microbio 2125 unit 6 part 12 - Mumps (Epidemic Parotitis)

Etiological Agent:

Paramyxovirus (in the Paramyxoviruses group)

mumps virus

Distinguishing characteristics of etiological agent:

• Contains spikes for host cell attachment

• Possesses F (fusion) spikes that initiate cell-cell fusion, forming multinucleate giant cells (syncytia)

negative-sense ssRNA

Virulence Factor(s):

• F (fusion) spikes

• Ability to form syncytia

Predisposing Factors:

• Exposure to respiratory or salivary secretions

• No prior immunity

Transmission:

• Spread through salivary and respiratory secretions

• Humans are the only reservoir

Syndrome (signs + symptoms):

• Fever

• Muscle pain

• Malaise

• Painful swelling of one or both cheeks (parotid glands)

• In 20–30% of infected adult males: epididymis and testes may become infected (rarely causes sterility)

2-3 week incubation

Affected body region/system:

• Parotid salivary glands

• Occasionally epididymis and testes in adult males

Treatment:

• Symptom management: ice or heat for swelling, pain relievers

Prevention:

Live attenuated MMR vaccine

Other notes:

• 40% of infections are subclinical

• Long-term immunity after infection

• Incubation period: 2–3 weeks

• Approx. 300 cases/year in the U.S.