Abstract Title
High Levels of Co-detection of Norovirus and Other Enteric Co-Pathogens in Hospitalized Patients With and Without Acute Gastroenteritis in Bangladesh
Presenter
Farzana Fariha, International Center for Diarrheal Disease Research, Bangladesh
Co-Author(s)
Farzana Fariha, International Centre for Diarrhoeal Disease Research, Bangladesh ,
Sharmeen Akter Urmi, International Centre for Diarrhoeal Disease Research, Bangladesh,
Mohammad Enayet Hossain, International Centre for Diarrhoeal Disease Research, Bangladesh, Probir Kumar Ghosh, International Centre for Diarrhoeal Disease Research, Bangladesh ,
Md. Mahfuzur Rahman, International Centre for Diarrhoeal Disease Research, Bangladesh ,
Faruq Abdullah, International Centre for Diarrhoeal Disease Research, Bangladesh ,
Mustafizur Rahman, International Centre for Diarrhoeal Disease Research, Bangladesh ,
Adiba Hassan, Center for Disease Control and Prevention, Atlanta, Georgia, USA,
Rashi Gautam, Center for Disease Control and Prevention, Atlanta, Georgia, USA,
Jan Vinjé, Center for Disease Control and Prevention, Atlanta, Georgia, USA,
Sara Mirza Center for Disease Control and Prevention, Atlanta, Georgia, USA,
Paul A. Gastañaduy, Center for Disease Control and Prevention, Atlanta, Georgia, USA,
Syed M Satter, International Centre for Diarrhoeal Disease Research, Bangladesh
and Umesh D Parashar, Center for Disease Control and Prevention, Atlanta, Georgia, USA.
Abstract Category
Structure & Pathogenesis
Abstract
Introduction: Few studies concominantly assess the causative role of multiple enteropathogens in acute gastroenteritis (AGE). We summarize the frequency of norovirus detections and co-detections in Bangladesh and assess how co-detections influenced prior findings of higher norovirus prevalence in controls compared to cases, as well as overlapping viral loads among these groups.
Methods: From March 2018–October 2021, 1,250 AGE cases and 1,250 non-AGE controls (age, sex, season, and site matched) were enrolled at 10 hospitals in Bangladesh. All norovirus-positive AGE cases (n=111) and non-AGE controls (n=182), and a randomly selected subset of 126 norovirus-negative cases, were tested for other enteric viral, bacterial, and parasitic co-pathogens with quantitative real-time PCR assays. We compared single norovirus and co-detection proportions and genogroup II norovirus cycle threshold (ct)-values among norovirus-positive AGE cases and non-AGE controls.
Results: Overall, 92% (218/237) of AGE cases had ≥1 enteropathogen detected. Among AGE cases and non-AGE controls, norovirus was detected as a single pathogen in 2% (29/1,250) and 5% (59/1,250) respectively, and as a co-detection in 7% (82/1,250) and 10% (123/1,250), respectively. Among 240 norovirus-positive patients, 38 were positive for genogroup I and 202 were positive for genogroup II. The median (interquartile range) ct-values among norovirus-only AGE cases, norovirus co-detection AGE cases, and norovirus-positive non-AGE controls were 26 (21–31), 25 (20–29), and 25 (18–29), respectively.
Conclusions: High levels of mixed detections of norovirus and other enteric pathogens, and similar norovirus ct-values in patients with and without diarrhea, makes attribution of norovirus to diarrhea very challenging in Bangladesh.
Methods: From March 2018–October 2021, 1,250 AGE cases and 1,250 non-AGE controls (age, sex, season, and site matched) were enrolled at 10 hospitals in Bangladesh. All norovirus-positive AGE cases (n=111) and non-AGE controls (n=182), and a randomly selected subset of 126 norovirus-negative cases, were tested for other enteric viral, bacterial, and parasitic co-pathogens with quantitative real-time PCR assays. We compared single norovirus and co-detection proportions and genogroup II norovirus cycle threshold (ct)-values among norovirus-positive AGE cases and non-AGE controls.
Results: Overall, 92% (218/237) of AGE cases had ≥1 enteropathogen detected. Among AGE cases and non-AGE controls, norovirus was detected as a single pathogen in 2% (29/1,250) and 5% (59/1,250) respectively, and as a co-detection in 7% (82/1,250) and 10% (123/1,250), respectively. Among 240 norovirus-positive patients, 38 were positive for genogroup I and 202 were positive for genogroup II. The median (interquartile range) ct-values among norovirus-only AGE cases, norovirus co-detection AGE cases, and norovirus-positive non-AGE controls were 26 (21–31), 25 (20–29), and 25 (18–29), respectively.
Conclusions: High levels of mixed detections of norovirus and other enteric pathogens, and similar norovirus ct-values in patients with and without diarrhea, makes attribution of norovirus to diarrhea very challenging in Bangladesh.