Deputy Health Minister Ali Reza Raesian announced the guidelines, which include social distaining, to prevent further spread of the coronavirus.
All of those attending the rituals must wear face masks and the elderly and those suffering from chronic illnesses are urged to observe the rituals at home.
Also, organizing mourning programs in open spaces is a priority.
Shia Muslims around the world mourn the martyrdom of Imam Hussein (AS), the Sayyid-ul-Shuhada (master of martyrs), in Muharram (begins on August 21 this year).
The third Shia Imam (AS) and a small group of his followers and family members were martyred by the tyrant of his time - Yazid Bin Moaweya, in the battle of Karbala on the tenth day of Muharram (known as Ashura) in the year 680 AD.
The coronavirus outbreak that originated in Wuhan, China, has infected over 18.4 million people around the world and killed more than 698,000.
The outbreak has had a major impact on global sporting, cultural, religious and political events, with a host of events canceled or postponed.