For the second time in two years, on 14 August 2024, a ‘International Public Health Emergency’ for Mpox, New Name for Monkeypox Virus. The cause is to be found in the surge in cases recorded in the Democratic Republic of Congo this year (over 15,600 cases and 537 deaths) and in the spread of the epidemic to a growing number of African countries. Experts from the Department of Infectious Diseases of the Istituto Superiore di Sanità explain in this in-depth article the most important things to know about this virus.
When asked what is Mpox and what is the current situation? The ISS experts say that “It is a viral disease caused by the monkeypox virus (mpxv), an orthopoxvirus of the same family as smallpox (poxviridae). There are two genetically distinct groups: clade I, which can be divided into two subclades Ia and Ib, and clade II, which can be divided into two subclades IIa and IIb. The virus – a note reports – is present in wildlife, particularly primates and small rodents, in several countries in Central and West Africa. The name monkeypox, previously attributed to it, derives from the first identification of the virus, discovered in monkeys in a Danish laboratory in 1958The virus was first detected in humans in 1970, in the Democratic Republic of Congo (DRC).
Since then, human cases transmitted predominantly through contact with infected animals have been reported in DRC and other African countries. In 2022, the rapid spread of mpox clade IIb globally, to previously unaffected countries, with human-to-human transmission, predominantly sexual, was also declared a Public Health Emergency of International Concern, which ended in May 2023. Another major mpox outbreak has been ongoing in DRC since late 2023, which has recently spread to other African countries. Of particular concern is the current rapid spread of mpxv clade I and in particular, a new subclade Ib strain, which appears to be spreading predominantly through sexual contact.
The number of cases reported this year in the DRC – it reads – has already surpassed last year’s total numberwith more than 15,600 cases and 537 deaths. In the last month alone, more than 100 laboratory-confirmed cases of mpox clade 1b have been reported in four countries bordering DRC, where no cases had previously been detected: Burundi, Kenya, Rwanda and Uganda. The true number of cases is also thought to be higher, as most cases with clinical presentation compatible with mpox infection are not being laboratory tested. The emergence of a new mpox subtype, its rapid spread in eastern DRC and the reporting of cases in several neighbouring countries have been assessed as very concerning, leading WHO to consider a coordinated international response necessary to halt the spread of the virus, resulting in the declaration of a Public Health Emergency of International Concern .
Incubation and symptoms
After a incubation period which can vary from 5 to 21 days (usually 6 to 13 days), the disease is generally characterized by: a prodromal phase, which lasts between 0 and 5 days, with fever, intense headache (generalized or frontal), lymphadenopathy (swollen lymph nodes), back pain, myalgia and intense asthenia (weakness). lymphadenopathy is a distinguishing feature of monkeypox from other diseases that may initially appear similar (e.g., chickenpox); a rash that usually appears within 1 to 3 days of the onset of fever, typically starting on the face (involved in 95% of cases) and then spreading to other parts of the body, especially the extremities (including the palms and soles in 75% of cases). The oral mucosa (in 70% of cases), genitals (30% of cases), and conjunctivae (20%) may also be involved. Ocular involvement may lead to corneal ulcers and blindness. The skin rash It usually progresses sequentially from macules (flat-based lesions) to papules (solid, slightly raised lesions), vesicles (clear fluid-filled lesions), pustules (yellow fluid-filled lesions), and crusts that dry and fall off. The number of lesions varies from a few to several thousand. Unlike chickenpox, the lesions are generally the same size and at the same stage of maturation per anatomic site.
Atypical manifestations
In the 2022 global epidemic, some differences have been found in the incubation period which can vary from 7 to 8 days with even shorter periods of 2 to 4 days. In addition, there have been atypical clinical pictures described which differ in some respects from what has generally been described in past Mpox outbreaks in endemic countries. The prodromal symptoms that precede the rash do not always occur, and are absent in almost 50% of cases.
Atypical manifestations included the appearance of genital lesions as the first symptomwithout a prodromal phase, and predominantly anogenital or oropharyngeal lesions with or without fever or systemic symptoms. In some cases, clinical manifestations have been limited to the appearance of a single lesion (cutaneous, anogenital or oropharyngeal). Subclinical/asymptomatic cases have also been described. Typical complications of monkeypox may include secondary bacterial infections, bronchopneumonia, sepsis, encephalitis and corneal infection resulting in vision loss. Genital, perianal and oral complications, including proctitis and tonsillitis, have also been described.
Duration
Mpox is usually a self-limiting disease and It usually lasts 2 to 4 weeks. Some people may develop more severe disease and require hospitalization. Those at highest risk include children, pregnant women, and people with compromised immune systems including HIV infection. The prognosis of the disease depends on multiple factors including previous vaccination status, the person’s initial health status, concomitant diseases, and comorbidities.
Until 2022 – the ISS experts underline – the mpox epidemics were linked to spillover events from animals to humans, with poor human-to-human transmissibility, and with the Mmxv clade I present in Central Africa, while the clade II in West Africa. In 2022, the MPXV sub-clade IIb caused a global epidemic, supported by human-to-human contagion almost exclusively through sexual contact. Human transmission can also occur through contact with infected material from skin lesions or with contaminated objects (sheets, clothes), or prolonged face-to-face contact (through respiratory droplets).
Transmission and vaccine
In the current epidemic, in countries with cases of mpox clade I, it is human-to-human transmission has been documented, as well as transmission through both sexual and non-sexual contact.. The modes of transmission during the current epidemic remain to be clarified and further explored. In particular, in the DRC, the majority of cases and deaths in the DRC occurred in children under 15 years of age (66% of cases and 82% of total deaths), indicating a non-sexual transmission route (close contact and respiratory route).
AND It is possible that people who have been vaccinated against smallpox (a vaccination abolished in Italy in 1981) are at lower risk of infection with monkeypox virus due to the similarity of the latter to the human smallpox virus. An attenuated non-replicating vaccine (MVA-BN) is currently available that is even safer than the one used during the human smallpox eradication campaign, which ended between the late 70s and early 80s of the last century, and is also effective against monkeypox virus. In the current epidemiological context, vaccination is not recommended for the general population. At the moment, vaccination is offered to some categories of people who are more at risk.
Advice
ECDC recommends that travellers to epidemic areas consult their physician or international vaccination/travel medicine centres regarding suitability for monkeypox vaccination. Recommendations to follow include:
1. Use a condom when having sex with someone whose health status you do not know; although a condom does not provide complete protection against Mpox infection (as the virus can be transmitted through direct contact with other areas of the body), it can reduce transmission through semen.
2. Abstain from sexual or other contact with individuals with possible or known Mpox infection and with persons with visible lesions or other symptoms compatible with Mpox.
3. Do not share utensils or cups with a person with Mpox.
4. Do not handle or touch the bedding, towels, or clothing of a person with Mpox.
5. Wash your hands thoroughly with soap and water after each contact with a person or animal with Mpox. If soap and water are not available, use an alcohol-based hand sanitizer.
6. Avoid contact with wild animals.
7. If you are traveling to endemic areas or attending mass events, avoid contact with people whose health status you do not know and consult your doctor before leaving to assess the opportunity and suitability for smallpox vaccination.
8. For those returning from trips to endemic areas, in case of symptoms compatible with Mpox, carry out diagnostic tests as soon as possible
The ECDC has raised, in agreement with the Ministry of Health, the level of activation of event-based surveillance in Italy. The ISS – the note concludes – in agreement with the Ministry of Health, ECDC and WHO contributes with its experts to the constant monitoring of the infection on the territory.
#Monkeypox #Answers #Symptoms #Transmission #Treatment
