Report No FR0002

July 1989

I OBJECTIVES

1. To compare the adsorption of human rotavirus to 3 categories of marine sediment, fine, medium and coarse, whose particle size and composition have been determined.
   
2. To assess the efficiency of trickling filtration for the removal of rotavirus during the early spring, when rotaviral gastroenteritis is most prevalent and when rotavirus numbers in sewage are highest.

II REASON

Rotavirus is recognised as a major cause of severe infantile diarrhoea and can also cause gastroenteritis in adults. Sea outfalls are currently designed to meet bacterial, rather than viral, standards. In order to improve the effectiveness of sewage treatment and disposal, more information is needed on the fate and inactivation of viruses in the sea, and the effectiveness of different means of sewage treatment in removing viruses.

III CONCLUSIONS

1. Rotavirus has a high affinity for adsorption to sediments, but it was not possible to differentiate between efficiency of adsorption to different sediment types.
   
2. Viruses persist in sewage even after secondary treatment.

IV RECOMMENDATIONS

The sediment adsorption experiments need to be repeated using wet sediment or dried sediment which has been rinsed with distilled water to remove concentrated salts. These experiments should be carried out using larger quantities of rotavirus on smaller volumes of sediment.

To improve the detection of rotavirus in sewage, that element of sewage which is toxic to the cell monolayer on which viruses are cultured, needs to be removed. Further work is required to improve the methodology currently available.

V RESUME OF CONTENTS

This report reviews the literature and describes the progress of studies to examine the adsorption of rotavirus onto coarse, medium and fine sediments, and to assess the efficiency of different stages in sewage treatment in removing rotavirus.

Copies of the report are available from FWR, price £25.00, less 20% to FWR Members.