How large is the zoonotic pool – all the animal viruses that could one day infect humans? Assuming that there are 50,000 vertebrates on earth, each with 20 viruses, the number is one million – probably a vast underestimate. Determining just how many viruses exist in a variety of animal species is technically feasible, limited …
The need to re-formulate the influenza virus vaccine in response to viral antigenic drift and shift makes for complex logistics of vaccine production and administration. Surveillance programs must be conducted each year to identify strains that are likely to predominate and cause disease. Wouldn€™t it be simpler if a single vaccine could be developed that …
All known virus particles can be placed into one of two general categories: enveloped or non-enveloped. Viruses that fall into the former category are characterized by a lipid membrane derived from the host cell, and one or more nuclecapsid proteins that interact with the viral genome. A virus that infects an archaeal host may constitute …
The illustration at left depicts a virion – the infectious particle that is designed for transmission of the nucleic acid genome among hosts or host cells. A virion is not the same as a virus. I define virus as a distinct biological entity with five different characteristics. Others believe that the virus is actually the …
The influenza virus neuraminidase (NA) protein is required for virus release from the cell, a property exploited by the antiviral drugs oseltamivir (Tamiflu) and zanamavir (Relenza). During clinical testing of oseltamivir in 2001, some individuals shed drug-resistant viruses with an amino acid change from histidine to tyrosine (H274Y) in NA. Such viruses are not inhibited …
Secondary changes allow spread of oseltamivir resistant influenza virus Read More »
When infection with hepatitis C virus goes from acute to chronic, severe liver disease may occur which requires organ transplantation. Nearly 200 million people are chronically infected with HCV, necessitating approaches to preventing and treating infections. No HCV vaccine is available, and current antiviral therapy consists of administration of interferon plus ribavirin, a combination that …
