In mid-September 2023, an elderly resident of the Kenai Peninsula, south of Anchorage, Alaska, who was undergoing cancer treatment and suffered from immunosuppression, noticed a painful red papule in his right armpit. Naturally, the shock was terrible, and he decided to immediately consult a doctor. Over the next six weeks, he visited the primary health care center and the local emergency department several times for clinical evaluation of the injury.
The case was confusing and possible contamination was difficult to determine. The elderly man did not respond to antibiotic treatment. A needle biopsy revealed no evidence of malignancy or bacterial infection. Medical workers were confused. Over time, the patient felt fatigue and increasing induration. The pain in my right armpit and right shoulder was getting worse.
On November 17, the prognosis worsened and he was hospitalized. The underlying cause was extensive progression of suspected infectious cellulitis, which affected the range of motion of his right arm. There was no time to lose, and the patient was transferred to Anchorage and transferred to a hospital with more resources and resources.
In Anchorage, a patient complained of severe burning pain of a neuropathic type. The biopsy site in the right axilla was not healing and was oozing copious serous fluid. There was extensive muscle inflammation affecting the right armpit and shoulder muscles. Four small pox-like lesions were also found in diffuse locations throughout the body. What’s happened?
After an extensive battery of laboratory tests, a sample sent to the Centers for Disease Control and Prevention (CDC) tested positive for Alaska smallpox virus (AKPV). That is, an orthopoxvirus discovered in 2015 in Alaska, in the Fairbanks area, of which only seven cases of human infection had been reported until that time. All of them were observed in residents of the Fairbanks area and were accompanied by mild, spontaneous illnesses consisting of localized rash and lymphadenopathy.
After the possible pathogen was identified, the elderly man became the eighth case of AKPV infection and received specific treatment, which consisted of intravenous tecovirimate, intravenous immunoglobulin, and oral brincidofovir. After a week of therapy, the patient’s condition began to improve. Unfortunately, this was not enough. Despite intensive medical care, after some time the patient developed delayed wound healing, malnutrition, acute renal failure and respiratory failure. He died at the end of January 2024. In the second week of February 2024, health department officials confirmed that the death was due to the Alaska smallpox virus.
Its reservoir can be shrews and voles.
There are currently more than 10,000 types of viruses described, and we know that about 270 of them infect humans. Some of these viruses have been known for centuries, others have emerged recently. In fact, viruses account for about two-thirds of all new human pathogens. These new viruses vary greatly in importance, from the rare and mild disease caused by the Menangle virus to the devastating public health impact caused by the coronavirus SARS-CoV-2.
Of the viruses known to infect humans, about 80% occur naturally in non-human reservoirs, primarily in mammals and birds and, to a lesser extent, in arthropods and other wild animals. Zoonotic infectious agents, that is, those that are transmitted from animals to humans, are estimated to account for about 60% of known human pathogens and up to 75% of emerging human pathogens. Unfortunately, there is insufficient knowledge about wild animals, which can harbor thousands of unknown virus species, and this is a serious disadvantage since many of them can be pathogenic to humans.
Evidence to date indicates that Alaska poxvirus is present in several species of small mammals, most notably shrews and red-backed voles.Kletriomys rutilus), which can act as a reservoir. Thus, we are faced with a new zoonosis. Although available evidence suggests that the public health impact of Alaska poxvirus is limited, it is likely to be widespread among small mammal populations in Alaska, and other infections may have occurred in humans but have not been diagnosed.
In addition to Alaska smallpox virus, several other orthopoxviruses that have been recently described, such as Achmeta virus or Abatino virus, indicate the possibility of unknown members of this genus with zoonotic potential.
There are currently no human-to-human transmissions of the Alaska smallpox virus. However, because some orthopoxviruses can be transmitted through direct contact with skin lesions, people with wounds that may have been caused by Alaska smallpox are advised to cover the affected area with a bandage.
Poxviruses infect a wide range of hosts, including insects, birds, reptiles and mammals.
Among the poxviruses, the genus Orthopoxvirus includes several viruses of medical importance, including variola virus (VARV), the causative agent of human smallpox, and vaccinia virus (VACV), which was used in the smallpox eradication campaign.
Monkeypox family
Other orthopoxviruses with zoonotic potential, such as MPox virus (commonly known as monkeypox virus) and vaccinia virus, are increasingly becoming causes of human disease. In fact, the mpox outbreak, which emerged in May 2022 and is still ongoing, has caused more than 93,000 cases and 177 deaths. The discontinuation of routine vaccination against eradicated human smallpox may have contributed to this situation, as this vaccine induced a degree of immunity in the population against other orthopoxviruses.
In addition to those mentioned, there are many other pathogenic mammalian orthopoxviruses. Examples include, but are not limited to, ectromelia mousepox virus, camelpox virus, raccoonpox virus, gerbilpox virus, cowpox virus, skunkpox virus, or certain sublineages of the cowpox virus such as rabbitpox virus and buffalopox virus.
The wide host range, wide geographic distribution, and continued global emergence of zoonotic viruses, including emerging orthopoxviruses, pose a global health threat that requires close surveillance and appropriate preventive measures.
In this situation, the most sensible thing to do is to take an urgent approach One health and recognize that we cannot care for human health without also caring for the health of animals and the environment.