Monkeypox is a rare, infectious disease that is caused by the monkeypox virus. The monkeypox virus can affect humans and certain animals.
The disease cases are often found close to the tropical rainforests, where there are animals that carry the monkeypox virus.
The disease may be spread from body fluids, handling bushmeat, contaminated objects, close contact with an infected person, or an animal scratch or bite. The monkeypox virus is believed to circulate among certain rodents in Africa naturally.
Evidence of monkeypox virus infection has been found in animals, including Gambian poached rats, squirrels, different species of monkeys, dormice, and others.
Diagnosis for the virus can be confirmed by testing a lesion for the virus’s DNA.
Cause of monkeypox
The following are the causes of Monkeypox disease:
Monkeypox virus
Monkeypox virus causes the disease in both animals and humans. The virus was first identified in 1958 as a pathogen of Macacafascicularis (crab-eating macaque monkeys), which was being used as laboratory animals.
The crab-eating macaque is commonly used for neurological experiments. Monkeypox virus is found mostly in tropical rainforest regions of West and Central Africa.
The virus is an Orthopoxvirus, a genus of the family Poxviridae that contains several other viral species that target mammals. It was discovered in monkeys in 1958, and in humans in 1970. Over 400 cases in humans were reported between 1970 and 1986.
Small viral outbreaks with a death rate of about 10% and a secondary human-to-human infection rate of about the same per cent occur routinely in equatorial West and Central Africa.
The main route of infection is thought to be in contact with the bodily fluids found in the infected animals, or when being in contact with infected animal directly.
The first reported outbreak that happened out of the African continent occurred in the United States in 2003 in the Midwestern states of Indiana, Illinois, New Jersey, and Wisconsin.
Also, the outbreak then was traced to a prairie dog that was infected from an imported Gambian pouch rat, but no deaths were recorded. Humans can be infected by direct contact with an infected animal’s bodily fluids, or by an animal through a bite.
Monkeypox virus can also be spread from human to human, by contact with an infected person’s bodily fluids or by respiratory (airborne) contact.
Risk factors for transmission include using the same utensils as an infected person or sharing a room or bed with an infected person.
Increased transmission risk is related to factors involving the introduction of the virus to the oral mucosa.
Reservoir
To monkeys, reservoirs for the virus are found in dormice (Graphiurus spp.), African squirrels (Heliosciurus, and Funisciurus), and Gambian pouched rats (Cricetomysgambianus).
The use of all these animals as food may be an essential source of transmission to humans.
Symptoms
Symptoms of the disease begin with headache, fever, swollen lymph nodes, muscle pains, and feeling tired. This is followed by a rash that forms crusts and blisters over.
The time from exposure to onset of symptoms is around 9-10 days while the duration of symptoms is typically 2 to 5 weeks.
Diagnosis
Diagnosis usually requires medical professional testing for the virus. The virus stays in the blood for very long, and hence blood testing may not spot the disease.
Prevention
Vaccination against smallpox is presumed to protect against human monkeypox infection because they are strongly associated with viruses.
Also, it was discovered that the vaccine protects animals from experimental lethal monkeypox challenge.
This has not been demonstrated in humans, owing to the safety concerns with the vaccine and because the routine smallpox vaccination was suspended following the apparent eradication of smallpox.
Smallpox vaccine has been reported to reduce the threat of monkeypox among previously vaccinated persons in Africa.
The reduction in immunity to poxviruses in exposed populations is a factor in the prevalence of monkeypox. It is attributed to the gradually increasing proportion of unvaccinated individuals.
The United States Centers for Disease Control and Prevention (CDC) recommends that individuals involved in caring for infected animals or individuals should receive a smallpox vaccination to protect against monkeypox. Also, individuals investigating monkeypox outbreaks should take the vaccination too.
Persons who have had intimate or close contact with animals or individuals confirmed to have monkeypox should also be vaccinated.
The CDC does not recommend pre-exposure vaccination for veterinary staff, animal control officers, or unexposed veterinarians unless such persons are involved in field investigations.
Treatment
Presently, no treatment for monkeypox is safe or effective. Several measures may be used to try to reduce the spread of the disease, including the cidofovir, vaccinia immune globulin (VIG), and smallpox vaccine.