sequelae

"Captain Palmer of the Norfolk had been suffering from a quartan ague and melancholia ever since the far South Sea: and since Butcher's medicine-chest had gone down with the ship, Stephen had prescribed for him, at first with considerable success. The ague and its sequelae had slowly yielded to Jesuits' bark and sassafras, but since their eastward rounding of the Horn the melancholia had grown steadily worse."
--Patrick O'Brian, The Reverse of the Medal, 51