Sir My Docter Has Fever From Last Thrusday;her Platelets. Becomes

Sir my docter has fever from last thrusday;her platelets. Becomes down till 120lakb first her denu test become negative anna thyphoid became positive but today I again tested. Her platelets and thyphoid yes then thyphoid become negative.I concern. With other doctor he said thuphoid comes positive till six months.the first test may be wrong please give me advise about it.