A rare condition known as monkeypox has been confirmed in the USA and Europe, with more suspected cases worldwide. Monkeypox scare is rising globally as several countries report the rare viral infection, including the USA. Since 13th May 2022, cases of monkeypox have been reported to WHO (World Health Organization) from 12 Member States that are not endemic for the monkeypox virus across three WHO regions. This blog explains the symptoms, causes, and prevention of monkeypox.
What is monkeypox?
Monkeypox is an orthopoxvirus, a family of viruses that includes the now eradicated smallpox virus. Monkeypox is an infectious viral illness that can occur in humans and some other animals. Based on the available information, monkey virus cases have primarily but not exclusively been identified amongst men having sex with men (i.e., MSM) seeking care in primary care or sexual health clinics. Scientists first identified the monkeypox disease in 1958.
There were two outbreaks amongst monkeys used for research. That is why this condition is known as monkeypox. The first case of the monkeypox infection in a human happened in 1970 in the DRC or the Democratic Republic of the Congo. Monkeypox is a zoonotic virus, i.e., it is typically transmitted through close contact between a human and an animal, often through a scratch, bite, or contact with the rash and “fomites,” material such as bedding or clothes contaminated with the material from monkeypox lesions.
What are the symptoms of the monkeypox virus?
The early symptoms of the monkeypox virus include fever, headache, muscle pains, backache, shivering, and feeling extremely tired and exhausted. Typically there are swollen lymph nodes below the jaw, behind the ear, neck, or the groin. It is then followed by a rash that forms blisters and crusts over, most often in the mouth, on the face, feet, hands, genitals, and eyes. The time from exposure to the virus to onset of the symptoms is, on average, 12 days, though it ranges from about 5 to 21 days.
The duration of monkey virus symptoms is typically two to four weeks. Cases can be severe, especially in children, pregnant women, or individuals with suppressed immune systems. Three-quarters of the affected people have lesions on their soles and palms, more than two-thirds in their mouth, a third on their genitals, and one in five have lesions in their eyes. These begin as small flat spots before becoming small bumps. The bumps then fill with at first clear fluid and then yellow liquid. They subsequently burst and scab over.
There might be a few lesions or several thousand, at times merging to produce large lesions. The lesions evolve in the same stage in each part of the affected body. They look identical to the rash of smallpox. The rash generally lasts about ten days. An affected person can remain unwell for two to four weeks. After healing, the lesions can leave pale marks on the skin before becoming dark scars.
How does the monkeypox virus spread among humans?
Monkeypox in humans and animals is caused due to infection with the monkeypox virus – a double-stranded DNA virus in the genus Orthopoxvirus in the family of Poxviridae. The virus is found mainly in tropical rainforest regions of West and Central Africa. The monkeypox virus can spread between people in three ways:
- directly touching an infected person
- Inhaling respiratory droplets
- intimate or sexual contact with an infected person
- less frequently through indirect contact like handling an infected person’s clothing.
The respiratory route involves large droplets that do not linger in the air or travel far. Therefore, person-to-person spread typically needs prolonged and intimate contact. Most human cases of monkeypox are attained from an infected animal, though the route of transmission remains unclear. The virus can enter a person’s body through the respiratory tract, broken skin, or the mucous membranes of the nose, eyes, or mouth. Once a human is infected with the monkeypox virus, transmission to other humans is possible, with hospital staff and family members at exceptionally high risk of infection.
Human-to-human transmission occurs primarily through close contact with an infected person. There are indications that the transmission of the virus occurs during sexual intercourse. The animal-to-human transmission can occur by a bite or scratch, bush meat preparation, direct contact with the body fluids or lesion material, or indirect contact with the lesion material, such as through contaminated bedding. An animal can infect humans through a bite or by direct contact with the bodily fluids of an infected animal.
The monkeypox virus can also spread from human to human, by respiratory (or airborne) contact or by contact with the bodily fluids of an infected person. Risk factors for monkeypox virus transmission include sharing a room or bed or using the same utensils as the infected person. An increased risk of transmission is associated with elements, including the introduction of the virus to the oral mucosa.
What are the two forms of monkeypox?
There are two forms of the monkeypox virus, the West African and the Central African form. According to the WHO (World Health Organization), all the monkeypox cases whose samples have been confirmed by PCR have been from the West African clade. Monkeypox infections in the West African clade are less severe than in the Congo Basin (i.e., Central African) clade, and there is a lower case fatality rate. While most monkeypox cases are often within Africa, previous monkeypox outbreaks have shown up in the USA, Israel, and Singapore. The most recent outbreak in the United States was in 2003, with 47 cases.
What are the prevention strategies against the monkeypox infection?
The vaccines and drugs developed to treat or ward off smallpox can offer some protection against monkeypox. Monkeypox triggers milder illness than smallpox does. Smallpox antivirals with poxvirus activity such as Tembexa (Chimerix), Vistide (cidofovir, Gilead Sciences), and TPOXX (SIGA Technologies Inc) might be used against monkeypox.
Vaccination against smallpox may protect against human monkeypox infection since these are closely related viruses, and the vaccine protects animals against experimental lethal monkeypox challenges. However, this has not been conclusively demonstrated in humans, as routine smallpox vaccination was discontinued after the eradication of smallpox. The smallpox vaccine has been reported to minimize the risk of monkeypox amongst previously vaccinated persons in America.
The decrease in immunity to poxviruses in the exposed populations is a factor in the prevalence of the monkeypox infection. It is attributed to the waning cross-protective immunity amongst those vaccinated before the 1980s when mass smallpox vaccinations were discontinued. It could also be due to the gradually increasing proportion of unvaccinated individuals.
The USA Centers for Disease Control and Prevention (i.e., CDC) recommends that persons investigating the monkeypox outbreaks and caring for infected people or animals receive a smallpox vaccination to protect from monkeypox. Persons who have had intimate or close contact with humans or animals confirmed to have monkeypox must also be vaccinated.
Monkeypox is an infection caused due to a virus in the same family as smallpox. Monkeypox causes a similar (though less severe) illness than smallpox. Vaccines for smallpox can protect against monkeypox. If you develop the mentioned monkeypox symptoms, mainly if you develop a rash, swollen lymph nodes, and a fever, you should isolate yourself from others and seek medical attention. If you have blisters or a rash, ensure these are covered.