Enteric viruses have been shown to be responsible for diarrhea among children during their early childhood. This study was carried out to determine the prevalence of rotavirus, adenovirus, and norovirus infection in young children with diarrhea in two primary health centers in Edo State, Nigeria. A total of 223 stool specimens were collected from children aged 0–36 months with clinical signs of diarrhea and 59 apparently healthy age-matched children as control. These specimens were investigated for three viral agents using immunochromatographic technique (ICT). The overall results showed that at least one viral agent was detected in 95/223 (42.6%) of the children with diarrhea while the control had none. The prevalence of rotavirus was 28.3%, adenovirus 19.3%, and norovirus 3.6%. There was a significant association between age group and infection (
Enteric viruses are major etiologic agents of acute gastroenteritis among infants and young children worldwide. Rotavirus, norovirus, adenovirus, and astrovirus are the recognized viral causes of pediatric gastroenteritis [
There is paucity of information as regards viral enteropathogens of diarrhea in many developing countries including Nigeria. Many hospitals in Nigeria do not carry out routine diagnostic tests for viral diarrhea. Investigations on diarrheal infections are usually based on bacterial and parasitic agents. The reason(s) attributed to this may be as a result of the poor health care system in the country where important health issues are taken for granted such as the aforementioned case. Thus, as a result of the nonperformance of viral tests for diarrheal patients, information on viral enteropathogens is lost and thus measures to implement control strategies become difficult. Against this background, this study was carried out to ascertain the prevalence of rotavirus, adenovirus, and norovirus infection in young children with diarrhea in two primary health centers in Edo State, Nigeria. It also aimed at assessing the coinfection rates of the viral agents, age, seasonal distribution of infection, and the association between clinical symptoms and viral diarrhea.
This study was carried out in two primary health centers located in Ikpoba-Okha Local Government Area of Edo State, Nigeria. The health centers attend to the primary health needs of the people within and around the locality. Cases attended to include malaria, diarrhea, immunization of infants and children, antenatal and postnatal cases, and other minor health issues within the scope of the health personnel. The two primary health centers are Aduwawa and Evbomodu primary health centers and they are neighboring communities with a fast growing population made up of indigenes with new residents from the main city alongside other inhabitants from other parts of the country.
A total of two hundred and eighty-two (282) stool specimens comprising 223 diarrhea and 59 nondiarrhea stool specimens were collected from children aged between 0 and 36 months attending two primary health centers. As regards children with diarrhea, males were 121 while females were 102. Similarly, for the control, males were 33 while females were 26. Verbal informed consent was obtained from patients or guardian of the children prior to sample collection. Demographic and clinical information were obtained by means of structured questionnaire. The study was carried out from January 2011 to June 2012. Ethical approval was obtained from the local government health ethics committee.
The samples were collected from patients at the time of clinic visit as well as other times when the child defecates. Sterile wide mouth specimen containers were used for specimen collection and they were processed within 6 hours of collection. Rotavirus, adenovirus, and norovirus were detected by the immunochromatographic technique (ICT). Rotavirus and adenovirus were detected using VIKIA Rota-Adeno rapid test device manufactured by BioMerieux, France. Briefly, 2 drops of liquid stool specimen was added to the specimen dilution buffer and shaken vigorously to homogenize. Two drops of the diluted sample was transferred to the sample well of the test device (cassette) and was timed for 10 minutes. Results were interpreted according to the manufacturer’s instructions. Similarly, norovirus was detected using RIDA Quick norovirus (NI403) test device manufactured by R-Biopharm AG, Germany. Briefly, 1 mL of sample dilution buffer (diluent) was placed in a separate labeled test tube and 100 mL of liquid stool was added to it and shaken vigorously to homogenize. This was allowed to settle for 2 minutes and 250
Statistical analysis was carried out using odd ratio and chi-square (
A total of 223 children with diarrhea were tested for three viral agents (rotavirus, adenovirus, and norovirus). A total of 95 (42.6%) were positive for at least one viral agent while none of the 59 children without diarrhea was positive for any viral agent. The overall result showed that rotavirus had a prevalence of 63 (28.3%) (Table
Prevalence of three enteric viruses among children with diarrhea.
Enteropathogens |
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Percentage |
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Number of children with at least one virus | 95 | 42.6 |
Rotavirus | 63 | 28.3 |
Adenovirus | 43 | 19.3 |
Norovirus | 8 | 3.6 |
Sex and age distribution of viral enteropathogens.
Characteristics | Number tested | Number positive (%) | Rotavirus positive (%) | Adenovirus positive (%) | Norovirus positive (%) |
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Sex | |||||
Male | 121 | 54 (44.6) | 36 (29.8) | 19 (15.7) | 5 (4.1) |
Female | 102 | 41 (40.2) | 27 (26.5) | 24 (23.5) | 3 (2.9) |
Total |
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Age group (months) | |||||
0–6 | 63 | 32 (50.8) | 20 (31.7) | 14 (22.2) | 2 (3.2) |
7–12 | 82 | 48 (58.5) | 31 (37.8) | 23 (28.0) | 3 (3.7) |
13–18 | 35 | 8 (22.9) | 7 (20.0) | 3 (8.6) | 2 (5.7) |
19–24 | 26 | 5 (19.2) | 4 (15.4) | 2 (7.7) | 1 (3.8) |
25–30 | 11 | 2 (18.2) | 1 (9.1) | 1 (9.1) | 0 |
31–36 | 6 | 0 | 0 | 0 | 0 |
Total |
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Monoinfection, coinfection, and pattern of coinfection of enteric viruses.
Characteristics | Number positive (%) | Rotavirus positive (%) | Adenovirus positive (%) | Norovirus positive (%) |
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Monoinfection | 78 (35.0) | 47 | 28 | 3 |
Coinfection | 17 (7.6) | 16 | 15 | 5 |
Total |
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Coinfection pattern | Number of patients | Percentage |
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Rotavirus + adenovirus | 12 | 5.4 |
Rotavirus + norovirus | 2 | 0.9 |
Adenovirus + norovirus | 1 | 0.4 |
Rotavirus + adenovirus + norovirus | 2 | 0.9 |
Total |
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Seasonal pattern of enteric viruses and distribution according to health centers.
Characteristics | Number tested | Number positive (%) | Rotavirus positive (%) | Adenovirus positive (%) | Norovirus positive (%) |
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Season | |||||
Dry | 95 | 35 (36.8) | 24 (25.3) | 15 (15.8) | 2 (2.1) |
Rainy | 128 | 60 (46.9) | 39 (30.5) | 28 (21.9) | 6 (4.7) |
Total |
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Health centers | |||||
Evbomodu | 128 | 55 (43.0) | 36 (28.1) | 23 (18.0) | 5 (3.9) |
Aduwawa | 95 | 40 (42.1) | 27 (28.4) | 20 (21.1) | 3 (3.2) |
Total |
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Distribution of rotavirus, adenovirus, and norovirus positive patients by some variables.
Variables | Rotavirus positive |
Adenovirus positive |
Norovirus positive |
Total |
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Fever | ||||
Yes | 21 (33.3) | 13 (30.2) | 1 (12.5) | 35 (30.7) |
No | 42 (66.7) | 30 (69.8) | 7 (87.5) | 79 (69.3) |
Total |
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Vomiting | ||||
Yes | 35 (55.6) | 24 (55.8) | 6 (75.0) | 65 (57.0) |
No | 28 (44.4) | 19 (44.2) | 2 (25.0) | 49 (43.0) |
Total |
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Dehydration | ||||
Yes | 21 (33.3) | 14 (32.6) | 2 (25.0) | 37 (32.5) |
No | 42 (66.7) | 29 (67.4) | 6 (75.0) | 77 (67.5) |
Total |
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Abdominal pain | ||||
Yes | 11 (17.5) | 6 (14.0) | 1 (12.5) | 18 (15.8) |
No | 52 (82.5) | 37 (86.0) | 7 (87.5) | 96 (84.2) |
Total |
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The prevalence of rotavirus, adenovirus, and norovirus infections was investigated among children with diarrhea. The age range of the children was 0 to 36 months. The overall prevalence of viral agents was 42.6%. The results of this study when compared to other studies carried out in Nigeria and other parts of the world showed that the incidence of viral agents varied from one locality to another. The 28.3% of rotavirus in this study is lower than 55.9% in Ilorin, Nigeria [
There was a statistical significance between infection and age group (
In this study, coinfection rate was 7.6%, and rotavirus-adenovirus coinfection was the highest with 12 (5.4%). This is consistent with studies in Nigeria and Spain [
The seasonal pattern of viral infection was not statistically significant (
The most commonly associated clinical symptom observed in this study with rotavirus, adenovirus, and norovirus positive cases was “vomiting” with 55.6%, 55.8%, and 75.0%, respectively. This finding is similar to other studies [
In this study, viral agents associated with diarrhea were found to be 42.6%. Coinfection of viral agents was found to be 7.6% and the most common clinical symptom was vomiting. This is worrisome considering the burden of these viruses on the young children in this locality. The fact that viral diagnostic tests are not routinely done or rarely done in any of the hospitals in this locality means that such vital information on viral diarrhea is missed out due to the poor attention given to health care in the country. Thus, there is need to test stool specimens of clinically confirmed diarrheal patients for enteric viruses as this will go a long way in reducing the wasteful use of antibiotics which are used as blind treatment for persistent diarrhea that may be of viral origin. Finally, the primary health care centers should be provided with all the necessary diagnostic test materials to address cases of viral diarrhea.
The authors declare that they have no conflict of interests regarding the publication of this paper.
The authors acknowledge with thanks the staff of Evbomodu and Aduwawa primary health centers for their assistance.