Pacyna J1, Terry S. J. 1, Siwek K. 1, Roberton E.S. 1, Johnson R.B. 1 and Davidson G.P.2
1NorthField Laboratories Pty Ltd., South Australia 5086 Australia. 2 Department of Gastroenterology, Women’s and Children Hospital, North Adelaide, South Australia, Australia.
4th Annual Conference on Vaccine Research 23-25 April, 2001, Virginia, USA

ABSTRACT:

In view of recently describe complication associated with oral vaccine to rotavirus we conducted several studies' to investigate alternative ways of protection by using antirotavirus antibody derived from hyperimmune bovine colostrum. The main interest of the study was to define the protective as well as survived property of antibody delivered orally to children in Childcare Centres. The study was conducted in two parts. First trial focus on efficacy of antirotavirus hyperimmune bovine colostrum (HBC-R) in the prevention of rotavirus diarrhoea. Children from 22 centres (n=742) in Adelaide participated in the study for over 20 weeks during the rotavirus season. Participants were divided into three groups and received product 3 times per day. Active group (n=245) received HBC-R, Control group (n=238) received placebo product and 259 were monitored but did not receive either product. The statistical analysis showed a significant reduction in the incidence rate of rotavirus diarrhoea (p=0.018). Children received milk supplemented with rotavirus antibody shown 84% protection compare to the other. Second trial concentrate on survival of orally administered antibody. Therefore small group for children (n=105) participated in the study. All participants were divided into 5 study groups. Three groups received different level of antirotavirus antibody in liquid form of HBC-R, one group revived reconstituted powder form of HBC-R mix in whole milk and control group received whole milk only. Approximately 1,500 faecal samples were collected during the study and tested for presence of rotavirus antigen or antibody. The antibody activity was detected in 86% of samples from subjects using product supplemented with HBC-R. A strong relation (r=0.81) was define between the level of antibody ingested and level of antibody detected in the faeces. Antibody activity was detected as early as 8 hours after first ingestion of HBC-R and up to 72 hours after last consumption of HBC-R. Our studies provide sufficient data to support hypothesis that antirotavirus antibody administered orally can protect the children from the rotavirus infection presumably due to they successful survival passage through the gastrointestinal tract. However passive immunity is only the temporally protection, but that can be used to effectively prevent from rotavirus as an alternative to direct oral vaccination.