These results indicate that the clinical and serum biochemical response to alpha-interferon in chronic hepatitis C is associated with a loss of detectable HCV genome from serum.

West Nile virus (WNV) has become an increasing issue in the transfusion setting since 2002, when it was firstly shown in the USA that it can be transmitted through blood transfusion. Since then, several precautionary measures have been introduced in Europe in order to reduce the possible risk of transmission via transfusion/solid organ transplantation. In addition, the epidemiological surveillance has been tightened and the network for communication of human WNV cases strengthened. This review will focus on WNV circulation and the safety of blood in Europe.

The recently introduced antibody test for hepatitis C virus infection has already proved to be valuable in many situations such as screening blood donors and diagnosing chronically infected patients, but this antibody assay has certain limitations. Hepatitis C virus itself is usually present in clinical specimens at very low titers; therefore a useful assay for the virus must have very high sensitivity. We have developed a simple, highly sensitive assay for hepatitis C virus RNA based on the polymerase chain reaction. In this test RNA extracted from hepatitis C virus-infected serum or plasma is used as the template for double polymerase chain reaction with nested primers. Sensitivity studies demonstrate that this assay is able to detect hepatitis C virus at or beyond the sensitivity level of chimpanzee infectivity. Preliminary studies in chronic non-A, non-B hepatitis showed that 16 of 36 patients positive for antibody to hepatitis C virus and 2 of 4 patients negative for antibody to hepatitis C virus were positive in the polymerase chain reaction test. By retesting the polymerase chain reaction-negative patients with several sets of polymerase chain reaction primers, we found hepatitis C virus RNA in 35 of the 40 patients including all 4 seronegative patients. Normal human plasma and plasma from patients with hepatitis B infection did not react in this test. This assay has proved to be valuable for determining the presence of hepatitis C virus RNA in various samples. Furthermore, it offers the possibility of diagnosis of hepatitis C virus infection in patients who do not react in the presently available antibody tests.

No abstract

Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the 'WHO global polio eradication program', is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.