Mumps virus - MegaMicro

o   Enveloped, helical, single-stranded, non-segmented, negative sense RNA virus

o   Transmitted by respiratory droplets, it attaches and invades upper respiratory tract epithelium via viral hemagglutinin (HA) envelop proteins which leads to viremia.

§  Incubation: 2-3 week period

§  Infects glandular tissue (parotid gland, testes)

·         Inflammatory infiltration and edema leads to painful enlargement of glands

§  If the virus spreads to meninges, it can lead to aseptic meningitis.

§  Virulence factors:

·         HA (binds sialic acid/cleaves sialic acid interaction)

·         M-protein (involved in envelope assembly)

·         Fusion (F) protein (causes infected cells to fuse)

o   Common to all Paramyxoviridae, cause infected cells to form multinucleate giant cells.

o   Worldwide. Outbreaks are seasonal with a winter/spring peak. Spread by direct contact, droplets, or fomites, and has a 2-3 week incubation.

o   Symptoms

o   Detection of virus in saliva, urine, CSF and serum

o   Serology (RT-PCR assays)

o   Parotitis asymmetric orchitis (sometimes can effect both testes leading to sterility) pancreatitis, aseptic meningitis. Other symptoms include fever, headache, and malaise

·         Aseptic meningitis is most commonly caused by coxsackievirus, echovirus and mumps virus

§  Supportive care including: analgesics, compression of parotids

§  Patients gain lifelong immunity after one infection.

§  Live-attenuated rubella virus in MMR vaccine

·         MMR vaccine is the only live vaccine that can be given to HIV positive individuals.