Oct 21 (Reuters) - Abbott Laboratories posted a 28.3% rise in third-quarter profit on Wednesday, helped by strong sales of COVID-19 tests and strength in its nutrition and diabetes businesses.

The company's net earnings rose to $1.23 billion, or 69 cents per share, in the quarter ended Sept. 30, from $960 million, or 53 cents per share, a year earlier. (Reporting by Manojna Maddipatla and Trisha Roy in Bengaluru; Editing by Arun Koyyur)