Pulling a hash value in a data structure

[Freethinker0]

Sorry if the question is too rookie, I'm not a great, nor experienced coder. I am using the VirusTotal API to pull some info about some files. It returns a hash, which is too complicated for my feeble brain. Data Dumper shows the following data structure, which is in $res1. To be clear, the ultimate goal is to be able to pull out 'Eicar-Test-Signature':

$VAR1 = {
        'report' => [
                     '2011-01-25 10:30:50',
                     {
                       'AntiVir' => 'Eicar-Test-Signature',
                        ...
                     }
                    ]
        };

It looks to me like a hash within an array within a hash within a hash. If I do print ($res1->{'report'}[0]); it returns '2011-01-25 10:30:50'. So far so good. I thought from here I need to do is change the code to print ($res1->{'report'}[0]->{'AntiVir'}); to get the key value of 'Eicar-Test-Signature'. Instead it returns nothing. I know I am close, but after a few hours on this, I am turning to you guys. Thanks much.