The 29-year-old claimed on Twitter that neither Boro nor his national football association in Sierra Leone had offered to help him.
"So as u may or may not know by now I play for Middlesbrough FC & represent my nation Sierra Leone. I have had Malaria for a week now. Not fun," he wrote yesterday.
"Now I am feeling better it's time to say: 'Thank you MFC & SLFA for doing NOTHING.'"
Kamara is in Kansas where he used to play for Sporting Kansas City, who he said cared for him.
The striker made 25 appearances for Boro in the Championship last year, scoring four goals.