Washington, Nov 1 (IANS): A Stanford University study has revealed that 18 re-election campaign rallies of US President Donald Trump have resulted in more than 30,000 coroanvirus cases.

According to the study, the rallies were held between June 20 and September 23, of which only three took place indoors, The Hill news website reported.

The authors of the study said that the rallies increased subsequent confirmed cases by over 250 infections per 100,000 residents.

They found that the events also likely resulted in over 700 deaths, but the fatalitie were "not necessarily among attendees".

"Our analysis strongly supports the warnings and recommendations of public health officials concerning the risk of Covid-19 transmission at large group gatherings, particularly when the degree of compliance with guidelines concerning the use of masks and social distancing is low," The Hill news website quoted the authors as saying in the study.

"The communities in which Trump rallies took place paid a high price in terms of disease and death."

But in reaction to the development, Trump campaign deputy national press secretary Courtney Parella told The Hill news website on Saturday that, "Americans have the right to gather under the First Amendment to hear from the President of the US".

"We take strong precautions for our campaign events, requiring every attendee to have their temperature checked, providing masks, they're instructed to wear, and ensuring access to plenty of hand sanitizer.

"We also have signs at our events instructing attendees to wear their masks," she added.

Also in a statement to The Hill news website, Andrew Bates, the spokesman for Demmocratic presidential nomine Joe Biden, said that Trump is "costing hundreds of lives and sparking thousands of cases with super spreader rallies that only serve his own ego".

On Friday, the US reported 97,080 new Covid-19 cases, the highest single-day spike since the pandemic began earlier this year.

As of Sunday, the US, currently the worst-hit country, accounted for a total of 9,116,186 cases and 230,345 deaths.