Grabbing all and sending as one

Evening all,

I'm trying to get a script then will run on a CRON job at some point. it works as you see it, however when more than one server is down it sends a new email for every server, how would i go about getting it to grab all down servers and sending in just 1 email?

Thanks guys! (code below).

<?
$hosts = array( 
array ( "hostdescription" => "B1", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "B2", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "BB1","hostaddress" => "IP HIDDEN" ), 
array ( "hostdescription" => "BB2", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "BB3", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "BBB1", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "BBB2", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "BBBB1", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "BBBB2", "hostaddress" => "IP HIDDEN" ),
array ( "hostdescription" => "BBBB3", "hostaddress" => "IP HIDDEN" ) );  
$pingcount = 1;  
foreach ($hosts as $host){  
$hostdescription = $host["hostdescription"];  
$hostaddress = $host["hostaddress"];  
exec("ping -c $pingcount -w $pingcount $hostaddress", $pingoutput, $Spingstatuscode);  
if($Spingstatuscode === 0){ 
echo("$hostdescription ($hostaddress) is Up <BR>"); }else{ 
echo("$hostdescription ($hostaddress) is Down <BR>"); 
$to = "EMAIL HIDDEN";
$subject = "SERVER DOWN: $hostdescription"; 
$message = "ATTENTION: $hostdescription is currently down please investigate"; 
$headers .= "From: EMAIL HIDDEN\r\n";
$mail_sent = @mail( $to, $subject, $message, $headers );
} }
?>