Monkey pox: Short update
Neuruppin, 30 May 2022
In May 2022, several countries outside Africa including Germany registered first cases of monkey pox. What is unusual about these cases is that affected persons had no history of travel to African countries, and secondly, that the disease appears to have been transmitted via sexual activity in many instances.
General: Monkey pox (agent: Monkeypox virus, MPXV) are a rare zoonotic disease with rodents as the natural reservoir. As a rule, it is transmitted by animal contact. Human-to-human transmission is rare according to current knowledge. Transmission involves close dermal or mucosal contact with infectious material from skin lesions of an infected person and also – less frequently – respiratory droplets/secretions. Two different variants are known to date: the west African and the central African type, whereby the latter is significantly more pathogenic with up to 10 % mortality among persons under 16.
Clinical aspects: First symptoms are fever, headache, muscle and back pain, swollen lymph nodes. Skin changes appear after several days, simultaneously passing through various stages from spot to pustule (macula, papula, vesicula, pustula) and ultimately dry up and come off (scabs are infectious, too). The rash is concentrated on face, palms and soles but may also affect the anogenital region. Incubation period is 5 to 21 days, duration of illness 2 to 4 weeks. Clinical progression of the west African variant is generally mild but may become severe in newborns, children, pregnant women, elderly persons and those with immune deficiencies.
- Prior to skin changes: Influenza, malaria, typhus abdominalis, syphilis, leptospirosis and hemorrhagic fever viruses
- Exanthematic stage: Chickenpox (as a rule, no infestation of palms and soles, no synchronicity of stages), shingles, scarlet fever, herpes simplex and other smallpox viruses.
Laboratory diagnostics indicated:
- Upon suspicion of infection with zoonotic pox viruses with corresponding symptoms, in connection with animal contacts or stay in an endemic area (central and west Africa).
- In the event of close contact with persons verifiably infected with monkey pox within 21 days prior to first symptoms.
- In male patients reporting sex with males (MSM) and showing unclear synchronous skin changes similar to pox (differentiation from chickenpox, shingles, herpes, syphilis etc.). Since May 2022, also without travel anamnesis in endemic areas, due to current outbreaks in various countries outside Africa.
Diagnostics: In Germany, the monkey pox virus is classified as Biosafety Level 3 (BSL-3), which means that it may only be handled in laboratories from level 3 upward, and therefore not in Brandenburg. Requests for diagnostics of suspected cases to be directed to: “RKI, Konsiliarlabor Pockenviren”, either via contact form or by phone (030-18754-2313/2763). Samples mailed to the RKI must be accompanied by the RKI consignment note.
Virus identification: from weeping skin spots, content of vesicles and pustules, scabs or swabs from skin changes and other sample material during the acute phase via PCR. Also possible: viral culture or electron-optical presentation. Serological detection of antibodies against the monkey pox virus from the serum is not immediately possible since orthopox viruses which may infect humans induce cross-reactive response. Antibody detection may therefore only be helpful in case of missing direct virus detection.
Therapy: Given strict indication, Tecovirimat 2x 600 mg for 14 days (adults), children 13-25 kg: 2 x 200 mg, children 25-40 kg: 2 x 400 mg, from 40 kg adult dose for 14 days respectively. See also STAKOB „Hinweise zur Therapie von Affenpocken“.
Reporting obligation: According to IfSG, medical personnel and laboratories are obliged to report cases of monkey pox.
Isolation: minimum of 21 days until scabs heal or fall off. Rules of hygiene need to be strictly adhered to. Avoid contact with house pets.
- Hand hygiene pursuant to KRINKO recommendation: hand disinfectant with efficacy spectrum “virucidal against enveloped viruses”.
- Personal protective equipment (PPE) recommended: protective gown, disposable gloves, at least close-fitting mouth-nose cover or breathing mask, safety goggles and hood (PPM).
- For direct patient care: at least FFP2 mask according to safety requirements, better: FFP-3 or PPM (https://www.rki.de/DE/Content/InfAZ/A/Affenpocken/Hygiene.html)
- Surface disinfection: disinfectant with documented virucidal effect (see RKI list of disinfectants). Comply with application time!
- Cleaning staff: daily cleaning and disinfection of rooms using PPE
- Avoid dispersion of infectious skin particles, e.g. when making the bed
- Waste disposal according to ASN 18 01 03
Further suggestions and updated information at:
Prof. Dr. med. Frank T. Hufert
Professor of Microbiology and Virology
Medical Director, Institute of Mikrobiology and Virology
Brandenburg Medical School Theodor Fontane
Phone: +49 3573 85901