Booster vaccinations and Omicron: the effects on SARS-CoV-2 antibodies in Dutch blood donors.

INTRODUCTION: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) booster vaccination campaign and the emergence of SARS-CoV-2 Omicron variants impact the prevalence and levels of SARS-CoV-2 antibodies in the Netherlands. In this study we determined antibody levels across age groups, the impact of Omicron variant infections, and the effect of booster vaccinations on antibody levels. METHODS: In September and December 2021 and in February 2022, over 2000 Dutch blood donors were tested for presence of SARS-CoV-2 antibodies. Donations were selected based on age, sex, and region of residence, to provide an optimal coverage and representation of the Dutch population. RESULTS: Levels of vaccination-induced spike antibodies decreased over time in all age groups. Donors vaccinated with Janssen or AstraZeneca had significantly lower antibody levels than donors vaccinated with Pfizer or Moderna vaccine. Boostering with an mRNA vaccine elevated antibody levels in all age-groups irrespective of the initial vaccine. In donors aged < 56 years, the proportion of infected donors almost doubled between December 2021 and February 2022. CONCLUSION: The booster vaccination campaign increased antibody levels in all age-groups. After a booster vaccination, donors initially vaccinated with AstraZeneca or Janssen vaccine showed antibody levels similar to donors initially vaccinated with an mRNA vaccine. The emergence of the SARS-CoV-2 Omicron variant in the Netherlands caused a substantial increase in donors with infection-induced antibodies, especially among younger donors.

Inflammatory responses in SARS-CoV-2 associated Multisystem Inflammatory Syndrome and Kawasaki Disease in children: An observational study.

Multisystem Inflammatory Syndrome in Children (MIS-C) is a severe inflammatory disease in children related to SARS-CoV-2 with multisystem involvement including marked cardiac dysfunction and clinical symptoms that can resemble Kawasaki Disease (KD). We hypothesized that MIS-C and KD might have commonalities as well as unique inflammatory responses and studied these responses in both diseases. In total, fourteen children with MIS-C (n=8) and KD (n=6) were included in the period of March-June 2020. Clinical and routine blood parameters, cardiac follow-up, SARS-CoV-2-specific antibodies and CD4+ T-cell responses, and cytokine-profiles were determined in both groups. In contrast to KD patients, all MIS-C patients had positive Spike protein-specific CD3+CD4+ T-cell responses. MIS-C and KD patients displayed marked hyper-inflammation with high expression of serum cytokines, including the drug-targetable interleukin (IL)-6 and IFN-γ associated chemokines CXCL9, 10 and 11, which decreased at follow-up. No statistical differences were observed between groups. Clinical outcomes were all favourable without cardiac sequelae at 6 months follow-up. In conclusion, MIS-C and KD-patients both displayed cytokine-associated hyper-inflammation with several high levels of drug-targetable cytokines.

Diagnostic performance of the ZEUS Borrelia VlsE1/pepC10 assay in European LB patients: a case-control study.

This retrospective case-control study assesses the sensitivity, specificity, and area under the curve of the ZEUS Borrelia VlsE1/pepC10 assay in comparison with the C6-ELISA in European patients with Lyme borreliosis, healthy blood donors, and potentially cross-reactive controls. We included a convenience series of 161 sera from patients with physician-confirmed early localized or disseminated Lyme borreliosis (n = 143), 400 sera from healthy blood donors and 44 sera with potentially cross-reactive antibodies, on which we performed the aforementioned serological assays and the recomLine immunoblot. Diagnostic parameters were compared in various single-tier and two-tier algorithms. The specificities of the C6-ELISA and the ZEUS Borrelia VlsE1/pepC10 were comparable in healthy blood donors (e.g., single-tier permissive: C6: 362/400, 90.5% [87.2-93.2]; VlsE1/pepC10: 361/400, 90.3% [86.9-93.0]). The C6-ELISA had an apparently higher sensitivity in EM sera (e.g., both time points combined: C6: 61/76, 80.3% [69.5-88.5]; VlsE1/pepC10: 54/76, 71.1% [59.5-80.9]), but these differences were all not-significant. Interestingly, the VlsE1/pepC10 assay had a significantly higher specificity in sera with potentially cross-reactive antibodies (e.g., single-tier permissive: C6: 34/44, 77.3% [62.2-88.5]; VlsE1/pepC10: 40/44, 90.9% [78.3-97.5]; p = 0.031). While the areas under the curve for both assays were excellent, that of the C6-ELISA exceeded that of the VlsE1/pepC10 (C6: AUC = 0.925; VlsE1/pepC10: AUC = 0.878; p = 0.003). The novel ZEUS Borrelia VlsE1/pepC10 assay has generally comparable diagnostic parameters to the C6-ELISA with potentially improved specificity in cross-reactive sera. Thus, it is a useful tool for the serodiagnosis of Lyme borreliosis in Europe.

HBsAg loss after peginterferon-nucleotide combination treatment in chronic hepatitis B patients: 5 years of follow-up.

Combining peginterferon-alfa-2a (pegIFN) with a nucleotide analogue can result in higher rates of HBsAg loss than either therapy given alone. Here, we investigated the durability of the response to combination therapy in chronic hepatitis B (CHB) patients after 5 years of follow-up. In the initial study, 92 CHB patients (44 HBeAg-positive, 48 HBeAg-negative) with HBV DNA >100 000 c/mL (~20 000 IU/mL) and active hepatitis were treated for 48 weeks with pegIFN 180 µg/week and 10 mg adefovir dipivoxil daily. For the long-term follow-up (LTFU) study, patients were followed up for 5 years after the end of treatment. At year 5, 70 (32 HBeAg-positive, 38 HBeAg-negative) patients remained in the study. At year 5, 19% (6/32) of HBeAg-positive patients and 16% (6/38) of HBeAg-negative patients lost HBsAg, and no HBsAg seroreversion was observed. The 5-year cumulative Kaplan-Meier estimate for HBsAg loss was 17.2% for HBeAg-positive patients and 19.3% for HBeAg-negative patients. Fourteen of sixteen patients who lost HBsAg at any time point during follow-up developed anti-HBs antibodies (>10 IU/L). At year 5, in total 63% (20/32) of HBeAg-positive and 71% (27/38) of HBeAg-negative patients were retreated with nucleos(t)ide analogues during follow-up. The cumulative Kaplan-Meier estimate for retreatment was 60% of patients at year 5. At year 5 of follow-up, 18% of CHB patients treated with pegIFN/nucleotide analogue combination therapy had durable HBsAg loss and 88% of these had developed anti-HBs antibodies.

Are there ethical differences between stopping and not starting blood safety measures?

BACKGROUND AND OBJECTIVES: Concern with the costs of blood safety is growing, which raises the question whether safety measures that reduce risk only marginally should be discontinued. Withdrawing such safety measures would allow reallocating resources to more efficient health care interventions, but it might raise moral objections. MATERIALS AND METHODS: This study evaluates two ethical arguments why discontinuing blood safety measures would be more objectionable than not implementing them. The first argument is that whereas withdrawing protective measures causes harm to patients, not starting protective measures 'merely' omits to prevent harm. The second argument is that patients who benefit from protective measures are historically entitled to the continuation of those protective measures. RESULTS: Both arguments are unconvincing. There is only a weak causal connection between removing blood safety measures and harms that transfusion recipients suffer. Moreover, patients are not entitled to the continuation of protective measures that prove very inefficient, unless applying these protective measures rectifies past injustice towards them. CONCLUSION: Unless stronger ethical objections can be found, blood system operators and regulators should be more willing to withdraw inefficient safety measures.

Detection of parvovirus B19 DNA in blood: Viruses or DNA remnants?

BACKGROUND: Parvovirus B19 (B19V) DNA can be detected in blood over a long period after acute infection. Several reports associate the presence of B19V DNA with disease, irrespective of timing of the initial B19V infection. OBJECTIVES: This study aims to analyze the properties of B19V DNA in blood, differentiating between bare, non-infectious strands of DNA and B19V DNA in viable virions. STUDY DESIGN: Ten blood donors with asymptomatic acute B19V infection were followed and sampled up to 22 months after infection. The samples were treated with and without an endonuclease and tested for B19V DNA, to distinguish between DNA in virions and naked DNA. RESULTS: In the acute phase of infection, high levels of B19V DNA were detected, concurrent with B19V IgM antibodies. B19V DNA apparently was encapsidated, as indicated by resistance to endonuclease degradation. Subsequently, B19V DNA remained detectable for more than one year in all donors at low levels (<105 IU/mL). Approximately 150days after infection B19V DNA became degradable by an endonuclease, indicating that this concerned naked DNA. In some donors a second endonuclease-resistant peak occurred. DISCUSSION: Detection of B19V DNA in blood by PCR does not necessarily imply that B19V replication takes place and that infectious B19V virions are present. We propose that remnant B19V DNA strands can be released from tissues without active replication. This finding urges to reconsider an assumed role of B19V infection mainly based on B19V DNA detection in blood, a much debated subject in clinical syndromes such as myocarditis and arthritis.

Estimating the risk of dengue transmission from Dutch blood donors travelling to Suriname and the Dutch Caribbean.

BACKGROUND: The risk of dengue transmitted by travellers is known. Methods to estimate the transmission by transfusion (TT) risk from blood donors travelling to risk areas are available, for instance, the European Up-Front Risk Assessment Tool (EUFRAT). This study aimed to validate the estimated risk from travelling donors obtained from EUFRAT. METHODS: Surveillance data on notified dengue cases in Suriname and the Dutch Caribbean islands (Aruba, Curaçao, St. Maarten, Bonaire, St. Eustatius and Saba) in 2001-2011 was used to calculate local incidence rates. Information on travel and donation behaviour of Dutch donors was collected. With the EUFRAT model, the TT risks from Dutch travelling donors were calculated. Model estimates were compared with the number of infections in Dutch travellers found by laboratory tests in the Netherlands. RESULTS: The expected cumulative number of donors becoming infected during travels to Suriname and the Dutch Caribbean from 2001 to 2011 was estimated at 5 (95% CI, 2-11) and 86 (45-179), respectively. The infection risk inferred from the laboratory-based study was 19 (9-61) and 28 (14-92). Given the independence of the data sources, these estimates are remarkably close. The model estimated that 0·02 (0·001-0·06) and 0·40 (0·01-1·4) recipients would have been infected by these travelling donors. CONCLUSIONS: The EUFRAT model provided an estimate close to actual observed number of dengue infections. The dengue TT risk among Dutch travelling donors can be estimated using basic transmission, travel and donation information. The TT risk from Dutch donors travelling to Suriname and the Dutch Caribbean is small.

Identification of FDA-approved drugs that target hepatitis B virus transcription.

In the treatment of chronic hepatitis B virus (HBV) infection, polymerase inhibitors successfully suppress HBV DNA production. However, the production of viral proteins continues unhindered, which hampers viral clearance. Here, we screen for compounds that suppress HBV transcription, which would prevent viral protein production. A total of 640 FDA-approved drugs were evaluated for their ability to inhibit HBV transcription in a transfection-based HBV reporter assay. The assay was performed in the presence and absence of the HBV accessory protein X (HBx), which is essential for in vivo HBV RNA transcription. We observed that in the absence of HBx 47, and in the presence of HBx 24 compounds suppressed transcription by more than 20%. We selected the 24 most potent compounds in each condition for further analysis. On average, the selected compounds reduced transcription by 33.9% (range: 24.1-65.8%) in the absence of HBx expression, and 30.6% (range: 20.4-48.9%) in the presence of HBx. The two selections of 24 compounds had 12 compounds in common, resulting in a final selection of 36 compounds, which were evaluated for their capacity to suppress HBV replication in constitutively HBV-replicating HepG2.2.15 cells. Twenty-three of these compounds reduced HBV replication by interfering with RNA transcription. Further analysis revealed that one of the compounds, terbinafine, potently and specifically suppressed HBx-mediated HBV RNA transcription in HepG2 cells. Inhibition of HBV protein production is a promising step towards HBV clearance. In combination with an HBV polymerase inhibitor, the added suppression of HBV RNA transcription may markedly improve antiviral treatment outcome.

The estimated future disease burden of hepatitis C virus in the Netherlands with different treatment paradigms.

BACKGROUND & AIMS: Prevalence of hepatitis C virus (HCV) infection in the Netherlands is low (anti-HCV prevalence 0.22%). All-oral treatment with direct-acting antivirals (DAAs) is tolerable and effective but expensive. Our analysis projected the future HCV-related disease burden in the Netherlands by applying different treatment scenarios. METHODS: Using a modelling approach, the size of the HCV-viraemic population in the Netherlands in 2014 was estimated using available data and expert consensus. The base scenario (based on the current Dutch situation) and different treatment scenarios (with increased efficacy, treatment uptake, and diagnoses) were modelled and the future HCV disease burden was predicted for each scenario. RESULTS: The estimated number of individuals with viraemic HCV infection in the Netherlands in 2014 was 19,200 (prevalence 0.12%). By 2030, this number is projected to decrease by 4 5% in the base scenario and by 85% if the number of treated patients increases. Furthermore, the number of individuals with hepatocellular carcinoma and liver-related deaths is estimated to decrease by 19% and 27%, respectively, in the base scenario, but may both be further decreased by 68% when focusing on treatment of HCV patients with a fibrosis stage of ≥ F2. CONCLUSIONS: A substantial reduction in HCV-related disease burden is possible with increases in treatment uptake as the efficacy of current therapies is high. Further reduction of HCV-related disease burden may be achieved through increases in diagnosis and preventative measures. These results might inform the further development of effective disease management strategies in the Netherlands.

Frequent hepatitis E in the Netherlands without traveling or immunosuppression.

BACKGROUND AND OBJECTIVE: In several Western countries, silent endemic hepatitis E virus (HEV) infection is common among blood donors. Immunocompromised persons may develop chronic hepatitis E, but the relevance of endemic HEV for immunocompetent persons remains largely unknown. We investigated the immune status and travel history in cases of hepatitis E in the Netherlands. STUDY DESIGN: Between January 2009 and May 2014, physicians throughout the Netherlands submitted samples from 4067 hepatitis patients to Sanquin Diagnostic Services for HEV antibody testing. For the 144 patients testing positive for HEV IgM and HEV RNA, travel behavior and immune status were assessed. Complete information was obtained for 81 patients. RESULTS: Surprisingly, the majority of patients (52/81, 64%) were immunocompetent and did not travel outside Europe. HEV genotyping was obtained for 47 non-traveling patients, all concerned HEV genotype 3. DISCUSSION: Our findings suggest that currently in Western countries the impact of hepatitis E for non-traveling, immunocompetent persons is underestimated. Historically cases of hepatitis A, B and C, but not cases of hepatitis E, are notifiable and warrant preventive measures. However, in parts of Western Europe HEV may have become the most important source of viral hepatitis, in immunocompetent and in immunosuppressed persons. Pending measures against the ongoing transmission of HEV genotype 3 in parts of Europe, physicians should consider hepatitis E in dealing with new hepatitis patients.

Surface antigen-negative hepatitis B virus infection in Dutch blood donors.

Hepatitis B virus (HBV) surface antigen (HBsAg) is a reliable marker for HBV infection, but HBsAg-negative forms of HBV infection occur. The introduction of HBV DNA screening of Dutch blood donors, which were not preselected for absence of HBV core antibodies, enabled the characterization of HBsAg-negative HBV infection in healthy persons and a comparison of the HBV genomes involved. The screening of 4.4 million Dutch blood donations identified 23 HBsAg-negative, HBV DNA-positive persons. Serological testing of the index donations, follow-up samples and archived earlier samples was performed to determine the nature of each HBV DNA-only case. Despite low viral loads HBV DNA could be sequenced in 14 out of 23 donors, allowing HBV genotyping and the analysis of mutations in the HBV surface gene. Four types of HBsAg-negative HBV infection were detected: infection in the early stage before occurrence of HBsAg; suppressed infection after vaccination; HBV genotype G infection with decreased HBsAg production; and chronic occult (HBsAg negative) HBV infection. In the donors with occult HBV genotype D infection the HBV surface gene showed multiple "escape" mutations in the HBsAg a-determinant and CTL epitopes, while in an occult genotype A case the surface gene showed no mutations. HBsAg-negative forms of HBV infection in healthy blood donors explain the ongoing transmission of HBV via blood transfusion, if donor screening is limited to HBsAg. The screening of blood donors for HBV DNA and HBV core antibodies seems to cover all stages and variants of HBV infection.

Silent hepatitis E virus infection in Dutch blood donors, 2011 to 2012.

In Europe, the dynamics of endemic hepatitis E virus (HEV) infection remain enigmatic. We studied the presence of silent HEV infection among Dutch blood donors. Using donations collected throughout the Netherlands in 2011 and 2012, 40,176 donations were tested for HEV RNA in 459 pools of 48 or 480 donations. Deconstruction of the reactive pools identified 13 viraemic donors. In addition, 5,239 donors were tested for presence of anti-HEV IgG and IgM and for HEV RNA when IgM-positive. Of the 5,239 donations, 1,401 (27%) tested repeat-positive for HEV IgG, of which 49 (3.5%) also tested positive for anti-HEV IgM. Four of the HEV IgM-positive donors tested positive for HEV RNA. HEV IgG seroprevalence ranged from 13% among donors younger than 30 years to 43% in donors older than 60 years. The finding of 17 HEV RNA-positive donations among 45,415 donations corresponds to one HEV-positive blood donation per day in the Netherlands. For 16 of the 17 HEV RNA-positive donors, genotyping succeeded, revealing HEV genotype 3, which is circulating among Dutch pigs. Apparently, silent HEV infection is common in the Netherlands, which possibly applies to larger parts of Europe.

The yield of temporary exclusion of blood donors, exposed to emerging infections abroad.

BACKGROUND AND OBJECTIVES: Emerging infections abroad pose a threat to the safety of blood, donated by travelling blood donors. In this study, the yield of donor deferral after travelling was evaluated, by comparing the estimated numbers of infected donors returning from various affected areas. METHODS: A deterministic model was applied to calculate the number of infected donors, returning from six areas affected by outbreaks: Greece - Macedonia (West Nile fever), Italy - Emilia Romagna (West Nile fever), Thailand (chikungunya), Latvia (hepatitis A), central Turkey (Sicilian sandfly fever) and Italy - Tuscany (Toscana sandfly fever). RESULTS: The estimated number of infections among returning blood donors was surprisingly low, ranging from 0·32 West Nile virus-infected donors per year returning from Macedonia (Greece) to approximately 0·005 infected donors per year returning respectively from Tuscany (sandfly fever), Latvia (hepatitis A) and central Turkey (sandfly fever). CONCLUSION: The yield of the temporary exclusion of blood donors travelling to a specific, affected area is low, but the continuous monitoring of emerging infections and the timely assessment of new threats are laborious and imperfect. Safety measures may be instituted after the greatest threat of a new outbreak has passed. A general deferral of travelling donors may be more appropriate than targeted measures. It can be argued that all donors who stayed outside their country or continent of residency should be deferred for 4 weeks.

Chronic hepatitis E after solid organ transplantation.

Large outbreaks of acute hepatitis E, caused by hepatitis E virus (HEV) genotypes 1 and 2, are known from developing countries with suboptimal sanitation infrastructure. An increasing incidence of HEV infections is being reported in industrialised countries, caused mainly by HEV genotypes 3 and 4, which are often found among pigs. Recent evidence suggests that in immunocompromised patients about 50% of the cases of acute hepatitis E evolve to chronic hepatitis with rapid progression to cirrhosis. Thus, HEV should be considered a cause of chronic hepatitis in immunocompromised patients, such as solid organ transplant recipients. Because an antibody response to HEV may be absent in these patients, an HEV RNA test should be carried out when serum liver tests are elevated over months. In small case series, ribavirin has been shown to represent a promising treatment option for chronic HEV infection. To increase the awareness for HEV infection in immunocompromised patients, a representative case report of an HEV-infected renal transplant recipient with chronic hepatitis E, successfully treated with ribavirin, is presented. Studies are required to determine the optimal duration of ribavirin therapy and to assess outcome for solid organ transplant recipients with chronic HEV infection.

Detection of phase I IgG antibodies to Coxiella burnetii with EIA as a screening test for blood donations.

The presence of a high phase I IgG antibody titre may indicate chronic infection and a risk for the transmission of Coxiella burnetii through blood transfusion. The outbreak of Q fever in the Netherlands allowed for the comparison of an enzyme immunoassay (EIA) with the reference immunofluorescence assay (IFA) in a large group of individuals one year after acute Q fever. EIA is 100 % sensitive in detecting high (≥1:1,024) phase I IgG antibody titres. The cost of screening with EIA and confirming all EIA-positive results with IFA is much lower than screening all donations with IFA. This should be taken into account in cost-effectiveness analyses of screening programmes.

Relation between Q fever notifications and Coxiella burnetii infections during the 2009 outbreak in The Netherlands.

Large outbreaks of Q fever in the Netherlands from 2007 to 2009 were monitored using notification data of acute clinical Q fever. However, the notification system provides no information on infections that remain subclinical or for which no medical attention is sought. The present study was carried out immediately after the peak of the 2009 outbreak to estimate the ratio between Coxiella burnetii infections and Q fever notifications. In 23 postcode areas in the high-incidence area, notification rates were compared with seroconversion rates in blood donors from whom serial samples were available. This resulted in a ratio of one Q fever notification to 12.6 incident infections of C. burnetii. This ratio is time and place specific and is based on a small number of seroconversions, but is the best available factor for estimating the total number of infections. In addition, as subclinical C. burnetii infection may lead to chronic Q fever, the ratio can be used to estimate the expected number of chronic Q fever patients in the coming years and as input for cost­benefit analyses of screening options.