What is unique about poxviruses?
The replication of poxvirus is unusual for a virus with double-stranded DNA genome because it occurs in the cytoplasm, although this is typical of other large DNA viruses. Poxvirus encodes its own machinery for genome transcription, a DNA dependent RNA polymerase, which makes replication in the cytoplasm possible.
Which 3 of the following poxviruses can infect humans?
Molluscipoxviruses include the human poxvirus, molluscum contagiosum virus. Smallpox and molluscum contagiosum are specific to humans. The other viruses cause rare zoonotic infections in humans. Vaccinia virus, which has been used for vaccination, can also infect humans.
Which of the following diseases are caused by poxviruses in humans?
The parapoxviruses causing human disease include orf, bovine papular stomatitis, and sealpox. Many other genera of poxviruses have recently been discovered but are primarily pathogens in wild animals, so human disease is extremely rare or is not yet identified.
What poxviruses are zoonoses?
Three genera of Poxviridae are known to cause human zoonoses: orthopoxviruses, parapoxviruses and yatapoxvirus. Most cases are occupational, sporadic and have few cutaneous lesions with low morbidity. The exception is monkeypox, similar to smallpox, with significant morbidity and childhood mortality.
How are poxviruses transmitted?
Poxviruses are transmitted between individuals by several routes: by aerosol and droplets (variola virus), by introduction of virus into small skin abrasions after direct or indirect contact with an infected animal (orf virus, milker’s nodule virus), and in the case of some animal poxviruses mechanically by biting …
What pathogen causes poxviruses?
The most well known member of the genus is variola virus, the causative agent of smallpox. Other notable members include vaccinia virus which is used in the current smallpox vaccine; cowpox virus, first introduced by Edward Jenner in the late 18th Century as the material of the first vaccine; and monkeypox virus.
Do poxviruses replicate in the nucleus?
The poxviruses are the only DNA genome viruses that replicate and express their genome in the cytoplasm (rather than in the nucleus) of the infected cell.
How are viruses grouped or classified?
Viruses are classified by phenotypic characteristics, such as morphology, nucleic acid type, mode of replication, host organisms, and the type of disease they cause.
What type of virus is coronavirus?
Coronaviruses are a type of virus. There are many different kinds, and some cause disease. A coronavirus identified in 2019, SARS-CoV-2, has caused a pandemic of respiratory illness, called COVID-19.
What are the different types of poxviruses?
These include monkeypox virus, orf virus, molluscum contagiosum, and others. While some poxviruses, such as smallpox (variola virus), no longer exist in nature, other poxviruses can still cause disease.
How do poxviruses infect humans?
Infection in humans usually occurs due to contact with contaminated animals, people, or materials. While some poxviruses, such as smallpox (variola virus), no longer exist in nature, other poxviruses can still cause disease. These include monkeypox virus, orf virus, molluscum contagiosum, and others.
Are poxviruses highly virulent only to humans?
However, at the level of individual viruses, even closely related poxviruses display highly diverse host ranges and virulence. For example, variola virus, the causative agent of smallpox, is human-specific and highly virulent only to humans … Poxviruses and the evolution of host range and virulence Infect Genet Evol.
What is the Poxviridae family?
Poxviridae is a family of viruses. Humans, vertebrates, and arthropods serve as natural hosts. There are currently 83 species in this family, divided among 22 genera, which are divided into two subfamilies.