Nitrosomonas oligotropha

Norovirus Genogroups I and II

Novel Coronavirus Strain 2019-nCoV

O'nyong-nyong Virus

Orientia tsutsugamushi

Oxalobacter formigenes

Parechovirus

Pasteurella multocida

Pichia kudriavzevii

Plasmodium falciparum

Plasmodium knowlesi

Plasmodium malariae