Monkeypox (PCR)

Smear

Mpox is caused by the monkeypox virus (MPXV), an enveloped DNA virus of the genus Orthopoxvirus.

Infection with the virus is often characterised by the appearance of one or more non-specific symptoms such as fever, chills, muscle aches, headaches, fatigue or joint pain. These symptoms can precede the appearance of the typical skin lesions as a prodromal phase, but they can also appear after them or be completely absent. In more than half of the cases, there is often painful lymphadenopathy, usually in the groin area, which accompanies the skin lesions.

Transmission occurs through droplet infection, direct contact of skin or mucous membranes with body fluids or the typical skin lesions (so-called smallpox lesions), whereby both vesicle contents and scabs are infectious. The smallpox lesions contain particularly high concentrations of the virus. It should be noted that lesions on mucous membranes are often not visible from the outside. Starting from smallpox lesions in the mouth, the infectious virus can enter saliva and respiratory secretions. Maternal-foetal transmission can occur via the placenta. Transmission via contaminated objects such as clothing, bed linen, towels or, in special cases, via surfaces that have been contaminated with the virus through contact with infectious scabs or smallpox blister contents of an infected person, has so far been described mainly in endemic areas.

The incubation period is 1 to 2 weeks, but can also be up to 3 weeks. The risk of infection begins with the appearance of the first symptoms and lasts until all lesions have crusted over and the scabs have fallen off to reveal healthy skin. This usually takes 2 to 4 weeks.


Currently, the most sensitive and fastest detection of poxviruses is the nucleic acid detection of MPXV using real-time PCR (rtPCR) from samples of skin lesions (coating or fluid from vesicles and pustules and/or dry crusts). Blood is not recommended as a material for PCR due to the short duration of viraemia.