Do you ask about the disease "Leptospirosis" or the agent "Leptospira spp."?
The clinical aspects of the disease range from mild type to severe type and from acute to chronic leptospirosis. Clinical aspects are dependant on the species (human, domestic animals, wildlife, rodents...).
The aethiological agent has diverse phenotypic and genotypic properties. The serovar is the serologically least divisible recognized type. Also, genomic classification allows genonommospecies differentiation. The TSCL publish periodically the serovar list.
Classification among Leptospira genus is a complex item. Depend on your specif interest there are diverse available information (OMS or ILS web site...)