Viruses of Animals

Viruses cause a number of economically importantThe paramyxoviruses Hendra virus (HeV) and Nipah
diseases in animals and birds. Some viruses of animalsvirus (NiV) have emerged in humans and livestock in
can cause human infection or can mutate to give riseAustralia and Southeast Asia. Both viruses are
to human infection. The SARS virus, which camecontagious, highly virulent, and capable of infecting a
from an animal source, led to an outbreak of humannumber of mammalian species and causing potentially
infection and highlights the significance of viruses thatfatal disease.
are harboured in animals. Influenza viruses, whichAvian Influenza
persist in their natural bird host, can sometimes infectA large variety of influenza A viruses infect wild
humans. The study of animal viruses contributes toaquatic birds. Occasionally viruses are transmitted
our understanding of viral infection in general.from these birds to other species and this may then
(Reference: Animal Viruses: Molecular Biology ISBN:cause devastating outbreaks in domestic poultry or
978-1-904455-22-6)give rise to human influenza pandemics.
Foot-and-Mouth Disease VirusBluetongue Virus
Foot-and-mouth disease virus (FMDV) is aBluetongue virus (BTV) causes serious disease in
picornavirus and is the cause of an acute systemiclivestock (sheep, goat, cattle). Partly due to this BTV
vesicular disease that affects cattle worldwide. It is ahas been in the forefront of scientific research and
highly variable and transmissible virus. The viralnow represents one of the best understood viruses
genome consists of a single stranded positive RNA.at the molecular and structural levels. It is a complex
Pestivirusesnon-enveloped virus with seven structural proteins
Pestiviruses cause diseases in animals such as Classicaland a double-stranded RNA genome. (Reference:
swine fever (CSF) and Bovine viral diarrhea/MucosalSegmented Double-stranded RNA Viruses ISBN:
disease (BVD/MD). These are notifiable diseases and978-1-904455-21-9)
eradication programms are in place in variousPorcine Circoviruses
countries around the world. Animal pestiviruses sharesPorcine Circoviruses (PCV) are the smallest viruses
many similarities with the human hepaciviruses.that can replicate autonomously in eukaryotic cells.
Pestiviruses can establish persistent infection whichThey are non-enveloped and spherical and contain a
often goes unnoticed.covalently closed and single-stranded DNA genome.
ArterivirusesTwo types of PCV are known. Porcine circovirus
This viruses are classified in the order Nidovirales.type 1 (PCV1) does not cause disease, but porcine
Arteriviruses are small, enveloped, viruses with ancircovirus type 2 (PCV2) causes Postweaning
icosahedral core containing a positive-sense RNAMultisystemic Wasting Syndrome (PMWS), a new
genome. Equine arteritis virus (EAV), porcineemerging and multifactorial disease in swine.
reproductive and respiratory syndrome virusAnimal Herpesviruses
(PRRSV), lactate dehydrogenaseelevating virus (LDV)Herpesviruses infect animals and man. There is a wide
of mice and simian hemorrhagic fever virus (SHFV) allvariety of different herpesviruses with different
belong to this family of viruses. The arteriviruses arebiological characteristics. In animals the most
very species specific although they share variousimportant herpesviruses belong to the
biological properties such as morphology, structuralAlphaherpesvirinae. Pseudorabies virus causes
proteins, genome organization, replication strategy,Aujeszky's disease in pigs and is extensively studied
and the ability to establish prolonged or persistentas a model for basic processes during lytic
infection.herpesvirus infection. Bovine herpesvirus 1 causes
Coronavirusesbovine infectious rhinotracheitis and pustular
These viruses are positive-strand, enveloped RNAvulvovaginitis. The avian infectious laryngotracheitis
viruses. Viruses in this group are important pathogensvirus is phylogenetically different from these two
of mammals and birds. They cause enteric orviruses.
respiratory tract infections in a variety of animalsAfrican Swine Fever Virus
including humans, livestock and pets. Severe acuteAfrican swine fever virus (ASFV) is a large
respiratory syndrome (SARS) is caused by adouble-stranded DNA virus which replicates in the
coronavirus called SARS-CoV. CoV based vectorscytoplasm of infected cells. It causes a viral
have potential in vaccine development and for genehaemorrhagic fever with high mortality rates in pigs,
therapy. (Reference: Coronaviruses: Molecular andbut persistently infects its natural hosts, warthogs,
Cellular Biology ISBN: 78-1-904455-16-5)bushpigs and soft ticks with no disease signs.
Hendra and Nipah Virus