1509
New drugs for neglected tropical diseases such as human African trypanosomiasis ( HAT ) are needed , yet drug discovery efforts are not often focused on this area due to cost .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None