Inhuman Outbreak

The Inhuman Outbreak, also known as the Inhuman Epidemic, is the name given to the period following the contamination of the Earth's oceans with Terrigen. 

The contamination was caused deliberated by Jiaying, the leader of the Inhuman settlement of Afterlife, who released Afterlife's entire supply of Terrigen into the Atlantic ocean.

Drinking contaminated water or eating contaminated seafood can trigger Terrigenesis in humans with dormant Inhuman genes, resulting in a sudden explosion of Inhuman emergences in the months following the initial contamination.

The CDC initially classified the Inhuman Outbreak as an epidemic. However, they have since reversed this, following lobbying by NuHumans. 

Figures collected by the Advanced Threat Containment Unit suggest the rate of Inhuman emergence is slowing, possibly due to the majority of those with Inhuman ancestry having already undergone Terrigenesis. However, this may be in fact be a factor of increasing numbers of NuHumans concealing their status from the Government, either by masquerading as human, or emigrating to New Attilan.

Although affecting individuals world-wide, emergences are more common close to the original contamination point, meaning it has affected North America, especially the The United States of America,  more profoundly than other continents.