The effects of extraction methods on the positivity rateof rotavirus infection

Abstract

The laboratory diagnosis of human rotavirus (HRV) based on many different methods. The latex agglutination test was the only method used in several hospitals in Iraq to detect HRV in stool samples. The frequency of positivity rate was proportional to the concentration of virions in the sample. The aim of this work was to study the efficiency of different extraction methods as filtration, sonication, ultracentrifugation and Freon-ether) on the results of Latex test also on the virus yield in tissue culture. The effectiveness was determined semi-quantitatively by LAT. All methods give statistically significant differences at p< 0.00 I except the low speed centrifugation gave differences at p<0.005. The results reveal that there are clear effects on positivity rate between the use of available methods and the sonication, ultracentrifugation and Freon -ether methods. The results of tissue culture revealed . that the cytopathic effects were visible when the virus preparation processed by the mentioned methods cause CPE after 12,24 and 48 hrs respectively in comparison with the available methods. The recommended methods for detection of RV particles from clinical specimens were sonication, ultracentrifugation and freon-ether.