Somatic coliphages are conservative indicators of SARS-CoV-2 inactivation during heat and alkaline pH treatments.

High concentrations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome have been described in wastewater and sewage sludge. It raises the question of the security of land sludge disposal practices during a pandemic. This study aimed to compare SARS-CoV-2's resistance to the main inactivating factors in sludge treatments, pH and heat, to that of native wastewater somatic coliphages. The latest can be easily used as an indicator of treatment efficiency in the field. The effects of heat treatment and pH on the survival of SARS-CoV-2 and somatic coliphages were investigated in simple media. The T90 value (time required for a 90% reduction in the virus or a 1 × log10 decline) at 50 °C was about 4 min for infectious SARS-CoV-2, and around 133 min for infectious somatic coliphages, with no decrease in SARS-CoV-2 genome. For infectious SARS-CoV-2, a slight decrease (<1 log10 unit) was observed at pH 9 or 10 for 10 min; the decrease was over 5 log10 units at pH 11. However, both SARS-CoV-2 genome and infectious somatic coliphages decreased by less than 1 log10 unit at pH 12. All thermal or pH-based treatments that can remove or significantly reduce infectious somatic coliphages (>4 log10) can be considered efficient treatments for infectious SARS-CoV-2. We concluded that somatic coliphages can be considered highly conservative and easy to use indicators of the inactivation of SARS-CoV-2 during treatments based on heat and alkaline pH.

Molecular features of Hepatitis E Virus circulation in environmental and human samples.

BACKGROUND AND OBJECTIVES: Hepatitis E virus (HEV) is emerging but its circulation between humans and the environment remains misunderstood. HEV ORF2 gene encodes the capsid playing a key role in viral interactions with surfaces, ORF3 products are involved in the viral cycle. Our aim was to study the molecular characteristics of ORF2 and ORF3 which could favor HEV fitness in patients and the environment. STUDY DESIGN: Samples from 69 patients with hepatitis (blood/stools), 20 urban wastewaters, 20 effluents of a pig slaughterhouse, 22 farm pigs (stools), 20 wild boars (liver/stools) were collected in North-Eastern France. HEV strains were analyzed by direct sequencing within the ORF2 M region, of ORF2/ORF3, for phylogeny and physicochemical prediction and for ORF2 by ultra-deep sequencing. RESULTS: The results showed frequent HEV-positive samples: 9.1% of the patient bloods, 23.1% of their stools; 25.0% of wastewaters, 75.0% for the slaughterhouse, 10.0% of the boar livers, 5.3% of their stools. The strains were classified as HEV genotype 3. In ORF2, HEV highlighted one homogeneous major viral variant within quasispecies and a decrease in predicted antigenicity for two minor mutations (D442G, V402A). A cysteine signature at position 81 in ORF3 was observed in the boars. CONCLUSIONS: HEV RNA genotype 3 was detected in patients and in animals, in a slaughterhouse effluent and in wastewater. Moreover, the low variability of amino acids in the ORF2 M region and molecular features in ORF2 and ORF3 suggested that HEV strains could be advantageous for key properties.

Herpes simplex virus type 1 hepatitis due to primary infection in a pancreas-kidney transplant recipient.

Herpes simplex Virus (HSV) hepatitis is a rare complication of HSV-1 primary infection, with a delayed diagnosis, affecting mainly immunocompromised patients. We describe a case of HSV-1 hepatitis after primary infection occurring in the postoperative days after a pancreas-kidney transplantation. The patient presented with an unusual evolution of a persistent severe hepatitis associated with a persistent viremia (Quantitative Polymerase Chain Reaction) despite an adequate intravenous (iv) antiviral treatment. Abdominal computed tomography scan showed a miliary hepatitis. The diagnosis of HSV-1 hepatitis was confirmed by immuno-chemistry on liver biopsy. The donor was negative for anti-HSV antibodies, excluding contamination by the graft. This case report emphasizes a rather seldom risk of care-associated viral infections, predominantly in immunocompromised patients.

Characterization of hepatitis B virus surface antigen variability and impact on HBs antigen clearance under nucleos(t)ide analogue therapy.

For hepatitis B virus (HBV)-related chronic infection under treatment by nucleos(t)ide analogues (NUCs), HBsAg clearance is the ultimate therapeutic goal but very infrequent. We investigated how HBV envelope protein variability could lead to differential HBsAg clearance on NUCs. For 12 HBV genotype D patients receiving NUCs, six resolvers (HBsAg clearance) were compared to six matched nonresolvers (HBsAg persistence). PreS/S amino acid (aa) sequences were analysed with bioinformatics to predict HBV envelope antigenicity and aa covariance. To enrich our analyses on very rare resolvers, these were compared with other HBV genotype D strains in three characterized clinical cohorts including common chronically infected patients. The sT125M+sP127T combination was observed in four nonresolvers of six, corroborated by aa covariance analysis, associated with a lower predicted antigenicity than sT125T+sP127P. Concordant features within this HBV key functional domain, at positions 125 and 127, were reported from two of the three comparative cohorts. In our hands, a lower ELISA reactivity of HBV-vaccinated mice sera was observed against the sT125M mutant. In the S gene, 56 aa changes in minor variants were detected in non-resolvers, mainly in the major hydrophilic region, vs 28 aa changes in resolvers. Molecular features in patients showing HBsAg persistence on NUCs argue in favour of a different aa pattern in the HBV S gene compared to those showing HBsAg clearance. In nonresolvers, a decrease in HBs 'a' determinant antigenicity and more frequent mutations in the S gene suggest a role for the HBV envelope characteristics in HBsAg persistence.

Real-life rilpivirine resistance and potential emergence of an E138A-positive HIV strain in north-eastern France.

OBJECTIVES: To assess the prevalence of resistance to rilpivirine and mutations at position 138 in reverse transcriptase and to identify associated epidemiological and biological characteristics. METHODS: This retrospective study included 238 patients with available HIV-1 nucleotide sequences analysed at the Laboratory of Virology at the University Hospital of Nancy between January 2011 and June 2013. Resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) was evaluated according to the ANRS algorithm (version 23) and correlated with clinico-epidemiological and therapeutic data. The virus strains were analysed by evaluating the distance and distribution of the phylogenetic tree (MEGAv5). RESULTS: Among previously treated patients (111/238, 46.6%), 68/111 (61.3%) had received NNRTIs; all were rilpivirine-naive. The prevalence of rilpivirine resistance in the whole cohort was 12.6% (30/238), and was 10.2% (13/127) and 15.3% (17/111) in naive and pre-treated patients, respectively. The E138A mutation was the most frequent mutation associated with resistance to rilpivirine (P < 0.0001). The prevalence of the E138A mutation tended to increase over time, from 3.6% (2/55) during the first half of 2011 to 9.3% (4/43) during the first half of 2013 (P = 0.0614). Seven viral strains from seven naive male patients positive for the E138A mutation appeared in the same cluster. CONCLUSIONS: In our cohort of patients, we observed significantly increased resistance to rilpivirine, mostly because of the E138A mutation, probably due to an E138A strain circulating in newly diagnosed men who have sex with men. Taken together, our results emphasize the need to investigate the prevalence of rilpivirine resistance-associated mutations in the coming years both in France and abroad.

[Six cases of spring DRESS]. / Six cas de DRESS printaniers.

BACKGROUND: An association between herpes virus reactivations and Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is accepted. We report six cases of DRESS with viral reactivation occurring within a single 1-month period. We attempted to find a common factor for these six cases and carried out clinical and virological examinations. Before and after this "epidemic", the mean number of cases of DRESS seen at the same centre was one per quarter, making the occurrence of six cases within a single month all the more remarkable and prompting us to seek an explanation. PATIENTS AND METHODS: All six patients had taken a partly causative medication from different drug classes three to six weeks prior to the start of symptoms and herpes virus was detected in the blood of all of these subjects at the time of DRESS onset (four reactivations and two primary infections), and one patient subsequently displayed herpetic meningoencephalitis 95 days after the initial episode, associated with recurrence of DRESS. DISCUSSION: There was no common denominator among these six DRESS patients in terms of either drug class or reactivation of a particular type of herpes virus, which raises the possibility of a single unidentified environmental agent. DRESS does not appear fully explainable in terms of a cellular response to drug antigens but seems rather to result from complex interactions between the drug-induced immune response, viral reactivation and antiviral immune response. Several investigators have reported sequential reactivation of herpes viruses in DRESS. A viral epidemic could thus cause a "DRESS epidemic" in patients on medication. CONCLUSION: These cases point to the possible existence of a shared initial environmental factor (infectious or not) that favours reactivation of herpes viruses and induces DRESS in patients on medication. Before and after this "DRESS epidemic", about one patient each quarter was admitted to hospital for DRESS.

Diagnostic value of quantitative PCR for adenovirus detection in stool samples as compared with antigen detection and cell culture in haematopoietic stem cell transplant recipients.

Adenovirus (AdV) infections constitute a significant cause of morbidity and mortality during haematopoietic stem cell transplantation. Recent guidelines recommend repeated screening for AdV in whole blood (WB), with quantitative PCR (qPCR) as the reference standard. Despite pre-emptive antiviral treatment based on qPCR in WB, the mortality rate after disseminated AdV infection remains very high. The aim of our study was to advance early screening for AdV, using a standardized method, so as to enable the earlier initiation of antiviral treatment or adoptive immunotherapy. The diagnostic value of AdV DNA quantification in stool samples was investigated retrospectively and compared with antigen detection and cell culture in 21 patients with AdV infection, from 182 patients followed in the Transplant Unit of Nancy University Hospital Centre, including 18 patients with systemic infection. In 16/18 patients with positive AdV viraemia, AdV DNA was present in stool samples earlier than in WB (median, 42 days; range, 3-199 days), whereas both antigen detection and cell culture were still negative for 11/18 patients with systemic AdV infection. The course of AdV viral loads in stool samples was predictive of adenoviraemia (sensitivity, 89%). Very late and lethal AdV infections were observed in cord blood transplant recipients, and would have been detected much earlier with the use of qPCR on stool samples. This study confirmed that quantification of AdV in stool samples by qPCR is beneficial for the management of transplant recipients, with or without antigen detection.

Occult hepatitis B infection in patients infected with HIV: report of two cases of hepatitis B reactivation and prevalence in a hospital cohort.

Patients co-infected with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are particularly at risk of hepatitis B reactivation. Two cases of patients infected with HIV with isolated anti-HBc antibodies who had experienced an HBV reactivation are described. In the two cases HBV reactivation occurred after withdrawal of anti-retroviral treatment with anti-HBV activity from the patients' highly active antiretroviral therapy (HAART), in accordance with HIV genotypic resistance profiles. Consequently, plasma samples from 383 patients infected with HIV were tested to assess the prevalence of occult HBV infection in the Infectious Diseases Department Unit of Nancy Hospital by investigating serological patterns and HBV replication. Forty-five percent (172/383) of patients had had previous contact with HBV. Isolated anti-HBc antibodies were observed in 48 patients (48/383, 12%) and, among these, 2 were HBV-DNA positive. Since 75% (288/383) of the patients were treated with HAART, including at least one drug active against HBV, occult HBV infection was perhaps unrecognized. In cases of HIV infection, all patients should be screened for HBV infection and the knowledge of HBV status as well as the monitoring of HBV viral load are essential in preventing HBV reactivation. Consideration should be given to the continuation of drugs with anti-HBV activity in co-infected patients receiving HAART, as cessation of therapy is associated with a risk of HBV reactivation. At least, close monitoring of the HBV viral load is warranted in such situations.

[Neutropenia and/or thrombocytopenia due to acute parvovirus B19 infection]. / Neutropénie et/ou thrombopénie associée(s) à une infection aiguë par le parvovirus B19.

Erythema infectiosum (fifth disease) is the most common clinical presentation of acute parvovirus B19 infection in infancy. In healthy adults, most cases of infection are asymptomatic or accompanied by a flu-like syndrome like headaches and myalgia. Haematological manifestations are dominated by transient aplasia of erythroid progenitor cells which remains asymptomatic in most of non immunocompromised patients. Patients with sickle cell disease, thalassemia or other disorders associated with shortened red blood cell survival are at particular risk for marked anemia or red blood cell aplasia. In immunosuppressed patients, anemia may be chronic because of persistent viral load. Neutropenia, lymphopenia or thrombocytopenia have also been reported in acute parvovirus B19 infection. Mechanisms of these cytopenias are not yet elucidated. We present two patients with thrombopenia and/or neutropenia but without anemia due to acute parvovirus B19 infection.

Effective ribavirin concentration in mice brain using cyclodextrin as a drug carrier: evaluation in a measles encephalitis model.

Ribavirin (RBV) is a water-soluble synthetic nucleoside with broad spectrum antiviral properties, but it is ineffective against major viral encephalitis because of a failure to cross the blood-brain barrier (BBB). The antiviral activity of the complex ribavirin/alpha-cyclodextrin was previously demonstrated to be stronger than free ribavirin, in an in vivo model of measles virus (MV) encephalitis in mice. The role of cyclodextrin (CD) on ribavirin uptake into the brain needs to be defined. Ribavirin specific extraction from brain tissue was developed, based on a solid phase extraction. It was quantified by high performance liquid chromatography at different time points after intraperitoneal injection of single or multiple doses of free ribavirin or of the complex ribavirin/alpha-cyclodextrin. Whatever the tested dose (40 or 100mg/kg), the amount of ribavirin in the brain was significantly higher (p<0.001) when the drug was injected as a complex with alpha-cyclodextrin, in healthy or measles virus-infected mice.

[What future for ribavirin beyond hepatitis C therapy?] / Quel avenir pour la ribavirine en dehors de l'hépatite C ?

Most of emerging and re-emerging diseases are due to RNA viruses and available drugs are insufficient. Currently the ribavirin is only licensed for the treatment of chronic hepatitis C infection, whereas this guanosin analogue has a broad-spectrum in vitro activity against many DNA and RNA viruses. It was consequently used as a last resort, in emergency state like avian influenza or in front of new viruses (SARS). The strategies for development of new antiviral drugs are usually based on virus structure and properties. In regard to recent development of chemical vector designed for improving drug bioavailability, use of former drug, like ribavirin, could be reconsidered. For example, complexation of ribavirin with cyclodextrins, cyclic oligosaccharide vectors, can improve its bioavailability in central nervous system and improve encephalitis treatment.

In vivo antiviral activity of ribavirin/alpha-cyclodextrin complex: evaluation on experimental measles virus encephalitis in mice.

Intracranial injection of the rodent adapted CAM/RB strain of measles virus (MV) induces encephalitis in CBA/ca mice. It has already been shown that cyclodextrins can be used as carriers to increase the antiviral activity of ribavirin (RBV) against MV in cellular model. In this study, the antiviral activity of a RBV/alpha-cyclodextrin complex has been evaluated in vivo using the above model. CBA/ca mice were treated by intraperitoneal injection of free ribavirin (40 mg/kg) or a RBV/alpha-cyclodextrin complex (molar ratio 1:3). After 21 days, intracerebral injection of CAM/RB resulted in 100% mortality in the mock group. In contrast, mortality rates of 80% and 40%, respectively, were observed in RBV and RBV/alpha-CD-treated mice (p<0.05 and p=0.06 for distilled water and RBV, respectively). The viral load of MV in the mouse brain was monitored daily by real-time PCR until day 6 after infection, to compare virus production in treated and non-treated mice. This data shows that RBV complexation with alpha-cyclodextrin can increase the antiviral activity of ribavirin in a measles virus encephalitis model in mice.

Evaluation by Q-RTPCR of the efficacy of ribavirin complexed with beta-cyclodextrin against measles virus in a mouse encephalitis model.

The objective of this work was to study the antiviral activity of ribavirin on measles encephalitis infection when using cyclodextrins as carriers. The use of cyclic oligosaccharides can promote the activity of many drugs and the benefit of the association of ribavirin with beta-cyclodextrin has already been demonstrated in vitro. Intracranial inoculation of the rodent adapted neurovirulent CAM/RB strain of measles virus induces encephalitis in CBA/ca mice. The antiviral activity of the complex ribavirin/beta-cyclodextrin at molar ratio 1:1 has been evaluated in vivo in the above encephalitis model. CBA/ca mice were treated with daily intraperitoneal injection of ribavirin (40 mg/kg) with or without beta-cyclodextrin. The viral load in the brain of mice was quantified by real-time Reverse transcription-Polymerase chain reaction. Treatment of mice by the complex ribavirin/beta-cyclodextrin (1:1) by intraperitoneal route decreases the viral load in the brain of 1.1 and 0.7 log(10) Eq copies x mL(-1) compared to distillated water and ribavirin treatment, respectively. At the same time, free ribavirin injection shows a negligible difference compared to treatment by distillated water.