Matsya Purana — Characteristics of Dvāpara and Kali Yugas
तेषां विपर्ययोत्पन्ना भवन्ति द्वापरे पुनः अदृष्टिर्मरणं चैव तथैव व्याध्युपद्रवाः //
teṣāṃ viparyayotpannā bhavanti dvāpare punaḥ adṛṣṭirmaraṇaṃ caiva tathaiva vyādhyupadravāḥ //
For them, in the Dvāpara age, reversals and perversions arise again—loss of right discernment, death, and likewise the assaults of diseases and calamities.
It does not describe Pralaya directly; it describes yuga-based degeneration—how, in Dvāpara, disorder and suffering manifest as loss of right vision, increased mortality, and disease.
By warning that disease and calamity intensify in Dvāpara, it implies stronger royal and household duties: protection of subjects, public health measures, charity, ritual observances, and adherence to dharma to counter social and bodily decline.
No explicit Vāstu or iconographic rule is stated; however, the verse supports the ritual logic found elsewhere in the Matsya Purana—temple worship, purification rites, and dharmic observances are prescribed as stabilizing responses to yuga-born afflictions.