The document summarizes key information about two families of DNA viruses: Adenoviridae and Herpesviridae. Adenoviruses have a non-enveloped icosahedral capsid containing linear double-stranded DNA. They cause respiratory, gastrointestinal, and eye infections in humans. Herpesviruses have an enveloped nucleocapsid containing linear double-stranded DNA. They establish latent infections and cause diseases like chickenpox, mononucleosis, and shingles. Both virus families are able to integrate into host cell DNA and cause cancer in some cases.
48. CMV infection characteristic Immuno-deficient adults Newborns Fetuses Affected objects Systemic disease with fever, severe diarrhea, hepatitis, pneumonia, and high mortality Sexual contact, blood transfusion CMV mono-nucleosis Chiefly asymptomatic, although pneumonitis and a mononucleosis-like syndrome can develop during the first 3 months after birth During exposure to the motherโs vagina Perinatal CMV infection Most infected newborns are born without signs, a certain number exhibit enlarged liver and spleen, capillary bleeding, microcephaly. In some cases death follows within a few days or weeks. Rarely - sequelae, including hearing and visual disturbances and mental retardation. Trans-placental Congenital CMV infection Features Trans-mission Form of infection
50. Subfamily Gamma-herpesvirinae Rhadino - virus Lympho - cryptovirus Genus Kaposiโs sarcoma (a common tumor of AIDS patients). Possible: multiple myeloma, cancer of the blood Human herpevirus 8 (or Kaposiโs sarcoma-associated herpesvirus) Infectious mononucleosis, Burkittโs lymphoma, nasopharyngeal carcinoma. Hairy leucoplakia (in AIDS patients) Epstein-Barr virus (EBV) ะะฐัะพะปะพะณัั Viruses
51. Infectious mononucleosis Angina when infectious mononucleosis The symptoms of infectious mononucleosis are sore throat, high fever, and cervical lymphadenopathy, which develop after a long incubation period (30-50 days). Many patients also have a gray-white exudate in the pharynx
52. Burkittโs lymphoma Burkittโs lymphoma is a B-cell malignancy that usually develops in the jaw and grossly swells the cheek. African children 4 to 8 years old are usually affected
55. Blood smear of a patient with infectious mononucleosis. Lymphocytes infected by EDV
56. Important features of common herpesvirus infections Via respiratory secretions Zoster Cranial or thoracic sensory ganglia Varicella VSV Sexual contact, perinatal infection Herpes genitalis Lumbar or sacral sensory ganglia Herpes genitalis, perinatal herpes HSV-2 Via respiratory secretions and saliva Herpes labialis, encephalitis, keratitis Cranial sensory ganglia Gingivo-stomatitis HSV-1 Route of transmission Recurrent infection Usual site of latency Primary infection Virus
57. Important features of common herpesvirus infections Intrauterine infection, transfusions, sexual contact, via secretions (eg, saliva and urine) Asymptomatic shedding Uncertain Congenital infection, mono-nucleosis CMV Via respiratory secretions and saliva None B lympho-cytes Infectious mono-nucleosis EBV Route of transmission Recurrent infection Usual site of latency Primary infection Virus
Herpesvirus* was named for the tendency of some herpes infecยญtions to produce a creeping rash. Like other enveloped viruses, herpesviruses are prone to deactivation by organic solvents or detergents and are relยญatively unstable outside the host's body.
Approximately half of all adenovirus infections are asymptomatic. As for treatment, there is no antiviral therapy
Certain serotypes of human adenoviruses cause sarcomas at the site of injection in laboratory rodents such as newborn hamsters and transform rodent cells in culture. There is no evidence that adenoviruses cause tumors in human, and no adenoviral DNA has been detected in the DNA of any human tumor cells.
Herpesvirus* was named for the tendency of some herpes infecยญtions to produce a creeping rash. Like other enveloped viruses, herpesviruses are prone to deactivation by organic solvents or detergents and are relยญatively unstable outside the host's body.
The virion obtains its envelope by budding through the nuclear membrane and exits the cell via tubules or vacuoles that communicate with the exterior. In the latently infected cells, multiple copies of HSV-1 are found in the cytoplasm of infected neurons.
The relationship between varicella (chickenpox) and zoster (shingles) and the clinical appearance of each is exist. First contact with the virus (usually in childhood) results in a macular, papular, vesicular rash distributed primarily on the face and trunk, (b) The virus becomes latent in the dorsal ganglia of nerves that supply dermatomes of mid-thoracic nerves and the cranial nerves that supply facial regions, and as result we can see the clinical appearance of shingles. Early symptoms are acute pain in the nerve root and redness of the dermatome, followed by a vesicular-papular rash on the chest and back that is usually asymmetrical and does not cross the midline of the body
Wherever human populaยญtions have been tested, a relatively high percentage (40-100%) have shown the presence of antibodies to CMV developed during a prior infection. Studies in the United States and the United Kingdom revealed infection in 7.5% of newborns, making CMV the most prevalent viral infection in the fetus. Transmission of CMV usually involves intimate exposure such as sexual contact, vaginal birth, transplacental infection, blood transfusion, and organ transplantaยญtion. As with other herpesviruses, CMV is commonly carried in a latent state in various tissues. Because of the association of HHV-6 with cases of brain infection and encephalitis, it has been considered as a potential cause of chronic neurological disease. Researchers have recently established a link between this virus and multiple sclerosis (MS).
Most healthy adults and children with primary CMV infection are asymptomatic. However, three groups that develop a more virulent form of disease are fetuses, newborns, and immunodeficient adults.
the cytomegaloviruses* (CMVs), are named for their tendency to produce giant cells with nuclear and cytoplasmic inclusions. These viruses, also termed salivary gland virus and cytomegalic inclusion virus
Direct oral contact and contamination with saliva are the principal modes of transmission. Transmission by means of blood transfusions and organ transplants is also possible. The nature of infection depends on the patient's age at first exposure, socioeconomic level, geographic region, and genetic predisposition. In less-developed regions of the world, infection rates are generally higher and infection occurs at an earlier age. Children living in eastern and west-central Africa are predisposed to Burkitt's lymphoma, and residents of parts of China and North Africa show high levels of nasopharyngeal carcinoma, another tumor linked to EBV. In industrialized countries human usually develop infectious mononucleosis.