Moyes Cd

VERY-LOW-DOSE HEPATITIS B VACCINE IN NEWBORN INFANTS: AN ECONOMIC OPTION FOR CONTROL IN ENDEMIC AREAS

Three 1 microgram or 2 micrograms doses of Merck, Sharp and Dohme plasma vaccine were given to 119 infants of mothers negative for antibody to hepatitis B surface antigen (anti-HBs). Anti-HBs antibodies developed in 25/29 (86%) infants given 1 microgram and in 86/90 (96%) given 2 micrograms doses. Levels of anti-HBs achieved by three 2 micrograms doses were similar to those that have been reported for conventional 10 micrograms doses. Similar levels were recorded from infants of anti-HBs-positive mothers, which suggests that maternal antibody does not interfere with the infants immune response to low doses of vaccine. Three 2 micrograms doses of vaccine in infancy produce satisfactory immunogenicity and make possible economic control of hepatitis B in endemic areas.

Liver function of hepatitis B carriers in childhood

This study followed 314 children who were carriers of hepatitis B virus for 2 to 4 years and compared them with noncarriers, matched for age and sex, from the same community. No confirmed carrier lost hepatitis B surface antigen. Hepatitis B e antigen (HBeAg) was lost at a rate of 10.6% per year; the rate of decay was not affected by age or gender. Liver enzymes were higher in HBeAg-positive than in HBeAg-negative carriers and loss of HBeAg was usually followed by return to values in the normal range. There was evidence, however, of persistent mild liver dysfunction in carriers even after development of antibody to HBeAg. Serum alanine aminotransferase concentrations above twice the upper limit of normal were observed in 7% of carriers on at least one occasion but persisted for more than 1 year in less than 1% and clinical manifestations were rare. The hepatitis B carrier state was uncomplicated during the course of this study. However, risks of subsequent serious disease in adult life may be significant and continued surveillance of carriers is important for individual protection and to determine adverse prognostic features.

Cross-sectional survey of risk factors for asthma in 6–7-year-old children in New Zealand: International Study of Asthma and Allergy in Childhood Phase Three

Aim:  To identify risk factors for asthma in primary school‐aged children in New Zealand.

Time trends and risk factors for rhinoconjunctivitis in New Zealand children: an International Study of Asthma and Allergies in Childhood (ISAAC) survey.

Aim:  To investigate prevalence, time trends and factors associated with rhinitis and rhinoconjunctivitis not related to acute infections in New Zealand.

Time trends, ethnicity and risk factors for eczema in New Zealand children: ISAAC Phase Three.

Background Eczema is a common chronic disease which has significant morbidity and costs for children and their families. Phase One (1993) of the International Study of Asthma and Allergies in Childhood (ISAAC) found a high prevalence of symptoms of eczema in New Zealand. Objective In Phase Three (2001-3) we aimed to answer these three questions: Is the prevalence of eczema changing over time?; Are there ethnic differences in prevalence?; and What are the risk factors for eczema? Methods Five New Zealand centres participated in ISAAC Phases One and Three using the same methodology. Questionnaires about ethnicity, symptoms of eczema and environmental factors were completed by parents of 6-7 year olds (children) and self-completed by 13-14 year olds (adolescents). Prevalence and change per year were calculated by centre, ethnicity and gender. Prevalence differences between centres and associations with environmental factors were examined using logistic regression. Results There was little change in prevalence over time for the children, and a decrease in prevalence for the adolescents. Prevalence was higher among Māori and even higher among Pacific participants than among European children. Positive associations with current eczema symptoms were found for both age groups for truck traffic in the street of residence, and current paracetamol consumption, and for children only, antibiotics or paracetamol in the 1st year of life. Inverse associations were found with residence in New Zealand less than 5 years, consumption of milk, seafood, and eggs, and presence of a dog in the home. Conclusion Eczema remains a significant problem, particularly for young Māori and Pacific New Zealanders in whom less recognition of eczema and poorer access to effective, sustained eczema management may be contributing factors. Reverse causation may explain all the environmental findings apart from truck traffic which is increasing in New Zealand.