- Department of General Surgery, All India Institute of Medical Sciences, Patna, Bihar, India
- Department of Neurosurgery, All India Institute of Medical Sciences, Patna, Bihar, India
- Department of Microbiology, ESIC Hospital, Patna, Bihar, India.
Saraj Kumar Singh, Department of Neurosurgery, All India Institute of Medical Sciences, Patna, Bihar, India.
DOI:10.25259/SNI_1176_2022Copyright: © 2023 Surgical Neurology International This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.
How to cite this article: Atul Anand1, Anand Kumar Das2, Sona Bhardwaj3, Saraj Kumar Singh2. A brief review of the monkeypox virus and emerging concerns for neuroinvasiveness. 03-Mar-2023;14:78
How to cite this URL: Atul Anand1, Anand Kumar Das2, Sona Bhardwaj3, Saraj Kumar Singh2. A brief review of the monkeypox virus and emerging concerns for neuroinvasiveness. 03-Mar-2023;14:78. Available from: https://surgicalneurologyint.com/surgicalint-articles/12180/
Background: Amidst the ongoing COVID-19 pandemic, monkeypox virus (MPXV) disease has been recognized as another disease of pandemic nature by the World Health Organization. Nearly four decades after the eradication of smallpox, as half of the world population is naïve to ortho-pox viruses (supposedly due to lack of immunity by vaccination), MPXV remains the most pathogenic species of the family of poxviruses.
Methods: The articles on MPXV were searched on PubMed/Medline and data were retrieved and analyzed.
Results: Although reported as a disease of milder exanthem and lower mortality as compared to smallpox, the MPXV disease tends to be neuroinvasive. This article highlights the neurological signs and symptoms of MPXV disease and discusses, in brief, the management strategies.
Conclusion: Neuroinvasive properties of the virus as demonstrated in in vitro studies, and further verified by neurological illnesses in patients, present a special threat to mankind. Clinicians must be prepared to recognize and treat these neurological complications and start treatment to limit long-lasting brain injury as seen in patients with COVID-19.
Keywords: Central nervous system, Monkeypox virus, Neurological, Pathogenesis
Viruses are important contributors to the World Health Organization’s (WHOs) current list of priority diseases. Crimean-Congo hemorrhagic fever, Marburg virus disease, Middle East respiratory syndrome coronavirus, severe acute respiratory syndrome, Ebola virus disease, Lassa fever, Nipah virus diseases, Zika virus disease, Rift Valley fever, and the novel coronavirus (COVID-19) are currently included in the list.[
TAXONOMY AND EPIDEMIOLOGY
MPXV is a double-stranded enveloped DNA virus of the family Poxviridae, subfamily Chordopoxvirinae, and genus Orthopoxvirus.[
PATHOGENESIS WITH NEUROINVASIVE POTENTIAL
Monkeypox is a vesicopustular illness with a secondary attack rate of around 10% in those who have not received the smallpox vaccine.[
CLINICAL FEATURES WITH NEUROLOGICAL MANIFESTATIONS
On inoculation, a febrile prodromal phase follows with an incubation period of 7–17 days. This phase manifests as fever, headache, malaise, myalgia, and lymphadenopathy, and lasts for about 1–4 days. The febrile phase is followed by a rash period lasting about 14–28 days, characterized by centrifugally distributed painful and pruritic rashes, which evolve from maculopapular to vesicopustular.[
Mortality is uncommon-the case fatality rate varies from 1% to 11%.[
Neurological manifestations range from non-specific symptoms such as headache, myalgia, fatigue, and photophobia to severe complications such as seizures and encephalitis. The WHO data report headache as one of the symptoms in about 30% of patients [
Bar diagram showing proportion of symptoms in monkeypox illness (see Table 1 for details). Adapted from: 2022 Monkeypox Outbreak: Global Trends [Internet]. [Cited 2022 Dec 19]; Available from:
As evident in the UK Health Security Agency case definition of probable monkeypox infection,[
In the absence of a clinically approved anti-viral agent, prevention remains the key. Behavioral risk-reduction strategies include avoidance of close contact with anyone suspected to have Monkeypox infection. This may be accomplished by home-based or hospital-based isolation. Airborne and contact precautions, including hand-hygiene practices as learned from the COVID-19 pandemic, are encouraged among healthcare workers. Considering the recent outbreaks, MSM should be cautious.
Symptomatic cases usually have a mild self-limiting illness, and the treatment is supportive focusing on analgesia, hydration, and nutrition. Acetaminophen, non-steroidal anti-inflammatory agents, and topical antihistamines are used when required.[
Chemotherapeutic agents at various stages of trial against the MPXV include NIOCH-14, Cidofovir, and CMX-001.[
The recent outbreaks of the MPXV may be attributed to the encroachment of human civilization into areas with zoonotic reservoirs in the setting of waning immunity against the smallpox virus. MPXV disease is a systemic illness with its effect on most organ systems unknown. Neuroinvasive properties of the virus as demonstrated in in vitro studies, and further verified by neurological illnesses in patients, present a special threat to mankind. Clinicians must be prepared to recognize and treat these neurological complications and start treatment to limit long-lasting brain injury as seen in patients with COVID-19. Lessons learned from the COVID-19 pandemic, especially the isolation and hand-hygiene practices hold true for protection against the MPXV and other potential pandemics given the emerging list of pathogens that cause human disease.
Saraj Kumar Singh contributed to the study conception. Material preparation and data collection were performed by Atul Anand, Anand Kumar Das and Sona Bhardwaj. The first draft of the manuscript was written by Atul Anand and Anand Kumar Das and all authors commented on previous versions of the manuscript. The first two authors have contributed equally in the preparation of the manuscript. All authors read and approved the final manuscript.
Declaration of patient consent
Patient’s consent not required as there are no patients in this study.
Financial support and sponsorship
Publication of this article was made possible by the James I. and Carolyn R. Ausman Educational Foundation.
Conflicts of interest
There are no conflicts of interest.
The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Journal or its management. The information contained in this article should not be considered to be medical advice; patients should consult their own physicians for advice as to their specific medical needs.
We acknowledge our digital artist Chandan Kumar for preparing the schematic representation.
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