Krdytkyu

Plastic is a huge problem in our lives. One of the ideas is to engineer plastic eating bacteria or fungi. Experiments already begun, and accidents already happen:

a team of international scientists illustrate how they created—by accident—a new enzyme capable of breaking down plastic bottles.

So let's assume microbe like that was engineered to just eat plastic like it eats sugars and other stuff. Then, containment broke in processing plants next to ten rivers that contribute the most to plastic problems:

1. Yangtze


2. Indus


3. Yellow


4. Hai


5. Nile


6. Ganges


7. Pearl


8. Amur


9. Niger


10. Mekong

How fast can we get this microbes all around the oceans, especially plastic deposits? They will be almost unchallenged on food, because hardly anything else in nature eats plastic, so all real life models look irrelevant to me. On the other hand, I'm not sure if I can just use speed of ocean currents - and if I can, simulating it is above my knowledge at the moment.

You can give this microbe any advantage needed, I want it everywhere as fast as possible to make my apocalypse sudden, and to make world unable to stop it.

Note:
This question does not touch things that are not relevant to rapidity of spreading. It avoids them on purpose, they will be worked upon in parts 2, 3 and possibly more. Now, if there is something missing about how fast could it spread in oceans, I'll be glad to work on this question. If it belongs to follow ups, please wait.

The debris generated by the tsunami hitting Japan in 2011 reached US West coast, thus crossed the Pacific Ocean, after few months.

This is your upper limit for the needed time. Add to this that, as opposed to solid debris, bacterial spores can be transported by wind or animals, and your diffusion time significantly shortens.

I.e. take an albatross resting in an infected plastic patch in the middle of the ocean, it will carry the spores hundreds of kilometers away in a matter of few days. And the more they are spread, the further they can spread.

The inventors of penicillin carried the mold out of Nazi territory by smearing it on their clothes.

If you want a quick dispersal, then consider human air travelers as your medium.

The initial release was tiny. It might not have spread at all beyond this city of bricks and concrete except for John Smith, in town for the day on business. A few tiny spores landed on his down jacket as he walked past the bland building housing the lab. They blossomed inconspicuously on the inside of the jacket's bottom hem and released more spores among the feathers.

When John stuffed his coat into the overhead bin before takeoff from Beijing, an almost invisible puff of spores wafted down the aisle and into an intake that would spread slow destruction throughout the plane. That plane eventually fell out of the sky, oil gummed and worthless, plastic components rotted out. But not before it delivered John to Amsterdam, where he was deplaned onto the apron. The day was cold, so he fluffed the jacket out, spreading spores on several nearby airport workers, before putting it on and boarding the shuttle to the terminal. It was several minutes before the shuttle was fully loaded. In the process, John was jostled several times as the other passengers crammed onto the bus, to the effect that no human left that shuttle without being thoroughly infected. They would fly on to Paris, Frankfurt, Jakarta, Sao Paulo... And John continued his journey too, heading first to Washington D.C.'s Dulles International, and then on to Atlanta, the busiest airport in the world.

These days any microbe can travel around the world in two days thanks to humans. It only take one human with plastic lunchbox, umbrella, wallet, anything really, to hop on a plane and be in another continent the same day. Once the microbes reach all major population centers in two, maybe three days, they will spread somewhat more slowly into the countryside on busses, telephone line insulation, newspaper wraps, but in couple of weeks at most, they are everywhere.