Airborne Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Hospitals: Effects of Aerosol-Generating Procedures, HEPA-Filtration Units, Patient Viral Load, and Physical Distance.

BACKGROUND: Transmission of coronavirus disease 2019 (COVID-19) can occur through inhalation of fine droplets or aerosols containing infectious virus. The objective of this study was to identify situations, patient characteristics, environmental parameters, and aerosol-generating procedures (AGPs) associated with airborne severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. METHODS: Air samples were collected near hospitalized COVID-19 patients and analyzed by RT-qPCR. Results were related to distance to the patient, most recent patient diagnostic PCR cycle threshold (Ct) value, room ventilation, and ongoing potential AGPs. RESULTS: In total, 310 air samples were collected; of these, 26 (8%) were positive for SARS-CoV-2. Of the 231 samples from patient rooms, 22 (10%) were positive for SARS-CoV-2. Positive air samples were associated with a low patient Ct value (OR, 5.0 for Ct <25 vs >25; P = .01; 95% CI: 1.18-29.5) and a shorter physical distance to the patient (OR, 2.0 for every meter closer to the patient; P = .05; 95% CI: 1.0-3.8). A mobile HEPA-filtration unit in the room decreased the proportion of positive samples (OR, .3; P = .02; 95% CI: .12-.98). No association was observed between SARS-CoV-2-positive air samples and mechanical ventilation, high-flow nasal cannula, nebulizer treatment, or noninvasive ventilation. An association was found with positive expiratory pressure training (P < .01) and a trend towards an association for airway manipulation, including bronchoscopies and in- and extubations. CONCLUSIONS: Our results show that major risk factors for airborne SARS-CoV-2 include short physical distance, high patient viral load, and poor room ventilation. AGPs, as traditionally defined, seem to be of secondary importance.

Absence of interferon-λ 4 enhances spontaneous clearance of acute hepatitis C virus genotypes 1-3 infection.

OBJECTIVES: Absence of a functional interferon-λ 4 (IFN-λ4) gene (IFNL4) predicts spontaneous resolution of acute hepatitis C virus (HCV) infections in regions with a predominance of genotype 1, whereas variants of the inosine triphosphate pyrophosphatase (ITPase) gene (ITPA) entailing reduced activity associate with increased sustained virologic response rates following some therapeutic regimens. This study aimed at investigating the impact of IFNL4 on acute HCV genotype 2 or 3 infections, and whether ITPase activity influenced outcome. MATERIALS AND METHODS: Two hundred and seven people who injected drugs (PWID) with documented anti-HCV seroconversion, and 57 PWID with reinfection with HCV were analyzed regarding IFNL4 (rs368234815 and rs12979860) and ITPA (rs1127354 and rs7270101), and longitudinally followed regarding HCV RNA. RESULTS: The spontaneous clearance of HCV infection in anti-HCV seronegative PWID was enhanced when IFN-λ4 was absent (44% vs. 20% for IFNL4 TT/TTrs1368234815 and ΔGrs1368234815 respectively, p < .001; OR 3.2) across genotypes 1-3. The proportion lacking IFN-λ4 was further increased following resolution of repeated re-exposure to HCV (74% among re-infected participants who had cleared at least two documented HCV infections). ITPA genetic variants did not independently impact on the outcome, but among males lacking IFN-λ4, reduced ITPase activity markedly augmented the likelihood of resolution (65% vs. 29% for <100% and 100% ITPase activity, p = .006). CONCLUSIONS: Absence of IFN-λ4 entails an enhanced likelihood of spontaneous resolution both following primary acute infection and repeated re-exposure to HCV across genotypes 1-3. Among men lacking IFN-λ4, reduced ITPase activity improved outcome.

Sources of Airborne Norovirus in Hospital Outbreaks.

BACKGROUND: Noroviruses are the major cause of viral gastroenteritis. Disease transmission is difficult to prevent and outbreaks in health-care facilities commonly occur. Contact with infected persons and contaminated environments are believed to be the main routes of transmission. However, noroviruses have recently been found in aerosols and airborne transmission has been suggested. The aim of our study was to investigate associations between symptoms of gastroenteritis and the presence of airborne norovirus, and to investigate the size of norovirus-carrying particles. METHODS: Air sampling was repeatedly performed close to 26 patients with norovirus infections. Samples were analyzed for norovirus RNA by reverse transcription quantitative polymerase chain reaction. The times since each patient's last episodes of vomiting and diarrhea were recorded. Size-separating aerosol particle collection was performed. RESULTS: Norovirus RNA was found in 21 (24%) of 86 air samples from 10 different patients. Only air samples during outbreaks, or before a succeeding outbreak, tested positive for norovirus RNA. Airborne norovirus RNA was also strongly associated with a shorter time period since the last vomiting episode (odds ratio 8.1; P = .04 within 3 hours since the last vomiting episode). The concentrations of airborne norovirus ranged from 5-215 copies/m3, and detectable amounts of norovirus RNA were found in particles <0.95 µm and >4.51 µm. CONCLUSIONS: The results suggest that recent vomiting is the major source of airborne norovirus and imply a connection between airborne norovirus and outbreaks. The presence of norovirus RNA in submicrometre particles indicates that airborne transmission can be an important transmission route.

Prediagnostic serum polychlorinated biphenyl concentrations and primary liver cancer: A case-control study nested within two prospective cohorts.

BACKGROUND: Polychlorinated biphenyls (PCBs) were used in electrical equipment and a range of construction materials. Although banned in the United States and most of Europe in the 1970s, they are highly persistent in the environment and bioaccumulate. Whether PCBs are associated with liver cancer risk at general population levels is unknown. METHODS: This study consisted of 136 incident liver cancer cases and 408 matched controls from the Kaiser Permanente Northern California Multiphasic Health Checkup (MHC) cohort and 84 cases and 252 matched controls from the Norwegian Janus cohort. Sera collected in the 1960s-1980s were measured for 37 PCB congeners and markers of hepatitis B (HBV) and C (HCV) infection. Odds ratios (OR) and 95% confidence intervals (CI) for tertiles of each lipid-adjusted PCB were estimated from conditional logistic regression. We also examined the molar sum of congeners in groups: total PCBs; low, medium, and high chlorination; and Wolff functional groups. RESULTS: Concentrations of individual congeners from the 1960s/1970s sera ranged from 1.3-123.0 and 1.4-116.0 ng/g lipid among MHC cases and controls, respectively, and from 1.9-258.0 and 1.9-271.0 ng/g lipid among Janus cases and controls, respectively. Among MHC participants with sera from the 1960s, collected an average of 27 years before diagnosis among cases, the top tertile of PCBs 151, 170, 172, 177, 178, 180, and 195 was significantly associated with elevated odds of liver cancer (OR range = 2.01-2.38); most of these congeners demonstrated exposure-response trends. For example, ORtertile 3vs1 = 2.38 (95% CI: 1.22-4.64, p-trend = 0.01) for PCB 180. As a group, Wolff group 1b congeners, which are biologically persistent and weak phenobarbital inducers, were associated with increased odds. In MHC participants, ever vs. never HBV or HCV infection modified the PCB-liver cancer associations. There was little evidence of an association between PCBs and odds of liver cancer among the Janus cohort. DISCUSSION: We observed associations between a number of PCB congeners and increased odds of liver cancer among MHC, but not Janus, participants with sera from the 1960s/1970s.

Prediagnostic serum organochlorine insecticide concentrations and primary liver cancer: A case-control study nested within two prospective cohorts.

Although experimental evidence indicates that certain organochlorine insecticides are hepatocarcinogens, epidemiologic evidence for most of these chemicals is very limited. We estimated associations, using prospectively collected sera, between organochlorine insecticide concentrations and cancer registry-identified primary liver cancer in two cohorts, one from the United States and one from Norway. In nested case-control studies, we used sera collected in the 1960s-1980s from 136 cases and 408 matched controls from the Kaiser Permanente Northern California Multiphasic Health Checkup (MHC) cohort and 84 cases and 252 matched controls from the population-based Norwegian Janus cohort. We measured concentrations of nine organochlorine insecticides/metabolites and markers of hepatitis B and C in sera. Adjusted odds ratios (OR) and 95% confidence intervals (CI) for tertiles of lipid-corrected organochlorines were calculated for each cohort using conditional logistic regression. Among MHC participants with sera from the 1960s, there was a suggestive exposure-response trend for trans-nonachlor (second and third tertile of analyte ORs = 1.63 and 1.95, respectively; p-trend = 0.08) and a nonsignificantly elevated risk for the highest tertile of oxychlordane (OR = 1.87). Among Janus participants with sera from the 1970s, we observed an apparent trend for p,p'-DDT (second and third tertile ORs = 1.70 and 2.14, respectively; p-trend = 0.15). We observed little consistency in patterns of association between the cohorts. We found limited evidence that exposure to p,p'-DDT and chlordane-related oxychlordane and trans-nonachlor may be associated with increased risk of primary liver cancer. However, the modest strength of these associations and their lack of concordance between cohorts necessitate caution in their interpretation.

Chronic hepatitis C in Swedish subjects receiving opiate substitution therapy--factors associated with advanced fibrosis.

BACKGROUND: Opiate substitution therapy (OST) reduces the risk of death from directly drug-related causes in heroin users, allowing other chronic health problems to emerge. People who inject drugs (PWID) are exposed to hepatitis C virus (HCV), with an associated risk of chronic liver disease. We investigated HCV prevalence and liver-related morbidity in a cohort of OST recipients, and analyzed factors associated with significant hepatic fibrosis. METHODS: All patients registered on 1 April 2008 in 4 clinics providing OST in the 3 largest cities in Sweden were eligible for inclusion. HCV viremic subjects were evaluated for fibrosis stage by liver biopsy, transient elastometry (TE), and/or a biochemical fibrosis index (Göteborg University Cirrhosis Index; GUCI). Factors associated with severity of fibrosis were determined by logistic regression analysis. RESULTS: Out of 524 eligible patients, 277 consented to enrolment. Two hundred and thirty-six subjects (88%) were anti-HCV-positive, and 162 of these were viremic (69%). Significant liver fibrosis (defined as Ishak stages F3-F6, TE value ≥ 8.85 kPa, or GUCI > 0.33) was found in 69 out of 103 (67%) tested viremic patients, and was associated with alcohol intake (p = 0.03), higher body mass index (BMI; p = 0.04), and the presence of anti-HBc antibodies (indicating exposure to hepatitis B virus (HBV); p = 0.02). CONCLUSIONS: Significant liver fibrosis was detected in two-thirds of HCV viremic OST recipients in this cohort, and was associated with alcohol use, high BMI, and exposure to HBV. These findings indicate that the management of HCV and associated risk factors should be emphasized in Swedish OST programs.

Viral aetiology and clinical outcomes in hospitalised infants presenting with respiratory distress.

AIM: To determine the prevalence of various types of viruses in infants hospitalised due to respiratory distress, compare molecular diagnostic tests and evaluate symptom severity. METHODS: All 136 nasopharyngeal aspirates from infants hospitalised for respiratory distress over a 9-month period were analysed for virus type by in-house respiratory syncytial virus (RSV) polymerase chain reaction (PCR) microarray-based and/or Luminex-based multiplex molecular tests. Medical records were reviewed retrospectively for clinical data. RESULTS: Viral aetiology was confirmed in 126 subjects (92.6%) with 26 infected by more than one virus. RSVA/B was the most common (50.9%), followed by entero/rhinovirus (21.6%), human metapneumovirus (10.5%), parainfluenza virus (5.9%) and influenza (3.3%). RSV-infected infants had significantly lower saturation levels (89% versus 92%, p < 0.001), higher demand for oxygen (42.7% versus 21.6%, p = 0.021) and fluids (28% versus 9.8%; p = 0.014) and longer hospital stays (4 versus 3 days, <0.001) than other viruses. Luminex assays gave repeatable, slightly less sensitive results than in-house RSV PCR. Microarray-based assays were more sensitive, however, producing some unrepeatable results. CONCLUSION: Respiratory syncytial virus dominates as the viral cause in hospitalised infants with respiratory distress in Sweden during the winter season, resulting in a clinical course that is significantly more severe. The multiplex assays produced reasonably concordant results.

The risk of cancer among persons with a history of injecting drug use in Sweden - a cohort study based on participants in a needle exchange program.

BACKGROUND: Injecting drug use (IDU) may lead to exposure to a range of carcinogenic agents. We investigated the risk and distribution of cancers among individuals with a history of IDU in Sweden. MATERIAL AND METHODS: The cancer incidence in a cohort of longitudinally followed participants in a needle exchange program (NEP), recruited between 1987 and 2007, was compared to that in the Swedish general population, matching for age group and gender. Baseline demographic and drug use data were collected and longitudinal testing of serological markers for HIV, hepatitis B and C virus was performed during NEP participation. Standardized incidence ratios (SIR) for types of cancer found in the study cohort were calculated, using data from the Swedish National Cancer Registry for reference. RESULTS: The mean follow-up time for the 3255 participants was 11.8 years, constituting 38 419 person years at risk. The mean age at end of follow-up was 42.7 years, and 75% of participants were men. Seventy-eight cases of cancer were observed (SIR 1.1 [95% CI = 0.9-1.4]). The SIR was significantly increased for five cancer types among men; primary liver, laryngeal, lung, oropharyngeal and non-melanoma skin cancer (respective SIR 12.8 [95% CI = 4.2-30.0], 9.2 [95% CI = 1.9-26.8], 3.2 [95% CI = 1.5-6.1], 7.3 [95% CI = 1.5-21.2], and 3.5 [95% CI = 1.1-8.2]), and for cancers of endocrine organs among women (5.3 [95% CI = 1.7-12.4]). CONCLUSION: Although the standardized overall cancer incidence in this relatively young IDU cohort was similar to that in the general population, the risk of specific types of cancer was significantly increased, suggesting that IDU confers elevated risks for certain malignancies. These findings prompt further studies to investigate causative factors and suggest the need for surveillance among persons with a history of IDU.

Monitoring hepatitis C infection in a major Swedish nephrology unit and molecular resolution of a new case of nosocomial transmission.

Hepatitis C virus (HCV) infection is a frequent problem in hemodialysis units. The prevalence and incidence of HCV infection over a decade were studied in a nephrology unit affected by previous nosocomial HCV transmission. The HCV non-structural 5B protein gene was sequenced to achieve phylogenetic analysis of a new (incident) case of infection. Proportions of patients who were and were not infected with HCV remained similar over the period, as did the inflow and outflow of patients infected previously. In 1997, 12/157 (8%) of patients at the unit (treatment: hemodialysis, peritoneal dialysis, and renal transplant recipients) were positive in HCV RNA, whereas in 2007 the overall number was 9/239 (4%). One patient acquired an HCV infection, and the NS5B sequence in that case clustered with genotype 2b sequences found in patients from an earlier outbreak. Comparing the HCV from the incident patient with several stored longitudinal samples and cloned PCR products from the most likely source patient revealed close phylogenetic relationship with an HCV quasispecies member from the possible source. The source patient and the incident newly infected patient were not scheduled on the same dialysis shift, although the records showed that simultaneous treatment occurred on two occasions during the months preceding transmission. In conclusion, over the 10-year period, the proportion of HCV-infected patients at the unit was unchanged. Only one new infection occurred, which originated from a fellow patient's quasispecies. This establishes phylogenetic analysis as a valuable tool for tracing patient sources of HCV transmission.

Clinical severity of Mycoplasma pneumoniae (MP) infection is associated with bacterial load in oropharyngeal secretions but not with MP genotype.

BACKGROUND: Disease severity in Mycoplasma pneumoniae (MP) infection could potentially be related to bacterial factors such as MP genotype (MP1 or MP2; distinguished by different adhesions proteins) or bacterial load in airway secretions. We have compared these parameters in patients who were hospitalized for MP pneumonia, with outpatients with mild MP disease. METHODS: MP bacterial load was measured by real-time PCR in 45 in- and outpatients ("clinical study group") in whom MP DNA had been detected in oropharyngeal secretions by PCR. In addition, genotype and phylogenetic relationships were determined. The phylogenetical assessment was done by partial DNA sequencing of the P1 gene on isolates from 33 patients in the clinical study-group where sufficient DNA was available. The assessment was further extended to isolates from 13 MP-positive family members and 37 unselected MP positive patients from the two subsequent years and two different geographical locations. In total 83 strains were molecular characterized. RESULTS: Mean MP loads were significantly higher in 24 hospitalized patients than in 21 outpatients (1600 vs. 170 genomic equivalents/microL, p = 0.009). This difference remained significant after adjustment for age and days between disease onset and sampling. Hospitalized patients also had higher C-reactive protein levels. Mean levels were 188 vs 20 mg/L (p = 0,001). The genotype assessment showed MP genotype 1 in 17 of the 33 sequenced strains from the clinical study-group, and type 2 in 16 of these patients. Within each genotype, sequence differences were minimal. No association between disease severity and MP genotype was observed. In the extended genotype assessment, MP1 was found in similar proportions. In family contacts it was found in 53% and among patients from the two subsequent years 53% and 40%. CONCLUSIONS: A higher MP bacterial load in throat secretions at diagnosis was associated with more advanced respiratory disease in patients, but MP genotype did not influence disease severity. Both MP genotypes co-circulated during recent outbreaks in Sweden.

Longitudinal clearance of seasonal influenza A viral RNA measured by real-time polymerase chain reaction in patients identified at a hospital emergency department.

To study influenza virus shedding during acute infection, viral load was longitudinally measured by quantitative PCR in nasal flocked swabs from patients with seasonal H3N2 influenza at a Swedish emergency department, including both hospitalized patients and outpatients. Influenza A was detected in 65/184 patients. Sampling was repeated every 3-4 days in 45 patients, with the aim of continuing sampling until day 12 after disease onset. Home visits were offered. Antibodies were measured on paired sera in 95/184 patients. Fifty percent of the patients remained polymerase chain reaction (PCR)-positive 8 days after disease onset in a Kaplan-Meier survival curve. The longest observed duration of viral shedding was 12 days. The average viral load was initially low, peaked on days 2-3 of disease and then declined. Viral decline results remained similar when all 15 (25%) oseltamivir-treated patients were excluded. Significant antibody titre changes were seen in all the 35 PCR verified cases with available paired sera and in 8 of the 58 patients with negative PCR tests on acute phase nasal samples. In conclusion, quantitative PCR testing indicated the presence of influenza virus for up to 12 days, which could have implications for disease transmission and infection control.

Aerosolization and recovery of viable murine norovirus in an experimental setup.

Noroviruses are the major cause for viral acute gastroenteritis in the world. Despite the existing infection prevention strategies in hospitals, the disease continues to spread and causes extensive and numerous outbreaks. Hence, there is a need to investigate the possibility of airborne transmission of norovirus. In this study, we developed an experimental setup for studies on the infectivity of aerosolized murine norovirus (MNV), a model for the human norovirus. Two aerosol generation principles were evaluated: bubble bursting, a common natural aerosolization mechanism, and nebulization, a common aerosolization technique in laboratory studies. The aerosolization setup was characterized by physical and viral dilution factors, generated aerosol particle size distributions, and the viral infectivity after aerosolization. We found a lower physical dilution factor when using the nebulization generator than with the bubble bursting generator. The viral dilution factor of the system was higher than the physical dilution; however, when comparing the physical and viral dilution factors, bubble bursting generation was more efficient. The infectivity per virus was similar using either generation principle, suggesting that the generation itself had a minor impact on MNV infectivity and that instead, the effect of drying in air could be a major reason for infectivity losses.

No evidence of intrauterine transmission of hepatitis A virus from a mother to a premature infant.

AIM: To determine whether or not an intrauterine transmission of hepatitis A virus (HAV) occurred from an infected mother to her premature infant delivered by caesarean section. METHODS: The mother and her child were tested for HAV by serology and reverse transcription PCR. RESULTS: An outbreak of HAV infection was seen among children and a 33-year-old day-care teacher, pregnant in third trimester, at a day-care centre in southern Sweden. Due to premature labour and diminished foetal movements a caesarean section was performed and a premature girl in gestational weeks 33 + 1 was born. During the 3-week postnatal hospitalization period the child presented no clinical symptoms of HAV infection and anti-HAV IgM antibodies remained undetectable at day 14 and 109 after birth. Furthermore HAV RNA remained undetectable by reverse transcription PCR in the child's blood at birth and in throat and faeces for the first 3 and 4 weeks of life respectively. HAV RNA in the mother's blood was detected at 6 days prior to and at 17 days after delivery. HAV RNA was undetectable in breast milk when tested on day 3 after delivery. CONCLUSION: There was no evidence of intrauterine transmission of hepatitis A virus from a viraemic mother to her premature child delivered at gestational week 33 + 1 by caesarean section.

Hydrogen peroxide vapour treatment inactivates norovirus but has limited effect on post-treatment viral RNA levels.

BACKGROUND: Hydrogen peroxide vapour is used as a room disinfectant. Its activity against murine norovirus, a surrogate viability marker for human norovirus, indicates that it is also active against human norovirus. AIM: The aim of this study is to assess how this effect on viability is reflected in measurements of RNA by quantitative PCR (qPCR). METHODS: Faeces suspensions of two human norovirus field strains, genogroup I and II and one cultured murine norovirus strain, (genogroup V) were dried on plastic plates, and underwent hydrogen peroxide vapour treatment or were mock treated. The influence of hydrogen peroxide on RNA was measured on genogroups I, II and V by qPCRs and for the cultivable murine norovirus also for viability by cell culture. Virucidal activity on murine norovirus was measured by endpoint titrations as the 50% tissue culture infectious dose, based both on cytopathic effect and on presence of replicating intracellular minus strand RNA. RESULTS: The mean impact on the human norovirus qPCRs was 0.4 log10. The murine norovirus qPCR changed by 1.7 log10 but by an alternative qPCR only by 0.4 log10. These minor changes contrasted the 4.5-5.0 log10 murine norovirus viability reduction after treatment measured by cytopathic effect or intracellular negative-strand RNA. CONCLUSION: Inactivation of murine norovirus viability by hydrogen peroxide vapour was not reflected in qPCR levels. This finding might be extrapolated to the related human norovirus genogroups. We further found that cellular minus strand murine norovirus PCR was an observer-independent marker to study reduction of murine norovirus viability.

Norovirus strains belonging to the GII.4 genotype dominate as a cause of nosocomial outbreaks of viral gastroenteritis in Sweden 1997--2005. Arrival of new variants is associated with large nation-wide epidemics.

BACKGROUND: In recent years an increase of the incidence of nosocomial outbreaks caused by noroviruses has been observed throughout Sweden, with high peaks noted in the winter seasons 2002/2003 and 2004/2005, respectively. OBJECTIVES: To phylogenetically characterize norovirus strains causing nosocomial outbreaks from 1997 to 2005 and estimate the impact of norovirus-like disease on the Swedish health care system during the peak season 2002/2003 when a new variant of norovirus occurred. STUDY DESIGN: Stool samples from 115 randomly selected nosocomial outbreaks occurring during 1997--2005 throughout Sweden were studied by RT-PCR and sequencing. In addition, to investigate the impact on the health-care system, a questionnaire was distributed to infection control units (n=90) serving all Swedish hospitals, nursing homes and other health-care institutions during the largest epidemic of nosocomial outbreaks. RESULTS: Sequencing of 279 nucleotides of the norovirus RNA polymerase gene in stools containing norovirus RNA showed that strains belonging to the GII.4 genotype dominated. Each of the two large epidemics was due to a new variant within this cluster. The questionnaire revealed that 30,000-35,000 episodes of nosocomial norovirus-like infections occurred in 80 of 82 major Swedish hospitals affected in 2002/2003. CONCLUSION: New norovirus variants within the cluster GGII.4 may have a major impact on the health-care system.

Prospective study of nosocomial transmission of hepatitis C in a Swedish gastroenterology unit .

A prospective study of incident hepatitis C in 515 gastroenterology patients was conducted by follow-up sampling at 3-6 months after admission to the gastroenterology unit to test for antibodies to hepatitis C virus and for hepatitis C virus RNA. Universal precautions were implemented, and the use of multidose vials had been banned in this unit. Despite 5,964 exposure-days for several risk factors associated with nosocomial hepatitis C virus transmission, no incident case of hepatitis C occurred.

Around-the-clock, rapid diagnosis of influenza by means of membrane chromatography antigen testing confirmed by polymerase chain reaction.

One rapid membrane chromatography test and 2 immunofluorescence tests were compared with polymerase chain reaction as tools for the diagnosis of influenza in 277 patients treated in an emergency department. The sensitivity on days 1-3 of symptoms was 71% for the rapid membrane chromatography test, 70% for the first immunofluorescence test, and 79% for the second immunofluorescence test. Rapid tests are useful for round-the-clock identification of influenza, with follow-up polymerase chain reaction used for confirmation.

Prevalence of hepatitis C in Swedish diabetics is low and comparable to that in health care workers.

OBJECTIVES: An association between hepatitis C virus (HCV) infection and diabetes has been reported, in particular from countries with a high prevalence of HCV. To assess if this association could be found in a region with low prevalence of HCV (0.33%), we determined the prevalence of anti-HCV in a large cohort of patients with diabetes. METHODS: The prevalence of anti-HCV was determined with an enzyme-linked immunosorbent assay in 874 patients with diabetes representing 72.5% of a total research cohort of 1205 patients who were invited to participate. The results were confirmed with immunoblot. Samples from confirmed patients were tested for HCV RNA and genotyped. RESULTS: In 499 patients with type 1 diabetes and 375 patients with type 2 diabetes six patients were anti-HCV positive (four with type 1 diabetes and two with type 2 diabetes corresponding to a prevalence of 0.80 and 0.53%, respectively, in accordance with the prevalence among health care workers in Sweden; 0.68%). Liver biopsies in three of the patients showed only mild inflammation without fibrosis and in two of the other three the albumin and/or PT-INR level was normal contradicting any substantial impairment of the liver function. CONCLUSIONS: The low anti-HCV prevalence that we found contradicts an etiologic role of HCV in the development of diabetes in Sweden. The risk of being infected with HCV when attending the health care system seems to be rather small in a low-prevalence area.

Enhanced and resumed GB virus C replication in HIV-1-infected individuals receiving HAART.

In patients co-infected with HIV-1 and GB virus C (GBV-C), the disappearance of GBV-C RNA has been associated with accelerated disease progression. We studied longitudinal GBV-C viral titres in 28 HIV-1/GVB-C co-infected individuals receiving HAART. During HAART, median GBV-C RNA titres increased from 95 to 6000 copies/ml (P < 0.001). In patients interrupting HAART, GBV-C-RNA titres decreased as HIV replication resumed. These findings further support the theory that GBV-C replication could depend on the dynamics of HIV progression.