How many {afflicts} are for {lead poisoning} ?
Lead poisoning is the cause of how many illnesses?
How many illnesses are from lead poisoning?
SELECT ( COUNT ( ?f ) AS ?p ) { resource:lead_poisoning property:afflicts ?f }
SELECT (COUNT(?obj) AS ?objs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q110315> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P689> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
} 

SELECT (COUNT(?obj) AS ?value ) { wd:Q110315 wdt:P689 ?obj }
7