Friends and famous fans of Madonna have sent messages of support to the star after she was hospitalized on Saturday.
Actors Evan Rachel Wood and Isla Fisher showed their support, as did singer The Weeknd.
Her manager said on Wednesday that she had developed a “serious antibacterial infection” and had been put in intensive care.
The 64-year-old singer was due to embark on a seven-month world tour but has now had to postpone it.
Celebrating 40 years in the industry, the tour was due to include a number of her greatest hits.
Madonna is believed to still be receiving treatment in a New York hospital but is no longer in intensive care.
