How many {symptoms} are for {malaria} ?
What symptoms does malaria have?
What are the symptoms of malaria?
SELECT ( COUNT ( ?t ) AS ?o ) { resource:malaria property:symptoms ?t }
SELECT (COUNT(?obj) AS ?objs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q12156> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P780> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
} 

SELECT (COUNT(?obj) AS ?value ) { wd:Q12156 wdt:P780 ?obj }
8