foreach my $test (@test) {

   my ($condition,$persons) = ($2,$3) if($test =~ /(positive for )?(\w+).*\((.*)\)/i); # $1 capture will either be "positive for" or empty
   $persons =~ s/\s+//g; # omit spaces
   $persons =~ s/,/;/g;  # changes any commas to semi-colons to have a common separator

   my @persons = split /;/, $persons;
   foreach my $person (@persons) {
      print "$person\t|| $condition\n";
   }
}