Context: The United States has reported the first suspected local transmission of the Clade I Mpox strain, with no international travel link identified. The confirmation raises public health concerns, as Clade I is considered more virulent than the Clade II strain that caused the global 2022 outbreak.
This incident marks a potential shift in the epidemiology of Mpox, signaling community-level spread within North America.
About Mpox
- Causative Agent: Mpox (formerly known as Monkeypox) is a zoonotic viral infection caused by the Monkeypox virus (MPXV), belonging to the Orthopoxvirus genus, closely related to smallpox.
- Transmission: Occurs via contact with infectious lesions, body fluids, contaminated materials, or respiratory droplets from infected individuals or animals.
- Symptoms: Fever, headache, swollen lymph nodes, muscle pain, and characteristic painful skin lesions (often on face, hands, and genital areas).
- Severity: Children, pregnant women, and immunocompromised individuals are more prone to complications such as secondary infections and pneumonia.
Clades of Mpox
- Clade I:
- Geographic Origin: Central Africa (mainly Congo Basin).
- Fatality Rate: 1–10%.
- Severity: More virulent and transmissible.
- Clade II (A & B):
- Origin: West Africa.
- Fatality Rate: <1–4%.
- Responsible for 2022 Global Outbreak.
Treatment and Prevention
- Treatment: No specific antiviral cure exists. However, Tecovirimat (TPOXX) and Brincidofovir are used under emergency authorisations to manage severe infections.
- Vaccination:
- Jynneos (Imvamune/Imvanex) by Bavarian Nordic is the approved vaccine offering cross-protection against both Mpox clades.
- Target groups include healthcare workers, laboratory staff, and close contacts of confirmed cases.
- Public Health Response: Enhanced surveillance, contact tracing, and isolation remain critical for containment.
India’s Status
Between December 2024 and March 2025, India recorded 10 confirmed cases of Clade 1b Mpox, all traced to travel from Gulf countries.
There has been no community transmission reported domestically so far. India continues to follow WHO-recommended surveillance and vaccination guidelines under the National Centre for Disease Control (NCDC).
Significance
- The local transmission of Clade I indicates the virus’s capacity to adapt and spread beyond endemic regions.
- It underscores the need for genomic monitoring, rapid diagnostics, and international cooperation under the International Health Regulations (IHR) framework.