Monkeypox information for health care providers

What providers need to know about monkeypox clinical guidance and smallpox/monkeypox vaccine (JYNNEOS™) administration, eligibility, and availability in Massachusetts.

Table of Contents

Clinical guidance


JYNNEOS vaccine administration

The JYNNEOS vaccine is shipped in 100 boxes of 20 doses each, in single-dose vials.

Vaccine is supplied to providers thawed and must be refrigerated at 2-8 degrees C for up to 8 weeks based on information provided by the manufacturer.

On August 9, CDC and FDA released an EUA (Emergency Use Authorization) allowing an alternative dose vaccination regimen in people 18 years and over and allowing the use of the JYNNEOS vaccine in individuals younger than 18 years.

The original JYNNEOS approval included the use of two 0.5 mL doses administered subcutaneously (under the skin). The alternative regimen allows the use of two lower doses, 0.1 mL of vaccine administered intradermally (into the skin.  Providers administering JYNNEOS vaccine will begin utilizing this alternative dose vaccination regimen beginning August 18, 2022.


Vaccination will be available to individuals who live or work in Massachusetts and meet the CDC’s current eligibility criteria, prioritizing those who are most at risk of exposure to an individual with monkeypox. This includes:

  • Known contacts identified by public health via case investigation, contact tracing, and risk exposure assessments (this may include sexual partners, household contacts, and healthcare workers); as well as
  • Presumed contacts who meet the following criteria:
    • Know that a sexual partner in the past 14 days was diagnosed with monkeypox
    • Had multiple sexual partners in the past 14 days in a jurisdiction with known monkeypox

While many of the identified cases are within networks of self-identified gay and bisexual men, other men who have sex with men, and transgender individuals who have sex with men, people of any sexual orientation or gender identity can become infected and spread monkeypox.


Administration of JYNNEOS will be by appointment only. Healthcare providers will be responsible for performing risk and exposure assessment prior to vaccination. 

For a list of monkeypox vaccine providers and appointment information, visit How to obtain vaccine.


Please note that CDC has also made available the live replicating smallpox vaccine ACAM2000. This vaccine is available in larger quantities but has a number of characteristics that make it unsuitable for use in the current context, including considerably greater risk to the recipient compared with JYNNEOS. Local health departments and providers are not currently requesting ACAM2000.