By Donna Campisano, specialist, Communications, APHL
When it comes to detecting an infectious disease and launching an effective public health response, quick action is everything. And New Hampshire’s response to a recent clade I mpox case—the third in the nation—was nothing if not quick.
Clade I mpox is a particularly severe and deadly form of the mpox virus. (There are two clades, or subtypes, of mpox—clade I and clade II; both are currently endemic in parts of Africa.)
Since November 2024, four cases of clade I mpox have been reported in four different states—California, Georgia, New Hampshire and New York. None are thought to be related, and all can be traced back to travel within Africa.
Here, a step-by-step timeline of how the New Hampshire case unfolded.
In February, a New Hampshire resident sought medical care at several area emergency rooms for flu-like symptoms.
When an attending physician and infectious disease specialist at one of the hospitals noticed lesions on the person’s skin and asked about recent travel history (the person had recently been to Eastern Africa), mpox was suspected and swab samples of the lesions were taken.
The specimens were packaged in viral transport media and couriered to the state’s Bureau of Infectious Disease Control the same day. The bureau is part of the nation’s Laboratory Response Network (LRN), which is a network of laboratories that can respond to biological and chemical threats as well as other public health emergencies.
Using a US Centers for Disease Control (CDC) developed non-variola orthopoxvirus (NVO) test, the specimens were analyzed and a presumptive positive result for a pox virus was returned within four hours.
“Still, we needed to get confirmation this was mpox and a determination on what clade it was,” said Rebecca Lovell, a microbiologist IV at New Hampshire Public Health Laboratories who worked on the case. “Our lab is a Tier 2 laboratory; pox confirmation needed to come from a Tier 1 lab or CDC.”
Knowing that a quick turnaround in testing is vital to a patient starting treatment and public health officials containing any potential outbreak, Lovell and her colleagues took the steps necessary to get quick confirmation of the test results.
In New Hampshire’s case, presumptive positive pox virus tests are sent to CDC—but first, CDC needed to issue authorization for the specimens to be sent.
Given the cuts in federal funding and government workforce, Lovell was worried how quickly CDC would respond. “But I reached out to my counterparts there asking them to give this test priority, and CDC responded very quickly,” she said. “Within 24 hours of them getting the specimens, they came back with a confirmed positive for clade I mpox. From our initial testing to CDC’s confirmation, just 72 hours passed. Honestly, if CDC had not responded so quickly, I’m not sure what would have happened.”
Once mpox was suspected, the patient was isolated and monitored. When results came back positive for clade I, the patient was treated and the state’s epidemiologists conducted contact tracing while also issuing a health alert to healthcare providers.
The patient is now doing well and out of isolation; contacts were isolated and monitored and no other clade I mpox cases have been reported in New Hampshire.
“We had plenty of mpox testing capability,” Lovell said. “We had the tests, the reagents and the personal protective equipment. We had some JYNNEOS vaccine (a vaccine used for mpox and smallpox) on hand and got more from federal sources in case they were needed. Being a member of the LRN, we were prepared.”
But without a strong investment in public health, that may not always be the case.
CDC says the risk of clade 1 mpox to the general population is low, but the virus has now touched down on both shores and in places in between. Cases are all travel related, and while infections may have not originated here, they’re only a plane ride away.
Consider the case of clade II mpox—a milder form of mpox rampant in Western Africa. The virus wasn’t seen in this country until 2022, when the first case was detected by the Massachusetts Department of Health’s State Public Health Laboratory Services, a member of the LRN. But cases quickly mounted that summer when the seven-day national average was more than 450 cases a day; in 2024, more than 3,000 cases in the US were reported. The virus is still circulating, but thanks to a strong public health response, numbers are low. As the New Hampshire case underscores, building and maintaining strong public health systems—including supporting CDC programs and LRN deployment capabilities—are essential to stopping diseases, wherever they take root. Only when investments in public health are robust can disease be contained and lives be saved.
