Virus infections among young children--the first year of the INDIS study.

The frequencies of early childhood infections were studied in healthy children with increased genetic risk for type 1 diabetes participating in the ongoing prospective high intensive infection follow-up Study, INDIS, started in 2009 in Turku, Finland. Here the results obtained from 160 stool to 160 nasal swab specimens collected in parallel at times of infectious symptoms in 2009-2010 from 45 children at the age of 24 months or younger are reported. The specimens were analyzed for enteric (human enterovirus, norovirus, rotavirus, sapovirus, astrovirus) and respiratory RNA viruses (human enterovirus and rhinovirus) common in early childhood, respectively, using highly validated virus-specific real-time PCR methods. According to the results 96% of the children had at least one virus infection during the study period and one or several viral agents were detected in 76% of sample sets. The most prevalent viral agents were human rhinovirus, enterovirus, parechovirus, and norovirus (genotype GII) with positive specimens 57.5%, 28.8%, 19.4%, and 6.9%, respectively. Other intestinal viruses were found in less than 2% of stool specimens. Single infections covered 40.0% of the specimens while multiple infections with two or more infectious agents were detected in 36.3% of specimens and altogether 11 combinations of viruses were included in the mixed infections. Although human enterovirus is known to be a frequent finding in stool specimens, especially during early childhood, it was found in this study more frequently in nasal swab specimens. Whether this is true, more general, in countries with the high hygiene level remains to be shown.

Human rhinoviruses in INDIS-study material-evidence for recovery of viable rhinovirus from fecal specimens.

The significance of human rhinoviruses (HRV) as prevailing respiratory pathogens has sharpened during the recent years followed by implementation of molecular methods in detection. Rhinoviruses are detected exceedingly in hospitalized cases of respiratory infection with varying severity, in addition to being frequent in cases of common cold. The aim of this study was to evaluate occurrence of HRV in a prospective study material. The prospective INDIS material comprises nasopharyngeal (N=429) and fecal (N=425) specimens from children under 11 years of age collected during any clinical infection. Validated real-time RT-PCR assays were applied for the detection of HRV. HRV were detected numerously not only in the nasopharyngeal specimens, but a myriad also in fecal specimens, 236 (55.0%) and 149 (35.1%), respectively, fecal findings actually beyond anticipation. A total of 13 of HRV-positive fecal specimens were selected for genetic typing in the VP4/VP2 coding region. HRV-A strains were detected in seven specimens: HRV-A9, -A10, -A24, -A49, -A56 and -A82. HRV-B-strains were detected three times: HRV-B42 and -B79, and HRV-C twice: HRV-C12 and HRV-Cpat4. HRV-B42 also showed cytopathic effect in cell culture, confirmed by real-time RT-PCR and VP4/VP2 sequencing, suggesting presence of viable HRV in fecal specimens.

Effects of the viability of Lactobacillus rhamnosus GG on rotavirus infection in neonatal rats.

AIM: To study the effects of live and dead Lactobacillus rhamnosus GG (GG) on rotavirus infection in a neonatal rat model. METHODS: At the age of 2 d, suckling Lewis rat pups were supplemented with either live or dead GG and the treatment was continued daily throughout the experiment. At the age of 5 and 6 d the pups received oral rotavirus (RV) SA-11 strain. The pups were sacrificed at the age of 7 or 8 d by decapitation. The gastrointestinal tract was removed and macroscopic observations were done. The consistency of feces in the colon was classified using a four-tier system. RV was detected from the plasma, small intestine, colon and feces by real-time quantitative polymerase chain reaction (PCR). RESULTS: In this neonatal rat model, RV induced a mild-to-moderate diarrhea in all except one pup of the RV-inoculated rats. RV moderately reduced body weight development from day 6 onwards. On day 7, after 2 d of RV infection, live and dead GG groups gained significantly more weight than the RV group without probiotics [36% (P = 0.001) and 28% (P = 0.031), respectively]. In addition, when compared with the RV control group, both live and dead GG reduced the weight ratio of colon/animal body weight to the same level as in the healthy control group, with reductions of 22% (P = 0.002) and 28% (P < 0.001), respectively. Diarrhea increased moderately in both GG groups. However, the diarrhea incidence and severity in the GG groups were not statistically significantly different as compared with the RV control group. Moreover, observed diarrhea did not provoke weight loss or death. The RV control group had the largest amount of RV PCR-positive samples among the RV-infected groups, and the live GG group had the smallest amount. Rats receiving live GG had significantly less RV in the colon (P = 0.027) when compared with the RV control group. Live GG was also more effective over dead GG in reducing the quantity of RV from plasma (P = 0.047). CONCLUSION: Both live and dead GG have beneficial effects in RV infection. GG may increase RV clearance from the body and reduce colon swelling.

Early human enterovirus infections in healthy Swedish children participating in the PRODIA pilot study.

Human enteroviruses (HEV) are common, especially in childhood and during the enterovirus season, causing mainly asymptomatic infections but also mild and severe illnesses. Numerous studies have shown the association between HEV infections and type 1 diabetes. Here, the prevalence of HEV infections was studied in healthy Swedish children with increased HLA-associated risk for type 1 diabetes participating in the PRODIA pilot study in which children were randomized to receive probiotics or placebo during the first 6 months of life. Stool specimens collected from 197 children in every 3 months from the age of 3 to 24 months were screened for HEV using traditional viral culturing method and identified with reverse transcriptase polymerase chain reaction (RT-PCR) and sequencing of the partial VP1 coding part of the viral genome. Altogether 4.8% (52/1,094) of the specimens were HEV-positive and 22.3% (44/197) of the children excreted HEV during the follow-up. HEV-A and HEV-B were present in 2.1 and 2.7% of the specimens, respectively. HEV-C and HEV-D viruses were not detected. In total, 17 different HEV serotypes were detected and the most common findings were CV-A9 (13.5%), CV-A16 (11.5%), and CV-A2 (9.6%). The majority of the infections (92.3%) were during the enterovirus season extending from July to December. Probiotic treatment did not affect significantly the risk of HEV infections during the 2-year follow-up although a trend for transient decrease for HEV positivity (HEV-A and/or HEV-B) by the age of 12 months was observed in children who received probiotics [OR 0.40; 95% confidence interval 0.15 to 1.08; P-value 0.071, generalized estimating (GEE) analysis]. According to the results, HEV-A findings were nearly as common as HEV-B findings among the healthy children participating in this study. Also it was shown that serotypes belonging to HEV-A species can be detected by means of viral culturing.

Single treatment with ethanol hand rub is ineffective against human rhinovirus--hand washing with soap and water removes the virus efficiently.

Ethanol-containing hand rubs are used frequently as a substitute for hand washing with water and soap. However, not all viruses are inactivated by a short term rubbing with alcohol. The capacity of a single round of instructed and controlled hand cleaning with water and soap or ethanol-containing hand rub, respectively, was tested for removal of human rhinovirus administered onto the skin of healthy volunteers on the back of the hands. Hand washing with soap and water appeared to be much more efficient for removing rhinoviruses from skin than rubbing hands with an ethanol-containing disinfectant. After washing with soap and water the virus was detected in 3/9 (33.3%) test persons from the left hand and 1/9 (11.1%) cases from the right hand, whereas the virus was detected invariably by real-time RT-PCR from both hands after cleaning with alcohol hand rub (P-value <0.01). Both substances evaluated clinically were also tested in vitro for virucidal efficacy against Human rhinovirus2 (HRV2) using a standardized assay. Both tested substances were poor within the contact time used in the hand-cleaning test. In conclusion, thorough and conventional hand washing with water and soap can clean efficiently hands contaminated with the virus responsible for an extensive share of common cold episodes.

Enteric viral pathogens in children with inflammatory bowel disease.

The causes of exacerbations of inflammatory bowel disease (IBD) are unknown. The presence of RNA of an enterovirus, norovirus GI, norovirus GII, rotavirus, astrovirus, and sapovirus was sought in stool samples of 50 children (median age 12.9 years) undergoing gastrointestinal endoscopies for IBD or its exclusion (Crohn's disease n = 18, ulcerative colitis n = 13, indeterminate colitis n = 2, non-IBD n = 17). Viral RNA was found in three fecal samples (norovirus GII n = 2, sapovirus n = 1), all in children without IBD. Therefore, enteral viruses may play only a minor role in IBD.