Viral Gastroenteritis in Children in Colorado 2006-2009 Christina M. Osborne, BA1; Aaron C. Montano, BS; Christine Robinson, PhD3; Stacy Schultz-Cherry, PhD4; Samuel R. Dominguez, MD/PhD1,2

1University of Colorado School of Medicine; 2Department of Pediatrics, Section of Infectious Diseases; 3Department of Pathology, Children’s Hospital Colorado;4 St. Jude Children’s Research Hospital, Department of Infectious Diseases

Abstract

Background

References 1.UnicefWho, “Diarrhoea: Why Children Are Still Dying and What Can Be Done,” Www.Unicef.org (2009). 2. Parashar Umesh D, et al. Harrison's Principles of Internal Medicine, 18e, Chapter 190 3. Harris, J.B. et al. New England Journal of Medicine. 2011. Vol. 364 Issue 25, p. 2452-2461. 4. Claas E. et al J. Clin. Microbiol. 2005 Apr; 43(4) 1738-44 5. Dominguez SR et al. J. Med. Virol. 2009 September 81(9) 1597-1604 6. Colomba C et al. The Lancet. 2006 vol. 25 (9) 570-575 7. Feeney SA et al J. Med. Virol. 2011 83 (9) 1650-1656. 8. Hall Aron. Emerg. Infect. Dis. 2011.vol. 17 (8) 1381-1388. 9. Monteiro L et al. J. Clin. Microbiol. April 1997. 995-998 10. Dey SK et al. Epidem. Infect. 2012 vol. 140 (1) p 74-77

Background: Acute gastroenteritis accounts for a significant burden of medically attended illness in children under the age of five. Methods: Four multiplex RT-PCR assays were used to determine the incidence of seven viral agents (adenovirus, astrovirus, coronavirus, norovirus GI and GII, rotavirus, and sapovirus) in stool samples submitted for viral electron microscopy (EM) to the Children’s Hospital Colorado during a 34-month period (2006-2009). Results: Of 1587 stool samples submitted, 1082 (68%) were available for this study. 940 samples were from pediatric patients (median age = 2.97 years, 55% male). 132 were from adult patients submitted from an outside hospital during a 3-month period. Of pediatric samples, we detected viral RNA/DNA in 245 (28%) with 28 (3.1%) samples containing RNA/DNA for more than one virus. Adenovirus was detected in 95 (10%) (10%) samples, astrovirus in 33 (4%), norovirus GI in 8 (0.9%), norovirus GII in 90 (10%), rotavirus in 49 (5.2%), sapovirus in 2 (0.2%), and coronaviruses in 0 samples. Multiple samples from the same immunocompromised patients demonstrated shedding of norovirus for 32 weeks, astrovirus for 12 weeks, and adenovirus for 5 weeks. Of adult samples, 49 (37%) were positive for norovirus GII. When comparing diagnostic sensitivity, RT-PCR detected 89 of 102 (87%) total adenovirus-positive samples vs. 25 (25%) detected by EM; 155 of 164 (95%) total astrovirus/norovirus-positive samples vs. 23 (14%) by EM. However, rotavirus RT-PCR detected 50 of 84 (60%) total rotavirus-positive samples vs. 55 (66%) by EM. Conclusion: Noroviruses and adenoviruses are common causes of gastroenteritis in children. Immunocompromised patients can be infected with multiple viruses and shed viruses in their stools for prolonged periods. Our data support the use and superiority of RT-PCR compared to electron microscopy for the diagnosis of viral gastroenteritis. Continued targeted efforts at novel prevention and therapeutic interventions for noroviruses are warranted.

•  Fecal specimens collected at Children’s Hospital Colorado between 2006 and 2009 from inpatients and outpatients with symptoms of gastroenteritis were analyzed using electron microscopy and multiplex real-time PCR. •  Separate multiplex assays screened for adenovirus and rotavirus, astrovirus and sapovirus, norovirus group I and group II, and coronavirus. •  Samples were evaluated for possible PCR inhibitors by PCR with known quantity of pandemic 2009 H1N1 influenza A RNA. • Retrospective chart review was performed.

Diarrheal Illness •  Common illness with 2.5 billion cases per year

in children < 5 years of age.1 •  Responsible for 10-12% of all hospitalizations in

industrialized countries.2

•  Children in developing countries have >3 episodes of diarrhea annually (median) and it causes 1.6-2.1 million deaths annually.3

•  2nd leading cause of death among children outside neonatal period in the world

Study Design This retrospective study looks at the prevalence of rotavirus, adenovirus, astrovirus, norovirus,

sapovirus, and coronavirus (outlined in yellow), all known viral etiologic agents of gastroenteritis.

Methods

Contact Information/Disclosures

Sample Characteristics

Table 2: Demographics of pediatric stool samples submitted for Testing by EM and stored for this study.

Epidemiology Data

2006 2007 2008 2009 2006 2007 2008 2009

2006 2007 2008 2009

Rotavirus Norovirus GII

2006 2007 2008 2009

Adenovirus Astrovirus

Epidemiology of Pediatric Stool Samples

Figure 1: Epidemiology of viral infection of pediatric stool samples by RT-PCR

Viral shedding

EM vs. RT-PCR

Adult Stool Samples

Table 3: Comparison of sensitivitiy and specificity of electron microscopy vs. RT-PCR for detection of viruses in stool.

Figure 2: Norovirus GII detected in stool samples from adult patients sent to viral laboratory at CHCO for EM testing October 2006 – January 2007

Some inpatients and BMT/ONC patients had multiple samples collected over the course of their illness and treatment. 329 samples were collected from 112 patients, and of these, 18 patients had multiple samples positive for at least one virus.

1.  Noroviruses and adenoviruses are common causes of gastroenteritis in children.

2.  Our data support the use and superiority of RT-PCR compared to electron microscopy for the diagnosis of viral gastroenteritis.

3.  Samples from adults reflect a norovirus outbreak in the community in the winter of 2006-2007.

4.  Immunocompromised patients can be infected with multiple viruses and shed viruses in their stools for prolonged periods

5.  Continued targeted efforts at novel prevention and therapeutic interventions for noroviruses are warranted.

6.  Burden of illness of viral gastroenteritis remains high, and this warrants development of rapid diagnostic assays and evaluation of severity of disease by virus.

Christina M Osborne, BA- M.D. Candidate, 2014 Children’s Hospital Colorado Department of Pediatrics, Section of Infectious Diseases 13123 E. 16th Ave Aurora, CO 80045 christina.osborne@ucdenver.edu I have no relevant conflicts of interest to disclose. Funding: NIH 1K08-AI073525-04A1; University of Colorado School of Medicine- Research Track

Table 4: Duration of virus shedding in patients on bone marrow transplant or oncology services as determined by consecutive positive samples.

Conclusions Table 1: Overall results by multiplex RT-PCR for all adult and pediatric stool samples submitted to study