The Epidemiological Study Of Viral Diarrhea In Guangzhou

MethodsTen stool specimens and the feature of case history including names,gender,age,disease time,dwell time,clinical symptoms,stools routine examination results,doubtful impurity dietary history and diarrhea exposure history ,were collected in children with watery diarrhea in Guangzhou Women and Children Medical Care Center every Tuesday and Friday from August 2008 to July 2009. then real-time fluorescence quantitative PCR was used to detect HRV, NORV, EADV, ASTV, SPAV. five positive samples were randomly selected to RT-PCR,clone,and sequenced,eventually the genomic nucleotide sequences were analyzed with principle of statistics.Results1. Out of the 985 specimens tested, 452 showed positive for at least one kind of Virus, mixed infection accounts for 22.3%(101/452) including2 specimens of 3 virus , the annual detection rate of HRV, NORV, EAdV, ASTV, SPAV were 27.9% (275/985), 13.7 % (135/985), 8.8% (87/985), 4.9% (49/985), 1.0%. (10/985).2. The monthly rate of virus were all more than 35% except April. Significantly increase began in August and the peak appeared in November (P<0.05 compared with the first eight months of the year). The monthly rate of HRV1-6 is about 20%.Significant increase also began in August and the peak appeared in November (P<0.01 compared with the first eight months of the year).The highest detection rate of NORV, EADV, ASTV and SPAV developed among October to December, but there is no significant difference compared with other months.3. The randomly sequencing results of 5 kinds of virus showed : HRV :G3 type50%(5/10),G1 type40%,G2 type 10%(1/10). 2.NORV:GII-4 type 80%(8/10), GII-3 type20%(2/10).3. EADV:Ad41 80%(8/10),Ad40 20%(2/10),4. ASTV:ASTV-1 80%(9/10),ASTV-4 10%(2/10),5.SPAV:GI-1 90%(9/10),GIV 10%(1/10)4. Viral diarrhea mainly occurred in infants under 2 years,the average age for HRV was(12.06±8.19) months,EADV(12.33±7.94)months,NORV(11.23±6.27)months and ASTV(11.02±8.74)months.5. The main symptoms of viral diarrhea were watery stools(88.9%), accompanying with vomiting(75.2%),fever(65.2%).There were no significant difference among the three symptoms in the study(p>0.05).Conclusion1.Viral diarrhea is frequently in infant acute diarrhea in Guangzhou , pathogens are HRV, NORV, EADV, ASTV, SPAV, HRV is the most important .2. October to December is the peak of viral diarrhea, infants below 2 are the main infected population, HRV has obvious seasonal specificities.3. Different virus have its own predominant strain. The predominant strain of RV is G3, while NORV is GII-4,EADV is type 41, ASTV is ASTV-1, SPAV is GI-1.4. The main symptoms of virus diarrhea mainly manifested as watery stool, accompanying with vomiting and fever, combined infection may not aggravate the symptoms.