Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 5 · Portents, Comets
ग्रहचारः केतवश्च
दुर्भिक्षं क्षुद्भयं रोगान्करोति क्षितिनंदनः ।अष्टादशे सप्तदशे तद्वक्रं मुशलाह्वयम् ॥ ३१ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 56, verse 31.
Mars then brings famine, fear of hunger and illness. If it turns back in the 18th or 17th nakshatra (star), that turning back is called Mushala.
Simple meaning: Mars turning back in the 15th or 16th star can bring famine, hunger and illness.
Classical view, not medical advice.
दुर्भिक्षं धनधान्यादिनाशने भयकृत्सदा ।
A Mushala turn tends to bring famine and fear of losing wealth and grain.
अस्तगश्चतुरास्यार्क्षे लोकत्रयविनाशकृत् ।
Mars setting in Rohini may bring wide harm. Risen in Shravana or Pushya it can bring loss of cows and horses.
यद्दिग्गोऽभ्युदितो भौमस्तद्दिग्भूपभयप्रदः ।
Mars rising in a direction brings fear to that direction's king.