What is Clade I Mpox, recently found in the US: Signs and symptoms to know

The dangerous and fast-spreading strain of Mpox Clade 1 has entered the USA. On Saturday, its first case was reported in California in a person with a travel history to Eastern Africa, where thousands of mpox cases driven by Clade I strain have been reported since January along with many deaths.
The person was diagnosed in San Mateo County, just south of San Francisco, and was isolated at home. Potential contacts of the patient are being reached out for further testing, by health officials.
Mpox is a zoonotic disease caused by Monkeypox virus belonging to the smallpox virus family. The disease can spread by a direct contact with an infected person or an animal. As per CDC, the virus can make entry through broken skin, respiratory tract, eyes, nose, or mouth. It has two clades and while Clade II was earlier detected in the US since 2022, the first case of Clade I has now been detected.

Why Clade I is concerning health authorities

Clade I is becoming a concern for health officials as it is a more severe strain of the Mpox with high transmission rates and more pronounced symptoms like intense skin rashes, larger lesions, and more severe lymphadenopathy or swollen lymph nodes.

Symptoms and severity

Not only the early symptoms of Clade 1 are severe, there is a higher rate of complications reported like encephalitis, pneumonia and respiratory distress, and secondary bacterial infections. This makes Clade 1 more deadly than Clade 2.

The spread of Clade 1B

Clade 1 is endemic to Central Africa. However, now a more concerning strain of mpox called clade 1b has been identified, which has higher transmissibility and more severe clinical outcomes.
Clade 1b that’s spreading currently in Africa and other countries has raised concern among health experts. The World Health Organisation (WHO) declared a public health emergency a few months back to tackle the threat. This new strain is believed to be more deadly than previous ones.
Clade 1’s route of transmission is through household contacts and both heterosexual and same-sex sexual contact in Central Africa.

Deadlier for children

This new strain is especially becoming a concern for children as they are experiencing more severe disease than adults, which was not the case with Clade 2.
Clade 1 is also more capable to kill compared to Clade II. Clade I has a worrying mortality rate of 1-10% compared to Clade 2’s 1-4% mortality rate.
CDC recommends JYNNEOS, a 2-dose vaccine developed to protect against mpox and smallpox. People need to get both the doses of the vaccine for the best protection against mpox.