Dim strWho As String
Dim strSubject As String
Dim objNewMail As Outlook.MailItem

Set objNewMail = Application.CreateItem(olMailItem)

strWho = objMail.To
strSubject = objMail.Subject

With objNewMail
    .To = strWho
    .BCC = "mail2,mail3,mail4,mail5"
    .Subject = strSubject
    .Display
    .Send
End With

"person1@email.com;person2@email.com"

Dim strWho As String
Dim strSubject As String
Dim objNewMail As Outlook.MailItem
Dim bccMails As String

Set objNewMail = Application.CreateItem(olMailItem)

strWho = objMail.To
strSubject = objMail.Subject
bccMails = objMail.BCC

With objNewMail
    .To = strWho
    .BCC = bccMails
    .Subject = strSubject
    .Display
    .Send
End With

Dim bccMails As String
bccMails = InputBox("Please insert .bcc email addresses, separated by semicolons", "Email Address", "person1@email.com;person2@email.com")