Mystery surrounding Senator Mitch McConnell's health is deepening as the US Congress prepares to return from recess next week. McConnell, 84, has not been seen in public since he was admitted to hospital in the Washington area on 14 June. Nearly a month later, the Kentucky Republican's office has released only sparse updates, saying he is "continuing to improve" and remains engaged with Senate business, while refusing to disclose the nature of his illness or explain why he remains hospitalised.