Monkeypox, its origin
Human monkeypox was first reported in humans in 1970 in the Democratic Republic of the Congo in a 9-month-old boy in a region where smallpox had been eliminated in 1968. Monkeypox is caused by monkeypox virus, a member of the Orthopoxvirus genus in the family Poxviridae. Monkeypox is usually a self-limited disease with the symptoms lasting from 2 to 4 weeks. Severe cases can occur.
Monkeypox, the outburst
Monkeypox is a viral zoonotic disease that occurs primarily in tropical rainforest areas of central and west Africa and is occasionally exported to other regions. An antiviral agent developed for the treatment of smallpox has also been licensed for the treatment of monkeypox.
Vaccines used during the smallpox eradication programme were known to provide protection against monkeypox. Newer vaccines have been developed of which one has been approved for prevention of monkeypox. A WHO report reveals the facts of the disease.
In recent times, the case fatality ratio has been around 3–6%. Monkeypox is transmitted to humans through close contact with an infected person or animal, or with material contaminated with the virus. Monkeypox virus is transmitted from one person to another by close contact with lesions, body fluids, respiratory droplets and contaminated materials such as bedding.
Signs and Symptoms
The invasion period is around 0–5 days characterized by fever, intense headache, lymphadenopathy,back pain, myalgia and intense asthenia. Lymphadenopathy is a distinctive feature of monkeypox compared to other diseases that may initially appear similar (chickenpox, measles, smallpox) the skin eruption usually begins within 1–3 days of the appearance of fever.
The rash tends to be more concentrated on the face and extremities rather than on the trunk. It affects the face (in 95% of cases), and palms of the hands and soles of the feet (in 75% of cases). Also affected are oral mucous membranes (in 70% of cases), genitalia (30%), and conjunctivae (20%), as well as the cornea. The rash evolves sequentially from macules to papules, vesicles, pustules, and crusts which dry up and fall off. The number of lesions varies from a few to several thousand. In severe cases, lesions can coalesce until large sections of skin slough off.
Preventing the spread
Creating awareness of risk factors and educating people about the measures they can take to reduce exposure to the virus is the main prevention strategy for monkeypox. During human monkeypox outbreaks, close contact with infected persons is the most significant risk factor for monkeypox virus infection. Health workers and household members are at a greater risk of infection.
Health workers caring for patients with suspected or confirmed monkeypox virus infection, or handling specimens from them, should implement standard infection control precautions.
Patient specimens must be safely prepared for transport with triple packaging in accordance with WHO guidance for transport of infectious substances. Unprotected contact with wild animals, especially those that are sick or dead, including their meat, blood and other parts must be avoided.
It is known that human-to-human transmission is limited, with the longest documented chain of transmission being 6 generations, meaning that the last person to be infected in this chain was 6 links away from the original sick person. It can be transmitted through contact with bodily fluids, lesions on the skin or on internal mucosal surfaces, such as in the mouth or throat, respiratory droplets and contaminated objects. Hence close contact with these bodily fluids must be avoided. Detection of viral DNA by polymerase chain reaction (PCR) is the preferred laboratory test for monkeypox. The best diagnostic specimens are directly from the rash – skin, fluid or crusts, or biopsy where feasible.
Management by Vaccination
Vaccination against smallpox has previously been demonstrated through several observational studies to be about 85% effective in preventing monkeypox. Evidence of prior vaccination against smallpox can usually be found as a scar on the upper arm. Presently, the original (first-generation) smallpox vaccines are no longer available to the general public. Some laboratory personnel or health workers may have received a more recent smallpox vaccine to protect them in the event of exposure to orthopoxviruses in the workplace.
A still newer vaccine based on a modified attenuated vaccinia virus (Ankara strain) was approved for the prevention of monkeypox in 2019. Smallpox and monkeypox vaccines are developed in formulations based on the vaccinia virus due to cross-protection afforded for the immune response to orthopoxviruses.
So therefore, in conclusion Monkeypox is less contagious than smallpox and causes less severe illness . Monkeypox typically presents clinically with fever, rash and swollen lymph nodes and may lead to a range of medical complications. However, more studies and vaccines are to be developed to completely eradicate this new disease.