has there been any microbiology test conducted on patient 31615 in 05/this year?
select count(*)>0 from microbiologyevents where microbiologyevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 31615 ) and datetime(microbiologyevents.charttime,'start of year') = datetime(current_time,'start of year','-0 year') and strftime('%m',microbiologyevents.charttime) = '05'