Before the availability of rotavirus vaccines, rotaviruses were the most common cause of severe infant and childhood gastroenteritis worldwide, responsible for 40% of all diarrheal hospitalizations and more than half a million deaths among children aged <5 years annually. To…
Colorado tick fever (CTF) is an acute febrile illness caused by CTF virus, a double-stranded RNA virus in the Coltivirus genus of the family Reoviridae ( Box 215.1 ). , The virus is transmitted to humans through the bite of…
Parvoviruses—small (20–25 nm), nonenveloped, icosahedral, single-stranded DNA viruses with a linear genome of between 4500 and 5600 nucleotides—are common infectious agents of animals, including birds and insects, as well as humans. At least five different genera of parvovirus have been…
Hepatitis B Virus Description of the Pathogen Hepatitis B virus (HBV), a member of the Hepadnaviridae family, is an enveloped virus that contains a circular partially double-stranded DNA genome that is 3.2 kb in length. The small genome consists of…
Polyomaviruses are a subgroup of small, ubiquitous DNA viruses that belong to the family Papovaviridae. The two most commonly known human polyomaviruses are the BK virus and JC virus, which were first described in 1971. , Subsequently, 12 other human…
Papillomaviruses are species specific and widely distributed among mammals and nonmammalian animal species. Human papillomaviruses (HPVs) are strictly epitheliotropic and cause infections and cancer of the skin and mucous membranes. Clinical conditions include anogenital and oral infections and cancers, as…
Acknowledgement The author acknowledges substantial contributions of Gail J. Demmler-Harrison to this chapter in previous editions. Adenoviruses are relatively small, nonenveloped double-stranded DNA viruses belonging to the family Adenoviridae (from adenos, the Greek word meaning “gland”). They were first isolated…
In 1872, Moritz Kaposi, a Hungarian dermatologist, first described in five men an aggressive, pigmented, multicentric sarcoma of the skin that disseminated to multiple sites. It was rare and received little attention until similar lesions were observed in African children…
Epstein-Barr virus (EBV), a ubiquitous herpesvirus of humans, was discovered in 1964. The causal relationship between EBV and infectious mononucleosis (IM) was observed in 1968. The spectrum of associated infections ranges from asymptomatic to self-limited mononucleosis in healthy hosts to…
Human Herpesvirus 6 Human herpesvirus 6 (HHV-6) was first isolated from the peripheral blood lymphocytes of adults with lymphoproliferative diseases and HIV infection and was named human B-lymphotropic virus. When additional isolates were identified in CD4 + lymphocytes, further characterization…