US boosts testing for new mpox strain, ensures vaccines at local pharmacies

The United States has beefed up testing and surveillance for a new strain of mpox and has ensured that vaccines are readily available at local pharmacies and community health centers, senior administration officials said in a briefing on Friday.

No cases of the more transmissible strain of the virus have been confirmed in the United States, but experts are preparing for that possibility following a World Health Organization declaration last month of a global public health emergency, the second such declaration in two years. The new strain, called clade Ib, has caused a major surge in cases in the Democratic Republic of Congo, which has spilled over to several neighboring countries.

Travel-related cases have been confirmed in both Sweden and Thailand. In a briefing on Friday, senior US administration officials said any American doctor can now order an mpox test, which can be processed through national laboratory chains. Positive tests that are not the older strain of mpox will be sent to the US Centers for Disease Control and Prevention for confirmation. Health officials in Wayne County, Michigan, last month had reported a new case of mpox, but additional testing showed that it was from the older strain known as clade II, a county health official told Reuters on Thursday.

Currently, the United States is continuing to see about three cases a day of mpox from the clade II virus that caused a public health emergency in 2022. Officials said they have been working to make mpox vaccines widely available through local pharmacies, noting that because Bavarian Nordic's Jynneos vaccine has been commercialized, it should be covered by most insurance plans.

Vaccines can also be obtained through public health departments and community health centers, irrespective of insurance status, to encourage vaccination among individuals who were most susceptible during the clade II outbreak in 2022: mostly men and bisexual men who have sex with men, officials said.

The US government also has added testing for any form of mpox to its wastewater surveillance system, and said there is good coverage in most major cities. The government is working to add clade I-specific testing.

The government has also been working on rapid tests, and while such efforts have been challenging, an official said the Rapid Acceleration of Diagnostics (RADx) Tech program that spurred production of COVID-19 tests has developed such a test, which could be available in the coming months. Mpox, which typically causes flu-like symptoms and pus-filled lesions but can be deadly, spreads through close contact, including through sex.