Paramyxovirus: The Measles And Mumps

By Katie Duvall and Megan Cousins

General Characteristics

• Paramyxovirus is a virus.• Infections of measles and mumps occur

worldwide and are confined only to humans.• In most cases, they are all spread by the

aerosol route.• This virus is seen on the epidermis, in the form

of blotchy, red spots and rashes.• Eww.

History

• The word measles is derived from the German word for blister.• The word paramyxovirus is a compound of “para,” “myxo,” and

“virus.” The “myxo” is derived from the Greek “myxa” meaning mucus, slime.

• There were about 500,000 cases of the measles in the United States every year before the current vaccine.

• Since 1963, the number has fallen drastically. There were only 86 cases in 2001.

• The measles were discovered by Persian physician Muhammad ibn Zakariya ar-Razi (860-932).

• The virus was recognized by the Greeks, although it was only first isolated in 1934.

Structure

• The virus is an enveloped, non-segmented, negative- sense RNA virus.

• It has helical symmetry.• They can be spherical, filamentous or

pleomorphic.• Fusion and attachment proteins make the virus

look spiny. • There is a nucleocapsid core made of genomic

RNA, phosphoproteins and polymerase proteins.

Common Diseases From the Virus

• Measles – includes a four-day fever, cough, runny nose, and conjunctivitis. A few days after the fever begins, a rash appears first on the head then works its way down to cover the entire body. It starts red then turns brown before disappearing.

• Mumps – includes partoid inflammation, or inflammation of the face, fever, and headache. In rare cases, there’s soreness of ears and face and loss of voice.

Measles Mumps

Common Diseases Continued…

• Rubella – after the 14-21 day incubation period, a rash appears on the face and spreads throughout the body. It usually disappears in 3-4 days. Other symptoms include low fever, headache, conjunctivitis, joint pain and swollen glands. It rarely affects infants or people over 40 years of age.

Rubella

Replication

• The virus can replicate either in the cytoplasm or the nucleus, depending on the presence of the nucleocapsid proteins. (if they are present, the replication takes place in the nucleus if not, the cytoplasm).

• It hasn’t been discovered whether the virus has any effect on the host cell.

Paramyxovirus and the Host Cell

• The virions attach to the membrane of a host cell, and the envelope blends itself to it. The nucleocapsid is inserted into the host cell’s cytoplasm. Then, the negative-sense RNA is copied into individual messenger RNAs and a positive-sense RNA pattern which is used to create more negative-sense RNA. The new viruses are built, and they sprout from the cell membrane. This is how they become enveloped.

• The virus replicates through the lytic cycle.

Treatment

• There is no current treatment for the virus• There is a preventative vaccine, but once a

patient is diagnosed, there is no treatment.• The vaccine has been seen to cause autism in

some cases, but overall is very effective in keeping the virus out of the country, and out of our bodies.