Two weeks ago an epidemic outbreak of monkeypox outbreaks was detected for the first time in the UK causing concern among public health experts.
The spread of cases of smallpox in monkeys is increasing around the world, and its transmissibility is still unknown. For this reason, it is necessary to inform health professionals to take the necessary precautionary measures, as well as the degree of contagiousness of the virus, stress the doctors of the Therapeutic Clinic and the Medical School of the National and Kapodistrian University of Athens, Gianna Rentziou, Theodora Psaltopoulou, Maria Kantzanou, Yannis Danasis, Rodanthi Eleni Syrigo, Panos Malandrakis, Dimitris Paraskevis and Thanos Dimopoulos (Dean of the National Academy of Sciences), summarizing the latest data on monkeypox as published in the scientific journal Nature.
Epidemiology-Pathogenesis-Clinical picture-Diagnosis-Treatment
Monkeypox virus belongs to the genus Orthopoxvirus of the family Poxviridae, the same genus as variola, which causes smallpox and has been eradicated worldwide since 1980. The simian smallpox virus was first discovered in 1958 in monkey colonies and was first identified in humans in 1970 in the Congo. Since then, local outbreaks have been observed in West and Central African countries, with the latest and most significant outbreak in Nigeria with more than 500 confirmed and suspected cases. In Europe, and in particular the UK, seven travel-associated cases have been detected since 2018 in endemic countries.
The incubation period is usually 5-21 days and the virus is transmitted between people through the respiratory system by inhalation of large droplets and through contact with skin lesions or infected materials (e.g. bed linen or towels used by a patient). The disease is manifested by fever, headache, myalgia, lymphadenopathy and a rash, usually starting on the head and extending to the trunk and including the palms of the hands. The rash initially appears in the form of spots and papules, which develop into small blisters, pustules and then into vesicles which eventually subside. This rash is sometimes confused with the chickenpox rash. The disease usually lasts 2-4 weeks and in the majority of cases is self-limiting. Diagnosis is made by isolation of the virus in culture, detection of viral DNA by PCR in a clinical specimen or detection of the presence of orthopox-virus in tissues by immunohistochemical methods.
Treatment focuses mainly on improving the symptoms. Regarding antiviral therapy, two drugs approved for the treatment of smallpox are also considered effective against monkeypox: tecovirimat, treatment of choice in combination with brincidofovir in patients with severe disease. Mortality in African countries ranges between 1-10% for Central African strains, while for West African strains, which are those identified in the recent outbreak in Europe, mortality in Africa is about 3%. No deaths were recorded in the epidemic outbreaks in the Western Hemisphere.
Why is monkeypox virus of concern as a public health pathogen?;
One of the main causes for concern is the sharp rise in cases, with 145 cases (confirmed and suspected) recorded by the afternoon of 21 May in 9 European countries as well as in the United States, Canada, Australia and Israel, according to Moritz Kraemer, PhD, Associate Professor at the University of Oxford. Also, another cause for concern is the possibility of human-to-human transmission without a history of travel to an endemic area, which means there is horizontal transmission in the community. The bigger question, as Andrea McCollum, an epidemiologist in the CDC's Poxvirus Division, points out, is how easily it is transmitted from person to person. For this reason, Mr. Osterholm, director of the University of Minnesota's Center for Infectious Diseases, predicts the possibility of dynamic transmission of the virus because of its as yet unknown transmissibility. Jennifer McQuinston, deputy director of the United States Center for Disease Control and Prevention, said that «given the confirmed cases in Portugal, and the suspected cases in Spain, and given the finding of cases in many countries around the world, it is still unknown how large the spread of the virus will be, and because of the frequent movement between countries, we will see cases around the world.» Finally, Marion Koopmans, DVM, PhD, director of an Erasmus department focusing on virus research, says the outbreak is starting to be worrying as cases are being found in different countries, unusual for monkeypox virus, which is not as contagious.
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