Aug 25 (Reuters) - American Airlines (AAL.O) said on Wednesday its August revenue was trending below the U.S. carrier"s internal forecast as a recent uptick in COVID-19 cases led to some softness in bookings. American"s Chief Revenue Officer Vasu Raja, speaking at the Raymond James industrials conference, said the airline was also experiencing a rise in cancellations. COVID-19 cases, driven by the highly infectious Delta variant, have surged in parts of the United States with lower vaccination levels. However, Raja added that the company"s booked business for the holidays remained "incredibly strong". The carrier expects business demand to likely come back in the transatlantic and Latin American regions, given their proximity to the United States. American shares have risen 26.6% so far this year. The U.S. could get COVID-19 under control by early next year if vaccinations ramp up, the nation"s top infectious disease expert, Dr. Anthony Fauci, said on Tuesday, as Pfizer won full FDA approval for its shot, with more potential approvals coming in the weeks ahead. read more