Laboratory diagnosis of rotavirus infection in infantile gastroenteritis using the Elisa technique

ABSTRACT

The magnitude of gastroenteritis and its co-partner malnutrition has been amply identified in Jamaican children under five years but especially in the 6-24 month age group which are the most vulnerable. At present steps are being taken to significantly improve the existing conditions and the results have been very rewarding. Although the nutritional aspect was not emphasised in the analysis of this study it is a fact that malnutrition co-exists with gastroenteritis and the malnourished child is more prone to infection from the causative agents of gastroenteritis. Results of this show that rotaviruses are important aetiological agents of gastroenteritis in Jamaica especially in the "cooler" months of the year. The higher prevalence of rotavirus infection in Jamaican children (5 years and under) in December to March, the cooler months of the year is significant. This could suggest that temperature might play a role in the occurrence of the virus, in addition, there was a definite drop in temperature during those months. This pattern of higher prevalence in winter or cooler months is in accord with findings of other investigators worldwide (King et al, personal communication; Davidson et al; Bryden et a;; Kapikian et al; Middleton et al). From the findings in this study we can conclude that rotavirus appears to be significantly associated with Infantile Diarrhoea in Jamaican children, that there is a higher incidence in the cooler months of the year, and that there is correlation with previous studies by other investigators in different parts of the world in different aspects like clinical factors, age and sex, socio-economic status of the patients also climatological variables. Sensitivity, low cost, reagent stability, ease of procedure are some of the virtues of the ELISA. These factors are in favour of using this technique as a routine laboratory method of rotavirus detection. However, it must be remembered that optimum reproducibility is important, therefore these tests should be rigidly controlled by the inclusion of reference negative and positive antisera at all times and the specificity is further ensured by performing the Blocking Test. Although there are so many advantages in using the ELISA test routinely in a laboratory, there are also disadvantages. Among these are dependence on a foreign source for reagents and the possibility of the occurrence of false positives which calls for a blocking procedure, therefore prolonging the test results. However, the use of the ELISA technique in rotavirus detection would be beneficial to developing countries like Jamaica, if conjugate and control serum could be made available to them routinely by W.H.O. or similar health organization, or these reagents could be obtained from a reliable commercial source at a low affordable cost (Summary)