Epidemiology and cost analysis of varicella in Italy: results of a sentinel study in the pediatric practice. Italian Sentinel Group on Pediatric Infectious Diseases.

BACKGROUND: Describing the epidemiology of varicella is relevant to the development of specific prevention strategies and to building up of economic models evaluating the cost:efficiency ratios of these strategies. AIM: Our study was designed to describe the epidemiology of chickenpox among Italian children and to assess the resulting economic and health burden on the country. METHODS: Thirty-nine Italian pediatricians participated in a sentinel network on pediatric infectious diseases representing a total pediatric population of 30 168 children. Each case of varicella observed from January through December, 1997, was recorded. Economic analysis was conducted from the societal point of view. All costs were broken down into two groups: direct and indirect costs. RESULTS: A total of 1599 cases of varicella were reported among children 0 to 14 years old. There were 1266 primary cases (mean age, 4.5 +/- 2 years) and 333 secondary cases (mean age, 3.6 +/- 3.2 years). The global incidence of chickenpox was 51.01/1000/year. Complications were seen in 56 cases (3.5%). Drugs were prescribed in 672 cases. A group of adults (364 susceptible and 193 with uncertain status) were exposed to primary cases. Seventy (12.5%) were eventually infected among whom there were 4 pregnant women. For pediatric patients an average cost of $146.90 (250 400 lire) was estimated; this is largely accounted for by indirect costs. CONCLUSIONS: The epidemiology of varicella in Italy is consistent with that found in previous studies in industrialized countries. Severe complications did not occur in our population. We believe that the health arguments in favor of universal vaccination of children > 18 months of age do not differ in our own country from those of other industrialized nations. Our data could now be incorporated into pharmacoeconomic models to establish cost-efficient strategies for Italy.

New seminal plasma removal method for freezing stallion semen.

Seminal plasma removal, an indispensable step in equine semen cryopreservation, is usually done by centrifugation, but this might cause mechanical damage to sperm. A new method for seminal plasma removal from stallion semen, namely a filter composed of a synthetic hydrophilic membrane (Sperm Filter, BotuPharma, Botucatu, Sao Paulo, Brazil), was recently proposed. The objective of this study was to test the use of the Sperm Filter in the removal of seminal plasma before freezing stallion semen. Ejaculates from 31 stallions were divided into two groups and cryopreserved. In group 1 (G1), seminal plasma was removed with the Sperm Filter, and in group 2 (G2), seminal plasma was removed by centrifugation (600×g for 10 minutes). There were no differences (P < 0.05) between G1 and G2 in sperm kinetic parameters or plasma membrane integrity before or after cryopreservation. However, sperm recovery rate was higher (P < 0.05) for G1 versus G2 (mean ± SD, 89.4 ± 7.4% vs. 80.9 ± 5.5%). Therefore, the Sperm Filter was as efficient as centrifugation in removing seminal plasma from the stallion ejaculate. However, filtering was more practical and had significantly fewer sperm lost than the centrifugation technique.

Immunity to diphtheria and tetanus in a young population on a dialysis regimen or with a renal transplant.

In 54 transplant recipients diphtheria and tetanus immunity after primary vaccination was significantly lower than in 57 control subject and 35 patients on a dialysis regimen. After a booster, tetanus antibodies developed in the transplant recipients and dialysis patients but no diphtheria antibodies developed in two transplant recipients. No adverse reactions, including acute graft rejection episodes, occurred.

Duration of immunity to diphtheria and tetanus in young kidney transplant patients.

A considerable proportion of patients with renal transplant, evaluated many years after transplant, lack protective diphtheria antibody levels, despite primary immunization, but maintain immunity to tetanus. These patients respond to a diphtheria and tetanus booster but the duration of the response is uncertain. This study was undertaken to assess if protective antibodies evoked by primary immunization are lost quickly after transplantation, and whether the extent of the immune response to a booster influences the persistence of protective antibodies. We studied 15 patients (group 1) immediately after renal transplant and 35 patients with renal transplant for 6 +/- 4 yr who received a diphtheria and tetanus booster (group 2). Six patients (40%) of group 1 lost protective diphtheria antibodies a median time of 6.5 months after transplant. Thirty-three patients of group 2 responded to the booster with normal diphtheria antibody titers (> 1 IU/mL) in 22 cases and with low titers in 11. Four of the latter lacked immunity to diphtheria at 12 months follow-up. All patients with normal immunity maintained protective levels of diphtheria antibodies. The low responders had a creatinine clearance of 50 +/- 20 mL/min/1.73 m2. Tetanus immunity was maintained in almost all patients of both groups. In conclusion, renal transplant patients had an accelerated loss of diphtheria antibodies in the early post-transplant period. Response to a diphtheria booster identified a group at particular risk, namely the low responders, who may require frequent booster doses. This group had significantly poorer renal function than the normal responders.

Immunity to poliomyelitis, diphtheria and tetanus in pediatric patients before and after renal or liver transplantation.

Few studies have considered the safety, efficacy and appropriateness of vaccinations in pediatric patients before and after solid organ transplantation. The aim of this study was to evaluate the immune status after primary vaccination to diphtheria, tetanus and poliomyelitis in pediatric patients before and after hepatic transplantation and to poliomyelitis in pediatric patients before and after renal transplantation. All the patients had received a complete primary immunization schedule for diphtheria and tetanus and poliomyelitis. Immunity to the three polioviruses was evaluated in 56 patients with renal transplant, 27 on chronic dialysis and 33 controls and in 39 patients with hepatic transplant, 25 with chronic hepatic failure and their 36 controls. Immunity to diphtheria and tetanus was evaluated in 52 liver transplant patients, 29 children with chronic hepatic failure and 54 healthy children. Renal transplant patients were less protected and had lower antibody geometric mean titers than healthy controls for polioviruses 1 and 2. Whereas, protection in the children liver transplant patients was similar to that in their controls. Patients with chronic hepatic failure had higher antibody geometric mean titers to diphtheria and polioviruses 1 and 3 than their control group. Immunosuppression after transplantation has a negative influence on the immune status after primary vaccination in children with renal transplant. Whereas children with chronic hepatic failure have higher antibodies than a normal population. When possible, it could be advisable to individualize immunization schedules in patients at high risk.