Oral polio vaccination in infants: beneficial effect of additional dose at birth.

This study was done to assess the response of newborns to trivalent oral polio vaccine and to study any efficacy of OPV if given to infants on third day of life. The study was conducted in two groups, A (87) and B (55) of infants in Delhi, India. In group A, the children received one birth dose or 'O' dose of TOPV, followed by 3 conventional doses started at 6 weeks, and in group B the children received only 3 doses of OPV. Pre and one month post immunization serum samples were tested for the presence of neutralising antibodies. In addition, in group A serum samples were collected at 6 weeks before the administration of 1st dose to see the sero response following 'O' dose of TOPV. It was found that administration of OPV on 3rd day of life leads to sero conversion in 15.3% of infants to all three polio virus types by the age of 6 weeks, and highest sero response was seen for polio virus type 1. Sero-conversion in group A was significantly more than sero-conversion in group B after the administration of last dose. Thus the study has established that immunization of newborns with TOPV is a safe and effective means for improving protection against the disease.

Increased production of IFN-gamma and cysteinyl leukotrienes in virus-induced wheezing.

BACKGROUND: An imbalance of production of T-helper lymphocyte cytokines, favoring overproduction of IL-4, is believed to be important in the pathogenesis of allergic asthma. However, less is known about the cytokine response in virus-induced wheezing, which is a major cause of morbidity in asthma. OBJECTIVE: We undertook this study to determine the magnitude of IFN-gamma, IL-4 and IL-10, and leukotriene (LT) responses in infants and children with virus-induced wheezing. METHODS: We measured the concentrations of IFN-gamma, IL-4 and IL-10, and cysteinyl LTs in respiratory secretions of 82 infants and young children during acute episodes of virus-induced wheezing. Control subjects were 47 infants and children with uncomplicated upper respiratory infections and 18 normal healthy infants. RESULTS: Ratios of IFN-gamma to IL-4 were higher (due to increased quantities of IFN-gamma) in subjects with wheezing than in those with upper respiratory infection alone (P =. 003). Quantities of LTs were also increased in wheezing subjects in comparison with those with upper respiratory infections (P =.009). There was a significant correlation between measured concentrations of IFN-gamma and LTs (correlation coefficient =.451, P =.007). Quantities of IL-4 were slightly suppressed in the wheezing groups. CONCLUSIONS: An imbalance favoring overproduction of IFN-gamma appears to be associated temporarily with virus-induced wheezing. A possible mechanism is the enhanced release of LTs from eosinophils or mast cells after sensitization by IFN-gamma.