Five tungsten carbide nanoparticle preparations (denoted WC1-WC5) were investigated for broad spectrum virucidal activity against four recommended model viruses. These are modified vaccinia virus Ankara (MVA), human adenovirus type 5 (HAdV-5), poliovirus type 1 (PV-1) and murine norovirus (MNV). All virucidal tests were performed two to five times using the quantitative suspension test, which is a highly standardized test method to evaluate the virucidal efficacy of disinfectants in accordance with the European norm EN 14476+A1 and the German DVV/RKI guidelines. Quantitative detection of viruses was conducted by endpoint titration and quantitative real-time PCR. Results showed that three of the five tested compounds (WC1-WC3) were able to reduce the infectivity of all model viruses by at least four log10 of tissue culture infective dose 50% per ml after 15 min, whereas the other two compounds exhibited only limited efficacy (WC4) or showed cytotoxicity (WC5). Virucidal activity of nanoparticles increased with incubation time and a dose-effect curve showed dependence of virucidal activity with particle concentration. Whereas WC1-WC4 showed little cytotoxicity, WC5 which was doped with copper exhibited a significant cytotoxic effect. These findings propose tungsten carbide nanoparticles to be very promising in terms of new disinfection techniques. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study investigates the virucidal activity of tungsten carbide nanoparticles using the quantitative suspension test in accordance with the European norm EN 14476+A1 and the German DVV/RKI guidelines. Due to highly standardized assay conditions, results of this test are considered very reliable for evaluation of the virucidal activity of disinfectants. Broad-spectrum activity and high efficacy of three different tungsten carbide nanoparticles preparations is concluded.

In 1988, the World Health Assembly of the World Health Organization (WHO) resolved to eradicate polio worldwide. Among the three wild poliovirus (WPV) types (type 1, type 2, and type 3), WPV type 2 (WPV2) has been eliminated in the wild since 1999, and WPV type 3 (WPV3) has not been reported since 2012. In 2015, only Afghanistan and Pakistan have reported WPV transmission. On May 25, 2015, all WHO Member States endorsed World Health Assembly resolution 68.3 on full implementation of the Polio Eradication and Endgame Strategic Plan 2013-2018 (the Endgame Plan), and with it, the third Global Action Plan to minimize poliovirus facility-associated risk (GAPIII). All WHO Member States have committed to implementing appropriate containment of WPV2 in essential laboratory and vaccine production facilities* by the end of 2015 and of type 2 oral poliovirus vaccine (OPV2) within 3 months of global withdrawal of OPV2, which is planned for April 2016. This report summarizes critical steps for essential laboratory and vaccine production facilities that intend to retain materials confirmed to contain or potentially containing type-specific WPV, vaccine-derived poliovirus (VDPV), or OPV/Sabin viruses, and steps for nonessential facilities† that process specimens that contain or might contain polioviruses. National authorities will need to certify that the essential facilities they host meet the containment requirements described in GAPIII. After certification of WPV eradication, the use of all OPV will cease; final containment of all polioviruses after polio eradication and OPV cessation will minimize the risk for reintroduction of poliovirus into a polio-free world.

OBJECTIVE: To develop a rapid detection method of enteroviruses and Hepatitis A virus (HAV).
METHODS: A one-step, single-tube consensus primers multiplex RT-PCR was developed to simultaneously detect Poliovirus, Coxsackie virus, Echovirus and HAV. A general upstream primer and a HAV primer and four different sets of primers (5 primers) specific for Poliovirus, Coxsacki evirus, Echovirus and HAV cDNA were mixed in the PCR mixture to reverse transcript and amplify the target DNA. Four distinct amplified DNA segments representing Poliovirus, Coxsackie virus, Echovirus and HAV were identified by gel electrophoresis as 589-,671-, 1084-, and 1128bp sequences, respectively. Semi-nested PCR was used to confirm the amplified products for each enterovirus and HAV.
RESULTS: All four kinds of viral genome RNA were detected, and producing four bands which could be differentiated by the band size on the gel. To confirm the specificity of the multiplex PCR products, semi-nested PCR was performed. For all the four strains tested gave positive results. The detection sensitivity of multiplex PCR was similar to that of monoplex RT-PCR which was 24 PFU for Poliovrus,21 PFU for Coxsackie virus,60 PFU for Echovirus and 105 TCID(50) for HAV. The minimum amount of enteric viral RNA detected by semi-nested PCR was equivalent to 2.4 PFU for Poliovrus, 2.1 PFU for Coxsackie virus, 6.0 PFU for Echovirus and 10.5 TCID(50) for HAV.
CONCLUSIONS: The consensus primers multiplex RT-PCR has more advantages over monoplex RT-PCR for enteric viruses detection, namely, the rapid turnaround time and cost effectiveness.

The aim of this study was to investigate the late effects of ABMT on the immune system with regard to protective humoral immunity against common antigens and responses to recall antigens (vaccines). The vaccines were given according to EBMT guidelines from 1995. The protocol included 35 patients with malignant lymphoma in CR 4-10 years after ABMT, and 35 controls. The results show that prior to ABMT the proportion of patients with protective immunity against poliomyelitis, tetanus and diphtheria was similar to that of controls. At study entry 4-10 years after ABMT, the proportion of patients with protective immunity against poliomyelitis and diphtheria was reduced, while all patients maintained protection against tetanus. A significant decrease in geometric mean antibody concentrations or titres was observed against all three antigens during this period. Serum levels of antibodies against different pneumococcal serotypes were lower in the patients than in the controls prior to vaccination. The responses to pneumococcal vaccination, which is considered to be a T cell-independent vaccine, were studied. Unlike controls, a minority of patients achieved protective levels of antibodies after a single vaccination. Despite persistent levels of protective antibodies in many patients post ABMT, secondary booster responses after one vaccination with T cell-dependent vaccines (tetanus, diphtheria and polio) were absent. In conclusion, this study shows that post ABMT, a full re-vaccination program was necessary to mount responses comparable to those observed after a single vaccination in controls.

Peroxygenic acid, under the brand name Virkon, has unleashed great debate following contradictory reports of its efficacy and spectrum of activity. The aim of this study was to test the biocidal activity of the compound against 10 different micro-organisms, following standard in-vitro test procedures. Bactericidal, fungicidal and sporicidal activities were determined using quantitative suspension and germ carrier tests and virucidal activity was assessed using a simple dilution suspension test, following the Association Française de Normalisation (AFNOR) guidelines. One percent Virkon demonstrated bactericidal activity against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Enterococcus hirae and Mycobacterium smegmatis in the suspension test and against P. aeruginosa, E. coli, S. aureus and E. hirae in the carrier test. One percent Virkon showed virucidal activity against poliovirus in the suspension test. However, this concentration did not comply with sporicidal and fungicidal activity guidelines. In conclusion, 1% Virkon is effective only against vegetative bacteria, yeasts and viruses, and should therefore be considered a low-level disinfectant.

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