1st Clade Ib MPox Case in US

Hello Delaware County Medical Society healthcare providers,

As you may have seen in the news, the 1st confirmed clade 1b mpox case in the United States was reported in California on 11/16/24. This case is travel-related to the clade 1b outbreak in Central and Eastern Africa. Mpox spreads through close or intimate contact with a person with mpox. This could mean living in close quarters, or it may mean through sexual contact with a person with mpox. The risk of clade I mpox to the public remains low. The Centers for Disease Control and Prevention (CDC) is working closely with state/local authorities to identify close contacts to the California case. The individual returned from travel to East Africa and is isolating appropriately at home with clinical improvement. CDC issued a Health Alert Network update on this topic on 11/18/24.

There are two kinds of the virus that causes mpox, clade I and clade II. Each clade of the virus has subclades, clade Ia and clade Ib; clade IIb. Outbreaks from the subclades can have different characteristics. There is an outbreak of clade I mpox in Central and Eastern Africa, including the countries of Burundi, Central African Republic, Democratic Republic of the Congo, Republic of the Congo, Rwanda, and Uganda. Travel-associated cases on the African continent have been reported in Kenya, Zambia, and Zimbabwe. There have also been several travel-associated clade I mpox cases reported in other areas, including in Germany, India, Sweden, Thailand, and the United Kingdom.

Clinicians should be aware of mpox symptoms, ask patients with comparable signs and symptoms about recent travel history and other risk factors for mpox, and consider mpox testing. Given the widespread outbreaks in Central and Eastern Africa, additional travel-associated cases may be reported in the future in the United States. Suspected and confirmed cases of clade I mpox should be reported to local, territorial, and state public health authorities as soon as possible. CDC recommends vaccination to people who are eligible for mpox vaccine, including those who may have a recent mpox exposure. Mpox vaccine is now commercially available.

Please feel free to reach out to the Delaware County 24 hour Wellness Line for general inquiries or information via e-mail DelcoWellness@co.delaware.pa.us or telephone 484-276-2100.

For reporting disease concerns or outbreaks, you may also use DCHDinfectioncontrol@co.delaware.pa.us and/or fax 484-229-4980.