Tags: Ribavirin

Papovaviruses

Papillomaviruses (HPVs) cause skin warts, most commonly in children and young adults, which may reflect acquired immunity in older age groups (Box 1). Laryngeal papillomas are found most commonly in young children and middle-aged adults. Genital warts (condylomas) are most common among sexually active patients and are sexually transmitted. Recent studies suggest that genital HPV infections may occur in 20% of females and are associated with cervical dysplasia, neoplasia, or both.

Colorado Tick Fever

Colorado tick fever, an acute disease characterized by fever, headache, and severe myalgia, was originally described in the nineteenth century and is now believed to be one of the most common tick-borne viral diseases in the United States. Although hundreds of infections occur annually, the exact number is not known because it is not a reportable disease.

Hantaviruses

Hantaviruses are members of the bunyavirus group, which is the largest family of viruses and contains several human pathogens including California encephalitis virus (see site). The hantavirus group was first recognized as causing hemorrhagic fevers with renal failure in Asia and Eastern Europe but became much more prominent in the United States when the hantavirus pulmonary syndrome was described in the United States. Hantaviruses have been found throughout the world in a variety of rodents and other species.

Marburg & Ebola Virus

Two unique RNA viruses, the Marburg and Ebola viruses, are members of a new family known as filoviruses. These agents can cause severe or fatal hemorrhagic fevers and are endemic in Africa. Laboratory workers have been exposed to the Marburg agent while working with tissue cultures from African green monkeys.

Dengue & Yellow Fever

Dengue and yellow fever are both caused by flaviviruses, and each is spread by an arthropod vector. The etiologic agents of dengue are the dengue virus types 1-4, whereas yellow fever is caused by the yellow fever virus. Flaviviruses produce a wide range of diseases including hemorrhagic fevers, arthritis, encephalitis, and hepatitis.

Hepatitis

The causes of hepatitis are varied and include viruses, bacteria, and protozoa, as well as drugs and toxins (eg, isoniazid, carbon tetrachloride, and ethanol). The clinical symptoms and course of acute viral hepatitis can be similar, regardless of etiology, and determination of a specific cause depends primarily on the use of laboratory tests (Box 1). Hepatitis may be caused by at least six different viruses whose major characteristics are summarized in Table 1. Non-A-non-B (NANB) hepatitis is a term previously used to identify cases of hepatitis not caused by hepatitis A or B.

Parainfluenza Virus

Parainfluenza is a ubiquitous virus. It is the primary cause of acute laryngotracheobronchitis (croup) in children aged 6 months to 3 years. It is capable of infecting the lower respiratory tract as well by manifesting as bronchiolitis or pneumonia. Outbreaks can follow regular epidemic patterns or be sporadic. Certain antigenic types (described below) do follow epidemic patterns.