A descriptive hospital based study of rotavirus diarrhoea in children aged 6 months to 3 years

Objective: To study the prevalence, demographic characteristics, clinical characteristics, laboratory parameters and therapy of rotavirus diarrhoea in children aged 6 months to 3 years in a hospital setting Method: A prospective hospital based crosssectional study was carried out in Sri Guru Ramdas Institute of Medical Sciences and Research on 50 consecutive children aged 6 month to 3 years with diarrhoea from December 2011 to June 2013. Stool samples were collected and rotavirus antigen detection was done by the Enzyme Immunoassay method. Stool microscopy and culture were done to find out bacterial and other causes for diarrhoea. Data so obtained was statistically analysed. Results: Out of 50 patients 22 tested positive for rotavirus by FAR diagnostic rotavirus card ELISA test. Prevalence of rotavirus diarrhoea in our study was 44%. Rotavirus diarrhoea was found most commonly in 6-12 months age group and in the months of October to December. Most of the patients presented with some dehydration. Conclusions: Prevalence of rotavirus diarrhoea in our hospital based study was 44%. The consistency of stools was watery in a significant number of rotavirus diarrhoea patients compared to nonrotavirus patients (p<0.05). A significant number of cases with rotavirus diarrhoea had some dehydration compared to non-rotavirus patients (p<0.05). (


Introduction
There is a lack of nationally representative data on the incidence of severe rotavirus disease in India 1 . Previous studies in the Indian Rotavirus Strain Surveillance Network have confirmed that _________________________________________ 1 Professor, 2 Junior Resident, 3 Associate Professor Department of Paediatrics, 4  rotavirus accounts for 39% of acute diarrhoeal hospitalizations 2 . We aimed to study the prevalence, demographic characteristics, clinical characteristics, laboratory parameters and therapy of rotavirus diarrhoea in children between 6 months to 3 years.

Method
This is a hospital based prospective, cross sectional descriptive study done in Sri Guru Ramdas Institute of Medical Sciences and Research from December 2011 to June 2013. All children aged 6 months to 3 years with chief complaints of loose stools and/or vomiting, after receiving informed consent from parent/guardian, were included in the study. Children over 3 years of age were excluded from the study.
A case of diarrhoea was defined as increased stool frequency compared with the usual pattern for which parents sought care for treatment of diarrhoea. The indications for hospitalization were (i) severe dehydration requiring intravenous hydration (ii) malnourished children with dehydration (iii) toxic appearance, changing mental status (iv) high output diarrhoea (>10 large volume stool/day) (vi) persistent vomiting or diminished or no oral intake (vii) suboptimal or no response to oral rehydration therapy (ORT) or further deterioration (viii) inability of the caregiver to administer oral rehydration salts (ORS) 3 .
History of fever, loose stools, vomiting and the duration of presenting complaints was obtained from the parent/guardian according to proforma. Data about exclusive breast feeding and about current feeding pattern was also assessed. Anthropometry was done to find out grade of malnutrition. Temperature, pulse and blood pressure was checked. Children were assessed for signs of dehydration and classified as per WHO Integrated Management of Childhood Illness Model Handbook guidelines and was categorized into severe, some or no dehydration 3 .
Stool samples of all the children presenting with diarrhoea were collected in sterile containers and tested in side laboratory in ward for presence or absence of rotavirus antigen. Other stool samples were sent to microbiology department of SGRDIMSR hospital for routine examination and stool culture and sensitivity. ELISA testing (Rotavirus card, FAR diagnostics) was used to test for Rotaviral antigens in stool. The enzyme-linked immune-sorbent assay is highly sensitive (100%) and specific (97%) for rotavirus antigen 4. Venous blood samples, collected under aseptic precautions, were sent for haemoglobin estimation, total and differential blood counts and serum electrolytes. A clean catch midstream urine sample was collected and subjected to routine examination and culture sensitivity.
Data was collected and entered in Microsoft Excel 2010. For inferential analysis, Chi-square and independent t-test were calculated at the level of significance p=0.05 (Confidence interval=95%). Analysis was done using SPSS software, Version 11.5.

Results
Stools samples of 50 patients presenting with acute diarrhoea were subjected to rotavirus card test and prevalence of rotavirus diarrhoea was found to be 44% (n=22) (Figure 1).

Figure 1: Prevalence of rotavirus diarrhoea in study group
The demographic characteristics and feeding pattern of the 50 patients are shown in Table 1. The clinical characteristics of the 50 patients are shown in Table 2.

ROTAVIRUS CARD TEST
Negative Positive  Table 2).
The laboratory parameters of the 50 patients are shown in Table 3. Treatment of the patients in study group was done as per WHO guidelines according to degree of dehydration (Table 4).  Oral rehydration solution (ORS) was given to all 50 patients. Oral zinc was given for 14 days in all patients.

Discussion
In our hospital-based study we found a prevalence of rotavirus diarrhoea of 44%. Mathew et al in Ernakulam district, Kerala also detected rotavirus in 36% of diarrhoea-related hospital admissions among children less than 5 years of age 5 . In our study 36% of rotavirus positive cases were in the 6-12 month age group and 27% cases in the 19-24 month age group. Similar results were reported in a study by Mathew et al who reported high prevalence in children aged 6 -11 months and 12-23 months (32% and 42%, respectively) 5 . A study by Grimwood et al in New Zealand also showed rotavirus detection rate to be 27% in infants aged 0-5 months, 43% in infants aged 6-11 months, and 52% in the 12-35 month age group ( p < 0.001) 6 .
Of the 22 patients with rotavirus diarrhoea in our study 40% were male. Proportion of male and female patients were 53% and 47% respectively in a study done by Azemi M et al in Kosovo 7 . In our study we found that 40% of cases with rotavirus diarrhoea were seen from October-December and 31% from July-September. Most studies have observed an increase in rotavirus-associated diarrhoea during the winter months, October to February, throughout the country ranging from 59% to 72%, with a median of 64%. The northern, more temperate regions may exhibit stronger seasonality 8  In our study ORS and oral zinc were given to all 50 patients. Intravenous fluids were needed in 81% patients with rotavirus diarrhoea and 64% patients with non-rotaviral diarrhoea. Nalin DR et al observed that oral therapy is safe and effective for rehydration in most infants with 5-10% dehydration due to viral or bacterial diarrhoea 14 . In our study we found that the mean hospital stay in rotavirus diarrhoea was 3±2 days as compared to 4±1 days in non rotaviral group. Kurugol Z et al on the other hand observed that the mean hospital stay for rotavirus gastroenteritis was significantly longer 5.5±5.1 days compared to 3±3.1 days for nonrotavirus gastroenteritis 15 .

Conclusions
• In the 6 month-3 year age group the prevalence of rotavirus diarrhoea was 44% in our hospitalbased study. • The consistency of stools was watery in a significant number of rotavirus diarrhoea patients compared to non-rotavirus patients (p<0.05). • A significant number of cases with rotavirus diarrhoea had some dehydration compared to non-rotavirus patients (p<0.05).