Outbreak Alerts
Editor: Alyson Browett, MPH

Contributors: Christina Potter, MSPH, Lane Warmbrod, MS, MPH, and Rachel Vahey, MHS
The Johns Hopkins Center for Health Security is analyzing and providing updates, as needed, on the confirmed and suspected monkeypox outbreaks that have been identified in several non-endemic nations worldwide. If you would like to receive these updates, please sign up here.
Recent Outbreaks Update as of May 25, 2022 at 1:00pm ET

Monkeypox cases continue to be confirmed and suspected in multiple non-endemic countries, the largest recognized outbreak of monkeypox among people with no travel history to West or Central Africa, where the disease is endemic. As of 1:00pm ET, 229 cases have been confirmed in 19 countries—including Australia, Austria, Belgium, Canada, Czech Republic, Denmark, France, Germany, Israel, Italy, Netherlands, Portugal, Slovenia, Spain, Sweden, Switzerland, United Arab Emirates, the UK (England and Scotland), and the US—and at least 88 more cases are suspected, including in additional nations (Argentina, Finland).

The WHO said there is no evidence the monkeypox virus circulating now, which belongs to the West African clade, has mutated, based on genome sequencing of several cases. The agency said the atypical clusters in the current outbreak in non-endemic nations should be able to be brought under control through contact tracing and isolation. But experts also cautioned that more attention must be paid to African countries where the disease is endemic, to avoid what some are calling a double standard given that few people seemed to care about or recognize the disease’s impact until it began affecting people in wealthier nations.

Smallpox vaccines are about 85% effective in preventing monkeypox, as the viruses are related, and can be used as pre- and post-exposure prophylaxis. France and the UK are offering smallpox vaccination to close contacts of monkeypox cases, including household members and healthcare workers. Several nations are in discussions with Bavarian Nordic to order the company’s smallpox vaccine—known as Imvanex in Europe and Jynneos in the US—and Germany reportedly has ordered 40,000 doses.

The US National Strategic Stockpile (SNS) contains about 1,000 doses of Jynneos, a 2-dose vaccine that is US FDA-approved for smallpox and monkeypox. The SNS also contains about 100 million doses of another, older smallpox vaccine called ACAM2000, originally produced by Sanofi and now by Emergent BioSolutions, that carries more risk of adverse events. The US CDC is in the process of releasing the Jynneos vaccine for use among high-risk contacts of patients in the US. To date, 6 US states have reported confirmed or suspected cases (California, Florida, New York, Massachusetts, Utah, Washington). Additionally, the oral medication tecovirimat (TPOXX) could be used to treat individuals with confirmed monkeypox and is likely a better choice than the antiviral brincidofovir, based on safety and tolerability profiles.

The US CDC held a clinical outreach call for healthcare providers and issued a Level 2 travel alert this week, cautioning people traveling in North America, Europe, and Australia to avoid close contact with sick people and take other precautions, as well as seek medical care immediately if skin rash symptoms occur. Many of the cases in North America and Europe are associated with travel and attendance at festivals, parties, raves, and saunas. In the current outbreak, a predominance of cases is among men who have sex with men (MSM), although not exclusively, as other cases include household contacts of cases.

Typically, monkeypox virus is transmitted through close contact with skin lesions; body fluids, including respiratory droplets; and contaminated materials such as linens. Monkeypox is not considered to be a sexually transmitted infection (STI), which are generally passed through semen and vaginal fluid. But health agencies are warning that transmission can occur between sexual partners through intimate contact, regardless of sexual orientation, with the likely mode of transmission being contact with skin lesions or contaminated bedding. The European Centre for Disease Control and Prevention (ECDC) assessed the risk as “moderate” for persons with multiple sexual partners and low for the broader population. Public health experts and health advocates emphasize that anyone who has close contact with an infected person is at risk of contracting monkeypox, and the virus is not, nor should it be considered, a “gay disease.”