Scientists from the UK have recently conducted a systematic review and meta-analysis to assess the types and prevalence of neurological and psychiatric symptoms associated with monkeypox virus infection in humans. They have identified a range of neurological symptoms with mild to severe intensities. The study is currently available on the medRxiv* preprint server.
The most common symptoms of monkeypox infection in humans include fever and skin rashes. However, neurological and psychiatric symptoms might also be present because the virus belongs to the same family of viruses as smallpox and smallpox infection is associated with a range of neurological manifestations, including encephalitis, seizures, and stroke.
In the current systematic review and meta-analysis, the scientists have outlined the range of neurological and psychiatric symptoms associated with monkeypox infection in humans. In addition, they have determined the prevalence of these symptoms.
Study design
A total of 1,702 studies investigating neurological and psychiatric symptoms in monkeypox-infected humans were selected for the study. Of these studies, 19 met the final eligibility criteria and were included in the systematic review. The total number of participants in these studies was 1,512.
Studies conducted on more than ten individuals, and symptoms reported in at least two separate studies were included in the meta-analysis. This led to the inclusion of six clinical symptoms in the meta-analysis, including myalgia, headache, fatigue, seizure, confusion, and encephalitis.
Important observations
The majority of studies included in the review were from the USA, followed by Nigeria, the Democratic Republic of Congo, the Republic of Congo, and the UK. Most of the studies were cohort studies and case series without controlled populations.
A wide variation in neurological and psychiatric symptoms was observed across the studies. The most frequently reported symptoms were headache, myalgia, seizure, confusion, encephalitis, and fatigue.
Prevalence of neurological and psychiatric symptoms
The findings of the meta-analysis revealed that myalgia has the highest prevalence (55%), followed by headache (53%), fatigue (36%), seizure (2.7%), confusion (2.4%), and encephalitis (2%).
Other neuropsychiatric symptoms that were not included in the meta-analysis were dizziness, pain, altered vision, encephalopathy, photophobia, depression, anxiety, and suicidal tendency.
Study significance
This systematic review provides a comprehensive overview of the prevalence of a range of neuropsychiatric symptoms commonly observed in individuals infected with the monkeypox virus.
Among various symptoms, myalgia and headache were present in more than 50% of the study population. However, more severe neurological complications including encephalitis, confusion, and seizure have a low prevalence among monkeypox-infected individuals.
As mentioned by the scientists, a high prevalence of non-specific symptoms such as myalgia and headache could be due to a common systemic reaction to viral infection. These symptoms might not be associated with direct neurological damage.
Studies reporting psychiatric symptoms have indicated that the presence of anxiety, depression, or low mood is common among hospitalized patients with monkeypox infection. However, none of these studies have assessed psychiatric symptoms using standardized scales. This makes it difficult to understand the clinical significance of these symptoms.
Given the observed prevalence of neuropsychiatric symptoms, the scientists recommend long-term monitoring of clinical consequences associated with monkeypox infection, as well as the implementation of a psychological support system for isolated/quarantined patients who are more prone to emotional distress.

This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources
Journal references:
- Preliminary scientific report.
Badenoch JB. 2022. Neurological and psychiatric presentations associated with human monkeypox virus infection: a systematic review and meta-analysis. MedRxiv. doi: https://doi.org/10.1101/2022.07.03.22277069 https://www.medrxiv.org/content/10.1101/2022.07.03.22277069v1
- Peer reviewed and published scientific report.
Badenoch, James B., Isabella Conti, Emma R. Rengasamy, Cameron J. Watson, Matthew Butler, Zain Hussain, Ben Carter, et al. 2022. “Neurological and Psychiatric Presentations Associated with Human Monkeypox Virus Infection: A Systematic Review and Meta-Analysis.” EClinicalMedicine, September, 101644. https://doi.org/10.1016/j.eclinm.2022.101644. https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(22)00374-1/fulltext.