Explainer - How worried should we be about the monkeypox health emergency?

The move follows the declaration by the World Health Organization in July. A Reuters tally has counted more than 25,800 cases globally and three countries outside of Africa have reported deaths.

HOW DANGEROUS IS IT?

First identified in monkeys, the virus is transmitted chiefly through close contact with an infected person. It typically causes mild symptoms including fever, rash, swollen lymph nodes and pus-filled skin lesions. Severe cases can occur though people tend to recover within two to four weeks, according to the WHO.

Anyone can spread the virus, but the current outbreak outside of Africa is concentrated almost exclusively among men who have sex with men.

Monkeypox spreads primarily via intimate skin-to-skin contact, usually with someone who has an active rash, as well as via contact with contaminated clothes or bedding. It is not as easily transmitted as the SARS-CoV-2 virus that spurred the COVID-19 pandemic.

WHY IS IT AN EMERGENCY?

The United States hopes the public health emergency declaration will help it contain the disease before it becomes endemic. This status unleashes funding and gives health agencies regulatory flexibility that could help increase access to vaccines and treatments.

Health officials from several countries had urged the WHO to label monkeypox a public health emergency of international concern due to the quick escalation of cases and concerns it may become endemic in more countries.

The emergency declaration aims to spur global action and collaboration on everything from testing to the production and distribution of vaccines and treatments.

The fatality rate in preceding monkeypox outbreaks in Africa of the strain currently spreading has been around 1%, but so far this outbreak appears to be less lethal in the non-endemic countries, many of which have stronger healthcare infrastructure. Until this year, the viral disease has rarely spread outside Africa where it is endemic.

Scientists are trying to determine what caused the initial cases and if the virus has changed. Increased global travel as well as climate change have generally accelerated the emergence and spread of viruses, experts say.

Infectious disease experts say that years of financial neglect has left sexual health clinics on the frontline of the current monkeypox response ill-prepared to curb further spread.

PROTECTIVE MEASURES

Health officials say that people should avoid close personal contact with someone who has a illness presenting with a distinctive rash or who is otherwise unwell. People who suspect they have monkeypox should isolate and seek medical care.

Health officials have also been offering monkeypox vaccines to high-risk individuals and those that have recently been in close contact with an infected person.

Danish company Bavarian Nordic has a vaccine that goes by the brand name Jynneos, Imvamune or Imvanex - depending on geography. It has U.S. and European approval for the prevention of both smallpox and the closely related monkeypox.

An older vaccine, currently made by Emergent Biosolutions is called ACAM2000, but its uptake has been limited due to a severe side-effect warning.

Bavarian Nordic says it can produce 30 million doses of its vaccines - including the monkeypox one - each year, and has tapped a U.S.-based contract manufacturer to increase monkeypox vaccine capacity.

TREATMENT

Monkeypox symptoms often resolve on their own within weeks. Patients may receive extra fluids and additional treatment for secondary bacterial infections.