Medical Journal of Dr. D.Y. Patil Vidyapeeth

: 2022  |  Volume : 15  |  Issue : 4  |  Page : 457--459

Monkeypox: Revisit of the old threat and emerging imported cases

Beuy Joob1, Viroj Wiwanitkit2,  
1 Sanitation 1 Medical Academic Center, Bangkok, Thailand
2 Honorary Professor, Dr DY Patil University, Pune, Maharashtra, India

Correspondence Address:
Beuy Joob
Sanitation 1 Medical Academic Center, Bangkok

How to cite this article:
Joob B, Wiwanitkit V. Monkeypox: Revisit of the old threat and emerging imported cases.Med J DY Patil Vidyapeeth 2022;15:457-459

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Joob B, Wiwanitkit V. Monkeypox: Revisit of the old threat and emerging imported cases. Med J DY Patil Vidyapeeth [serial online] 2022 [cited 2022 Jul 2 ];15:457-459
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Pox is a severe infection that can result in an acute sickness with visible symptoms on the skin. Pox, smallpox, and chickenpox are the most well-known human pox illnesses. Emergent zoonotic pox infections, in addition to the well-known pox infections, have emerged as a fascinating new topic in infectious medicine.[1] Monkeypox is a zoonotic disease caused by an orthopoxvirus called the monkeypox virus (MPXV). Monkeypox has expanded to non-endemic areas, posing a serious public health threat.[2] Monkeypox is a rare pox infection that has returned, with zoonosis being suspected as the cause.[1] The virus that causes human monkeypox was very recently found.[3] The disease's endemic region is Africa. The main source of infection is going to a forest.[4] Human Monkeypox Virus (HMPV), a zoonotic disease, is endemic in the Congo basin and West Africa.[1] Its similarities to smallpox infection, increasing susceptibility to infection in human populations, lack of a definitive cure, and potential for use as a bioterrorism agent underline its public health importance.[1]

Monkeypox and varicella co-infection has also been documented.[5] Patients with human monkeypox infection often suffer acute disease, according to clinical characteristics. The chief signs of the sickness, according to Kalthan et al.,[6] were fever and rash. A novel diagnostic test kit to aid in the confirmation and identification of infections is now available.[7] The recent discovery of monkeypox infection transfer from person to person[8] has sparked great concern. Furthermore, there have been reports of resurrected monkeypox in many endemic places, which may be linked to the use of small pox vaccination, as well as numerous reports of imported cases in many new non-endemic settings.

What is monkeypox?

Monkeypox was initially discovered in 1958, when two outbreaks of a pox-like disease occurred in monkey study colonies. The first human case of monkeypox was detected in the Democratic Republic of Congo in 1970, during a period of heightened efforts to eradicate smallpox. Since then, human cases of monkeypox have been reported in various Central and Western African countries.[1] Monkeypox is a zoonotic illness caused by the monkeypox virus, which is an orthopoxvirus (MPXV). Monkeypox has spread to locations where it is not endemic, creating a severe public health danger.[2] Monkeypox is an uncommon pox infection that has resurfaced, and the cause is considered to be zoonosis.[1]

Monkeypox symptoms in people are similar to, but less severe than, smallpox symptoms. Fever, headache, muscle aches, and tiredness are among symptoms of monkeypox. The fundamental distinction between smallpox and monkeypox symptoms is that monkeypox causes lymph node swelling (lymphadenopathy), but smallpox does not. Monkeypox has a 1–2 week incubation period (from infection to symptoms), although it can be as short as 521 days. The disease lasts about 24 weeks on average. Monkeypox has been demonstrated to kill one out of every ten people who develop the disease in Africa.[1] The gold standard for diagnosis is now polymerase chain reaction (PCR) testing of samples from cutaneous lesions and blood.

The monkeypox virus is spread when a person comes into contact with it from an animal, a human, or contaminated materials. The virus enters the body through open wounds, the respiratory tract, or mucous membranes.[1],[5] Animal-to-human transmission can occur through bites or scratches, bush meat preparation, direct contact with bodily fluids or lesion material, or indirect contact with lesion material, such as through contaminated bedding.[1],[5] The principal mode of human-to-human transmission is thought to be large respiratory droplets. Because respiratory droplets can only travel a few feet, it is critical to maintain continuous face-to-face contact.[1],[5] Direct and indirect contact with body fluids or lesion material, such as through clothing, are both dangerous.[1],[5]

Revisited monkeypox

Monkeypox, a zoonotic disease caused by an orthopoxvirus, causes a smallpox-like illness in humans. Since the discovery of the first human cases of monkeypox in the Democratic Republic of the Congo (DRC) in 1970, the illness has spread to other parts of Africa (mostly West and Central), with cases outside of Africa surfacing in recent years.[9] Bunge et al. discovered an increase in monkeypox cases, especially in highly endemic locations, as well as a spread to neighboring countries and a shift in the median age from children to young adults. According to Bunge et al.,[9] these findings could be linked to the termination of smallpox immunization, which provided some cross-protection against monkeypox, resulting in increased human-to-human transmission. The substantial resurgence of monkeypox in Nigeria in 2017 appears to have been prompted by a combination of population growth, accumulation of unprotected cohorts, and a decline in smallpox vaccine protection.[10] The expanding unvaccinated population, according to Nguyen et al.,[10] means that entire families, not just children, are now more vulnerable to monkeypox, increasing the risk of human-to-human transmission. As seen by the monkeypox and buffalopox outbreaks, waning smallpox immunity may enhance the risk of animal-to-human transmission, followed by community transmission person-to-person and through contact with fomites.[11] The small pox vaccine could be reintroduced to assist combat the epidemic. The vaccination should be given to at least one disease contact individual.[11]

New emerging imported cases

The rise of epidemics outside of Africa, according to Bunge et al.,[9] emphasizes the disease's worldwide significance. For a better knowledge of the disease's ever-changing epidemiology, increased surveillance and case identification are critical methods. The medical community has been alerted by an increasing number of reported cases in several nations.[2],[12],[13] Between 2018 and2021, six unrelated Nigerians were diagnosed with monkeypox in non-African nations in the United States: four in the United Kingdom and one each in Israel and Singapore.[12] A guy travelling from Nigeria, to Texas in July 2021 became the sixth non-African to develop monkeypox.[12] Flying links were discovered to be responsible for up to 74% of all interactions.[12]

The patient was treated with tecovirimat, an antiviral drug used to treat orthopoxvirus infections, and his home was thoroughly decontaminated.[12] On March 2022, a case of monkeypox was discovered in a returning tourist from Nigeria to Maryland.[13] Costello advocated that public health systems be alerted of potential strategies to prevent the spread of monkeypox because of the global health implications.[13] Seven cases of monkeypox have been confirmed in Europe.[2] Instances of imported monkeypox in the United States and Europe suggest that the disease could return in other parts of the world.

Human-to-human transmission is now being monitored. An increasing number of reported cases in numerous nations have alerted the medical community. coronavirus disease 2019 (COVID-19) taught us that if an epidemic occurs, we must respond quickly, thoroughly assess the situation, and take necessary action. Despite the fact that monkeypox is an old disease, a new genetic mutation may have caused a more severe illness and a widespread outbreak. At this time, clinical investigation of newly emerging cases, including in-depth pathogen molecular analysis, disease control system implementation, including good case screening to avoid disease importation from endemic areas, and readiness for possible large-scale outbreak correspondence are all possible needs.

Roles of vaccination against monkeypox

The most effective disease control strategies, including the possibility of vaccination with new generation vaccines and treatment with recently developed antivirals, all require a better understanding of the genomic evolution and changing epidemiology of orthopox viruses, the utility of in-field genomic diagnostics, and the most effective disease control strategies.[14] As earlier noted, the wanning of small pox vaccination is associated with a change in epidemiology of monkeypox. Given the random and relatively unusual occurrence of the disease, as well as the potential for problems following vaccination with vaccinia, which protects against monkeypox, mass vaccination in at-risk locations is barely warranted at this time.[15] The particular vaccine against monkeypox is also accessible right now. The US Food and Drug Administration has licensed Imvamune or Imvanex as an attenuated live virus vaccination for the prevention of monkeypox.[15] New medicines and vaccinations offer hope for treating and preventing monkeypox, but more study is required before they can be used in an endemic situation.[16]


Monkeypox is an ancient viral disease that has been seen in Africa on occasion. Resurrected monkeypox arises as a new threat when normal small pox inoculation is discontinued in many regions. Furthermore, the recent influx of new cases into Europe and the United States highlights the significance of quick response in the event of a large-scale outbreak of this re-emerging virus. To better understand and prevent human infections, additional research on the virus's epidemiology, ecology, and biology is needed in endemic locations.

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Conflicts of interest

There are no conflicts of interest.


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