#!/usr/bin/perl
use strict;
use warnings;

my $first_line = <DATA>;
chomp $first_line;
$first_line =~ s/,/chr(31)/eg;
print $first_line, chr(30);
while (<DATA>) {
    chomp;
    my @fields = split /,"|",/;
    $fields[2] =~ s/,/chr(31)/eg;
    print join chr(31), @fields, chr(30);
}

__DATA__
Country,Name,Address,Age
Andorra,"Aileen, Daquan, Hammett, Malachi",17014,69
Solomon Islands,"Cyrus, Giacomo, Gretchen, Curran",76935,26
Czech Republic,"Briar, Larissa, Sybil, Colin",29565,88
(...)