Monkeypox Outbreak Toolbox. May 2022

CASE DEFINITIONS: WHO suggested an outbreak case definition Suspected case: A person of any age presenting in a monkeypox non-endemic country with an unexplained acute rash. One or more of the following signs or symptoms, since 15 March 2022: • Headache • Acute onset of fever (>38.5oC), • Lymphadenopathy (swollen lymph nodes) • Myalgia (muscle and body aches) • Back pain • Asthenia (profound weakness) For which the following common causes of acute rash do not explain the clinical picture: varicella zoster, herpes zoster, measles, Zika, dengue, chikungunya, herpes simplex, bacterial skin infections, disseminated gonococcus infection, primary or secondary syphilis, chancroid, lymphogranuloma venereum, granuloma inguinale, molluscum contagiosum, allergic reaction (e.g., to plants); and any other locally relevant common causes of papular or vesicular rash. N.B. It is not necessary to obtain negative laboratory results for listed common causes of rash illness in order to classify a case as suspected. Probable case: A person meeting the case definition for a suspected case. One or more of the following: • has an epidemiological link (face-to-face exposure, including health workers without eye and respiratory protection); direct physical contact with skin or skin lesions, including sexual contact; or contact with contaminated materials such as clothing, bedding or utensils to a probable or confirmed case of monkeypox in the 21 days before symptom onset • reported travel history to a monkeypox endemic country1 in the 21 days before symptom onset • has had multiple or anonymous sexual partners in the 21 days before symptom onset • has a positive result of an orthopoxvirus serological assay, in the absence of smallpox vaccination or other known exposure to orthopoxviruses • is hospitalized due to the illness Confirmed case: A case meeting the definition of either a suspected or probable case AND is laboratory confirmed for monkeypox virus by detection of unique sequences of viral DNA either by real-time polymerase chain reaction (PCR) and/or sequencing Discarded case: A suspected or probable case for which laboratory testing by PCR and/or sequencing is negative for monkeypox virus WHO surveillance case definition Suspected case: • An acute illness with fever >38.3⁰C (101⁰F), intense headache, lymphadenopathy, back pain, myalgia and intense asthenia followed one to three days later by a progressively developing rash often beginning on the face (most dense) and then spreading elsewhere on the body, including soles of feet and palms of hands. Probable case: • A case that meets the clinical case definition, is not laboratory confirmed but has an epidemiological link to a confirmed or probable case. Confirmed case: • A clinically compatible case that is laboratory confirmed.