Mpox

Key Facts

This virus previously referred to as monkeypox is a viral infection caused by the monkeypox virus belonging to the genus Orthopoxvirus. The two main clades of this virus are clade I (with subclades Ia and Ib) and clade II (with subclades IIa and IIb). Clade IIb strain caused a global outbreak of mpox in 2022-2023.

Mpox still exists in our midst even today, with a surge in cases of clades Ia and Ib causing anxiety especially these cases have been seen in some countries like Democratic Republic of Congo.

There are vaccines for mpox. It is recommended that vaccination be combined with other public health measures to prevent the spread of monkeypox.

Typically, common signs include skin rash or mucosal lesions that last about two to four weeks along with fever, headache, muscle pain, backache, malaise and lymphadenopathy.

The disease can be transmitted through person-to-person contact with MPX patients, via contaminated materials or by contact with infected animals. During pregnancy it can pass from mother to child or from the child at birth.

Supportive therapy is given to patients suffering from mpox in order to alleviate symptoms such as pain and fever. At the same time, close attention is paid by medical professionals for nutrition, hydration, skin care, prevention of secondary infections and possible treatment of co-infections inclusive of HIV.

Overview

M-POX is also know as Smallpox! Smallpox is an infectious disease that causes a painful rash, enlarged lymph nodes, fever, headache, muscle aches, back pain, and weakness. Most people make a full recovery, but some become seriously ill.

M-POX is caused by monkeypox virus (MPXV), an enveloped virus with double-stranded DNA in the genus Orthopoxvirus of the family Poxviridae, which includes Babolavirus, Cowpox virus, and vaccinia virus. The virus has two distinct clades: clade I (with subclades Ia and Ib) and clade II (with subclades IIa and IIb).

The global epidemic of clade IIb virus began in 2022 and continues to this day, including in African countries. In addition, clades Ia and Ib epidemics are increasing in the Democratic Republic of Congo and other African countries; as of August 2024, clades Ib has been detected outside of Africa.

The natural reservoir of the virus is unknown, but some small mammals, including squirrels and monkeys, are susceptible.

Transmission 

Mpox is transmitted from one person to another mainly through close contact with somebody who has mpox, even within families. Close contacts include skin-to-skin contact (like touching or sexual behavior) and direct contact of the mouth with the mouth or other parts of the skin (such as kissing). It can also involve being in a position where one is directly facing someone with mpox like talking or breathing close to each other, this can produce infectious respiratory droplets.

People who have sex with multiple partners are at greater risk of getting mpox.

Other modes of transmission include contamination from objects such as clothing or linen, needle injuries occurring in health care settings, or tattoo parlours in the community.

It can be passed on to the baby during pregnancy or childbirth. Infection with mpox while pregnant may harm the fetus or newborn infant and make them lose a pregnancy, give birth to stillborn baby, lead to death of the newborn child or complications for mother’s health.

Monkeypox is transmitted from animals to human beings. They become infected through bites, scratches or when they engage in activities like hunting, skinning, trapping, cooking, playing with carcasses and eating animals. For the monkeypox virus we are clueless about its animal reservoirs and it is currently being researched.

Further research is needed on the ways of spread during outbreaks in different settings and under different conditions.

Signs and symptoms

Signs and symptoms of smallpox usually begin within a week, but may begin 1 to 21 days after exposure. Typically, symptoms last 2-4 weeks, but may last longer if immunity is compromised.

Common Symptoms

• Rash

• Fever

• Thirst

• Headache

• Muscle pain

• Back pain

• Fatigue

• Swollen lymph nodes

In some people, the rash may appear first, while in others, fever, muscle aches, and sore throat may appear first.

The rash associated with chickenpox often begins on the face and spreads throughout the body, including the palms of the hands and soles of the feet. The rash may also appear on other areas of contact, such as the genitals. The rash begins as flat sores, which then change to blisters containing fluid that is itchy and painful to the touch. After healing, the rash dries and forms lesions that crust over and shed.

Some people may have only one or a few rashes, while others may have hundreds or more.

Soles of feet and palms of hands

Face, mouth, and throat

Groin or genital area

Anus

Some people also have inflammation of the rectum (proctitis), which can be painful, accompanied by dysuria, dysuria (dysuria), or swallowing pain.

Until all the sores heal and a new layer of skin forms, smallpox patients can pass the disease to others. Some infected people do not show symptoms at all. Although it is thought that it is possible to contract measles from someone who has no symptoms, there is little evidence to support this.

Such infected people include children, pregnant women, and people with weak immune systems, such as those with HIV, who are more likely to become seriously ill or die from complications of measles.

For example, the bacteria can infect the skin and form abscesses or cause extensive skin damage. Complications include pneumonia, corneal infection with loss of vision, painful swallowing or inability to swallow, vomiting or diarrhea causing dehydration and malnutrition, blood infection (septicemia), brain infection (encephalitis), heart infection (myocarditis), rectal infection (proctitis), male genital infection (balanitis), and urethritis (urethritis). Sometimes it can lead to death.

Diagnosis 

Differentiating smallpox from other infections and conditions that may be similar can be a daunting task. It is important to differentiate it from chickenpox, measles, bacterial skin infections, scabies, herpes, syphilis, other STIs and drug-induced allergies. Patients with chickenpox may also have other STIs such as syphilis or herpes. On the other hand, a child suspected of having chickenpox may actually have chickenpox. This is why testing is so important for prompt treatment and prevention of serious illness.

Detection of viral DNA by PCR is the gold standard for chickenpox detection in the laboratory. The best sample for diagnosis is taken directly from the rash. In the absence of skin lesions, pharyngeal or anal swabs can also be tested. However, blood samples should not be tested. This is because antibody detection methods cannot distinguish between different orthopoxviruses.

It may also be appropriate to test adults and older children suspected of having smallpox for HIV; diagnostic testing for other diseases such as VZV (varicella-zoster virus), syphilis and herpes simplex virus (HSV) should also be considered where possible.

Treatment and vaccination

The goals of smallpox treatment include care of the rash, pain management, and prevention of complications. Early supportive care is important to manage symptoms and avoid further problems.

Vaccination against measles helps prevent infection (pre-exposure prophylaxis). Vaccination of persons at high risk for chickenpox is recommended, especially during outbreaks.

Persons at high risk for chickenpox include

Medical and nursing personnel at risk of exposure;

People, including children, who live with or in close proximity to a varicella patient;

People with multiple sex partners (including men who have sex with men);

Sex workers and clients of any gender.

The vaccine can also be given after contact with a person who has had measles (post-exposure prophylaxis). In this case, the vaccine must be given within 4 days of contact. If no symptoms are present, the vaccine can be given for up to 14 days.

Several antiviral agents have been approved for emergency use in many countries and are being evaluated in clinical trials. To date, no antiviral therapy has been proven effective against smallpox. Continuing to evaluate therapies in robust clinical trials and optimizing supportive care for patients remains a priority.

HIV-infected and smallpox patients should continue antiretroviral therapy (ART).