In May 2022, multiple cases of monkeypox were detected in the UK, confirming the continued spread of the monkeypox outbreak. The first confirmed case occurred on 6 May, when the person visited Nigeria (a monkeypox-endemic area). Since 18 May, an increasing number of countries and territories have reported cases, mainly in European countries, with outbreaks also occurring in North and South America, Asia, Africa and Australia. As of 21 August 2022, 80 countries and territories have been affected by the outbreak and more than 42,000 confirmed cases of monkeypox and 114 deaths have been reported, and on 23 July 2022, the World Health Organization declared the 2022 monkeypox outbreak to constitute a "public health emergency of international concern".
The outbreak marks the first time the disease has spread widely outside Central and West Africa. Health authorities stress that anyone can contract the disease, especially when they have close contact with a symptomatic person. WHO's preliminary assessment indicates that the outbreak is expected to be under control and will have less impact on the general population in the affected countries. But a recent statement from the group acknowledged that unmonitored transmission has been taking place for some time and called for urgent action to curb it.
Monkeypox is a zoonotic infectious disease caused by the monkeypox virus. Early symptoms of monkeypox infection include fever, headache, muscle pain, swollen lymph nodes, chills, and tiredness, after which a blister-like rash appears on the body and heals. The duration of symptoms is usually 2 to 4 weeks. Of the monkeypox infections prior to this outbreak, 1% to 3% of infected people have died (untreated); Pediatric cases are more likely to be severe.
Overview of the disease
Monkeypox is a zoonotic infectious disease caused by a virus, in which pathogens are transmitted from animals to humans. Early symptoms of monkeypox infection include fever, headache, muscle pain, swollen lymph nodes, chills and tiredness, followed by a blister-like rash on the body and healing; Some patients develop a rash first, or only a rash. The incubation period is usually 7 to 14 days, but it can also be 5 to 21 days; The duration of symptoms is usually 2 to 4 weeks. Among the recorded cases, the proportion of deaths was between 0 and 11%, and the proportion of young children dying was even higher. The vast majority of patients recover.
Monkeypox is caused by the monkeypox virus, which belongs to the same genus as smallpox virus [). It is believed that the virus is commonly transmitted among certain rodents in Africa. Monkeypox viruses that have infected humans are divided into two types: the West African branch and the Congo Basin branch, the latter also known as the Central African branch; The West African type causes milder symptoms than the Central African (Congo Basin) type. Monkeypox causes symptoms similar to smallpox, but not as severe as smallpox. Diagnosis is by testing viral DNA at the site of the lesion. The West African branch fatality rate of this outbreak is low, about 1%.
Route of transmission
Human-animal transmission
The routes of human-animal transmission of monkeypox virus include direct contact with the body fluids or lesions of infected animals, eating the meat of infected animals, being scratched or bitten by animals, and touching contaminated objects.
After two men living in Paris, France, were diagnosed with monkeypox, the Italian Lingti dog was also detected with the virus, which is the world's first case of "monkeypox human-to-dog transmission".
Human-to-human transmission
Monkeypox is transmitted from person to person through close contact with people with monkeypox rashes, including through face-to-face, skin-to-skin, mouth-to-mouth, or mouth-to-skin contact, including sexual contact. It is uncertain how long the infectivity of monkeypox patients will last, but in general, monkeypox patients are contagious until all lesions scab, scabs fall off, and new skin grows underneath.
The environment can be contaminated with monkeypox virus, for example when an infected person has been exposed to clothing, bedding, towels, objects, electronic devices, and surfaces. Others may become infected when exposed to these items. Infections may also result from inhalation of dander or viruses on clothing, bedding, or towels. This is called contaminant transmission.
Ulcers, lesions, or wounds in the mouth can be contagious, meaning that the virus can be transmitted through direct contact with the mouth, respiratory droplets, or through short-range aerosols. However, the possible mechanisms by which monkeypox spread through the air are unclear.
The virus may also be transmitted from pregnant women to fetuses, through skin-to-skin contact after birth, or from parents with monkeypox to infants or children.
While asymptomatic infection has been reported, it is unclear whether people without any symptoms will transmit the disease or whether it will be transmitted through other bodily fluids. Fragments of monkeypox virus DNA have been found in semen, but it is unclear whether the infection will be transmitted through semen, vaginal fluid, amniotic fluid, breast milk or blood. Research is underway to further understand whether people can spread monkeypox by exchanging these bodily fluids during and after a symptomatic infection.
WHO recommends that any illness that develops during travel or upon return from endemic areas should be reported to health professionals, including all recent travel and immunization histories, and that people in endemic areas avoid contact with diseased animals that may carry monkeypox virus, such as rodents, marsupials and primates, and avoid eating or handling wild animals or game meat, cooking animal meat products thoroughly cooked, and hand hygiene cleaning with soap and water or alcohol-based disinfectants.
There are currently no treatments approved specifically for monkeypox, but some antiviral drugs against smallpox may be effective against monkeypox. In the past, the first-generation vaccinia virus-based smallpox vaccine was 85% effective against monkeypox.
Monkeypox is endemic in West and Central Africa. The first human case of monkeypox occurred in the Democratic Republic of the Congo in 1970, after which an average of several thousand cases were detected annually in Africa but rarely outside africa. Prior to the 2022 outbreak, there were only 7 recorded cases of monkeypox in the UK, all of which were imported cases from Africa or health care workers treating these cases. The first three cases occurred in 2018, one more case was reported in 2019 and three more in 2021. The only severe monkeypox outbreak recorded in Western countries before 2022 was the 2003 Midwest monkeypox outbreak in the United States, where the pathogen originated from rodents imported from Africa, but there was no community transmission in this outbreak.
United Nations agencies
On 20 May, the World Health Organization (WHO) held an emergency meeting to discuss the outbreak and assess the extent of the threat. On 29 May, the World Health Organization assessed the global public health risk assessment of monkeypox as moderate. Its Head of Europe, Hans Kruger, expressed concern that infections in Europe could accelerate as people gather for parties and festivals during the summer months. The World Health Organization is expected to provide an update on the sequencing of the viral genome in different cases to determine the etiology.
UNAIDS urges the media, governments and communities to adopt a rights-based, evidence-based approach to respond by avoiding stigma, reaffirming that the disease can affect anyone and that the risks are by no means limited to men who have sex with men.
On 21 July, the World Health Organization called for a second meeting on the monkeypox outbreak. On 23 July, the World Health Organization declared the monkeypox outbreak a global public health emergency.