TABLE 1.

Infectivity of C. parvum oocysts stored at room temperature and 4°C

Length of time (wk) at temp	Mouse infectivity (% infected)	Fecal oocyst scorea
Room temp
0	100	2–3
5	80	2
11	60	2
15	20	1
20	0	0
4°C
0	100	2–3
11	100	1–3
20	100	1–3
29	100	1–3
39	100	1–2

^aFor explanation of oocyst score, see reference 27.