Downloaded from http://journals.lww.com/pidj by BhDMf5ePHKbH4TTImqenVIiuKVF7qTxsQaiFjWWJFe9k5gE4Hx2jjyqt6gKmXBW5UJfPe1Ov9lU= on 06/22/2020 Copyright © 2020 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. 580 | www.pidj.com The Pediatric Infectious Disease Journal • Volume 39, Number 7, July 2020 Accepted for publication February 6, 2020. From the *Department of Microbiology, Jahangirnagar University, Savar, Dhaka, Bangladesh; †Department of Microbiology, Jashore University of Science and Technology, Jashore, Bangladesh; ‡Department of Zoology, Jahangir- nagar University, Savar, Dhaka, Bangladesh; and §Department of Physiol- ogy, Pabna Medical College, Pabna, Bangladesh. The authors have no funding or conflicts of interest to disclose. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (www.pidj.com). Address for Correspondence: Shuvra Kanti Dey, PhD, Department of Microbi- ology, Jahangirnagar, University, Savar, Dhaka-1342, Bangladesh. E-mail: shuvradey@yahoo.com. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved. ORIGINAL STUDIES Background: Diarrheal disease is one of the leading causes of childhood morbidity and mortality in the 21st century in developing countries. Mainly infants and young children develop diarrheal diseases. This study aims to determine the incidence of diarrheal pathogens in children in Bangladesh. Methods: During 2014 to 2019, 387 fecal specimens were collected from children with diarrhea in Bangladesh. Bacterial pathogens were detected by conventional bacteriologic, biochemical and molecular sequence analysis methods. DNA virus and RNA virus (diarrheal viruses) were detected using polymerase chain reaction and reverse transcriptase polymerase chain reac- tion, respectively and confirmed by molecular sequence analysis. Results: Bacterial infections were detected in 39.27% (152 of 387) of the stool samples. Escherichia coli was the most prevalent (17.3%) followed by Vibrio cholerae (13.5%), Salmonella spp. (4.9%) and Shigella spp. (3.6%). From 387 fecal specimens tested, 42.4% (164 of 387) were positive for viral infections. Rotavirus was the most prevalent (26.3%), followed by adenovi- rus (5.7%), norovirus (5.4%) and human bocavirus (4.9%). Dual infection between rotavirus and E. coli accounted for the largest portion of coinfec- tion (48%). Diarrhea (77%) and abdominal pain (65%) were most common followed by vomiting (63%), fever (43%) and dehydration (39%). E. coli and V. cholerae were most resistant against ciprofloxacin (62.7%) and tet- racycline (88.5%). qnrA and sul4 resistance genes were isolated from these pathogens. Conclusions: Data from this study underline the high incidence of diarrheal pathogens and presence of antibiotics resistance genes in a pediatric popula- tion in Bangladesh. Key Words: molecular epidemiology, diarrheal pathogens, antibiotic resist- ance, Bangladesh (Pediatr Infect Dis J 2020;39:580–585) A cute gastroenteritis is one of the major health problems in chil- dren worldwide. About 2.5 billion people are infected with diarrheal diseases and 1.5 million deaths occur due to diarrhea each year. 1,2 About 40% of this morbidity and 30% of the mortality are reported from children <5 years of age. 2–4 Most of the diarrheal diseases reported among children occur in the developing coun- tries. Most of the people in Bangladesh have poor socioeconomic and unhealthy living conditions so they are burdened with diarrheal diseases. 5 Though the morbidity of diarrheal diseases has been reduced by a large proportion in the last 2 decades worldwide, it is still among the top 5 causes of children mortality in developing countries. 5–7 Diarrhea can be caused by various types of bacteria, viruses, parasites or protozoa. 2,8 In Bangladesh, both the bacte- rial and viral pathogens are common among infants and young children with acute gastroenteritis. 9,10 Among bacterial pathogens, Escherichia coli, non typhoidal Salmonella spp. (NTS), Shigella spp. and Vibrio cholerae, are commonly reported. 3 E. coli is the member of human and other animals gut normal flora. But through adaptation and genetic changes some have acquired the ability to cause various human health problems. 11 About 200 sero- groups of E. coli are so far identified. Five or 6 types of E.coli are involved in human gastrointestinal disorders. 12 They are entero- toxigenic E. coli, enteropathogenic E. coli, enteroaggregative E. coli, Shiga-toxin-producing E. coli, enteroinvasive E. coli and diffuse-adherent E. coli or adherent-invasive E. coli. 13 Most of the E.coli infections are caused by enterotoxigenic E. coli and enteropathogenic E. coli in the developing countries of South- East Asia each year. 13,14 Salmonella spp. is another major enteropathogen causing children diarrheal diseases in developing countries. 15 About 2600 serotypes of Salmonella spp. have been so far isolated worldwide. They are classically divided into the human-restricted typhoidal Salmonella (Salmonella Typhi and Salmonella Paratyphi A and B) and NTS. 16 Salmonella enterica serovar Typhimurium and Salmo- nella Enteritidis are the most common human NTS serovars glob- ally. 14,17 Shigella spp. is also a common bacterial pathogen that causes diarrhea in children. 5 Four species of Shigella cause human disease: Shigella flexneri, Shigella sonnei, Shigella boydii and Shi- gella dysenteriae. S. flexneri is the most frequently isolated species worldwide and accounts for 60% of shigellosis in the developing countries. 18 V. cholerae has caused worldwide pandemics from prehistoric time. 19,20 Two hundred six serogroups of V. cholerae are present worldwide. Outbreaks of cholera have been caused by 2 serogroups—V. cholerae, O1 and O139. 21 About 5 million cases of morbidity and 0.1 million cases of mortality are reported to be associated with V. cholerae worldwide each year. 22 Viruses are the main pathogens in acute gastroenteritis worldwide in children. Rotavirus (RV) infects and kills more infants and children than any other diarrheal viruses. 3,5 After RV, norovirus (NoV) and adenovirus (AdV) are common diarrheal viruses associ- ated with infants and children with diarrhea. 23 Some other viruses such as astrovirus, sapovirus, Aichivirus, human bocavirus (HBoV) and hepatitis A virus are also reported to be associated with diar- rheal diseases in infants and children worldwide. 10,24 In the present study, incidence of bacterial infections among children in Bangladesh was determined along with the antibiotic ISSN: 0891-3668/20/3907-0580 DOI: 10.1097/INF.0000000000002637 Molecular and Epidemiologic Analysis of Diarrheal Pathogens in Children With Acute Gastroenteritis in Bangladesh During 2014–2019 Nadim Sharif, MS,* Nasir Uddin Nobel, MS,* Najmuj Sakib, MS,† Syeda Moriam Liza, MS,* Shafia Tasnim Khan, MS,* Baki Billah, PhD,‡ Anowar Khasru Parvez, PhD,* Aynul Haque, MD,§ Ali Azam Talukder, PhD,* and Shuvra Kanti Dey, PhD*