Jh. Bruning et al., EFFECTS OF IODIZED OIL ON TRIVALENT ORAL POLIO VACCINE IN-VITRO, International journal for vitamin and nutrition research, 64(2), 1994, pp. 125-129
Iodine deficiency can be effectively reversed by administration of iod
ized oil (IO). Since 1989, the WHO Expanded Programme on Immunization
recommended delivery of oral IO along with vaccines, in appropriate si
tuations. However, administration of IO at the same time as trivalent
oral polio vaccine (TOPV) has not been recommended because of absence
of studies addressing potential harmful effects of iodized oil on immu
no-responses to TOPV. In this study an in-vitro cell culture system wa
s used to measure possible adverse effects of IO on TOPV. The system i
tself was shown not to be influenced by either IO or a standard non-io
dized oil (NIO). However, marked effects of IO on virus infectivity wa
s measured when a 50% mixture of IO and TOPV was incubated for 48 h at
37-degrees-C, as compared to incubation without IO. Clear differences
were found in effects of IO on vaccines of different sources, suggest
ing differences in composition of these vaccines, e.g. in stabilisers.
Principally Sabin 3 appeared susceptible to IO under the given extrem
e conditions. Pre-dilution of the IO-TOPV mixture prior to incubation
clearly reduced the effects of IO on virus infectivity Inoculation of
the IO/TOPV-mixture directly onto susceptible cells, a model approachi
ng the in vivo situation, resulted in no detrimental effects on virus
infectivity. Further studies are planned looking at interactions of io
dized oil and TOPV in children at immunization contacts.