Transcript MUMPS
MUMPS XIE QIFENG Dept. of Infectious Disease Introduction Mumps is an acute respiratory tract infectious disease caused by mumps virus, it occurs primarily in school-aged children and adolescents.The most prominent manifestation is nonsuppurative swelling and tenderness of the salivary glands with one or both parotid glands involved in most cases. Introduction Meningitis, meningoencephalitis, epididymo-orchitis, oophoritis and pancreatitis are the common extrasalivary gland manefestations of mumps. Etiology • Mumps virus (Paramyxovirus parotitis) belongs to Paramyxoviridae family. RNA virus. • 6 major proteins. nucleocapsid associated (S antigen) for diagnosis. Hemagglutininneuraminidase(V antigen) for protection. Etiology • Sensitive to ether,ultraviolet and high temperature • Humans are the only natural host Epidemiology • Sources of infection: Patients in early course of the disease, hosts under covert infection. The period of peak contagion before or at the onset of parotitis. • Route of transmission : Via droplet nuclei or direct contact,fomites • Epidemic features: Endemic throughout the world. The peak incidence in winter and spring. School-aged children at high risk. Post-infection immunity is stable and long-lasting. Pathogenesis and Pathology The virus usually infecting glandular tissue such as parotid, orchis or oophoron. The main pathologic findings are nonsuppurative inflammatory reactions. The meningoencephalitis may involve the Fusion protein. Clinical Manifestations • Incubation period: averages 16 to 18 days with a range of 2 to 4 weeks. • Prodromal symptoms include low- grade fever, anorexia,malaise and headache. • Parotid tenderness and ipsilateral earache within 1 or 2 days after the illness onset,then parotid is visibly enlarged and go to maximum size over next 2 to 3 days accompanied severe pain and normal or high temperature. One parotid enlarges after the other. The orifice of Stensen’s duct is edematous and erythematous. Parotid returns to normal size within a week. Patients with parotitis have difficulty with pronunciation and mastication. Citrus fruits and juices exacerbates the pain. Other salivary glands involved include submandibular adenitis and sublingual adenitis. • Clinical meningitis occurs in 15% of patients with mumps. Its onset averages 4-5 days after parotitis but may before, after or in the absence of parotitis. Clinical features are headache, vomiting, fever and nuchal rigidity. CSF pleocytosis. Prognosis is benign. • The onset of orchitis is abrupt with high temperature, chills , testicular pain and swelling. Impaired fertility is rare. • Oophoritis develops in 5% postpubertal women with mumps. Impaired fertility is rare. • Pancreatitis is manifested by severe epigastric pain and tenderness,fever,nausea,and vomiting. Diagnosis • In most instances, the diagnosis of mumps is made on the basis of a exposure history and of parotid swelling and tenderness accompanied other symptoms. • Laboratory confirmation is unnecessary in typical cases, exception the absence or recurrence of parotitis and extrasalivary glands involved. Serologic tests,viral isolation. Amylase and lipase. Differential Diagnosis • Suppurative parotitis • Other viral parotitis: caused by parainfluenza virus, coxsackievirus and influenza A virus. ---serologic tests or viral culture • Parotid enlargement caused by other reasons Prognosis Benign and self-limited Major death causes are severe mumps encephalitis Treatment • Supportive and symptomatic treatment • Anti-viral therapy: ribavirin and interferon • Dexamethason for meningoencephalitis • Diethylstilbestrol for orchitis Prenvention • Patients should be isolated. • Attenuated mumps virus vaccine has been available. More than 90% vaccine recipients produced protective antibody. Aseptic meningitis associated with vaccine virus occurred in 0.025% recipients. Mumps vaccine should not be administered to pregnant women or persons with immunodeficiencies. Thanks!