Under the RNTCP, sputum culture for MDR TB is to be examined for at least:: (A) 4 weeks, (B) 8 weeks, (C) 10 weeks, (D) 12 weeks
Answer is B. All cultures should be examined 48-72 hours after inoculation to detect gross contaminants. Thereafter cultures are examined weekly, up to 8 weeks on a specified day of the week. Ref: