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Question 1

Measles: Cause

Answer 1

Often affects susceptible children as an acute, highly infectious, often epidemic disease.
Caused by PARAMYXOVIRUS.
-Negative-strand RNA virus.
Virus enters the nose and throat by airborne transmission.

Question 2

Measles: Facts

Answer 2

Used to be common childhood illness.
Now only occurs in isolated outbreaks
-Due to widespread immunization programs that began in the mid 1960’s.
Still over 100,000 deaths per year worldwide.
Proof of immunization required for enrollment in U.S. public schools.

Question 3

Mumps

Answer 3

Caused by paramyxovirus (like measles).
Highly infectious.
Spread by airborne droplets.
Characterized by inflammation of salivary glands.

Question 4

Rubella

Answer 4

German measles or 3-day measles.
Caused by positive-strand RNA virus of toga virus group.
Disease symptoms resemble measles but generally milder and less contagious.
Routine childhood immunization practiced in U.S.

Question 5

Colds

Answer 5

Most common infectious disease.
Viral infections transmitted via airborne droplets.
Infections usually of short duration.
Symptoms milder than other respiratory diseases.
Symptoms include rhinitis, nasal obstruction, watery nasal discharges and malaise.

Question 6

The common cold

Answer 6

Commonly caused by rhinovirus
-Positive sense, single stranded RNA viruses.
-Nearly 115 different strains identified.
Approximately 15% of colds due to coronaviruses.
Approximately 10% of colds due to other viruses.

Question 7

No cure for the common cold

Answer 7

Most antiviral drugs ineffective against common cold.
-pyrazidine derivatives and rhinovirus receptor blocking drugs have shown promise.
Each cold infection induces specific, protective immunity, but preclude protective immunity.

Question 8

Influenza

Answer 8

Influenza caused by an RNA virus of orthomyxovirus group.
Three different types (A,B,C).
-A kills the most and is most important.

Question 9

Influenza: Mutations

Answer 9

Influenze outbreaks occur annually due to plasticity of influenza genome.

• Antigenic drift: minor change in influenza virus antigens due to gene mutation.
• Antigenic shift: major change in influenza virus antigen due to gene reassortment.

Question 10

Reassortment Virus

Answer 10

Swine infected with bird virus and human virus.

-Reassortment of human and bird virus.