Bear in mind that when people are talking about finding SARS-CoV2 "surviving" on surfaces many hours or days later, they're not necessarily talking about the virus in a viable (and thus harmful) form. Usually they're finding viral particles; basically finding the viruses in non-viable and harmless forms because they've been outside of a living host for too long. The viruses have broken down to the point that they're no longer able to attach onto host cells.

A research study published on 17/3/20* found that while SARS-CoV2 can remain viable in aerosol form for up to 3 hours (another reason why I wear a mask!❋) and on surfaces for up to 72 hours (wash your hands!), no viable coronaviruses were detected on metal surfaces after four hours and twenty-four hours on cardboard. So in terms of toy packaging, at most the virus will only remain in viable form on the cardboard for up to 1 day, after when it breaks down into harmless viral particles.

Having said that, if you're still concerned just go ahead and disinfect the box before opening it. That's what I did when I picked up Gulf today. I literally took a can of spray-on disinfectant with me to the shops, and straight after purchasing the toy I stepped outside of EB, put the toy down on a nearby table, then sprayed it with disinfectant (and sanitised my hands for good measure). The EB staff also offered me a plastic bag (so I could've carried it out without touching it if I really wanted to).

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*17/3/2020 research study, New England Journal of Medicine by the National Institute of Allergy and Infectious Diseases and Princeton University
❋That and because I'm always touching my face, so wearing a mask provides a physical barrier between my hands in face. But there are some grubs out there who still don't cover their freaking mouths when they cough