The Floating Dead: using flow cytometry to distinguish viable from non-viable Cryptosporidium oocysts

Featured student: Ashley Cooper
Supervisor: Dr. Brent Dixon

The contamination of drinking water with the transmissive stages of Cryptosporidium spp. and Giardia spp. has been well documented, especially in agricultural aquatic environments where faecal contamination of water sources with animal manure is common. Many of the techniques we commonly use to detect the presence of these stages (Cryptosporidium oocysts or Giardia cysts) do not tell us much about whether the organism is still alive. Cysts and oocysts are only a public health concern when they are infective and can result in disease, which requires the organisms to be viable. Thus, information on cyst and oocyst viability s of major importance to the development of microbial risk assessments, policies and programs. Ashley Cooper, a Masters student at the University of Ottawa, has been working in Dr. Brent Dixon’s lab on using flow cytometry to distinguish viable from non-viable cysts and oocysts. Read more.