Sankar,
Mercury as your lagna lord is combust in 11th house giving you fear and is aspected by enemy Mars who is also lord of diseases. Also Moon-Venus in 12th house make you over-sensitive. Also Saturn as badhakesh aspecting your lagna as 8th and 9th house lord coupled with weak mercury (lagna lord) will keep your immune system weak.
Good thing is cuspal sublord of 1st house is Mercury, of 5th house of recovery and 11th house of gains is Jupiter. Both are posted in 11th house showing good health. Also 3rd lord Sun in 11th is good for courage and recovery
Rahu-Venus period from 19/3/2016 to 20/3/2019 will keep you worried as Venus is in 12th house and a soft planet but no major concern regarding health is foreseen. Ven-Sun from 20/3/2019 to 11/2/2020 might give some troubles as Sun has Rahu as sublord and Rah-Mars from 12/8/2021-31/82022 needs caution as Mars is in 8th house of sudden illness.
Wearing an emerald will help improve thinking/vitality and start of Jupiter Mahadasha from 31/8/2022 for 16 years will be great as Jupiter is natural benefic and placed in nakshatra of Venus with exalted Sun as sublord.
God bless,
Astrologer Deepak