Mpox (Monkeypox) | Transmission, Pathophysiology, Signs & Symptoms, Diagnosis, Treatment

Summary

This video covers Mpox (previously known as Monkeypox), a viral disease caused by the Mpox virus, part of the Orthopoxvirus genus, similar to smallpox but less severe. It discusses the virus's zoonotic origins, its transmission from animals to humans, and the 2022 outbreak that led to global human-to-human transmission, primarily through skin contact. Symptoms include a flu-like prodromal stage followed by a distinctive rash. Diagnosis is through lab tests, and treatment focuses on supportive care, with antivirals in severe cases. The video also touches on the impact of smallpox vaccination and the risks for immunocompromised individuals.

Takeaways

• 🦠 Mpox, formerly known as monkeypox, is caused by the Mpox virus, which is related to the smallpox virus but less severe and less infectious.
• 🐒 The virus is zoonotic, meaning it spreads from animals to humans. Humans are incidental hosts, and African rodents are the primary reservoirs.
• 🌍 The first known case was in lab monkeys in 1959, but the first human case was reported in Zaire (now the Democratic Republic of Congo) in 1970.
• 📈 Mpox cases increased after the discontinuation of the smallpox vaccine, which helped protect against the virus. An outbreak occurred in 2022 with over 30,000 cases in the US by early 2023.
• 🤝 The virus spreads through respiratory droplets, prolonged close contact, direct contact with infected animals or humans, and contaminated surfaces. Skin-to-skin contact, particularly sexual transmission, has driven recent outbreaks.
• 🧬 The virus enters the body through mucous membranes or the skin, replicates in lymph nodes, and eventually enters the bloodstream, causing a flu-like illness before a rash appears.
• 💉 The incubation period ranges from 4 to 21 days, with symptoms like fever, chills, swollen lymph nodes, and a rash that develops in stages over 14 to 21 days.
• 🧪 Diagnosis can be made through lab tests like PCR, viral culture, or electron microscopy. In some cases, clinical symptoms and exposure history are enough to diagnose.
• 🩺 Treatment is mostly supportive as the infection is self-limiting, though antiviral therapies like tecoviromat may be used in severe cases or for immunocompromised patients.
• ⚠️ Mpox can lead to complications like secondary bacterial infections, respiratory distress, eye infections, and encephalitis, with higher mortality risks in immunocompromised individuals.

Q & A

What is mpox, and how is it related to monkeypox?

Mpox, formerly known as monkeypox, is a viral infection caused by the mpox virus, which belongs to the genus Orthopoxvirus, the same genus as smallpox. However, mpox is less severe and less infectious than smallpox.

How is mpox transmitted between humans?

Mpox can be transmitted between humans primarily through close, prolonged face-to-face contact via respiratory droplets, direct skin-to-skin contact, sexual transmission, or contact with contaminated objects, such as clothing or furniture. Vertical transmission from a pregnant person to the fetus is also possible.

What are the primary animal hosts of the mpox virus?

The mpox virus is zoonotic, meaning it is spread from animals to humans. Its natural reservoirs are African rodents, including species like Gambian rats. Monkeys and humans are incidental hosts, meaning they are not the virus's intended hosts.

When was the mpox virus first discovered, and how did it get its name?

The mpox virus was first isolated in lab monkeys in Denmark in 1959, which is how it earned the name 'monkeypox.' The first human case was reported in Zaire (modern-day Democratic Republic of Congo) in 1970.

What are the symptoms of mpox, and how does the infection progress?

Mpox begins with a flu-like prodromal stage, including fever, chills, headaches, muscle aches, and swollen lymph nodes. This is followed by a rash that begins on the mouth or face and spreads to other parts of the body, including the palms and soles. The rash progresses from macules and papules to pustules, which eventually scab and heal over several weeks.

How long is the incubation period for mpox, and what does this period involve?

The incubation period for mpox ranges from 4 to 21 days, with an average of 12 days. During this time, the virus enters through mucous membranes or skin, spreads to local lymph nodes, multiplies, and eventually enters the bloodstream.

What factors contributed to the increased prevalence of mpox in recent years?

The decline in the use of the smallpox vaccine, which offers cross-protection against mpox, has led to an increase in cases. The 2022 outbreak was largely driven by human-to-human transmission, especially through sexual contact.

What complications can arise from mpox infections?

Complications of mpox can include secondary bacterial infections, respiratory distress, eye issues like keratitis, and, in severe cases, septicemia or encephalitis, especially in immunocompromised individuals.

How is mpox diagnosed by clinicians?

Mpox is diagnosed through laboratory methods such as isolating the virus, PCR testing, electron microscopy, and blood work. A diagnosis can also be made if symptoms appear within 21 days of exposure to a confirmed case.

What treatments are available for mpox infections?

Most mpox cases resolve on their own with supportive treatment. In severe cases, antiviral therapies such as tecovirimat (Tpoxx) may be used, particularly for immunocompromised patients or those with ocular symptoms.