the study of viruses.
can infect almost any cell.
complete virus particle. Consists of one or more molecules of DNA or RNA, but not both.
simple, acellular organization and pattern of reproduction.
viruses are enclosed in a coat of protein called:
unable to reproduce independent of cells and carry out cell division as prokaryotes and eukaryotes do.
range in size from 10 to 300 or 400 nm in diameter
all, even if they posses other constituents, are constructed around a nucleocapsid core.
can cause the formation of an inclusion body within the cytoplasm and/or nucleus of the cell it infects.
collanies of viruses.
process of making a copy of a DNA molecule
reproduce through replication
strict intercellular parasites
smallest form of life known
known to cause hyperplasia of host cells
an increase in size and number of a cell
process by which viruses generally spread from host to host
inanimate object that can become contaminated
produces a long last immunity
elective localization/tissue affinity site
viral infections in humans can be classified according to:
Ex: Variola, varicella/varicella zoster, rubeola, rubella, herpes simplex I, herpes simplex II.
small pox. transmitted by droplet spray, enters respiratory tract, placental transfer possible. vaccination available. (dermotropic)
chicken pox. direct contact with droplet spray. enters respiratory tract, mild in children. (dermotropic)
varicella zoster/herpes zoster
shingles. reactivation of the chicken pox. Severe in adults. (dermotropic)
meales. transmitted by direct contact with droplet spray. enters the respiratory tract. (dermotropic)
produced by rubeola virus
german measles. 3 day measles. transmitted by direct contact with droplet spray. enters the respiratory tract. enlarges the liver and spleen. (dermotropic)
herpes simplex I
cold sores/fever blisters appear on the weather line of lips and nostrils. transmitted by direct contact with droplet spray (oral and respiratory secretions). enters the respiratory tract. (dermotropic)
herpes simplex II
genital herpes (herpes progenitalis). transmitted by direct contact with lesion exudates (pus). enters the genital urinary tract. linked to cervical cancer. (dermotropic)
Ex: influenza, cold virus, hantavirus
transmitted by direct contact with droplet spray OR indirect contact with fomites. enters the respiratory tract. opportunistic to bronchopneumonia. vaccine provides one year immunity (pneumotropic)
hong kong flu
common cold. transmitted by direct contact with droplet spray, enters the respiratory tract. no immunity. (pneumotropic)
most commonly occuring aliment in human beings
hantavirus pulmonary syndrome
transmitted by contact with contaminated dust from the nests or droppings of rodents. enters the respiratory OR digestive tract. (pneumotropic)
Ex: rabies, viral encephalitis, poliomyelitis
hydrophobia. transmitted by animal vectors, deep puncture wound, rarely aerosol infections. enters the skin. non-communicable disease. affects the CNS-causes possible paralysis. Fatal if left untreated. (neurotropic)
ARBO virus (arthropod borne). effects the brain. transmitted by deep puncture wounds, mostly by mosquito's, ticks, and flies. affects only man and horses. non-communicable. (neurotropic)
arthropod borne disease affecting the brain and spinal column.
paralytic polio (infantine paralysis) transmitted by direct contact with droplet spray, fecal/oral route. enters the respiratory tract or gastrointestinal tract. (neurotropic)
3 forms: subclinical (95% go unnoticed), non=paralytic, paralytic
Ex: hepatitis A, hepatitis B, hepatitis C, infectious mononucleosis, cytomegalovirus, epidemic parotitis virus
hepatitis type A virus
infectious hepatitis. transmitted by direct contact with contaminated feces, enters through any normal portal of entry. Symptoms: enlarged liver, jaundice condition of tissues, fever, nausea.(viscerotropic)
hepatitis type B virus
serum hepatitis. transmitted by direct contact with contaminated blood. enters through skin-deep puncture wound. endemic in intraveous drug use. (viscerotropic)
hepatitis type C virus
non A/ non-B hepatitis. transmitted though contaminated blood. enters though skin-deep puncture wound. (viscerotropic)
"kissing disease". transmitted by direct contact with droplet spray/saliva. rarely through a blood transfusion. enters the GI/ respiratory tract. (viscerotropic)
disease of glands, salivary and/or liver. transmitted by direct contact with saliva, urine, blood or bile. enters through respiratory/GI/GU tract. (viscerotropic)
epidemic parotitis virus
mumps. transmitted by direct contact with droplet spray. enters the respiratory tract.
Ex: HIV Virus, AIDS
AIDS. transmitted by direct contact with various bodily fluids. causes a reduction in immune defense. (immunotropic)