Emerging Poxvirus Diseases: A look at Lumpy Skin Disease, Monkeypox and More

Pashu Sandesh, 25 October 2023

Dr. Ragini Mishra

Ph.D. Scholar- Division of Veterinary Microbiology, ICAR-IVRI, Izatnagar-243122, Bareilly

Poxviruses are a family of double-stranded DNA viruses that can cause a variety of diseases in humans and animals. While smallpox, caused by the variola virus, is the most well-known poxvirus disease, there have been emerging or reemerging poxvirus infections in recent years. Here is some information regarding a few emerging poxvirus diseases:

1. Lumpy skin disease virus: Lumpy skin disease (LSD) is an emerging poxivirus that primarily affects cattle. It is caused by the lumpy skin disease virus (LSDV), which is a member of the Capripoxvirus genus. The disease is characterized by the development of nodules or lumps on the skin, mucous membranes, and internal organs of cattle. Previously it was confined to certain regions of Africa, but it has emerged as a significant concern in recent years. It has spread to various countries in Africa, the Middle East, Europe, and Asia. The disease is primarily transmitted through arthropod vectors such as biting flies (e.g., mosquitoes and ticks). Direct contact with infected cattle or contaminated equipment can also contribute to the spread of the virus. In addition to the characteristic skin nodules, infected cattle may exhibit fever, nasal discharge, ocular discharge, and lameness. The severity of clinical signs can vary. Vaccination is a key strategy for preventing lumpy skin disease. Several vaccines have been developed and are used in affected regions. 
2. Monkeypox: Monkeypox is a viral disease that was first identified in monkeys in 1958 and later found to infect humans. It is caused by the monkeypox virus, which belongs to the Orthopoxvirus genus. Monkeypox is endemic in parts of Central and West Africa. The symptoms of monkeypox in humans are similar to those of smallpox, but generally milder. Human-to-human transmission is possible, although it is limited. Monkeypox outbreaks have occurred sporadically, with the most recent outbreaks reported in several African countries and the United Kingdom.
3. Cowpox: Cowpox is a viral disease primarily affecting cows and other animals, but it can also infect humans. It is caused by the cowpox virus, a member of the Orthopoxvirus genus. Humans usually acquire the infection through direct contact with infected animals or contaminated materials. The disease is generally mild in humans, with localized skin lesions and flu-like symptoms. Cowpox has been reported in various countries, including the United Kingdom and Germany.
4. Vaccinia Virus Infections: Vaccinia virus is closely related to the variola virus, which causes smallpox. Vaccinia virus was historically used as the active component in the smallpox vaccine. However, cases of adverse reactions and localized infections associated with vaccination have been reported. More recently, cases of vaccinia virus infections have been documented in inpiduals without a vaccination history. These infections can occur through occupational exposure, contact with animals, or through the handling of contaminated materials.
5. Other Poxvirus Infections: In addition to the above-mentioned, there have been reports of other emerging poxvirus infections in recent years. For example, Orf virus infection, also known as contagious ecthyma, is caused by a parapoxvirus that primarily affects sheep and goats but can also infect humans. Other lesser-known poxviruses, such as the Yaba-like disease virus and the tanapox virus, have also been associated with sporadic human infections.

It's important to note that while these emerging poxvirus diseases have been reported, they generally occur in localized outbreaks and are not widespread public health concerns. However, ongoing surveillance and research are important to monitor these viruses and understand their potential for further spread or evolution.