and recent syphilis (p < 0.05) coinfection with acute hepatitis A during the outbreak period. The outbreak population had more prominent systemic symptoms, was more icteric with a higher total bilirubin level (p < 0.05) and had a 7-times higher tendency (p < 0.05) to have a hepatitis A relapse. CONCLUSIONS: The clinical course of acute hepatitis A during an outbreak involving the MSM and HIV-positive population is more symptomatic and protracted than in the general population.

An Outbreak of Acute Hepatitis Caused by Genotype IB Hepatitis A Viruses Contaminating the Water Supply in Thailand.

BACKGROUND: In 2000, an outbreak of acute hepatitis A was reported in a province adjacent to Bangkok, Thailand. AIMS: To investigate the cause of the 2000 hepatitis A outbreaks in Thailand using molecular epidemiological analysis. METHODS: Serum and stool specimens were collected from patients who were clinically diagnosed with acute viral hepatitis. Water samples from drinking water and deep-drilled wells were also collected. These specimens were subjected to polymerase chain reaction (PCR) amplification and sequencing of the VP1/2A region of the hepatitis A virus (HAV) genome. The entire genome sequence of one of the fecal specimens was determined and phylogenetically analyzed with those of known HAV sequences. RESULTS AND CONCLUSIONS: Eleven of 24 fecal specimens collected from acute viral hepatitis patients were positive as determined by semi- nested reverse transcription PCR targeting the VP1/2A region of HAV. The nucleotide sequence of these samples had an identical genotype IB sequence, suggesting that the same causative agent was present. The complete nucleotide sequence derived from one of the samples indicated that the Thai genotype IB strain should be classified in a unique phylogenetic cluster. The analysis using an adjusted odds ratio showed that the consumption of groundwater was the most likely risk factor associated with the disease.

Case report of a transfusion-associated hepatitis A infection.

BACKGROUND: Documented transfusion-associated hepatitis A (TAHA) is rare, and blood donors in the United States are not routinely screened for this infection. We report a case of TAHA associated with a donation made 8 days after a donor returned from a trip to South America. STUDY DESIGN AND METHODS: This is a review of donor and recipient records and a review of the literature. RESULTS: A donor developed symptoms of hepatitis 20 days after donation (28 days after returning from South America). The donor reported the illness 56 days after donation when contacted to schedule another visit. By this time, the red blood cell and frozen plasma components had been transfused. The recipient of the plasma, a 15-month-old female, tested positive for immunoglobulin M antibody to hepatitis A virus 43 days after transfusion. The recipient had displayed mild, nonspecific symptoms approximately 2 weeks after transfusion. Hospital infection control investigated the potential for further spread within the hospital because the recipient had been an inpatient for most of the posttransfusion period. The risk of transmission to other patients was determined to be negligible because the patient had been in isolation for other reasons. Family members, who included a health care professional, were counseled and offered prophylaxis. CONCLUSION: TAHA may be underrecognized. This case was identified only because of a donor report at the time of recruitment. Asymptomatic donor viremia has been documented in plasma donors. Although TAHA rarely results in severe disease, the risk it creates of secondary transmission especially within the hospital setting is not inconsequential.

SMOKE IT! Promoting a change of opiate consumption pattern - from injecting to inhaling.

BACKGROUND: Intravenous drug use has been predominantly practised since illegal heroin use became known in Germany in the early 1970s. The available data suggest that the risk of accidental overdose when smoking heroin is substantially reduced compared to injecting a substance of unknown purity and quality. Moreover, the risk of transmitting HIV, Hepatitis B or C via blood contact is considerably reduced when smoking heroin rather than when injecting it intravenously. In spite of the significant strain on the lungs and the respiratory tract caused by smoking, it can be concluded that inhalative use - measured by the indicators 'overdose' and 'viral infections' is considerably less dangerous than intravenous use. Despite these harm-reducing effects of inhalative use, there is only very limited scientific survey on this subject. The project 'SMOKE IT!' studied to what extent a change of the consumption method can be supported by making new equipment for drug use available. METHOD: 'SMOKE IT!' was carried out as a multi-centre survey in drug consumption rooms (DCRs) in five German cities. Participants received 'SMOKE-IT!' packs that contained new heroin smoking foils, as well as information about inhalative drug use. The quantitative data collection was aided by a written questionnaire filled out at three different stages in 2012. RESULTS: The vast majority of the 165 respondents favoured using the foils from the 'SMOKE-IT!' packs (82.5%). The survey shows that two-thirds of the sample used the SMOKE-IT foils for inhaling instead of injecting. Almost six out of ten said that smoking was healthier than injecting. Thirty-five percent of the participants named the reduced risk of a hepatitis or HIV infection as a particularly important factor. A third of the respondents used the smoking foils to avoid the danger of an overdose. CONCLUSIONS: Targeted media and personal intervention in association with the dispensation of attractive drug use equipment can motivate opiate users to change their method of drug use. The main reason for inhalative use is that it is significantly less dangerous, measured by the indicators 'overdose' and 'viral infections'. All drop-in centres should expand their syringe-exchange services to include the dispensation of smoking foils.

Isolated granulomatous hepatitis-A histopathological surprise mimicking cholangiocarcinoma in ulcerative colitis.

A 63-yr-old woman, known case of ulcerative colitis, was diagnosed with sclerosing cholangitis 2 years back. She was admitted for investigation of abdominal discomfort, fatigue with elevated alkaline phosphatase and deranged liver function test. Imaging studies (computerised tomography and magnetic resonance imaging) demonstrated a normal biliary tree with focal hepatic lesion which was showing features of cholangiocarcinoma. Ultrasound guided biopsy of the lesion surprisingly revealed non caseating granulomata. Granulomatous hepatitis occurs in less than 1 percent of cases of inflammatory bowel disease. A clinical diagnosis of isolated granulomatous hepatitis was established as the lesion remained stable on follow up and no other cause for it was identified on further investigation. Although the differential diagnosis of focal hepatic lesion in patients with ulcerative colitis with sclerosing cholangitis is wide, granulomatous hepatitis presenting as focal mass lesion mimicking cholangiocarcinoma has never been described previously.

Risk factors for acute hepatitis A infection in Korea in 2007 and 2009: a case-control study.

This study aimed to identify the risk factors associated with acute hepatitis A virus (HAV) infection in the Korean population. Participants were recruited from five referral hospitals across the country in 2007 and from 11 hospitals in 2009. Patients with positive anti-HAV IgM antibody tests became the case group, while patients treated for non-contagious diseases at the same hospitals were recruited as controls. A total of 222 and 548 case-control pairs were studied in the 2007 and 2009 surveys, respectively. Data from the surveys were analyzed jointly. In a multivariate analysis, sharing the household with HAV-infected family members (OR, 6.32; 95% CI, 1.4-29.6), contact with other HAV-infected individuals (OR, 4.73; 95% CI, 2.4-9.4), overseas travel in 2007 (OR, 19.93; 95% CI, 2.3-174.4), consumption of raw shellfish (OR, 2.51; 95% CI, 1.8-3.5), drinking bottled water (OR, 1.64; 95% CI, 1.3-8.4), and occupation that involve handling food (OR, 3.30; 95% CI, 1.3-8.4) increased the risk of HAV infection. Avoiding contact with HAV-infected individuals and avoiding raw foods eating could help minimize the risk of hepatitis A infection. Immunization must be beneficial to individuals who handle food ingredients occupationally or travel overseas to HAV-endemic areas.

A hepatitis A, B, C and HIV prevalence and risk factor study in ever injecting and non-injecting drug users in Luxembourg associated with HAV and HBV immunisations.

BACKGROUND: In Luxembourg, viral hepatitis and HIV infection data in problem drug users (PDUs) are primarily based on self-reporting. Our study aimed to determine the prevalence of HAV, HBV, HCV and HIV infections in ever injecting (IDUs) and non-injecting drug users (nIDUs) including inherent risk factors analysis for IDUs. Secondary objectives were immunisation against HAV and HBV, referral to care and treatment facilities as well as reduction in risk behaviour. METHODS: A nationwide, cross-sectional multi-site survey, involving 5 in-, 8 out-treatment and 2 prison centres, included both an assisted questionnaire (n = 368) and serological detection of HIV and Hepatitis A, B, C (n = 334). A response rate of 31% resulted in the participation of 310 IDUs and 58 nIDUs. Risk factors such as drug use, sexual behaviour, imprisonment, protection and health knowledge (HAV, HBV status and immunisations, HCV, HIV), piercing/tattoo and use of social and medical services were studied by means of chi2 and logistic models. RESULTS: Seroprevalence results for IDUs were 81.3% (218/268, 95%CI=[76.6; 86.0]) for HCV, 29.1% (74/254, 95%CI=[25.5;34.7 ]) for HBV (acute/chronic infection or past cured infection), 2.5% (5/202, 95%CI=[0.3; 4.6]) for HIV-1 and 57.1% (108/189, 95%CI=[50.0; 64.1]) for HAV (cured infections or past vaccinations). Seroprevalence results for nIDUs were 19.1% (9/47, 95%CI=[7.9;30.3]) for HCV, 8.9% (4/45, 95%CI=[0.6;17.2]) for HBV (acute/chronic infection or past cured infection), 4.8% (2/42, 95%CI=[-1.7;11.3]) for HIV-1 and 65.9% (27/41, 95%CI=[51.4;80.4]) for HAV. Prisoners showed the highest rates for all infections. Age, imprisonment and setting of recruitment were statistically associated with HCV seropositivity. Age, speedball career and nationality were significantly associated with HBV seropositivity. Only 56% of the participants in outpatient centres collected their serology results and 43 doses of vaccine against HAV and/or HBV were administered. CONCLUSIONS: Despite the existing national risk-reduction strategies implemented since 1993, high prevalence of HCV and HBV infections in injecting drug users is observed. Our study showed that implementing risk-prevention strategies, including immunisation remains difficult with PDUs. Improvement should be looked for by the provision of field healthcare structures providing tests with immediate results, advice, immunisation or treatment if appropriate.

Fitz-Hugh-Curtis syndrome: abdominal pain in women of 26 years old.

Fitz-Hugh-Curtis syndrome is an inflammation of the liver capsule as a complication of pelvic inflammatory disease, whose etiologic agent is the most common C. trachomatis. The acute phase Fitz-Hugh-Curtis syndrome may present with pain in upper right quadrant abdomen, commonly confused with other diseases of the hepatobiliary and gastrointestinal tract. Definitive diagnosis is now possible for non-invasive techniques such as ultrasound, computed tomography, as well as techniques for the isolation of the germ responsible available in most centers.

Relative share of asymptomatic forms of hepatitis a in Plovdiv region, Bulgaria.

OBJECTIVE: To study the relative share of asymptomatic forms of Hepatitis A in family reservoirs of infection with different hygienic conditions. MATERIALS AND METHODS: Asymptomatic forms were identified by detecting anti-HAV IgM using ELISA. Two types of households: with poor hygiene and with good hygiene, were studied. The study was designed as case-control. A group of Hepatitis A contact children attending day nurseries and kindergartens was also included in the study. RESULTS: The relative share of asymptomatic forms of HAV infection in poor hygiene households was 58.62%, while in those with good hygiene it was 41.57%. The comparison using Fisher's exact test yielded OR = 1.99 and 95% CI (P < 0.05). Asymptomatic forms were found in 7.75% of the investigated contacts among children attending day nurseries and kindergartens. CONCLUSION: Asymptomatic forms of hepatitis A are very common which makes them epidemiologically quite significant as many of the cases remain unrecognized and later become focal points of new cases of the disease. Poor hygiene conditions are likely to cause more asymptomatic forms. The high relative share of asymptomatic forms found in the households supports the need for immunoprophylaxis of the contacts.

Probable Nipa Palm Wine-Associated Hepatitis A Outbreak after Attending a Funeral Ceremony in Sabah.

Foodborne outbreaks of hepatitis A virus (HAV) are most commonly associated with fresh and frozen produce and with various types of shellfish. Alcoholic beverage-borne outbreaks of hepatitis A are extremely rare. Here, we report an outbreak of hepatitis A associated with the consumption of a traditional wine at a funeral ceremony in the Sabah state of Malaysian Borneo. Confirmed cases were determined by serum anti-HAV immunoglobulin M and/or for fecal HAV by reverse transcription polymerase chain reaction (RT-PCR). The amplicons of RT-PCR were subjected to nucleotide sequencing followed by phylogenetic analysis. We conducted a 1:2 case-control study to identify the possible exposure that led to the outbreak. Sixteen patients met the case definition, they were 18 to 58 years old and 90% of them were males. The case-control study showed that the consumption of nipa palm wine during the ceremony was significantly associated (P = 0.0017) with hepatitis A infection (odds ratio, 5.44; 95% CI, 1.80-16.43). Untreated river water was used to dilute the traditional wine, which was assumed to be the source of the infection. Phylogenetically, these viruses belonged to genotype IA and formed an independent cluster with strains from Taiwan, Japan, and the Philippines. This strain might be an emerging HAV in Asian countries. Environmental assessments were performed and environmental samples were negative for HAV. The incidence of hepatitis A in Sabah was also determined and it was 0.795/100,000 population. Strict monitoring of traditional wine production should be implemented by the local authority to prevent future outbreaks.

An outbreak of hepatitis A in Roma populations living in three prefectures in Greece.

An outbreak of hepatitis A virus (HAV) infection affected Roma populations living in three prefectures of northeastern Greece. Between July and November 2007, 124 cases were reported. We carried out investigations to characterize the pathogen, to identify the source of infection and the route of transmission. Using the RT-PCR technique, HAV strains of the same genotype were detected in all sera from a subset of patients with acute disease. These showed more than 99.8% identity, suggesting a common source. A questionnaire was also completed to collect clinical and epidemiological information. The outbreak affected mainly Roma children aged <10 years. An inspection of Roma settlements showed that poor sanitary conditions were associated with the HAV outbreak.

Update: a food-borne outbreak of hepatitis A in the Netherlands related to semi-dried tomatoes in oil, January-February 2010.

Between 31 December 2009 and 10 February 2010, 13 patients were infected by an identical hepatitis A virus strain not previously detected in the Netherlands. They had not been abroad and were widely distributed over the Netherlands. A case-control study including 12 cases and 44 controls identified semi-dried tomatoes in oil as the source of the outbreak (odds ratio: 20.0; 95% confidence interval: 1.5-274). The virus was not detected in any of 81 tested food samples. International trace-back is still ongoing.

A possible foodborne outbreak of hepatitis A in the Netherlands, January-February 2010.

As of 1 March 2010, a total of 11 primary cases with onset of symptoms between 31 December 2009 and 10 February 2010, have been identified with identical hepatitis A genotype IB strains in the Netherlands. A relation with Australian and French foodborne outbreaks occurring in 2009 and 2010 is suspected. Ten of the 11 primary cases indicated that they had consumed one or more products containing semi-dried tomatoes during their incubation period.

Assessing the risk of a community outbreak of hepatitis A on blood safety in Latvia, 2008.

Post-transfusion hepatitis A virus (HAV) infection worldwide is considered a sporadic event. An outbreak of HAV infection occurred in Latvia between the end of 2007 and throughout 2008 with more than 2,800 confirmed cases reported over a 13-month period (incidence of 123 per 100,000 population). The majority of reported HAV infection cases were in people over 18 years of age and in people living in the capitalcity, Riga. We estimated that the crude risk for HAV contamination of whole blood supplies in Riga between February and October 2008 ranged from 1.4 to 10.6 per 10,000 donated units. In people under 40 years of age, the risk of receiving an infectious blood transfusion was more than 3.0 per 10,000 recipients between August and October 2008 during the peak of the outbreak. We conclude that there is a previously under-recognised impact of HAV on blood safety during widespread outbreaks of this disease. Estimating the risk of contamination of blood supplies during an infectious disease outbreak scenario is important for fine tuning risk assessments and potentially improving public health practices.