Your magical contagions become viral and more dangerous, improving in the following ways.
Cursed Infection
Choose one ability when a creature gains the Poisoned condition of your Infection. While it has the condition, it has Disadvantage with ability checks and saving throws made with that ability.
Viral Infection
A target of your Infection spreads disease in a 5-foot Emanation while it has the Poisoned condition. Whenever the Emanation enters the space of a creature you can see and whenever a creature you can see enters the Emanation or ends its turn there, you can force that creature to make a Constitution saving throw against your Infection as well. On a failed save, the creature also gains the Poisoned condition and magical contagion of Infection and spreads disease in a 5-foot Emanation.