Multi-country monkeypox outbreak in non-endemic countries - World Health Organization

Since 13 May 2022, cases of monkeypox have been reported to WHO from 12 Member States that are not endemic for monkeypox virus, across three WHO regions.

Based on currently available information, cases have mainly but not exclusively been identified amongst men who have sex with men (MSM) seeking care in primary care and sexual health clinics.

The situation is evolving and WHO expects there will be more cases of monkeypox identified as surveillance expands in non-endemic countries.

As of 21 May, 13:00, 92 laboratory confirmed cases, and 28 suspected cases of monkeypox with investigations ongoing, have been reported to WHO from 12 Member States that are not endemic for monkeypox virus, across three WHO regions (Table 1, Figure 1).

Geographical distribution of confirmed and suspected cases of monkeypox in non-endemic between 13 to 21 May 2022, as at 13:00.

Based on currently available information, cases have mainly but not exclusively been identified amongst men who have sex with men (MSM) seeking care in primary care and sexual health clinics.

Genome sequence from a swab sample from a confirmed case in Portugal, indicated a close match of the monkeypox virus causing the current outbreak, to exported cases from Nigeria to the United Kingdom, Israel and Singapore in 2018 and 2019.

The identification of confirmed and suspected cases of monkeypox with no direct travel links to an endemic area represents a highly unusual event.

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.

A suspected or probable case for which laboratory testing by PCR and/or sequencing is negative for monkeypox virus.

The identification of confirmed and suspected cases of monkeypox without any travel history to an endemic area in multiple countries is atypical, hence, there is an urgent need to raise awareness about monkeypox and undertake comprehensive case finding and isolation (provided with supportive care), contact tracing and supportive care to limit further onward transmission.

Based on currently available information, cases have mainly but not exclusively been identified amongst men who have sex with men (MSM) seeking care in primary care and sexual health clinics.  No deaths have been reported to date.

Any patient with suspected monkeypox should be investigated and if confirmed, isolated until their lesions have crusted, the scab has fallen off and a fresh layer of skin has formed underneath.

Increasing awareness among potentially affected communities, as well as health care providers and laboratory workers, is essential for identifying and preventing further secondary cases and effective management of the current outbreak.

The key objectives of surveillance and case investigation for monkeypox in the current context are to rapidly identify cases, clusters, and the sources of infection as soon as possible in order to provide optimal clinical care, isolate cases to prevent further transmission, identify and manage contacts and tailor effective control and prevention methods based on most commonly identified routes of transmission.

Because of the public health risks associated with a single case of monkeypox, clinicians should report suspected cases immediately to national or local public health authorities regardless of whether they are also exploring other potential diagnoses.

Probable and confirmed cases should be reported immediately to WHO through IHR National Focal Points (NFPs) under the International Health Regulations (IHR 2005).

Case reports should include at a minimum the following information: date of report; reporting location; name, age, sex and residence of the case; date of onset of first symptoms; recent travel history; recent exposure to a probable or confirmed case; relationship and nature of contact with probable or confirmed cases (where relevant); recent history of multiple or anonymous sexual partners; smallpox vaccination status; presence of rash; presence of other clinical signs or symptoms as per case definition; date of confirmation (where done); method of confirmation (where done); genomic characterization (if available); other relevant clinical or laboratory findings, particularly to exclude common causes of rash as per the case definition; whether hospitalized; date of hospitalization (where done); and outcome at time of reporting.

During human monkeypox outbreaks, close physical contact with infected persons is the most significant risk factor for monkeypox virus infection.

Laboratory confirmation of suspect cases is important but should not delay implementation of public health actions.

Retrospective cases cannot be laboratory confirmed; however, serum from retrospective cases can be collected and tested for anti-orthopoxvirus antibodies to aid in their case classification.

Samples taken from people with suspected monkeypox or animals with suspected monkeypox virus infection, should be safely handled by trained staff working in suitably equipped laboratories.

Clinical laboratories should be informed in advance of samples to be submitted from persons with suspected or confirmed monkeypox, so that they can minimise risk to laboratory workers and, where appropriate, safely perform laboratory tests that are essential for clinical care.

Contact tracing is a key public health measure to control the spread of infectious disease pathogens such as monkeypox virus.

In the current context, as soon as a suspected case is identified, contact identification and contact tracing should be initiated.

A contact is defined as a person who, in the period beginning with the onset of the source case’s first symptoms, and ending when all scabs have fallen off, has had one or more of the following exposures with a probable or confirmed case of monkeypox:.

If the contact develops a rash, they need to be isolated and evaluated as a suspected case, and a specimen should be collected for laboratory analysis to test for monkeypox.

Any health worker or household member who has cared for a person with probable or confirmed monkeypox should be alert to the development of symptoms that could suggest monkeypox infection, especially within the 21-day period after the last date of care.

Healthcare workers who have cared for or otherwise been in direct or indirect contact with monkeypox patients while adhering to recommended IPC measures may undergo self-monitoring or active monitoring as determined by local public health authorities.

Public health officials should work with travel operators and public health counterparts in other locations to assess potential risks and to contact passengers and others who may have had contact with an infectious patient while in transit.

This includes providing public health advice through the channels that target audiences use on how the disease transmits, its symptoms, preventive measures and what to do in case of suspect or confirmed infection

Large gatherings may represent a conducive environment for the transmission of monkeypox virus as they entail close, prolonged and frequent interactions among people, which in turn can expose attendees to contact with lesions, body fluids, respiratory droplets and contaminated materials

In addition, any person meeting the suspected, probable and confirmed case definition detailed above should refrain from close contact with any other individual and should not attend large gatherings

Health workers caring for patients with suspected or confirmed monkeypox should implement standard, contact and droplet precautions

Prompt isolation of suspected or confirmed cases in a single room with adequate ventilation, dedicated bathroom and staff is recommended