The First Isolation and Whole Genome Sequencing of Murray Valley Encephalitis Virus from Cerebrospinal Fluid of a Patient with Encephalitis.

Murray Valley Encephalitis virus (MVEV) is a mosquito-borne Flavivirus. Clinical presentation is rare but severe, with a case fatality rate of 15⁻30%. Here we report a case of MVEV from the cerebrospinal fluid (CSF) of a patient in the Northern Territory in Australia. Initial diagnosis was performed using both MVEV-specific real-time, and Pan-Flavivirus conventional, Polymerase Chain Reaction (PCR), with confirmation by Sanger sequencing. Subsequent isolation, the first from CSF, was conducted in Vero cells and the observed cytopathic effect was confirmed by increasing viral titre in the real-time PCR. Isolation allowed for full genome sequencing using the Scriptseq V2 RNASeq library preparation kit. A consensus genome for VIDRL-MVE was generated and phylogenetic analysis identified it as Genotype 2. This is the first reported isolation, and full genome sequencing of MVEV from CSF. It is also the first time Genotype 2 has been identified in humans. As such, this case has significant implications for public health surveillance, epidemiology, and the understanding of MVEV evolution.

Prevalence of transmitted HIV drug resistance since the availability of highly active antiretroviral therapy.

We investigated the prevalence of HIV-1-associated transmitted drug resistance (TDR) in Victoria from the time of first availability of highly active antiretroviral therapy. Drug resistance genotyping was performed on virus present in blood samples collected from individuals with serologically confirmed primary infection, between 1996 and 2007. The significance of any mutations detected was interpreted according to a standardised list of drug resistance mutations. The main outcomes measured were the prevalence by year of TDR to any antiretroviral drug class, the numbers of infected individuals with TDR involving multiple drug classes, and the resistance mutations implicated in all cases. There was an average annual prevalence of TDR of 16%, predominantly associated with nucleoside and non-nucleoside reverse transcriptase (RT) inhibitors and most commonly occurring at codons 41, 103 and 215 in the RT. The prevalence of thymidine-associated mutations remained high throughout the period of study. While mutations known to cause resistance to protease inhibitors were uncommon, they were present in several individuals infected with virus resistant to multiple drug classes. The prevalence of TDR in Victoria is similar to geographical locations outside Australia where HIV-specific drug treatment is widely available. Primary infection with drug resistant HIV is a future treatment issue for the individual patient and for the wider population at risk of infection. At this time TDR shows no sign of waning and our data support recent treatment guidelines recommending baseline testing for TDR before therapy is initiated.

Cleaning and sterilization protocol for reused cardiac electrophysiology catheters inactivates hepatitis and coxsackie viruses.

OBJECTIVE: To assess the efficacy of a standard cleaning and sterilization protocol employed during reuse of cardiac electrophysiology catheters on the infectivity of duck hepatitis B virus (DHBV; a surrogate for human hepatitis B virus), bovine viral diarrhea virus (BVDV; a surrogate for human hepatitis C virus), and human coxsackie type B3 virus (CB3). SETTING: Public health virology laboratory. METHODS: Studies were performed on the distal, electrode-containing segments of 120 electrophysiology catheters previously used in up to 10 clinical procedures. Catheter segments were immersed for 1 hour in blood infected with high titers of DHBV, BVDV, or CB3. After air drying for 2 hours, subgroups of 8 catheters were subjected to no treatment, washing in general-purpose detergent, washing in enzyme cleaner, sterilization in ethylene oxide, or the full protocol of sequential detergent-enzyme cleaner-ethylene oxide exposure. Presence of residual virus was assessed by nucleic acid detection and infectivity studies. RESULTS: DHBV nucleic acid was detected on catheters after individual steps and the full protocol, whereas BVDV and CB3 nucleic acids were detected after individual steps but not the full protocol. These findings were associated with the presence of infectious DHBV and CB3, but not BVDV, on catheters after washing in detergent or enzyme cleaner. However, ethylene oxide alone or the full protocol reduced infectivity of all three viruses to undetectable levels. CONCLUSION: These experimental studies provide strong evidence that appropriate cleaning and sterilization of reused electrophysiology catheters inactivates blood-borne viruses such as hepatitis B and C and coxsackie type B3.

A decontamination and sterilization protocol employed during reuse of cardiac electrophysiology catheters inactivates human immunodeficiency virus.

OBJECTIVE: To assess the effect of a standard decontamination and sterilization protocol employed during reuse of cardiac electrophysiology (EP) catheters on human immunodeficiency virus (HIV). SETTING: Public health viral research laboratory. METHODS: Studies were performed on distal, electrode-containing segments of 40 EP catheters previously used in up to 10 clinical EP procedures. EP catheter segments were immersed for 1 hour in blood contaminated with a high titer of HIV. After air drying for 2 hours, subgroups of 8 EP catheters were subjected to either (1) no treatment, (2) washing in general purpose detergent, (3) washing in enzyme cleaner, (4) sterilization in ethylene oxide, or (5) the full protocol of sequential detergent-enzyme cleaner-ethylene oxide exposure. HIV infectivity after treatment was determined by measuring HIV RNA and, in cell culture studies, assessing HIV-induced cytopathic effects (CPEs) and supernatant HIV-specific p24 antigen content RESULTS: With no treatment, all catheters had high HIV RNA levels associated with CPEs and high p24 antigen levels. After washing in detergent, 5 of 8 catheters had HIV RNA detected, but without CPEs or p24 antigen. HIV RNA was detected in all catheters after washing in enzyme cleaner, with CPEs and a high p24 antigen level in 1 of 8 catheters. HIV RNA, CPEs, and p24 antigen were absent after ethylene oxide. After the full protocol, HIV RNA levels were undetectable (n = 7) or low (n = 1), without evidence of CPEs or p24 antigen. CONCLUSION: Appropriate decontamination and sterilization of EP catheters during reuse is highly effective in inactivating HIV.