Measles virus

The measles virus ( MeV) is an exclusively human pathogen approximately 120-140 nanometers large causative agent of measles in the family Paramyxoviridae ( genus Morbillivirus ). The only reservoir formed by the infected person. Experimentally, dogs can become infected form (despite the relationship with the causative agent of canine distemper ), but no symptoms of.

Features

The measles virus has emerged evolutionarily from the rinderpest probably in the 11th or 12th century AD. It has a viral envelope glycoprotein hemagglutinin ( H protein ), a fusion protein ( F protein ) as well as on the inside of a matrix protein ( M protein) includes, but not neuraminidase. These surface proteins are responsible for the fusion with the host cell and uptake by this. The receptor through which the virus is incorporated into the human cells are CD46 and CD150. The damage induced by the vaccination ( induced ) antibodies directed against the surface proteins of measles virus, in particular the H protein.

Due to the viral envelope, the measles virus is very sensitive to external influences such as elevated temperatures, light, ultraviolet radiation, fat solvents and disinfectants and mild detergents. In air, his survival time is only two hours. It has a high infectivity ( contagion index ) of about 95%.

The WHO defines more than 20 genotypes (variations of genetic information ) into eight groups (A -H), which are relatively stable, which allows traceability of the global routes of infection in Central Europe mainly occur the stable genotypes C2 and D6. The stable serotypes with their consistent combination of surface features would also allow the production of a highly effective vaccine.

Transmission

The virus is transmitted by person to person, so it is theoretically eradicated. It spreads by droplet infection (coughing, sneezing, speaking) or direct human contact. Infection is possible even for short time exposure, the contagion index is 0.95. This means that infect 95 % of all people without adequate immunity and subsequently develop clinical symptoms.

Pathogen detection

The indirect detection of pathogens carried by the detection of specific antibodies by ELISA or CFT ( complement fixation ). The detection of the viral RNA is complicated and takes place only in special laboratories; he is only useful when a suspected Subacute sclerosing panencephalitis after a measles infection and is performed with cerebrospinal fluid as a sample material.