my @filter_string_array = ('192\.168\.200\.|10\.10\.200',',SEVERE,');
...
my @local_filter_string_array = @filter_string_array;
my $first_filter_string = shift @local_filter_string_array;
my @output = grep {/$first_filter_string/} <$FILE>;
foreach my $filter_string (@local_filter_string_array){
	@output = grep {/$filter_string/} @output;
}