Prevalence and 9-year incidence of hepatitis E virus infection among North Italian blood donors: Estimated transfusion risk

Higher Risk of HEV Transmission and Exposure among Blood Donors in Europe and Asia in Comparison to North America: A Meta-Analysis

Background and aims: The increasing number of diagnosed hepatitis E virus (HEV) infections in Europe has led to the implementation of the testing of blood products in various countries. Many nations have not yet implemented such screening. To assess the need for HEV screening in blood products worldwide, we conducted a systematic review and meta-analysis assessing HEV RNA positivity and anti-HEV seroprevalence in blood donors. Methods: Studies reporting anti-HEV IgG/IgM or HEV RNA positivity rates among blood donors worldwide were identified via predefined search terms in PubMed and Scopus. Estimates were calculated by pooling study data with multivariable linear mixed-effects metaregression analysis. Results: A total of 157 (14%) of 1144 studies were included in the final analysis. The estimated HEV PCR positivity rate ranged from 0.01 to 0.14% worldwide, with strikingly higher rates in Asia (0.14%) and Europe (0.10%) in comparison to North America (0.01%). In line with this, anti-HEV IgG seroprevalence in North America (13%) was lower than that in Europe (19%). Conclusions: Our data demonstrate large regional differences regarding the risk of HEV exposure and blood-borne HEV transmission. Considering the cost–benefit ratio, this supports blood product screening in high endemic areas, such as Europe and Asia, in contrast to low endemic regions, such as the U.S.

Transfusion-transmitted hepatitis E: What we know so far?

Hepatitis E virus (HEV) is a major cause of viral hepatitis globally. There is growing concern about transfusion-transmitted HEV (TT-HEV) as an emerging global health problem. HEV can potentially result in chronic infection in immunocompromised patients, leading to a higher risk of liver cirrhosis and even death. Between 0.0013% and 0.281% of asymptomatic blood donors around the world have HEV viremia, and 0.27% to 60.5% have anti-HEV immunoglobulin G. HEV is infectious even at very low blood concentrations of the virus. Immunosuppressed patients who develop persistent hepatitis E infection should have their immunosuppressant regimen reduced; ribavirin may be considered as treatment. Pegylated interferon can be considered in those who are refractory or intolerant to ribavirin. Sofosbuvir, a nucleotide analog, showed modest antiviral activity in some clinical studies but sustained viral response was not achieved. Therefore, rescue treatment remains an unmet need. The need for HEV screening of all blood donations remains controversial. Universal screening has been adopted in some countries after consideration of risk and resource availability. Various pathogen reduction methods have also been proposed to reduce the risk of TT-HEV. Future studies are needed to define the incidence of transmission through transfusion, their clinical features, outcomes and prognosis.

Seroprevalence of hepatitis E virus in Argentinean blood donors

BACKGROUND

Hepatitis E virus (HEV) is the main cause of enteric acute viral hepatitis worldwide. In this epidemiological framework, it has become a threat to blood safety and a relevant issue for blood transfusions. However, there is a paucity of data regarding prevalence of HEV infection. The aim of this study was to determine HEV seroprevalence in blood donors from different regions from Argentina.

MATERIAL AND METHODS

Serum samples from 391 individuals attending five blood donor centers located in different regions from Argentina were analyzed for anti-HEV IgG and anti-HEV IgM.

RESULTS

Overall, anti-HEV IgG was detected in 44 out of 391 (11.3%) samples. HEV prevalence ranged from 5.1 to 20.0% among different country regions. A significant difference in blood donors' age was observed between anti-HEV IgG positive and negative individuals [44 (37-51) vs. 35 (27-43), P < 0.001, respectively]. Anti-HEV IgM was detected in 8 out of 44 (18.2%) anti-HEV IgG positive cases.

CONCLUSION

Anti-HEV IgG was detected in blood donor samples from five analyzed Argentinean regions, highlighting the wide distribution of the virus in the country. HEV prevalence was variable among different regions and significantly higher in older donors. Given the evidence of anti-HEV IgM presence in blood donors, suggesting a potential risk of transfusion-transmitted HEV, screening for HEV in blood units to be used in vulnerable population would be desirable. Molecular studies for detection of viremic donors and donor-recipients follow-up are necessary to certainly determine the risk of transfusion-transmitted HEV in Argentina.

SARS-CoV-2 seroprevalence trends in healthy blood donors during the COVID-19 outbreak in Milan

BACKGROUND

The Milan metropolitan area in Northern Italy was among the most severely hit by the SARS-CoV-2 outbreak. The aim of this study was to examine the seroprevalence trends of SARS-CoV-2 in healthy asymptomatic adults, and the risk factors and laboratory correlates of positive tests.

MATERIALS AND METHODS

We conducted a cross-sectional study in a random sample of blood donors, who were asymptomatic at the time of evaluation, at the beginning of the first phase (February 24th to April 8th 2020; n=789). Presence of IgM/IgG antibodies against the SARS-CoV-2-Nucleocapsid protein was assessed by a lateral flow immunoassay.

RESULTS

The test had a 100/98.3 sensitivity/specificity (n=32/120 positive/negative controls, respectively), and the IgG test was validated in a subset by an independent ELISA against the Spike protein (n=34, p<0.001). At the start of the outbreak, the overall adjusted seroprevalence of SARS-CoV-2 was 2.7% (95% CI: 0.3-6%; p<0.0001 vs 120 historical controls). During the study period, characterised by a gradual implementation of social distancing measures, there was a progressive increase in the adjusted seroprevalence to 5.2% (95% CI: 2.4-9.0; 4.5%, 95% CI: 0.9-9.2% according to a Bayesian estimate) due to a rise in IgG reactivity to 5% (95% CI: 2.8-8.2; p=0.004 for trend), but there was no increase in IgM+ (p=not significant). At multivariate logistic regression analysis, IgG reactivity was more frequent in younger individuals (p=0.043), while IgM reactivity was more frequent in individuals aged >45 years (p=0.002).

DISCUSSION

SARS-CoV-2 infection was already circulating in Milan at the start of the outbreak. The pattern of IgM/IgG reactivity was influenced by age: IgM was more frequently detected in participants aged >45 years. By the end of April, 2.4-9.0% of healthy adults had evidence of seroconversion.

SARS-CoV-2 seroprevalence trends in healthy blood donors during the COVID-19 outbreak in Milan

BACKGROUND

The Milan metropolitan area in Northern Italy was among the most severely hit by the SARS-CoV-2 outbreak. The aim of this study was to examine the seroprevalence trends of SARS-CoV-2 in healthy asymptomatic adults, and the risk factors and laboratory correlates of positive tests.

MATERIALS AND METHODS

We conducted a cross-sectional study in a random sample of blood donors, who were asymptomatic at the time of evaluation, at the beginning of the first phase (February 24^th to April 8^th 2020; n=789). Presence of IgM/IgG antibodies against the SARS-CoV-2-Nucleocapsid protein was assessed by a lateral flow immunoassay.

RESULTS

The test had a 100/98.3 sensitivity/specificity (n=32/120 positive/negative controls, respectively), and the IgG test was validated in a subset by an independent ELISA against the Spike protein (n=34, p<0.001). At the start of the outbreak, the overall adjusted seroprevalence of SARS-CoV-2 was 2.7% (95% CI: 0.3-6%; p<0.0001 vs 120 historical controls). During the study period, characterised by a gradual implementation of social distancing measures, there was a progressive increase in the adjusted seroprevalence to 5.2% (95% CI: 2.4-9.0; 4.5%, 95% CI: 0.9-9.2% according to a Bayesian estimate) due to a rise in IgG reactivity to 5% (95% CI: 2.8-8.2; p=0.004 for trend), but there was no increase in IgM⁺ (p=not significant). At multivariate logistic regression analysis, IgG reactivity was more frequent in younger individuals (p=0.043), while IgM reactivity was more frequent in individuals aged >45 years (p=0.002).

DISCUSSION

SARS-CoV-2 infection was already circulating in Milan at the start of the outbreak. The pattern of IgM/IgG reactivity was influenced by age: IgM was more frequently detected in participants aged >45 years. By the end of April, 2.4-9.0% of healthy adults had evidence of seroconversion.

Diagnosis and Management of Autoimmune Hemolytic Anemia in Patients with Liver and Bowel Disorders

Anemia is a common feature of liver and bowel diseases. Although the main causes of anemia in these conditions are represented by gastrointestinal bleeding and iron deficiency, autoimmune hemolytic anemia should be considered in the differential diagnosis. Due to the epidemiological association, autoimmune hemolytic anemia should particularly be suspected in patients affected by inflammatory and autoimmune diseases, such as autoimmune or acute viral hepatitis, primary biliary cholangitis, and inflammatory bowel disease. In the presence of biochemical indices of hemolysis, the direct antiglobulin test can detect the presence of warm or cold reacting antibodies, allowing for a prompt treatment. Drug-induced, immune-mediated hemolytic anemia should be ruled out. On the other hand, the choice of treatment should consider possible adverse events related to the underlying conditions. Given the adverse impact of anemia on clinical outcomes, maintaining a high clinical suspicion to reach a prompt diagnosis is the key to establishing an adequate treatment.