Israel Medical Association Journal

Background: In trials comparing different formulations of measles vaccine, excess non-specific mortality occurred in female children who received high titer vaccine. These findings suggest a gender-specific effect of measles vaccine.

Objectives: To determine whether gender differences exist in the rates of adverse reactions and morbidity in the month following immunization with measles-containing vaccine, and to evaluate whether there is a gender-specific association between the humoral immune response to measles vaccination and post-vaccination morbidity.

Methods: Parents completed questionnaires on the health status of 755 infants aged 15-20 months, during the month preceding and the month following the measles-mumps-rubella vaccination. Blood samples were tested for measles antibody titers in a subsample of 237 infants.

Results: After controlling background morbidity in the infants, the relative risk of fever and rash following vaccination was 2.35 in females and 1.36 in males. The geometric mean antibody titers against measles were similar in both sexes and there was no significant association between antibody titer and post-vaccination morbidity in either sex.

Conclusions: Our findings demonstrate higher rates of adverse effects in females following vaccination with MMR vaccine, irrespective of the humoral response. This study emphasizes the need to consider possible gender differences when evaluating new vaccines.

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MMR= measles-mumps-rubella

Background: Chickenpox is a highly contagious childhood infection caused by varicella zoster virus, a virus of the herpes family. Although a mild and self-limiting disease in otherwise healthy children, chickenpox can be a complicated and even life-threatening disease in adults, pregnant women and immunosuppressed individuals. Among infants whose mothers had varicella during the first trimester of pregnancy, 2-3% will develop a congenital VZV syndrome that includes a combination of scarring, limb deformation, central nervous system impairment and ocular injury. In 1974, a live attenuated virus vaccine against VZV was developed in Japan and has been thoroughly tested for safety, efficacy and long-term effects. In March 1995 the vaccine was licensed in the U.S. for use in healthy children only.

Objectives: To determine the rate of immunity to VZV in young Israeli adults.

Methods: On the assumption that a randomly picked sample of 18-year-old army recruits in Israel is representative of the general Jewish population, 900 sera samples were taken for 3 years (1985,1988,1992). The sera were analyzed for IgG to VZV with a commercial ELISA kit using microwells coated with VZV antigens.

Results: A total of 98% of the samples tested positive for VZV antibodies. The difference in serologic values between the recruitment years was not statistically significant.

Conclusion: The majority of the Israeli population reaches adulthood already immunized against VZV, with immigrants having slightly lower immunity rates. Nonetheless, a few dozen cases of chickenpox are diagnosed in the IDF annually. These data should be taken into account when a vaccination program is devised. Should such a program be implemented, it would be interesting to repeat the serosurvey for comparison. A shift in the peak occurrence age might necessitate the administration of a booster vaccine at an older age.

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VZV= varicella zoster virus

IDF= Israel Defense Forces

Background: Despite current treatment protocols, the long-term complications of insulin-dependent diabetes mellitus have prompted the investigation of strategies for the prevention of IDDM.

Objectives: To investigate the effect of oral vanadate in reducing diabetes type I in non-obese diabetic mice.

Methods: Sodium metavanadate, 3.92 mmol/L, was added to the drinking water of 8-week-old female NOD mice. Blood glucose levels, water consumption and body weight were measured, and the end point of the study was judged by the appearance of hyperglycemia in the mice.

Results: Treatment with vanadate did not significantly reduce the incidence of type I diabetes as compared to the control group. However, oral vanadate therapy significantly reduced the blood glucose levels after the fourth week of treatment compared to the control group (3.83±10.67 vs. 4.44±10.83 mmol/L, P<0.03). There was a consistent and significant increase in body weight of the vanadate-treated pre-diabetic NOD mice compared to the controls. Diabetic mice treated with vanadate had significantly lower levels of serum insulin as compared to control diabetic mice (104±27 vs. 151±36 mol/L, P<0.03). Histologically, no significant differences were found in inflammatory response of the islets of Langerhans between the control and treated groups.

Conclusions: This study suggests that the post-receptor insulin-like effect induced by vanadate is not sufficient to prevent the development of diabetes and insulitis in pre-diabetic NOD mice.

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IDDM= insulin-dependent diabetes mellitus

NOD= non-obese diabetic