JMM founder Shibu Soren died on August 4 while undergoing treatment at Sir Ganga Ram Hospital in Delhi.
The JMM patriarch, who was a towering figure in Jharkhand's political landscape, was admitted to the Sri Ganga Ram Hospital in the national capital since last month with a kidney-related issue.
Shibu Soren, has been receiving regular treatment at the hospital for an extended period.
Champai Soren, who is set to join the BJP on August 30, also stepped down as an MLA and a minister in the Jharkhand Cabinet.
The Election Commission has taken cognisance of a complaint against Soren and the high court has issued a notice to him, but legal experts said he is unlikely to face disqualification as a member of the state assembly
Samples of 29 people in Shibu Soren's household were collected for examination, of which seven were found to have contracted the disease
In the wake of a political turmoil created after the Jharkhand Mukti Morcha (JMM) withdrew its support from the Bharatiya Janata Party-led government in the state, the JMM leaders met the state governor to explore scenarios for forming a new government.