The nurse was busy caring for patients in a small brick clinic when armed men ambushed the site and took her captive.
It was unclear on Thursday if any ransom was paid to release any of the missionaries.
The kidnapped Christians range in age from an 8-month-old baby to a 48 year old.
The gang leader threatened Haiti’s Prime Minister Ariel Henry and the chief of Haiti’s National Police.
Michel’s release was announced in a video posted on Facebook by his daughter on Tuesday.
Local unions and other organisations were planning to launch a strike Monday to protest the country's worsening security situation
A U.S. Christian aid organization on Sunday said a group of its missionaries had been kidnapped in Haiti.
According to the police, this gang has already killed 5 police officers.