Regina Allwinn

Influenza Vaccination Compliance Among Health Care Workers in a German University Hospital

Background:Since 1988, the Standing Committee on Vaccination (STIKO) at the Robert Koch-Institute, Berlin, has explicitly recommended that health-care workers (HCWs) should be vaccinated against seasonal influenza. However, acceptance of the influenza vaccination by medical personnel is low.Methods:This study analyzes factors associated with the compliance of HCWs with the seasonal influenza vaccination on the basis of three different anonymized questionnaires during two consecutive influenza seasons: 2006/2007 and 2007/2008. The questionnaires covered details of demographics, frequency of previous vaccinations, reasons for accepting or declining the vaccination, and the HCW’s knowledge of the influenza vaccine and influenza itself.Results:Our study showed that physicians were significantly more likely to have been vaccinated than nurses (38.8% vs 17.4%; p < 0.0001). The main reasons for noncompliance included: supposition of a low risk of infection, fear of side effects, the belief that the influenza vaccine might trigger the influenza virus infection, and scepticism about the effectiveness of the influenza vaccination.Conclusion:Our findings confirm the importance of a comprehensive approach to the vaccination, ensuring that HCWs are correctly informed about the vaccine and that it is convenient to receive it.

Immune Response after Two Doses of the Novel Split Virion, Adjuvanted Pandemic H1N1 Influenza A Vaccine in HIV-1–Infected Patients

BACKGROUND To determine the rate of seroconversion after 2 doses of a novel split virion, inactivated, adjuvanted pandemic H1N1 influenza vaccine (A/California/7/2009) in human immunodeficiency virus type 1 (HIV-1)-infected patients (ClinicalTrials.gov NCT01017172). METHODS Diagnostic study of adult HIV-1-infected patients scheduled for H1N1 influenza A vaccination. Blood samples where taken before and 21 days after the first dose and 21 days after the second dose of the vaccine. Antibody (AB) titers were determined by hemagglutination inhibition assay. Seroconversion was defined by either an AB titer ≤ 1:10 before and ≥ 1:40 after or ≥ 1:10 before and a ≥ 4-fold increase in AB titer 21 days after vaccination. RESULTS One hundred thirty-five patients received 2 doses of the H1N1 vaccine and were analyzed. The rate of seroconversion was 68.2% (95% confidence interval, 59.6-75.9) after the first dose and 91.9% (95% confidence interval, 85.9-95.9) after the second dose. Patients who did not seroconvert had a lower mean nadir CD4 cell count (± standard deviation; 81 ± 99 vs 190 ± 148 cells/μL; P = .006), had a longer duration of HIV infection (± standard deviation; 13.1 ± 5.9 vs 8.8 ± 6.8 years; P = .04), and were more likely to have an AB titer ≥ 1:40 before vaccination (4% vs 55%; P < .001) when compared with patients with seroconversion. No other differences were found between the 2 groups, including AIDS status, highly active antiretroviral therapy status, HIV RNA - polymerase chain reaction load <50 copies/mL, CD4 cell count, sex, body mass index, and chronic hepatitis. CONCLUSION Among HIV-infected patients, the rate of seroconversion after the first dose of an adjuvanted H1N1 influenza A vaccine was 68% and increased to 92% after a second doses.

Low rate of seroconversion after vaccination with a split virion, adjuvanted pandemic H1N1 influenza vaccine in HIV-1-infected patients.

Objective:To determine rates of seroconversion after single vaccination with a novel split virion, inactivated, adjuvanted pandemic H1N1 influenza vaccine (A/California/7/2009) in HIV-1-infected patients (ClinicalTrials.gov Identifier: NCT01017172). Design:Single center diagnostic study. Setting:Institutional HIV outpatient department of an urban university clinic. Participants:Adult HIV-1-infected individuals. Intervention:Serum samples were taken before and 21 days after vaccination. Main outcome measures:Antibody titers determined by hemagglutination inhibition assay. Seroconversion to vaccination was defined by either an antibody titer of 1: 10 or less before and of at least 1: 40 after or at least 1: 10 before and at least four-fold increase in antibody titer 21 days after single vaccination. Results:One hundred and sixty patients (125 men/35 women) were analyzed. Before vaccination, 23 patients (14.4%) had a hemagglutination inhibition assay titer of at least 1: 40. A median of 22 ± 3 days after vaccination, 110 (69%) patients seroconverted. Seroconverters were younger (45.1 ± 10.0 vs. 48.8 ± 11.3 years; P = 0.04), had a higher CD4 cell count (532 ± 227 vs. 475 ± 281 cells/μl; P = 0.03) and were more likely to have received a previous H5N1 vaccination in 2009 (25 vs. 8%; P = 0.02) when compared to nonresponders. No other significant differences were found comparing the two groups (prevaccination hemagglutination inhibition assay titer of ≥1: 40, AIDS, HAART, HIV RNA PCR <50 copies/ml or CD4 nadir, CD4 and CD8 percentage, sex, BMI, chronic hepatitis B or C). Conclusion:Seroconversion after one dose of a split virion, inactivated, adjuvanted pandemic H1N1 influenza vaccine of HIV-infected patients was 69%. Studies to investigate whether a second dose of the vaccine will increase seroconversion rate are needed.

Low vitamin D serum concentration is associated with high levels of hepatitis B virus replication in chronically infected patients

Vitamin D is an important immune modulator that plays an emerging role in inflammatory and metabolic liver diseases, including infection with hepatitis C virus (HCV). In contrast, the relationship between vitamin D metabolism and chronic hepatitis B (CHB) is less well characterized. Therefore, we quantified 25(OH)D3 serum levels in a cohort of 203 treatment‐naïve patients with chronic hepatitis B virus (HBV) infection and tested for their association with clinical parameters of CHB. Of 203 patients, 69 (34%), 95 (47%), and 39 (19%) had severe vitamin D deficiency (25(OH)D3 <10 ng/mL), vitamin D insufficiency (25(OH)D3 ≥10 and <20 ng/mL), or adequate vitamin D serum levels (25(OH)D3 ≥20 ng/mL), respectively. In both uni‐ and multivariate analyses, HBV DNA viral load (log10 IU/mL) was a strong predictor of low 25(OH)D3 serum levels (P = 0.0007 and P = 0.000048, respectively) and vice versa. Mean 25(OH)D3 serum concentrations in patients with HBV DNA <2,000 versus ≥2,000 IU/mL were 17 versus 11 ng/mL, respectively (P < 0.00001). In addition, hepatitis B early antigen (HBeAg)‐positive patients had lower 25(OH)D3 serum levels than HBeAg‐negative patients (P = 0.0013). Finally, 25(OH)D3 and HBV DNA serum levels showed inverse seasonal fluctuations. Conclusion: Low 25(OH)D3 serum levels are associated with high levels of HBV replication in patients with CHB. This represents a major difference from chronic hepatitis C, where numerous previous studies have shown a lack of correlation between HCV viral load and vitamin D serum levels. Inverse seasonal fluctuations of 25(OH)D3 and HBV DNA serum levels are suggestive of a functional relationship between both variables. (Hepatology 2013;58:1270–1276)

Cross-reactivity in flavivirus serology: new implications of an old finding?

Abstract.To investigate the influence of pre-existing antibodies against tick-borne encephalitis (TBE) or yellow fever (YF) viruses on dengue virus antibody test results, we examined sera from vaccinees and from individuals with previous TBE virus infection. Distinct IgG antibody cross-reactivity was found in about 15.1% in the YF-vaccinated group and in about 9.5% in the TBE-vaccinated group. Altogether 15 out of a total of 80 samples tested (18.8%) had detectable dengue virus IgG antibody titres. The serum samples from patients with acute TBE virus infection not only had the highest anti-TBE virus antibodies but were also highly cross-reactive against dengue virus antigens. The high cross-reactivity rate of YF and TBE antibody-positive sera in dengue virus antibody assays should be taken into account in the interpretation of laboratory tests for the diagnosis of flavivirus infections and when undertaking seroepidemiological surveys.

Viral Zoonoses – A Threat under Control?

Despite intensive research and considerable effort to eradicate infectious diseases, modern medicine has failed to control many infectious diseases which have been thought to be easy to overcome with advances in medical science and technology. In fact, infectious diseases remain a dominant feature in public health considerations for the 21st century. Some infectious agents already known to be pathogenic have gained increasing importance in recent decades due to changes in disease patterns. Furthermore, many new, previously unknown infectious agents with a high pathogenic potential have been identified. Nearly all of these emergent disease episodes have involved zoonotic or species-jumping infectious agents. The complex interaction of factors like environmental and ecological changes, social factors, decline of health care, human demographics and behaviour influences the emergence of re-emergence of such diseases. Viruses, especially RNA viruses with their ability to adapt quickly to changing environmental conditions, are among the most prominent examples of emerging pathogens. In this review, we present the important examples of zoonotic viruses and discuss the factors playing a key role in the emergence and resurgence of these diseases.

Clinical utility of the ARCHITECT HCV Ag assay for early treatment monitoring in patients with chronic hepatitis C genotype 1 infection

BACKGROUND Virologic response-monitoring is essential for determining therapy duration in patients with chronic hepatitis C virus (HCV) infection. This is usually performed using highly sensitive HCV-RNA assays. However, HCV-RNA assays are time-consuming, expensive and require highly trained personnel. Quantitative determination of HCV core-antigen (HCVAg) levels may be used to supplement treatment monitoring. OBJECTIVES The clinical utility of the ARCHITECT HCV Ag assay (Abbott Diagnostics) for response-guided therapy was investigated. STUDY DESIGN We analyzed serum from 160 patients with HCV genotype 1 infection who had been treated with peg-interferon alfa-2b/ribavirin. HCVAg levels were determined at baseline, weeks 1, 2, 4 and 12. HCVAg levels were compared to those obtained with HCV-RNA assays: VERSANT HCV Quantitative 3.0 (bDNA) and Qualitative (TMA, both Siemens Healthcare) assay and the Abbott RealTime HCV assay (ART; Abbott Diagnostics). RESULTS Baseline HCVAg levels correlated well with HCV-RNA as assessed by bDNA (r=0.91; p<0.0001) and ART (r=0.92; p<0.0001), respectively. Patients with undetectable HCVAg levels at week 1 had a 90.9% probability (positive predictive value) to achieve a rapid virologic response (HCV-RNA undetectable at week 4) based on TMA and 86.4% based on ART, respectively. Patients with less than 1 log(10) reduction in HCVAg between baseline and week 12 had a 90% probability (negative predictive value) to achieve a nonresponse (<2 log(10) decline in HCV-RNA between baseline and week 12) based on bDNA and 100% based on ART, respectively. CONCLUSIONS Determination of HCVAg may be useful for antiviral response-monitoring in patients with HCV genotype 1 infection.

Human cytomegalovirus infection in tumor cells of the nervous system is not detectable with standardized pathologico-virological diagnostics

BACKGROUND Experimental findings have suggested that human cytomegalovirus (HCMV) infection of tumor cells may exert oncomodulatory effects that enhance tumor malignancy. However, controversial findings have been published on the presence of HCMV in malignant tumors. Here, we present the first study that systematically investigates HCMV infection in human nervous system tumors by highly sensitive immunohistochemistry in correlation with the HCMV serostatus of the patients. METHODS Immunohistochemical and quantitative PCR-based methods to detect different HCMV antigens and genomic HCMV DNA were optimized prior to the investigation of pathological samples. Moreover, the pathological results were matched with the HCMV serostatus of the patients. RESULTS HCMV immediate-early, late, and pp65 antigens could be detected in single cells from HCMV strain Hi91-infected UKF-NB-4 neuroblastoma cells after 1:1024 dilution with noninfected UKF-NB-4 cells. Genomic HCMV DNA could be detected in copy numbers as low as 430 copies/mL. However, we did not detect HCMV in tumors from a cohort of 123 glioblastoma, medulloblastoma, or neuroblastoma patients. Notably, we detected nonspecifically positive staining in tumor tissues of HCMV seropositive and seronegative glioblastoma patients. The HCMV serostatus of 67 glioblastoma patients matched the general epidemiological prevalence data for Western countries (72% of female and 57% of male glioblastoma patients were HCMV seropositive). Median survival was not significantly different in HCMV seropositive versus seronegative glioblastoma patients. CONCLUSIONS The prevalence of HCMV-infected tumor cells may be much lower than previously reported based on highly sensitive detection methods.

Enhanced Immune Response after a Second Dose of an AS03-Adjuvanted H1N1 Influenza A Vaccine in Patients after Hematopoietic Stem Cell Transplantation

Seroconversion rates following influenza vaccination in patients with hematologic malignancies after hematopoietic stem cell transplantation (HSCT) are known to be lower compared to healthy adults. The aim of our diagnostic study was to determine the rate of seroconversion after 1 or 2 doses of a novel split virion, inactivated, AS03-adjuvanted pandemic H1N1 influenza vaccine (A/California/7/2009) in HSCT recipients (ClinicalTrials.gov Identifier: NCT01017172). Blood samples were taken before and 21 days after a first dose and 21 days after a second dose of the vaccine. Antibody (AB) titers were determined by hemagglutination inhibition assay. Seroconversion was defined by either an AB titer of ≤ 1:10 before and ≥ 1:40 after or ≥ 1:10 before and ≥ 4-fold increase in AB titer 21 days after vaccination. Seventeen patients (14 allogeneic, 3 autologous HSCT) received 1 dose and 11 of these patients 2 doses of the vaccine. The rate of seroconversion was 41.2% (95% confidence interval [CI] 18.4-67.1) after the first and 81.8% (95% CI 48.2-97.7) after the second dose. Patients who failed to seroconvert after 1 dose of the vaccine were more likely to receive any immunosuppressive agent (P = .003), but time elapsed after or type of HSCT, age, sex, or chronic graft-versus-host disease was not different when compared to patients with seroconversion. In patients with hematologic malignancies after HSCT the rate of seroconversion after a first dose of an adjuvanted H1N1 influenza A vaccine was poor, but increased after a second dose.

Significant increase in travel-associated dengue fever in Germany.

Increasing numbers of dengue fever (DF) cases reflect the increasing travel mobility together with the expanding geographical distribution of the vector Aedes aegypti. Compared with earlier surveys in Germany, higher incidences occur and correlate well with ongoing outbreaks. Therefore, we investigated 767 serum samples from 594 returning travellers with suspected DF between 2005 and 2010, which where sent from different hospitals in the drainage area Frankfurt/Main. Established diagnostic assays were ELISA, immunofluorescence and chromatographic tests. We obtained 112 dengue-seropositive serum samples from totally 60 patients: the detection rate was 10.1% (60 out of 594). A significant increase was found in 2010. Most patients were aged between 40 and 49, and indirect immunofluorescence technique indicated mainly DF serotype 2. Actual data reveal a significant rise in imported DF cases in 2010 according to an increasing risk to acquire DF virus infection. Nevertheless, dengue haemorrhagic fever and dengue shock syndrome are still rare in travellers, but those with a history of dengue should be tested for DF serotypes and advised to protect themselves well from mosquitoes when travelling to endemic areas.