CDC Ramps Up Testing, Boosts Monkeypox Vaccination Supply

The Centers for Disease Control and Prevention (CDC) has expanded access to vaccines, tests, and treatments for monkeypox, agency officials said in a webinar Tuesday.

The CDC expects to release more than 750,000 doses of the JYNNEOS vaccine from its strategic stockpile within days, said panelists at the Clinician Outreach and Communication Activity (COCA) call.

In addition, by working with commercial labs, the agency has expanded US testing capacity and streamlined requirements for administering the antiviral tecovirimat, they said.

“We must work together to educate and protect those at greatest risk, leading with education and not stigmatization,” said Jennifer McQuiston, DVM, MS, incident manager for the agency’s monkeypox response. “And we need you, our frontline health care providers and public health practitioners, who are critical to get the outbreak under control.”

Monkeypox, which is closely related to smallpox, spreads through close physical contact and typically causes flu-like symptoms and pus-filled skin lesions. It is endemic to parts of West and Central Africa, but has recently spread to at least 66 countries where it was not previously identified, with 15,000 cases reported in these countries since April of this year, mostly among men who have sex with men.

The World Health Organization on Saturday declared the monkeypox outbreak a global health emergency, its highest level of alert.

Reported cases of monkeypox have been increasing exponentially since the spring in the United States, with 3487 cases reported in 45 states, the District of Columbia, and Puerto Rico, said María E. Negrón Sureda, DVM, PhD, MS, the CDC monkeypox Epidemiology Task Force Lead.

The median age of people infected is 35 years, with 98.4% of cases attributed to male-to-male sexual contact. Ninety-nine percent of cases include rash, 70% malaise, 64% fever, and 63% lymphadenopathy.

The CDC has beefed up testing capacity by enlisting five commercial laboratories to process 70,000 tests in addition to the 10,000 tests the US Laboratory Response Network (LRN) is processing per week, said Christina Hutson PhD, MS, Laboratory and Testing Task Force Lead.

“We have had significant success in expanding diagnostic testing for monkeypox to these commercial laboratories that have national reach and can perform tests ordered from anywhere in the country,” she said.

The LRN labs perform the US Food and Drug Administration (FDA)-cleared nonvariola orthopoxvirus-specific PCR test, sending samples to the CDC for sequencing. And four commercial laboratories are each doing 10,000 tests per week the same way. The fourth commercial lab, Quest Diagnostics, is processing an additional 30,000 of its own monkeypox tests per week, Hutson said.

The labs all accept lesion material swabbed from any part of the body as testing specimens. But clinicians should check with the specific lab about whether the labs take dry swabs or swabs in transport media. It isn’t necessary to lance or deroof the lesions, just swab vigorously, Hutson said.

She advised clinicians to take epidemiological criteria as well as clinical presentation into consideration in deciding whether to test.

Each commercial lab may have its own CPT billing code for monkeypox, and will bill private insurers, Medicaid, or Medicare. The government is looking for money to pay for tests for uninsured people, Hutson said.

Patients who test positive can be treated with tecovirimat, an antiviral developed for smallpox, said Yon Yu, PharmD, Regulatory Affairs and Clinical Guidelines Team Lead. The drug has been tested against monkeypox only in animals, but it can be prescribed to humans under an expanded access investigational new drug authorization. State and territorial health departments can provide information about where to get the drug, as can the CDC through its Emergency Operation Center at 770-488-7100 or at poxvirus@cdc.gov.

The CDC has updated its protocol for providing tecovirimat. Patient visits can be conducted through telemedicine, laboratory testing is optional, and no preregistration is required for clinicians and healthcare facilities to prescribe it.

Clinicians do need to obtain informed consent, conduct a baseline assessment, and complete a patient intake form. They should document progress once during and once after treatment on the clinical outcome form, and report any serious adverse events, Yu said. The CDC has set up a webpage specifically for tecovirimat guidelines.

In addition to tecovirimat, the FDA has licensed two vaccines, JYNNEOS (Imvamune or Imvanex) and ACAM2000, for monkeypox.

The CDC recommends vaccination within 4 days for people who have a high degree of exposure, but not for those with “brief interactions and those conducted using appropriate PPE [personal protective equipment].” Further details are available on the CDC webpage for monkeypox vaccination.

Not enough JYNNEOS is available to meet the demand. Over 100 million doses of ACAM2000 are available, according to the CDC, but this vaccine comes with a greater risk for adverse reactions and the agency advises against using it in people with some health conditions, including a weakened immune system, skin conditions like atopic dermatitis/eczema, or pregnancy.

In addition, ACAM2000 is made from a live virus, which grows at the site of the inoculation lesion and can spread to other parts of the body or infect other people, making precautions necessary.

Given the limited supply of JYNNEOS, the CDC recommends prioritizing it for people who are at risk for adverse events with ACAM2000 or severe disease from monkeypox, such as those with HIV or immunocompromising conditions, said Steve Flores, PhD, Vaccine Team Colead.

The CDC has ramped up its distribution of JYNNEOS, from 56,000 doses June 28, 2022, to 240,000 July 15, 2022, he said. It anticipates reaching more than 750,000 doses in a matter of days, with an ultimate target of 1.9 million for 2022 and another 2.2 million in the first half of 2023.

“We do not know if JYNNEOS will fully protect against monkeypox virus infections in the context of this current outbreak,” he cautioned. “So it is important that individuals take additional prevention measures, and self-isolate as soon as they develop symptoms such as rash. Infections despite vaccination may still occur.”