2. Rubella (German measles)
• is a viral disease of numerous organs caused by an RNA virus
and accompanied by a mild skin rash called
an exanthem. First appearing on the body trunk, the rash
spreads to other areas. Pregnant women may transmit the
virus across the placenta to the developing embryo or fetus,
and congenital rubella syndrome may develop in the
newborn. Damage to the eyes, ears, and heart often result.
Immunity can be rendered by an injection of attenuated
rubella virus in the MMR vaccine.
3. Measles
• Measles is also called rubeola. It is caused by an RNA
virus normally transmitted by respiratory droplets
during the coughing stage. Red spots with white
centers occur on the cheeks, gums, and lips and are a
diagnostic sign for the disease. These spots are
called Koplik spots. The measles skin rash appears as
a blush first on the forehead, then on the upper
extremities, trunk, and lower extremities. Prevention
is rendered by inoculation with attenuated measles
viruses in the MMR vaccine. Complications of the
disease may include measles encephalitis or subacute
sclerosing panencephalitis (SSPE).
4. Chickenpox.
• Chickenpox is also called varicella. The disease is
closely related to an adult disease called herpes
zoster (shingles).The responsible virus is a
DNA‐containing virus of the herpesvirus group. It is
also known as the VZ virus.
• Chickenpox is a highly contagious disease.
Transmitted primarily by respiratory droplets, the
disease is accompanied by teardropshaped lesions
filled with fluid. The lesions begin on the scalp and
trunk and then spread to the face and limbs.
Prevention is possible with injections of inactivated
VZ virus in the chickenpox vaccine.
5. Shingles
• occurs in adults and is believed to be a recurrence of infection by the
virus that causes chickenpox. Presumably, the virus has remained
latent in ganglia of the nervous system until it is reactivated. The
disease is characterized by painful lesions surrounding the body
trunk. The disease is highly contagious. Acyclovir may be
recommended for therapy.
6. Smallpox
• Smallpox is a viral disease caused by a large, boxlike, DNA‐containing
virus having a complex shape. At one time, smallpox was a major
cause of death in the world. It was accompanied by pus‐filled lesions
covering the body surface, and usually it resulted in death. Immunity
was rendered by an injection of cowpox (vaccinia) viruses, as first
recommended by Edward Jenner in 1798. Smallpox has apparently
been eradicated on the earth and has not appeared in humans since
October 26, 1977. It is the first infectious disease ever to be
eradicated.
7. Cowpox
• also known as vaccinia, is caused by a DNA virus similar in shape to
the smallpox virus. In barnyard animals, the virus causes a disease
accompanied by lesions of the skin. These lessons also occur when
humans are infected. Immunizations with cowpox viruses for
smallpox protection are no longer given.
8. Molluscum contagiosum.
• Molluscum contagiosum is a skin disease caused by a DNA‐containing
poxvirus. The disease is accompanied by flesh‐colored, painless
lesions scattered over the skin surface. The disease is transmitted by
skin contact.
9. Warts.
• Warts are considered an infectious disease caused by a number
of papilloma viruses, which contain DNA. Warts vary in appearance,
and are generally benign. However, certain types of warts can be
forerunners of malignancies. Cases of genital wartsare very
widespread, and certain strains of virus are related to cervical
cancers. Genital warts are transmitted by sexual skin contact. Other
kinds of warts, such as dermal warts, occur in the epithelial cells of
the skin tissues.