Influence of temperature and salinity on the viability and infectivity of Giardia lamblia and Cryptosporidia parvum.

The present work was designed to assess the effect of different degrees of temperature and salinity on the viability and infectivity of G. lamblia and C. parvum at different storage time. The results revealed that boiling of protozoa for one minute minimized their viability to less than 1% and rendered them non-infectious, while exposure to 4 degrees C and -4 degrees C up to seven days preserved their viability and infectivity. Whereas it was found that salinity was effective at high concentration (50 ppt) or for long storage time at lower concentrations.