ABSTRACT
BACKGROUND: Antiviral resistance in Norwegian influenza viruses is rare. Only one A(H1N1)pdm09 virus from May 2015 had been found resistant to oseltamivir since the introduction of these viruses in 2009. OBJECTIVES: Surveillance of antiviral resistance is part of the Norwegian surveillance system, to rapidly detect the development of antiviral-resistant viruses and spread in the community. We describe the spread of oseltamivir-resistant A(H1N1)pdm09 viruses in Norway in the 2016-17 season, found as part of the routine surveillance. METHODS: Influenza H1N1 viruses were analysed for antiviral resistance by pyrosequencing, neuraminidase susceptibility assay and by Sanger sequencing of the HA and NA genes. RESULTS: During the 2015-16 influenza season, 3% of all A(H1N1)pdm09 viruses screened for resistance in Norway were resistant to oseltamivir, possessing the H275Y substitution in the neuraminidase protein. In comparison, the overall frequency in Europe was 0.87%. Out of these, 37% (n = 10) were reported from Norway. Most cases in Norway were not related to antiviral treatment, and the cases were from several different locations of southern Norway. Genetic analysis revealed that resistant virus emerged independently on several occasions and that there was some spread of oseltamivir-resistant influenza A(H1N1)6B.1 viruses in the community, characterised by a N370S substitution in the haemagglutinin and T48I in the neuraminidase. CONCLUSIONS: Our findings emphasise the importance of antiviral resistance surveillance in the community, not only in immunocompromised patients or other patients undergoing antiviral treatment.
Subject(s)
Antiviral Agents/pharmacology , Drug Resistance, Viral/genetics , Influenza A Virus, H1N1 Subtype/drug effects , Influenza, Human/epidemiology , Oseltamivir/pharmacology , Adult , Aged , Child, Preschool , Female , Humans , Incidence , Influenza A Virus, H1N1 Subtype/genetics , Male , Middle Aged , Norway , Point Mutation , Sequence Analysis, DNA , Viral ProteinsABSTRACT
BACKGROUND: Liver transplantation regularly requires transfusion of red blood cells (RBCs), plasma, and platelets. Compared to fresh frozen plasma (FFP) from single blood donors, solvent/detergent-treated plasma (SD-plasma) pooled from several hundred blood donors has advantages with respect to pathogen reduction, standardized content of plasma proteins, and significantly reduced risk of transfusion related lung injury and allergic/immunologic adverse reactions. However, SD-plasma has been suspected to increase the incidence of hyperfibrinolysis and thromboembolic events. STUDY DESIGN AND METHODS: We investigated the transfusion practices, hyperfibrinolysis parameters, and thrombosis outcomes in 195 consecutive adult primary liver transplants in our center using SD-plasma (Octaplas) as the exclusive source of plasma. RESULTS: Perioperatively, median (interquartile range) 4 (1 to 9) RBC-units, 10 (4 to 18) plasma-bags, and 0 (0 to 2) platelet-units were transfused. Hyperfibrinolysis defined as LY30 ≤ 7.5% was detected in 12/138 thrombelastography-monitored patients (9%). These patients received significantly more RBCs, plasma, and platelets than did patients without hyperfibrinolysis. Thrombotic graft complications were observed in three patients (2%). Pulmonary embolism was not observed in any patient. CONCLUSION: SD-plasma is a safe plasma product for liver transplant recipients, and the incidences of hyperfibrinolysis and thromboembolic events are not significantly different from those seen in centers using FFP.
