INTRODUCTION TO MUMPS VIRUS
⇒ MUMPS VIRUS is the causative agent of disease MUMPS, an acute infectious disease commonly affecting children and characterized by Parotitis (inflammation of parotid glands).
⇒ It had been described by Hippocrates in the fifth century BC as ‘Epidemic Parotitis’.
⇒ This virus belongs to the Rubulavirus genus of Paramyxoviridae
MORPHOLOGY OF MUMPS VIRUS
⇒ It Resembles orthomyxovirus in morphology – Spherical, Enveloped virus with helical Nucleocapsid (13-18 nm).
⇒ Size: 100-250 nm in diameter.
⇒ The envelope is covered by projections of HN (Hemagglutinin, Neuraminidase) and F (Fusion protein) peplomers.
⇒ Genetic Material:- Linear ssRNA
⇒ There is only one serotype of Mumps virus.
RESISTANCE SHOWN BY MUMPS VIRUS
⇒ The mumps virus is labile, rapidly inactivates at room temperature.
⇒ Exposure to formaldehyde, ether or ultraviolet light inactivates the virus particle.
⇒ It can be preserved at –70oC or by lyophilization.
PATHOGENESIS OF MUMPS VIRUS
⇒ This virus causes the disease mumps, an acute infectious disease characterized by non-suppurative enlargement of the parotid gland and Parotitis.
The virus is Acquired by Inhalation and
through the conjunctiva.
The virus replicates in upper respiratory tract &
Cervical lymph nodes.
Disseminated through the bloodstream to
Various organs cause swelling & Inflammation.
CLINICAL FEATURES OF MUMPS VIRUS INFECTION
⇒ The incubation period of this virus is 12-25 days.
⇒ Parotid swelling is usually the first sign of illness preceded by Malaise
⇒ It is accompanied by Fever, Local pain, and tenderness of parotid gland and Parotitis.
⇒ Epididymo-orchitis and Meningoencephalitis are important complications of Mumps.
⇒ Other less common complications are Arthritis, Oophoritis, Nephritis, Pancreatitis, Thyroiditis, and Myocarditis.
LABORATORY DIAGNOSIS OF MUMPS VIRUS
⇒ Specimen: Saliva, Throat secretions, CSF and Urine.
⇒ Direct Demonstration: Immunofluorescence on secretions of throat and saliva.
⇒ Isolation of the virus: Virus can be isolated from saliva, Throat swab, CSF or urine by inoculating into Primary monkey Kidney, HEp-2 or in Human Amnion.
⇒ Serology: Mumps specific IgM antibodies can be detected in serum by ELISA. Hemagglutination Inhibition Test and Neutralization Test can also be done.
PROPHYLAXIS OF MUMPS VIRUS
⇒ MMR, a live attenuated, vaccine is available. It can be administered subcutaneously and is a combination of attenuated Mumps, Measles and Rubella vaccine.
⇒ This vaccine is given to children aged 12-15 months.
⇒ It provides effective protection for at least 10 years.