According to

80% of all infections are transmitted by hands.

According to the CDC scientists estimate that people who are not washing their hands often or well enough are spreading germs. Harmful germs can live on almost everything from doorknobs to animals to food.

See too Fear of Germs Threatening the Handshake.

So, shouldn’t the US adopt the custom of bowing too?

Presumably, fewer people in Japan get sick, thanks to their custom of bowing rather than shaking hands. But I am unaware of studies that validate this claim.

Of course, Japan is much more crowded than the US, on average, with commuters packed into crowded trains and subways.  Also, I recall that Japanese people often wear white surgical masks in public when they have a cold or flu.  But if you factor in those effects, is there less contagion in Japan thanks to the custom of bowing?

Aside from the benefits of fewer sick people, it would be a lot of fun watching Americans learn to bow.  That’s my real reason for proposing this!

Let's learn to bow. Shaking hands spreads germs.