番茄社区

In late January, a man living in Southcentral Alaska died after a severe infection from a rare infectious disease: Alaskapox.

Though earlier cases of Alaskapox had been identified in the Fairbanks region of the state starting in 2015, this was the first death. , the genome sequence was distinct from the Fairbanks cases and identified in the Kenai Peninsula where the man lived, over 300 miles away.

State and CDC officials said that although public and medical professionals should be aware of Alaskapox virus and how it is spread, those outside Alaska have no immediate cause for concern.

"There is not a reason for those outside of the state of Alaska to be concerned, based on the available evidence for acquiring Alaskapox virus infection," Julia Rogers, PhD, MPH, a CDC Epidemic Intelligence Service officer assigned to the Alaska Division of Public Health, told 番茄社区. "But rather just awareness that it does exist and we do know that it exists now in more than one region of the state."

What Happened in the Most Recent Alaskapox Case?

In mid-September of last year, an older man living in the Kenai Peninsula noticed a red lesion in his right axilla and visited his primary care practitioner and the local emergency department several times.

The man was immunosuppressed from cancer treatment, and had been caring for a stray cat that had scratched him several times, including near where the lesion developed. He had fatigue and increasing pain, followed by presumed infectious cellulitis, but a biopsy showed no malignancy or bacterial infection.

The man reported burning neuropathic-type pain. His biopsy site was not healing, and was draining fluid and surrounded by gray coalescent plaque. Four smaller lesions were noted in other locations on his body. Treatment with intravenous and oral antibiotics (intravenous tecovirimat [Tpoxx], intravenous vaccinia immunoglobulin, and oral brincidofovir [Tembexa]) seemed to improve his condition.

However, according to a February 9 bulletin from the , "despite intensive medical support in a long-term care setting, he later exhibited delayed wound healing, malnutrition, acute renal failure, and respiratory failure," followed by death.

What Is Alaskapox?

Alaskapox is an orthopox virus, in the same genus as smallpox, cowpox, and mpox. Genetically, Alaskapox with "old world" orthopox viruses (which include mpox and camelpox), as opposed to "new world" orthopox viruses.

Alaskapox was first discovered in 2015 in a patient from Fairbanks, Alaska. Six more human cases have been identified since.

Symptoms include lesions that some patients have mistaken for spider bites, accompanied by joint or muscle pain and swollen lymph nodes. According to the , "nearly all patients had mild illnesses that resolved on their own after a few weeks."

Joe McLaughlin, MD, MPH, chief of the Alaska Section of Epidemiology, told 番茄社区 that the most recent case was atypical. It "involved an immunocompromised patient and this one ... was the first case that we've identified of severe Alaskapox virus infection," he said.

Although state officials found the genome sequence in this patient's case to be phylogenetically distinct from the Fairbanks cases, the severity is likely unrelated.

"We would expect some genetic variation from region to region ... so that would be my first hypothesis, that what we're seeing here is a genetic variation of the virus in Alaska, which is geographically very large," McLaughlin said.

How Is Alaskapox Spread?

Experts believe Alaskapox is zoonotic and occurs in small mammals, which may spread to humans through domesticated animals. The Alaska Division of Public Health, the University of Alaska Museum of the North, and the CDC captured and sampled 176 mammals across the state in 2020 and found Alaskapox DNA in 12 red-backed voles and one shrew.

In the seven Alaska cases starting in 2015, McLaughlin said, patients had domestic pets or exposure to them. "The theory is that it might be possible for, for example, a stray cat out hunting small rodents to come into the household and directly inoculate somebody through a scratch," he explained. In the most recent case, the man occasionally let a stray cat into his home to care for it, though antibody and orthopox tests from the cat were negative.

So far, according to CDC and state officials, there is no evidence for person-to-person transmission, though the advises, "since certain orthopox viruses can be transmitted through direct contact with skin lesions, we recommend that people with skin lesions possibly caused by Alaskapox keep the affected area covered with a bandage."

The CDC has noted that climate change may contribute to the spread of Alaskapox. "Warming temperatures in Alaska have led to increases in vole populations, which can spread diseases like Alaskapox to humans," according to one . However, McLaughlin said there's still not enough known about the virus to predict a rise in infection due to climate change.

What Should Patients and Clinicians Do About Alaskapox?

McLaughlin said clinicians in Alaska should be aware of and educate patients about potential routes of transmission.

Rogers added that patients with symptoms similar to previous cases should see a healthcare professional, who can then report it directly to the Alaska Section of Epidemiology for confirmation.

"Hopefully based on increased awareness, we will be able to identify cases as they arise and be able to refer individuals to appropriate testing and antibiotic treatment for those that need it," she added.

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