Dear Editor
The monkeypox virus belongs to the orthopoxvirus that is genetically different from the others members of the poxviridae family. Monkeypox was first reported in a monkey in 1958 and hence got the name. The virus was found to be zoonotic in 1970 when a small child acquired the infection in the Democratic Republic of the Congo [1]. On 17 August 2022 the World Health Organization (WHO) reported that the incidence of monkeypox infection continue to rise globally, with more than 35,000 cases across 92 countries and territories including 12 deaths (https://news.un.org/en/story/2022/08/1124892). The majority of cases are being reported from United states and Europe, and mostly among men who have sex with men. Surprisingly, the recent outbreaks in the United States, the United Kingdom, Italy, Belgium, Spain, Portugal, Sweden, Netherlands, France, Canada, Australia, and Germany does not follow the pattern of spread observed in the previous outbreaks outside of Africa, almost all of which have been linked with immigration or movement of people from Africa or exposure to infected exotic pets [2]. So far, 98% of cases occurred outside of Africa where the virus is endemic. This atypical outbreak of monkeypox raised the concern of global researchers and health agencies to contain it at the earliest (Fig. 1 ). Subsequently, WHO declared the monkeypox virus as Public Health Emergency of International Concern (PHEIC).
Fig. 1.
Epidemiology of monkeypox. The figure was created with BioRender.com.
The virus has a wide range of hosts and many animal species may become infected with monkeypox virus under natural conditions, including squirrels, non-human primates, and rats. Earlier investigation of the 2003 outbreak of monkeypox in USA identified an international shipment of about 800 small mammals from Ghana to Texas as the probable source for the introduction of monkeypox virus into the USA. These mammals were of six genera of African rodents: rope squirrels (Funisciurus spp), tree squirrels (Heliosciurus spp), Gambian giant rats (Cricetomys spp), brushtail porcupines (Atherurus spp), dormice (Graphiurus spp), and striped mice (Hybomys spp) [3]. The virus was imported in 2003 into the United States of America via Gambia rats, wild squirrels (all African species), and infected prairie dogs, then crossed the species barrier to humans. Human to human transmission of the virus mainly occurs through close contact with the lesions, body fluids, contaminated clothing and bedding, and respiratory droplets from infected people (Fig. 2 ). The current outbreak is mainly occurring in men who have sex with men, and has been associated with unexpected anal and genital lesions. In this context the possibility of sexual transmission of the virus needs to be thoroughly investigated.
Fig. 2.
Transmission, Clinical signs and Containment strategies of monkeypox. The figure was created with BioRender.com.
Poxviruses infect almost all domestic animals but till today no poxvirus infecting domestic cats and dogs have been reported. Recently, the first case of monkeypox virus infection in dogs has been reported that might have been transmitted from infected human being [4]. The male Italian greyhound dog, aged 4 years, presented to the clinics with pox like lesions, including abdomen pustules and a thin anal ulceration. Skin scrapings and swabs of the anus and oral cavity of the dog were tested positive for monkeypox virus by PCR. Sequence analysis of this isolated monkeypox virus confirmed the isolated virus to be of hMPXV-1 clade, lineage B.1, which has been spreading in nonendemic countries since April 2022. In the current episode of monkeypox virus outbreak, the virus has crossed the species barrier to cause infection in dogs. In this context, the possibility of further spillover of the virus to new animal species cannot be overlooked. However, care should be taken to isolate the pets and wild animals kept in zoos, circuses and sanctuaries from human beings infected with monkeypox virus.
The jumping of species barrier by the monkeypox virus is an alarming situation for veterinary professionals and researchers. During recent decades, cowpox virus infections have been reported to reemerged in domestic cats and other animals, including wild animals in captivity [5,6], and have increased in humans subsequent to transmission from rodents, cats, zoo and circus animals [7,8]. Since, the monkeypox virus is also crossing the species barriers like cowpoxvirus and other orthopoxviruses, the host range of this virus must be investigated, and further monitoring of monkeypox virus in domestic and wild animals is crucial. Strict surveillance of the virus among domestic felines and canines is utmost necessary to contain the virus. In addition, strict healthcare monitoring of domestic and wild animals, isolation of pets from infected human beings, proper healthcare monitoring of zoo attendees and implementation of recommended healthcare guidelines in zoos and circuses are the key to control further spillover of the virus. Furthermore, there is a wide scope for researchers to confirm secondary transmission of virus through pets and wild animals.
Ethical approval
Not Applicable.
Source of funding
No.
Author contribution
Nikhil K. C.: Conceptualization, Writing - review & editing. Jigyasa Rana: Writing - review & editing. Shailesh Kumar Patel: Conceptualization, Writing - review & editing. Aditya Agrawal: Writing - review & editing. Kumar Govil: Writing - review & editing. Alok Singh: Writing - review & editing. Megha Katare Pandey: Writing - review & editing. Dhruv Nitinkumar Desai: Writing - review & editing. Sita Prasad Tiwari: Writing - review & editing.
Trail registry number
Not Applicable.
Guarantor
Dr Shailesh Kumar Patel.
Provenance and peer review
Not commissioned, internally peer-reviewed.
Data statement
Data sharing is not applicable to this article as no new data were created or analysed in this study.
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
References
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