The ATK of a non Machine-Type monster equipped with this card is decreased by 300 points at each of its Standby Phases.
Rulings
Netrep Rulings
The lowering of ATK and DEF by the effect of "Germ Infection" is stopped when the ATK reaches 0. However, the effect of "Germ Infection" does not end and may continue if the monster's ATK is raised above 0 by some other effect.
Netrep Q&As
Q: Does โGerm Infection'sโ decrease continue to accumulate even after the ATK has reached 0? A: The decrease in ATK will continue to accumulate. So, if I have a "White Magicial Hat" equipped with "Germ Infection" for 4 Standby Phases, it would be receiving -1200 to its ATK. (I would treat its ATK as 0, since 1000 - 1200 = -200) If I were to equip an "Axe of Despair" to that same "White Magicial Hat," its ATK would be 1000 + 1000 [Axe] - 1200 [Germ Infection] = 800 ATK. Curtis Schultz, 02/24/2004