Potentially Asymptomatic Infection of Monkeypox Virus: A Systematic Review and Meta-Analysis

Abstract

Background: Monkeypox is a global public health concern, given the recent outbreaks in non-endemic countries where little scientific evidence exists on the disease. Specifically, there is a lack of data on asymptomatic monkeypox virus infection. This study aims to evaluate the overall prevalence of asymptomatic monkeypox virus infection. Methods: In this systematic review and meta-analysis, we performed an extensive literature search in PubMed, Scopus, Web of Science, ProQuest, EMBASE, EBSCOHost, Cochrane, and preprint servers (medRxiv, arXiv, bioRxiv, BioRN, ChiRxiv, ChiRN, and SSRN) and assessed all published articles till September 2022. Primary studies reporting monkeypox infections among asymptomatic participants were included after quality assessment. The characteristics of the study and information on the number of cases and symptomatic status were extracted from the included studies. The heterogeneity between studies was assessed using the I2 statistic. Publication bias was analyzed using funnel plots and Egger regression tests. The primary outcome was the pooled prevalence of asymptomatic infections within the examined population. Results: A total of 16 studies were included for qualitative synthesis, while five studies, including 645 individuals, were included for quantitative synthesis. There was substantial heterogeneity between studies (I2 = 94.86%; p < 0.01), with a pooled percentage of asymptomatic infections in the studied population of 10.2% (95%CI, 2.5–17.9%). Conclusion: This meta-analysis suggests that many people infected with the monkeypox virus are asymptomatic and difficult to detect. Therefore, prompt detection of these cases of monkeypox virus and appropriate subsequent management is of utmost importance to global public health.

Clinical features and outcome of human Mpox (Monkeypox) in Saudi Arabia: An observational study of travel-related cases

“…These cases with no sexual contacts reported contacts with apparently healthy individuals. The infectivity period for Poxviruses is typically linked to active skin lesions; however, serological studies in Africa suggest a possible role of asymptomatic/presymptomatic transmission with a pooled estimates of asymptomatic infections in a meta-analysis of 10.2% (95% CI, 2.5–17.9%) [31] . Another study, in 2022, showed that 25% of cases had known contact with confirmed Mpox cases, raising the possibility of the occurrence of asymptomatic or pauci-symptomatic transmission [32] .…”

Epidemiologic Situation of HIV and Monkeypox Coinfection: A Systematic Review

“…The World Health Organization (WHO) designated the current outbreak of Mpox disease as a Public Health Problem of International Concern on 23 July 2022 [ 4 ]. In addition, 83,487 cases were found in 110 countries by 23 December 2022 [ 5 ].…”

Effect of prior immunisation with smallpox vaccine for protection against human Mpox: A systematic review

“…It is a global emerging infectious disease threat evidenced by increasing its incidence day by day. Although the first monkeypox case was found in laboratory monkeys in Denmark in 1958, the first human case was discovered in the Democratic Republic of the Congo in 1970 2,3 . The first case of monkeypox in the USA was reported in 2003, before that the cases were only endemic in African countries such as Cameroon, Central Africa Republic, the Democratic Republic of the Congo, and Nigeria 2 .…”

“…According to the Centers for Disease Control and Prevention, there has been an unrivalled spread of the monkeypox virus started in May 2022 which now encompasses a total of 83,539 confirmed cases of 28 December 2022, in more than 100 countries, the majority of which in formerly non‐endemic counties. So, WHO (World Health Organization) declared the contemporary epidemic of monkeypox as a Public Health Emergency of International Concern (PHEIC) 3 …”

“…So, WHO (World Health Organization) declared the contemporary epidemic of monkeypox as a Public Health Emergency of International Concern (PHEIC). 3 Though the most common modes of human monkeypox transmission in the previous outbreak were due to contact with infected animal body fluids (i.e., blood, urine, and saliva), skin lesions, or respiratory droplets, travels to the endemic regions, etc., in 2022 outbreak, most cases were detected in men who have sex with men. 3 The current outbreak in 2022 has less than a 5% case fatality rate but in the case of immunodeficient individuals, the outcome can be more fatal.…”