Issued on: 26/06/2024 - 12:10

The name monkeypox was originally coined because the disease was first identified in laboratory monkeys. ^{https://en.wikipedia.org/wiki/Mpox#cite_note-CDC_About-3 - [3]}  This was subsequently criticised as a misnomer, because monkeys are not the main host or reservoir. It was also criticized because the name reinforced stigma about African countries as a source of disease. ^{https://en.wikipedia.org/wiki/Mpox#cite_note-pmid35710105-18 - [16]}

After requests by a number of public health organisations and scientists, who argued that these issues were harming the fight to contain the disease outbreak, ^{https://en.wikipedia.org/wiki/Mpox#cite_note-19 - [17]}  the subtypes of monkeypox virus were renamed clade I and clade II in August 2022. The World Health Organization announced in November 2022 that it "will adopt the term mpox in its communications, and encourages others to follow these recommendations". ^{https://en.wikipedia.org/wiki/Mpox#cite_note-Who291122-6 - [6]}

Transmission

Smallpox was highly contagious, but generally spread more slowly and less widely than some other viral diseases, perhaps because transmission required close contact and occurred after the onset of the rash. The overall rate of infection was also affected by the short duration of the infectious stage. In  https://en.wikipedia.org/wiki/Temperate - temperate  areas, the number of smallpox infections was highest during the winter and spring. In tropical areas, seasonal variation was less evident and the disease was present throughout the year. ^{https://en.wikipedia.org/wiki/Smallpox#cite_note-PinkBook-33 - [33]}  Age distribution of smallpox infections depended on  https://en.wikipedia.org/wiki/Acquired_immunity - acquired immunity .  https://en.wikipedia.org/wiki/Vaccination - Vaccination   https://en.wikipedia.org/wiki/Immunity_%28medical%29 - immunity  declined over time and was probably lost within thirty years. ^{https://en.wikipedia.org/wiki/Smallpox#cite_note-AFIP-34 - [34]}  Smallpox was not known to be transmitted by insects or animals and there was no  https://en.wikipedia.org/wiki/Asymptomatic_carrier - asymptomatic carrier  state. ^{https://en.wikipedia.org/wiki/Smallpox#cite_note-PinkBook-33 - [33]}

Transmission occurred through inhalation of  https://en.wikipedia.org/wiki/Airborne_disease - airborne  variola virus, usually droplets expressed from the oral, nasal, or  https://en.wikipedia.org/wiki/Pharynx - pharyngeal   https://en.wikipedia.org/wiki/Mucosa - mucosa  of an infected person. It was transmitted from one person to another primarily through prolonged face-to-face contact with an infected person. ^{https://en.wikipedia.org/wiki/Smallpox#cite_note-2012Spread-14 - [14]}

Some infections of laundry workers with smallpox after handling contaminated bedding suggested that smallpox could be spread through direct contact with contaminated objects ( https://en.wikipedia.org/wiki/Fomite - fomites ), but this was found to be rare. ^{https://en.wikipedia.org/wiki/Smallpox#cite_note-2012Spread-14 - [14] https://en.wikipedia.org/wiki/Smallpox#cite_note-:0-35 - [35]}  Also rarely, smallpox was spread by virus carried in the air in enclosed settings such as buildings, buses, and trains. ^{https://en.wikipedia.org/wiki/Smallpox#cite_note-FactSheet-32 - [32]}  The virus can cross the  https://en.wikipedia.org/wiki/Placenta - placenta , but the incidence of  https://en.wikipedia.org/wiki/Congenital - congenital  smallpox was relatively low.

Later today (2:00 PM – 3:00 PM ET) the CDC will hold a COCA call for clinicians on the continually evolving Mpox threat. The clade IIb outbreak which was  https://afludiary.blogspot.com/2022/07/who-director-declares-monkeypox-public.html - - continue to see sporadic infections  around the globe. 

At the same time a far more dangerous clade I mpox virus continues to rage in the DRC.

Mpox is a  https://www.cdc.gov/onehealth/basics/zoonotic-diseases.html - zoonotic disease , which means it can spread between animals and people. The exact source of mpox in nature is not known, but it is believed that small mammals, such as rope and sun squirrels, giant-pouched rats, and African dormice may carry the virus in parts of West and Central Africa.

People can get infected with the virus through direct contact with infected animals, often while hunting, trapping, and processing infected animals or their body parts and fluids. Small mammals can carry the virus without symptoms, while non-human primates like monkeys can get sick with mpox and have signs of disease like humans.

What We Know About Mpox in Animals

• Monkeypox virus can infect a wide range of mammal species, including monkeys, anteaters, hedgehogs, prairie dogs, squirrels, and shrews.
• We are still learning which species of animals can get infected with Monkeypox virus. While we do not know if reptiles, amphibians, or birds can get mpox, it is unlikely since these animals have not been found to be infected with other orthopoxviruses.
• Not all animals have a rash when they have mpox.
• Infected animals can spread Monkeypox virus to people and other animals, and it is possible that people who are infected can spread Monkeypox virus to animals through close contact.
• Monkeypox virus can be found in the rash caused by mpox (scabs, crusts, fluids) and infected body fluids, including respiratory secretions, and potentially in urine (pee) and feces (poop).

What We Know About Mpox in Pets

• We don’t know for sure if pets like dogs and cats can be infected with Monkeypox virus, but it may be possible.
• People with mpox could possibly spread the virus to pets through close contact, including petting, cuddling, hugging, kissing, licking, sharing sleeping areas, and sharing food.

No pets or other animals were confirmed to have mpox during the global mpox outbreak that began in 2022.

During 2023, a Clade I outbreak of mpox disease in the DRC resulted in 14,626 suspected cases being reported, with 654 associated deaths, making for a case-fatality rate (CFR) of 4.5%. The outbreak continued into 2024 with an additional 3,576 suspected mpox cases and 265 deaths being reported in the DRC through the first 9 weeks of the year, making for an estimated CFR of 7.4%. ^{https://en.wikipedia.org/wiki/Mpox_in_the_Democratic_Republic_of_the_Congo#cite_note-drcmpox-17 - [17]}

The outbreak appears to be of a primarily sexually transmitted nature and cases are occurring in areas without a history of mpox, such as South Kivu and Kinshasa. The outbreak seems to consist of two separate sub-variants of clade I, with one of the sub-variants having a novel mutation making detection with standard assays unreliable. ^{https://en.wikipedia.org/wiki/Mpox_in_the_Democratic_Republic_of_the_Congo#cite_note-drcmpox-17 - [17]}

The outbreak spread to the neighbouring country of the  https://en.wikipedia.org/wiki/Republic_of_Congo - Republic of Congo , with 43 mpox cases being reported in March 2024.

While much of the world expressed surprise when a clade IIb Mpox (then called Monkeypox) virus began its world tour in the spring of 2022, experts had been warning for years it was not only possible, but increasingly likely. 

Cautionary reports published between 2020 and early 2022 include:
https://afludiary.blogspot.com/2022/02/plos-ntd-changing-epidemiology-of-human.html -

https://afludiary.blogspot.com/2022/02/plos-ntd-changing-epidemiology-of-human.html - PLoS NTD: The Changing Epidemiology of Human Monkeypox—A potential threat?

https://afludiary.blogspot.com/2021/02/eid-journal-reemergence-of-human.html - EID Journal: Reemergence of Human Monkeypox and Declining Population Immunity - Nigeria, 2017–2020

https://afludiary.blogspot.com/2020/08/who-modelling-human-to-human.html - WHO: Modelling Human-to-Human Transmission of Monkeypox

While largely ignored, 2 distinct clades of Mpox (I & II) had been spreading across central Africa for decades, mostly in a handful of endemic countries (clade I primarily in the DRC & CAR), with  https://afludiary.blogspot.com/2018/03/mmwr-emergence-of-monkeypox-west-and.html - a weaker clade II virus re-emerging in Nigeria  after an absence of 40 years in 2017. 

Luckily, it has been the far less-dangerous Clade IIb that has been spreading internationally for the past 2 years.  Deaths have only rarely (< 2%)  https://www.cdc.gov/poxvirus/mpox/response/2022/world-map.html - been reported . 

But we've seen recent increases in the spread of the more pathogenic clade I virus in the DRC, including the emergence of a new, and apparently more transmissible, clade Ib virus (see  https://afludiary.blogspot.com/2024/03/eurosurveillance-ongoing-mpox-outbreak.html - Eurosurveillance: Ongoing Mpox Outbreak in South Kivu Province, DRC Associated With a Novel Clade I Sub-lineage ).

While the future course and impact of Mpox is unknowable, there are growing concerns that clade Ib might follow in the footsteps of clade IIb - or worse - clade I could evolve into an even more formidable virus before breaking out of Central Africa.