Cases of suspected and confirmed Monkeypox are being investigated in a number of European countries, the US, Canada and the UK. The most recent confirmed cases were reported in Italy and Sweden. It follows the confirmation of cases in the US, Spain and Portugal on Wednesday, as well as the investigation of 13 suspected cases in Canada. Two more people with monkeypox have been identified, taking the total number of cases in the UK to nine.
A Rare Viral Illness
Monkeypox is a rare but potentially serious viral illness that typically begins with flu-like illness and swelling of the lymph nodes and progresses to a rash on the face and body.
Monkeypox is usually mild and from which most people recover in a few weeks. The virus does not spread easily between people and the risk to the wider public is said to be very low. It is most common in remote parts of Central and West Africa. Cases of the disease outside of the region are often linked to travel to the area. Anyone can get monkeypox. However, it’s more common in children. Of cases in Africa, 90% were among children under 15 years old.
Why Is It Called Monkeypox?
Monkeypox virus belongs to the Orthopoxvirus genus in the family Poxviridae. It was first discovered in 1958 when two outbreaks of a pox-like disease occurred in lab monkeys kept for research, hence the name.
But monkeys might not be the ones to blame for outbreaks, and the natural reservoir of monkeypox remains unknown, though the WHO says rodents are the most likely. In Africa, evidence of monkeypox virus infection has been found in many animals including rope squirrels, tree squirrels, Gambian poached rats, dormice, different species of monkeys.
Monkeypox was not recognized as a cause of human illness until 1970, 3 years after the start of the WHO’s intensified smallpox eradication program. Prior to 2003, monkeypox was limited to parts of central and western Africa, where it is believed to be endemic in several species of small mammals. In 2003, an outbreak of human monkeypox occurred in the United States. Seventy-two cases were reported, of which 37 were laboratory confirmed. The outbreak was linked to prairie dogs that had been housed with exotic animals shipped from Ghana. There were no deaths and no human-to-human transmission was proven.
The virus is mainly transmitted to humans while handling infected animals or by direct contact with the infected animal’s body fluids, or lesions. Monkeypox can be transmitted by droplet exposure via exhaled large droplets and by contact with infected skin lesions or contaminated materials. Human to human transmission occur through respiratory route but previously so many studies are conducted to prove that monkey pox virus was not transmitted through the respiratory route both in animals and humans. But now monkey pox is able to survive in humans due to genetic changes and human to human transmission is possible.
A Potential Bioterrorism Agent
Bioterrorist attacks occupy a special place amongst the innumerable potential types of terrorist attack, with the intentional release of pox viruses being especially feared in this connection. Apart from the variola virus, the agent responsible for smallpox in humans, the monkeypox virus and numerous other animal pox viruses pose potential risks for humans and animals. This risk scenario also includes recombinations between the various pox viruses, changes in hosts and genetically engineered manipulations of pox viruses.
The discontinuation of general vaccination in the 1980s has given rise to increasing susceptibility to monkeypox virus infection in the human population. This has led to fears that monkeypox virus could be used as a bioterrorism agent. Because it can be used as bioweapon, So there is a great need of having an antiviral drug which is effective against monkey pox virus.
A Tale of Two Clades
There are two clades of monkeypox virus: the West African clade and Congo Basin (Central African) clade. Although the West African clade of monkeypox virus infection sometimes leads to severe illness in some individuals, disease is usually self-limiting. The case fatality ratio for the West African clade has been documented to be around 1%, whereas for the Congo Basin clade, it may be as high as 10%.
Signs and Symptoms
In humans, the symptoms of monkeypox are similar to but milder than the symptoms of smallpox. Monkeypox begins with fever, headache, muscle aches, and exhaustion. The main difference between symptoms of smallpox and monkeypox is that monkeypox causes lymph nodes to swell (lymphadenopathy) while smallpox does not. The incubation period (time from infection to symptoms) for monkeypox is usually 7−14 days but can range from 5−21 days.
The illness begins with fever, headache, muscle aches, backache, swollen lymph nodes, chills and exhaustion. Within 1 to 3 days (sometimes longer) after the appearance of fever, the patient develops a rash, often beginning on the face then spreading to other parts of the body.
Lesions progress through successive stages before falling off . The stages are macules, papules, vesicles, pustules and scabs. The illness typically lasts for 2−4 weeks. In Africa, monkeypox has been shown to cause death in as many as 1 in 10 persons who contract the disease.
Milder cases of monkeypox may go undetected and represent a risk of person-to-person transmission. There is likely to be little immunity to the infection in those travelling or otherwise exposed, as endemic disease is normally geographically limited to parts of West and Central Africa.
Historically, vaccination against smallpox was shown to be protective against monkeypox. While one vaccine (MVA-BN) and one specific treatment (tecovirimat) were approved for monkeypox, in 2019 and 2022 respectively, these countermeasures are not yet widely available, and populations worldwide under the age of 40 or 50 years no longer benefit from the protection afforded by prior smallpox vaccination programmes.
Complications of Monkeypox include bacterial superinfection of skin, permanent skin scarring, hyperpigmentation or hypopigmentation, permanent corneal scarring (vision loss), pneumonia, dehydration (vomiting, diarrhea, decreased oral intake due to painful oral lesions, and insensible fluid loss from widespread skin disruption), sepsis, encephalitis and death. Monkeypox causes death in up to 10% of cases.
Children are also at higher risk, and monkeypox during pregnancy may lead to complications, congenital monkeypox or stillbirth.
A smallpox vaccine can provide protection against monkeypox, but its use is currently limited to people who work in a lab with the variola (smallpox) virus. Prevention depends on decreasing human contact with infected animals and limiting person-to-person spread. Avoiding contact with infected animals (especially sick or dead animals). Avoiding contact with bedding and other materials contaminated with the virus. Washing your hands with soap and water after coming into contact with an infected animal. Thoroughly cooking all foods that contain animal meat or parts. Avoiding contact with people who may be infected with the virus. Using personal protective equipment (PPE) when caring for people infected with the virus.