Maternal behaviours and adult offspring behavioural deficits are predicted by maternal TNFα concentration in a rat model of neurodevelopmental disorders

Exposure to inflammatory stressors during fetal development is a major risk factor for neurodevelopmental disorders (NDDs) in adult offspring. Maternal immune activation (MIA), induced by infection, causes an acute increase in pro-inflammatory cytokines which can increase the risk for NDDs directly by inducing placental and fetal brain inflammation, or indirectly through affecting maternal care behaviours thereby affecting postnatal brain development. Which of these two potential mechanisms dominates in increasing offspring risk for NDDs remains unclear. Here, we show that acute systemic maternal inflammation induced by the viral mimetic polyinosinic:polycytidylic acid (poly I:C) on gestational day 15 of rat pregnancy affects offspring and maternal behaviour, offspring cognition, and expression of NDD-relevant genes in the offspring brain. Dams exposed to poly I:C elicited an acute increase in the pro-inflammatory cytokine tumour necrosis factor (TNF; referred to here as TNFα), which predicted disruption of key maternal care behaviours. Offspring of poly I:C-treated dams showed early behavioural and adult cognitive deficits correlated to the maternal TNFα response, but, importantly, not with altered maternal care. We also found interacting effects of sex and treatment on GABAergic gene expression and DNA methylation in these offspring in a brain region-specific manner, including increased parvalbumin expression in the female adolescent frontal cortex. We conclude that the MIA-induced elevation of TNFα in the maternal compartment affects fetal neurodevelopment leading to altered offspring behaviour and cognition. Our results suggest that a focus on prenatal pathways affecting fetal neurodevelopment would provide greater insights into the mechanisms underpinning the TNFα-mediated genesis of altered offspring behaviour and cognition following maternal inflammation.

Estimating distribution of hidden objects with drones: from tennis balls to manatees

Unmanned aerial vehicles (UAV), or drones, have been used widely in military applications, but more recently civilian applications have emerged (e.g., wildlife population monitoring, traffic monitoring, law enforcement, oil and gas pipeline threat detection). UAV can have several advantages over manned aircraft for wildlife surveys, including reduced ecological footprint, increased safety, and the ability to collect high-resolution geo-referenced imagery that can document the presence of species without the use of a human observer. We illustrate how geo-referenced data collected with UAV technology in combination with recently developed statistical models can improve our ability to estimate the distribution of organisms. To demonstrate the efficacy of this methodology, we conducted an experiment in which tennis balls were used as surrogates of organisms to be surveyed. We used a UAV to collect images of an experimental field with a known number of tennis balls, each of which had a certain probability of being hidden. We then applied spatially explicit occupancy models to estimate the number of balls and created precise distribution maps. We conducted three consecutive surveys over the experimental field and estimated the total number of balls to be 328 (95%CI: 312, 348). The true number was 329 balls, but simple counts based on the UAV pictures would have led to a total maximum count of 284. The distribution of the balls in the field followed a simulated environmental gradient. We also were able to accurately estimate the relationship between the gradient and the distribution of balls. Our experiment demonstrates how this technology can be used to create precise distribution maps in which discrete regions of the study area are assigned a probability of presence of an object. Finally, we discuss the applicability and relevance of this experimental study to the case study of Florida manatee distribution at power plants.

Phase II Study of Paclitaxel in Patients With Soft Tissue Sarcomas

Purpose. Patients with soft tissue sarcoma (STS) who have previously received standard chemotherapy including adriamycin (doxorubicin), ifosfamide, cyclophosphamide and DTIC (dacarbazine) have very limited therapeutic options. It is important to identify new drugs with some activity in this disease and we therefore undertook this trial to determine the antitumor activity of paclitaxel (Taxol).Methods. We conducted a phase II study of paclitaxel in patients with STS who had received prior standard chemotherapy. Paclitaxel was administered at a starting dose of 200 mg m(-2) as a 24-h infusion with STS premedication, every 21 days or upon hematologic recovery (absolute granulocyte count (AGC) >/= 1500/mul, platelets >/= 100 000/mul). Neupogen was not used routinely. The study was conducted based on a two-stage design proposed by Simon. Responses were assessed radiographically using standard criteria.Results. Nineteen eligible patients were treated in the first stage of the study. The median age was 50 years (range 20-68 years), and there were nine females and 10 males with Zubrod performance status of 1 or 2. One patient achieved a minor response. Median AGC nadir was 0.1/mul on day 12 with absolute neutropenia lasting 5 days. Median platelet nadir was 171 000/mul on day 9. There were no grade 3/4 non-hematologic toxicities and no deaths related to treatment.Discussion. Paclitaxel, at this dose and schedule, is well tolerated but inactive in this patient population.

Varicella vaccination in Australia

Varicella zoster virus (VZV) causes both chickenpox and herpes zoster and is responsible for a significant disease burden, including hospitalizations and deaths, in Australian children and adults. Varicella vaccine has been available in Australia for 5 years; however, from November 2005, it will be funded for use in all susceptible children at 18 months and 10-13 years of age under the National Immunisation Program. Experience with universal varicella vaccination of children in the USA over the last 10 years has shown that the vaccine is safe and highly effective in reducing varicella-related disease. This review summarizes the epidemiology of VZV-related disease in Australia, the use of varicella vaccine and the international experience with vaccine efficacy and safety. The potential impact of varicella vaccination on the incidence of herpes zoster is also discussed.

The seroepidemiology and transmission dynamics of varicella in Australia

To enhance our understanding of the epidemiology and transmission dynamics of varicella in the pre-vaccine era we performed a serosurvey using opportunistically collected sera submitted to diagnostic laboratories across Australia during 1997-1999. A representative sample by state and sex of 2027 sera from persons aged 1-49 years was tested using an enzyme immunoassay method. The average age of infection and age-specific forces of infection (the probability that a susceptible individual acquires infection) were calculated using published methodologies. Seropositivity increased with age, with 83% of sera positive by ages 10-14 years. The highest force of infection was in the 5-9 years age group (0.195 per susceptible year) followed by the 0-4 years age group (0.139 per susceptible year) and the average age of infection was 8.15 years. These results provide valuable baseline information to measure the impact of vaccination and indicate that vaccination should be aimed at children less than 5 years of age, although further modelling using the serosurvey data is warranted.

Use of hospitalization and pharmaceutical prescribing data to compare the prevaccination burden of varicella and herpes zoster in Australia

The aims of the study were to compare the burden of varicella and herpes zoster in Australia. No national surveillance exists for varicella or herpes zoster. We used hospital morbidity data from 1993-9 and pharmaceutical prescribing data from 1995-9. In the financial year 1998/99, there were 4718 hospitalizations for zoster compared to 1991 for varicella. For varicella the mean age of patients was 15 years compared to 69 years for zoster. The mean length of stay in hospital was 4.2 days for varicella and 12.7 days for zoster. Varicella accounted for 8396 (3726 with principal diagnosis varicella) bed days compared to 26 266 (5382 with principal diagnosis of zoster) for zoster. The in-hospital case-fatality rate was 0.4% for varicella and 1% for zoster. In 1999, 59 200 community-based cases of zoster were treated with antivirals. We estimate that 157 266 cases of zoster occurred in the community in 1999, a rate of 830 per 100 000 population. Herpes zoster has a higher burden of disease than varicella, and must be a component of disease surveillance in order to determine the full impact of vaccination on the epidemiology of varicella zoster virus (VZV).

Hepatitis A vaccination options for Australia

The epidemiology of hepatitis A is changing, with an increasing proportion of the population becoming susceptible to infection. The burden of hepatitis A is comparable to that of other vaccine-preventable diseases for which new vaccines are available. Options for vaccination include selective programmes for high-risk groups, which could involve screening prior to vaccination, or universal programmes for infants and/or adolescents. Selective programmes have been shown to be highly cost-effective if well implemented, but there is evidence that they might be poorly implemented. If a universal vaccination programme were considered for Australia, an infant programme, with doses at 18 months and 2 years, possibly with an additional adolescent programme, would be the recommended option. Universal hepatitis A vaccination for infants and/or adolescents is of comparable cost-effectiveness compared with other preventive strategies, but needs to be considered in the context of competing vaccination options.

National study of adverse reactions after vaccination with bacille Calmette-Guérin

Few large prospective studies of adverse reactions after bacille Calmette-Guérin (BCG) vaccination are available. In a prospective national study of such adverse reactions among 918 subjects (aged 1 day to 54 years) over a 14-month period, 45 vaccinees (5%) reported 53 adverse reactions (23 injection-site abscesses, 14 severe local reactions, 10 cases of lymphadenitis, and 6 other reactions). Only 1% of vaccinees required medical attention. Reactions, particularly lymphadenitis, were significantly less common in infants <6 months old (but not in subjects aged > or =6 months) vaccinated by trained (vs. untrained) providers (relative risk [RR], 0.24; 95% confidence interval [CI], 0.09-0.68). Injection-site abscesses (RR, 2.96; 95% CI, 1.11-7.90) and severe local reactions (RR, 4.93; 95% CI, 1.11-21.90) were significantly more common in older vaccinees. Local reactions were more frequently reported by adult females than by adult males (RR, 7.18; 95% CI, 1.59-32.45). Adverse reactions were not significantly associated with any currently available vaccine batch, previous receipt of BCG vaccine, or concomitant administration of other vaccines.

Impact of the Australian Measles Control Campaign on immunity to measles and rubella

To evaluate the impact of the 1998 Australian Measles Control Campaign on immunity to measles and rubella, 4400 opportunistically-collected sera, submitted to diagnostic laboratories across Australia from subjects aged 1-49 years, and 3000 from subjects aged 1-18 years, were tested before and after the campaign, respectively. The proportion of individuals aged 1-18 years who were immune to measles rose from 85% before, to 90% after, the campaign (P < 0.001). The greatest increase was in preschool (7%, P < 0.001) and primary school (10%, P < 0.001) children, who were actively targeted by the campaign. Rubella immunity in 1-18 year-olds rose from 83% to 91% (P < 0.0001), again with significant increases in preschool (4%, P = 0.002) and primary school (16%, P < 0.001) children. 94% of individuals aged 19-49 years were immune to rubella. These serosurveys confirm other evidence of the effectiveness of the Australian Measles Control Campaign and demonstrate the value of serosurveillance using opportunistically collected sera.

Concurrent ifosfamide-based chemotherapy and irradiation. Analysis of treatment-related toxicity in 43 patients with sarcoma

BACKGROUND

The current study was performed to evaluate the toxicity profile of therapeutic doses of ifosfamide (IFX) given concurrently with full-dose external beam radiotherapy (EBRT) in patients with soft tissue and bone sarcomas.

METHODS

The medical records of 43 consecutive patients with soft tissue or bone sarcomas who were treated with concurrent IFX and EBRT were reviewed.

RESULTS

The median patient age was 20 years. Histologies were rhabdomyosarcoma (n = 16 patients), Ewing sarcoma (n = 10 patients), malignant fibrous histiocytoma (n = 9 patients), and other soft tissue sarcomas (n = 8 patients). Thirty-one patients (72%) had localized disease, and 12 patients (28%) had synchronous local and distant disease. Treatment consisted of EBRT (median dose, 50.4 gray [Gy]) with concomitant IFX (median dose per cycle, 10.2 g/m(2)). All patients with Ewing sarcoma or rhabdomyosarcoma received additional concurrent chemotherapy. Twenty-six patients (60%) received two or more cycles of IFX, and 17 patients (40%) were treated with one cycle of IFX and EBRT. The incidences of World Health Organization Grade 3 and Grade 4 toxicities were 29% (21 of 73 cycles) and 22% (16 of 73 cycles), respectively. Grade 4 systemic toxicities included leukopenia (n = 14 patients), neurotoxicity (suicidal ideation; n = 1 patient), and diarrhea (n = 1 patient). Confluent moist desquamation (Grade 3) occurred in nine patients in the treatment field; no patient experienced Grade 4 local toxicity. Among 14 patients who were treated preoperatively, 2 patients (14%) had a pathologic complete response, and 6 patients (43%) had a pathologic near-complete response (> or = 90% necrosis).

CONCLUSIONS

Local and systemic toxicities after the administration of therapeutic doses of IFX with concomitant EBRT appear comparable to those observed with either treatment alone. These results support the design of prospective studies evaluating concurrent ifosfamide and radiation therapy for patients with sarcomas.

Comparative immunogenicity and safety of two dosing schedules of a combined hepatitis A and B vaccine in healthy adolescent volunteers: an open, randomised study

An open, randomised study was undertaken to demonstrate the equivalence in immunogenicity and to determine the reactogenicity and safety of two dosing schedules (0, 6 or 0, 12 month) of an adult formulation of a combined hepatitis A and B vaccine containing 720 EL.U. of inactivated hepatitis A antigen and 20 microg of hepatitis B surface antigen (Twinrix, SmithKline Beecham Biologicals, Belgium) in 240 healthy volunteers aged 12-15 years. The vaccine was well tolerated when administered using either vaccination schedule. At month 7, 98.1% of subjects completing the 0, 6 month vaccination schedule were seroprotected against hepatitis B (anti-hepatitis B surface antigen (anti-HBs) > or =10 mIU/ml) and 100% were seropositive for anti-hepatitis A virus (anti-HAV) antibodies (i.e., > or =33 mIU/ml). The corresponding geometric mean titres (GMTs) were 2791 mIU/ml for anti-HBs and 5992 mIU/ml for anti-HAV antibodies. At month 13, 97% of subjects assigned to the 0, 12 month vaccination schedule were protected against hepatitis B and 99% were seropositive for anti-HAV antibodies. The corresponding GMTs were 4340 and 8472 mIU/ml, respectively. A combined response (i.e., subjects, who were seropositive for anti-HAV antibodies and seroprotected for anti-HBs antibodies) was achieved in 98% of subjects vaccinated according to the 0, 6 month interval and in 96% of subjects vaccinated using the 0, 12 month schedule. The reactogenicity of both vaccination schedules was also equivalent. The results thus show that the combined hepatitis A and B vaccine can be administered using flexible vaccination intervals, which make it suitable for use in large-scale hepatitis immunisation programmes.

Phase II clinical investigation of gemcitabine in advanced soft tissue sarcomas and window evaluation of dose rate on gemcitabine triphosphate accumulation

PURPOSE

To evaluate the efficacy, toxicity, and optimal dose rate of gemcitabine in adult patients with advanced soft tissue sarcomas (STS) by comparing levels of gemcitabine triphosphate (GTP) in peripheral-blood mononuclear cells (PBMCs) of patients receiving two different dose rates.

PATIENTS AND METHODS

Fifty-six assessable patients with STS (17 gastrointestinal [GI] leiomyosarcomas and 39 other histologies) were treated on a two-arm phase II study. Gemcitabine was given at 1 g/m2 as a 30-minute infusion weekly for up to 7 weeks followed by 1 week of rest and reassessment of tumor. Subsequent cycles were given at 1 g/m2 weekly for 3 weeks followed by 1 week of rest. Nine patients underwent cellular pharmacologic studies at two different dose rates (1 g/m2 over a standard 30-minute infusion on week 1 and over pharmacologically based infusion of 150 minutes on week 2) to evaluate GTP levels in PBMCs.

RESULTS

Seven partial responses were noted among 39 patients, for an overall response rate of 18% (95% confidence interval, 7% to 29%). Median duration of response was 3.5 months (range, 2 to 13 months). Four of 10 patients with non-GI leiomyosarcomas achieved a partial response. No objective responses were noted in 17 patients with GI leiomyosarcomas. One patient had a mixed response. Median time to progression for all patients (both arms) was 3 months; median survival was 13.9 months. Treatment was generally well tolerated. Comparison of cellular pharmacology demonstrated a significant 1.4-fold increase in the concentration of GTP with the 150-minute infusion.

CONCLUSION

Given the limited therapeutic armamentarium for STS, the activity of gemcitabine is encouraging. Its potential for combination therapy in the salvage setting should be studied with pharmacologically guided fixed dose-rate infusion.

Hepatitis A epidemiology in Australia: national seroprevalence and notifications

OBJECTIVES

To determine hepatitis A seroprevalence and notification rates in Australia in order to inform vaccination policy.

DESIGN

Seroprevalence was determined by cross-sectional survey of opportunistically collected sera; notifications were extracted from the National Notifiable Diseases Surveillance System.

PARTICIPANTS

3,043 serum samples collected in 1998 were obtained from 46 laboratories around Australia. Sample size in each age group was based on expected seroprevalence, and States and Territories were sampled proportionally to their population size. Males and females were equally represented. Notifications were extracted for cases with onset between 1 January 1991 and 31 December 1998.

MAIN OUTCOME MEASURES

Seroprevalence and notifications were analysed by age, sex and State/Territory.

RESULTS

41.1% of serum samples were seropositive for hepatitis A (95% CI, 39.4%-42.9%) (population-weighted seroprevalence, 38.3%). Seroprevalence was significantly associated with increasing age (P<0.001), but did not differ between the sexes (male:female ratio, 1.04:1; 95% CI, 0.95-1.14). However, significantly more notifications were recorded for males than females (male:female ratio, 1.65:1; 95% CI, 1.60-1.70). The Northern Territory had the highest seroprevalence (68.8%; 95% CI, 52.7%-84.8%) and annual notification rates (48.7 per 100,000 population; 95% CI, 45.0-52.4 per 100,000).

CONCLUSIONS

These data show that about half the Australian population has not been exposed to hepatitis A and is therefore susceptible to infection. However, any decision on national routine childhood hepatitis A vaccination requires a cost-benefit analysis. Routine vaccination of high-incidence communities remains controversial.

The Australian Measles Control Campaign, 1998

The 1998 Australian Measles Control Campaign had as its aim improved immunization coverage among children aged 1-12 years and, in the longer term, prevention of measles epidemics. The campaign included mass school-based measles-mumps-rubella vaccination of children aged 5-12 years and a catch-up programme for preschool children. More than 1.33 million children aged 5-12 years were vaccinated at school: serological monitoring showed that 94% of such children were protected after the campaign, whereas only 84% had been protected previously. Among preschool children aged 1-3.5 years the corresponding levels of protection were 89% and 82%. During the six months following the campaign there was a marked reduction in the number of measles cases among children in targeted age groups.

A short history of vaccination in Australia

It is almost 50 years since infant vaccination for diphtheria, pertussis and tetanus became routine in Australia. Since then, the incidence of vaccine-preventable diseases has declined dramatically. We have used existing records and the recollections of experts to compile a history of vaccination in Australia, focusing on vaccines in the current childhood schedule.

A randomized trial of two acellular pertussis vaccines (dTpa and pa) and a licensed diphtheria-tetanus vaccine (Td) in adults

A single blinded randomized controlled trial to compare the reactogenicity and immunogenicity of adult formulated dTpa and monovalent pa vaccines with a licensed Td vaccine. Five hundred and forty-eight healthy adults aged 19-70 years received a single injection of dTpa or separate injections of pa or Td (with the alternate vaccine 1 month later). Local and systemic reactions were monitored for 15 days after each vaccination. Serum antibody levels were measured immediately prior to and 1 month after vaccination. Antibody levels were measured 12 months after vaccination in 100 subjects. There was no difference in the total frequency of symptoms and signs between subjects receiving any of the three vaccines. There was a significantly lower incidence of local reactions following pa (60%) than dTpa (80%, P=0.002) or Td (93%, P=0.0008). The incidence of clinically significant (Grade 2 or 3) swelling (> or =20 mm) was higher for Td (20%, P=0.002) than for dTpa (11%) or for pa (2%), however, there were no other significant differences in the incidence of Grade 2 or 3 reactions between the vaccines. A high anti-pertussis seroconversion rate (>97%) against all the studied pertussis antigens was seen 1 month after vaccination with dTpa and pa. A total of 96 and 99% of subjects receiving dTpa and Td, respectively, had anti-diphtheria titres > or =0.01 IU/ml, and all but one subject had anti-tetanus titres > or =0.1 IU/ml after 1 month. Twelve months after vaccination the majority (90-100%) of the subjects were still seropositive for each antigen and although GMTs had decreased they were substantially higher than pre-vaccination levels. The dTpa vaccine was well tolerated and capable of eliciting an immune response against all the antigens in a broad spectrum of the adult population and could potentially replace Td for routine boosters in adults.

Impact of neoadjuvant chemotherapy on postoperative morbidity in soft tissue sarcomas

PURPOSE

The purpose of this study was to test the hypothesis that neoadjuvant chemotherapy (NeoCT) does not increase morbidity in patients undergoing radical surgery for soft tissue sarcomas.

PATIENTS AND METHODS

The records of 309 patients who presented to The University of Texas M.D. Anderson Cancer Center for definitive surgical management of primary soft tissue sarcomas were retrospectively reviewed. One hundred five patients who received NeoCT were compared with 204 patients who had surgery first (Surg). Patients had extremity sarcomas (71 NeoCT patients and 130 Surg patients) or retroperitoneal/visceral sarcomas (34 NeoCT and 74 Surg).

RESULTS

NeoCT patients had larger tumors (median, 12 v 8 cm), more frequently had high-grade tumors (90% v 64%), and were younger (median age 47 v 55 years). The incidence of surgical complications was not different for NeoCT patients than for Surg patients, both in those with extremity sarcomas (34% v 41%) and in those with retroperitoneal/visceral sarcomas (29% v 34%). The most common complications were wound infections and other wound complications. Preoperative radiation therapy, autologous flap coverage, and extremity tumors were associated with increased wound complications. No significant differences in length of hospital stay, rate of readmission, or rate of reoperation for complications were found between the NeoCT and Surg groups. One of the three postoperative deaths in our series occurred in the NeoCT group.

CONCLUSION

In this retrospective review, there was no evidence that NeoCT increased postoperative morbidity in patients with soft tissue sarcomas. Prospective, randomized studies are needed to confirm these results.

A statewide survey of general practitioners in NSW, Australia, about immunisation and strategies to increase childhood immunisation rates

A statewide survey was conducted to ascertain GPs' views in New South Wales (NSW), Australia, about the potential usefulness of strategies to increase immunisation rates and to facilitate providing childhood immunisation in their practice. The survey also explored the usefulness of information sources about immunisation. From September 1997-January 1998, a cross-sectional study using a four page self-administered questionnaire was undertaken. Four hundred GPs practising in NSW, Australia were randomly selected and 343 were eligible to participate. Of these, 281 returned a completed questionnaire (82% response rate). Ninety-one percent and 88% of GPs, respectively, agreed that television campaigns or registering children with the national Australian Childhood Immunisation Register (ACIR) were likely to increase immunisation rates. Sixty-two percent of respondents considered that the media created unwarranted parental concern about immunisation. GPs most commonly rated availability of an ACIR list of children overdue for immunisation, better parent educational material and better access to vaccines as strategies which would make immunisation easier. Sixty percent of respondents felt that increased GP payments would be successful in increasing immunisation rates. Only 51% indicated that they had used the "Australian Immunisation Procedures Handbook 6th edition" (a national clinical practice guideline) in the previous month. This study identified GP support for many initiatives aimed at increasing immunisation rates in Australia although GPs were sceptical about the benefits of some programmes. Studies to monitor the impact of GP incentives on immunisation rates in populations and individual practices are underway. These will be useful in determining whether GPs' opinions found in our study correlate with practice in this regard.

Pneumococcal disease in Australia

The proceedings of the Pneumococcal Disease in Australia Workshop, held on 26-27 March 1999 are presented in this report. The world-wide epidemiology of the pneumococcus, with its predilection for the very young and the very old, differs between the developing and the developed world, and between indigenous and non-indigenous populations. Sources of data on pneumococcal disease in each of the Australian States, clinical aspects of invasive and non-invasive disease, and the role of the public health laboratory in surveillance of serotypes and antimicrobial sensitivity, both nationally and over time, were discussed at the Workshop. Polysaccharide pneumococcal vaccines are recommended for those over 65 years of age and for at-risk groups, but are supplied free of charge only in Victoria and for indigenous Australians over 50 years of age. Children will require conjugate vaccines, which are likely to be licensed in the United States of America early in 2000. In Australia indigenous children, especially in rural areas, will be the priority group for conjugate vaccines.

Factors influencing vaccination uptake. Workshop report. Current Australian research on the behavioural, social and demographic factors influencing immunisation, Royal Alexandra Hospital for Children, Sydney, March 1998

Current Australian research on factors influencing vaccination was discussed at a workshop held at the Royal Alexandra Hospital for Children, Sydney, in March 1998, sponsored by the National Centre for Immunisation Research and Surveillance of Vaccine Preventable Diseases (NCIRS). The application of decision making theory to vaccination behaviour, the expectations and experiences of mothers, and reasons why parents fail to vaccinate their children were considered. Mothers' perceptions of the risks of vaccines, preferences of parents and providers for the mode of vaccine delivery, and community and social factors were all found to be part of the framework within which vaccination is accepted in Australia. Consumer considerations, media influences and overseas comparisons were discussed.

Vaccination of children following a previous hypotonic-hyporesponsive episode

BACKGROUND

Hypotonic-hyporesponsive episodes (HHE) were once considered a contraindication to pertussis vaccination.

METHODOLOGY

To evaluate the safety of further vaccination, chart review was conducted of 66 children who had experienced an HHE, and who were assessed in one of three special clinics in three capital city tertiary paediatric hospitals. Immediately prior to the HHE, 63 children had received whole-cell pertussis vaccine, three had received acellular pertussis vaccine.

RESULTS

Sixty-four of the 66 children were vaccinated in the special clinic, 59 with pertussis-containing vaccines (55 acellular, four whole-cell), without serious adverse events. There were no HHE after these further vaccinations.

CONCLUSIONS

Previously healthy children who experience HHE reactions can safely continue standard vaccination schedules.

Surgical strategy for the treatment of medullary thyroid carcinoma

OBJECTIVE

To evaluate surgical complications, patterns of lymph node metastases, and calcitonin response to compartment-oriented lymphadenectomy in patients with primary or recurrent medullary thyroid carcinoma (MTC).

SUMMARY BACKGROUND DATA

The majority of patients with invasive MTC have metastasis to regional lymph nodes at the time of diagnosis, as evidenced by the frequent finding of persistently elevated calcitonin levels after thyroidectomy and the high rates of recurrence in the cervical lymph nodes reported in retrospective studies. These data have provided the rationale for surgeons to perform a more extensive lymphadenectomy at the time of initial thyroidectomy and to consider reoperative cervical lymphadenectomy in patients with persistently elevated calcitonin levels after thyroidectomy.

METHODS

Forty patients underwent surgery for MTC from 1991 to 1997 (23 sporadic cases, 17 familial cases). Patients were divided into three groups based on whether they had undergone previous thyroidectomy and on the results of standardized staging studies performed after referral to the authors' institution. Group 1 (11 patients) had received no previous surgery; group 2 (13) underwent thyroidectomy before referral and had an elevated calcitonin level without radiologic evidence of local regional or distant metastases; and group 3 (16) underwent thyroidectomy before referral and had an elevated calcitonin level with radiologic evidence of local-regional recurrence. The central neck compartment was dissected in all patients; preoperative staging and the extent of previous surgery dictated the need for lateral (modified radical) neck dissection. After primary or reoperative surgery, calcitonin levels were assessed.

RESULTS

All patients had major reductions in postoperative calcitonin levels. Seven (29%) of 24 patients in groups 1 and 2 achieved normal calcitonin values compared with only 1 (6%) of 16 in group 3. Postoperative complications included seven cases (17%) of permanent hypoparathyroidism; five (71%) of these occurred in group 3. There were no iatrogenic recurrent laryngeal nerve injuries; one patient required recurrent nerve resection to achieve complete tumor extirpation. At a median follow up of 35 months, local recurrence was documented in 5 (13%) of 40 patients.

CONCLUSIONS

Compartment-oriented lymphadenectomy performed early in the course of MTC is safe and may return calcitonin levels to normal in up to 25% of carefully selected patients. However, reoperation for bulky cervical disease (group 3) rarely results in normal calcitonin levels and is associated with a high incidence of permanent hypoparathyroidism.

The cost-effectiveness of varicella vaccine programs for Australia

OBJECTIVE

to examine the cost-effectiveness of three different varicella vaccination programs compared with no vaccination program.

DESIGN

cost-effectiveness study. Simulations of the costs and consequences of chickenpox and the vaccination programs over a 30-year period. Direct (health-care) costs only were used in the simulations.

SETTING

Australia.Participants/subjects: annual birth cohorts of infants (12-months old) and adolescents (12 years old).

INTERVENTIONS

strategy I (no vaccination) was compared with three different varicella vaccination programs: strategy II - all infants; strategy III - adolescents without a history of varicella; and strategy IV ('catch-up')- all infants plus, for the first 11 years, adolescents without a history.

OUTCOME MEASURES

fatalities and hospitalisations for varicella and its complications (encephalitis, pneumonitis, long-term disability).

RESULTS

the average cost per case of chickenpox averted was $64, $530 and $418 in the infant, adolescent and catch-up programs, respectively. The infant program was the most cost-effective of the three. This program could avert 4. 4 million cases, 13,500 hospitalisations and 30 fatalities for chickenpox over a 30-year period. RESULTS were sensitive to the price of the vaccine and the discount rate, but relatively insensitive to changes in vaccine efficacy, coverage rates or vaccine complication rates. Improved accuracy of a negative varicella history in adolescents would substantially reduce the costs of the adolescent and catch-up programs making these programs feasible.

CONCLUSIONS

the infant vaccine program is the preferred program, but the direct costs of any of the vaccination programs considered here are greater than the direct costs of no vaccination program.

Long-term outcome of patients with American Joint Committee on Cancer stage IIB extremity soft tissue sarcomas

PURPOSE

It has been suggested that patients with small (< 5 cm), high-grade extremity soft tissue sarcomas (STS) have an excellent overall prognosis and, consequently, may not require adjuvant therapies.

PATIENTS AND METHODS

A comprehensive review of all patients with extremity STS treated at a tertiary care cancer hospital over a 9-year period (January 1984 to December 1992) was performed. Prognostic factors, treatment data, and long-term outcome were evaluated in the subset of 111 patients with American Joint Committee on Cancer stage IIB (G3/4, T1a/b) disease.

RESULTS

The median tumor size was 3.0 cm (range, 0.6 to 4.9 cm), and 55 tumors (50%) were deep in location. All patients underwent surgical resection; 68 (61%) received pre- or postoperative radiotherapy, and 32 (29%) received doxorubicin-based chemotherapy. The median follow-up was 76 months. Forty patients (36%) experienced 59 recurrences. First recurrences occurred at local, regional, and distant sites in 21, five, and 14 patients, respectively. The 5-year actuarial local recurrence-free, distant recurrence-free, disease-free, and overall survival rates were 82%, 83%, 68%, and 83%, respectively. The presence of a microscopically positive surgical margin was an independent adverse prognostic factor for both local recurrence (relative risk [RR] = 3.75; 95% confidence interval [CI], 1.25 to 11.25; P =.02) and disease-free survival (RR = 2.57; 95% CI, 1.33 to 4.98; P =.005).

CONCLUSION

Event-free outcome for this subset of patients with high-grade STS does not seem as favorable as previously reported by other investigators. Patients who undergo maximal surgical resection with microscopically positive margins represent a subset of T1 STS patients who warrant consideration for adjuvant therapies.

The epidemiology of rubella and congenital rubella in Australia, 1992 to 1997

Selective rubella vaccination of schoolgirls commenced in 1971 and was followed by a significant reduction in congenital rubella. Infant vaccination with MMR was introduced in 1989 to interrupt circulation of the virus in young children, and in 1994/95 the adolescent school based rubella vaccination program was changed to MMR for both boys and girls. This report reviews the epidemiology of rubella and congenital rubella between 1992 and 1997 using reports to the National Notifiable Diseases Surveillance System (NNDSS) and the Australian Paediatric Surveillance Unit (APSU). Notification rates for rubella exceeded 20 per 100,000 in 1992, 1993 and 1995 and declined to 7.2 per 100,000 in 1997. Sixty-one per cent of notifications occurred between September and December and 68% occurred in males. The incidence rate in males aged 15-22 years peaked at 152.6 per 100,000 in 1995 reflecting the lack of immunisation in this cohort. From 1993 to 1997, 19 children were reported with congenital rubella syndrome, representing 1 in 67,000 live births. Of these, 17 had multiple defects (4 died) and 2 had deafness only. There were also 5 infants with congenital rubella infection but no defects. Australia's rate of congenital rubella syndrome exceeded that of the United Kingdom and the United States of America but this may be partly attributable to differences in reporting practices. The impact of changing the second dose of MMR vaccine to 4 years of age in 1998 will require careful monitoring.

Varicella vaccine in non-immune household contacts of children with cancer or leukaemia

OBJECTIVE

To assess the immunogenicity and reactogenicity of a new formulation of live attenuated varicella vaccine (Oka strain) in non-immune household contacts of children with cancer or leukaemia.

METHODOLOGY

This was an open study with one group. Healthy varicella-susceptible adults and children living in the same household as children with cancer or leukaemia were vaccinated with a new live attenuated varicella vaccine (Oka strain) which is stable when stored at 2-8°C (refrigerator temperature) for at least 24 months (Varilrix). Children less than 13 years of age received one dose (0.5 mL containing at least 10^3.3 plaque forming units) by subcutaneous injection and those aged over 13 years received two doses 8 weeks apart. Adverse reactions following vaccination were recorded daily by the vaccinees. Post-vaccination antibody estimation was determined using indirect immunofluorescence 6 weeks after vaccination.

RESULTS

Thirty-five seronegative subjects (28 children and 7 adults and adolescents) were vaccinated. All subjects tested (34) had seroconverted after vaccination. Local injection site reactions were experienced by 15/35. Other adverse reactions were uncommon (rash 2/35, fever (≥ 37.5°C) 3/35). No cases of clinical varicella occurred amongst the high-risk household contacts of the vaccine.

CONCLUSION

This is the first study of this formulation of varicella vaccine in household contacts of children with cancer or leukaemia. The vaccine was found to be safe and immunogenic, but further follow-up is needed to document duration of immunity.

Immunisation coverage in Australian children: a systematic review 1990-1998

The Australian Childhood Immunisation Register (ACIR) commenced operation in January 1996 and provides a comprehensive database of children's immunisations in Australia. The ACIR enables implementation of an immunisation recall and reminder system and improved surveillance and reporting of immunisation coverage. Before the introduction of the ACIR, the methods used in assessing coverage varied widely in design and quality, with few studies measuring coverage at national or statewide level. This is a systematic review of the scope and reliability of estimates of immunisation coverage available in Australia from 1990 to 1998. A total of 108 studies were identified of which 51 were classified as higher quality based on a range of criteria including whether they had a response rate of 50% or better.

Varicella vaccination of health-care workers

The objective of this open study was to evaluate the response of non-immune health-care workers to two doses of live attenuated varicella vaccine given two months apart. One hundred subjects (58 females; aged 17-49 yr, mean 22.8 yr) received two doses of varicella vaccine. Blood samples for antibody estimation were taken before vaccination, 2 months after the first dose and 6 weeks after the second dose. Reactions were recorded daily in diaries by the vaccinees and controlled by telephone contacts by the investigators. Ninety-four of 99 vaccinees (94.9%, 95% CL 88.6, 98.3) had detectable antibodies after the first dose [titers 4-1024, geometric mean titer (GMT): 53.2 (95% CL 42.4, 66.8)]. After the second dose, all vaccinees had antibodies (100%, 95% CL 96.6, 100.0) [titers 32-2048, GMT: 235.6 (95% CL 199.0, 278.8)]. Mild reactions limited to the injection site occurred in 1 in 4 subjects after each dose. Vesicular rashes occurred in one subject after the 1st dose and in 3 subjects after the 2nd dose, 1 subject was febrile (38.2 degrees C) after the 1st dose. Eighty-one subjects were retested 12 months after the second vaccination. Three had become seronegative (one developed mild varicella 2 months later). Two had boosted their titers (one after mild clinical varicella 1 month earlier, the other after close contact with clinical cases). The GMT of the group had fallen to 83.6 (95% CL 65.4, 106.8). The identification and vaccination of seronegative health-care workers is safe and efficient, and will benefit the workers themselves and the communities in which they work.

Parent and general practitioner preferences for infant immunisation. Reactogenicity or multiple injections?

AIM

To explore the relative importance parents and general practitioners place on less reactogenic vaccines and multiple injections at each childhood immunisation encounter.

METHOD

A random sample of western Sydney parents (n = 162) and GPs (n = 154) completed telephone questionnaires about their preference for either a single injection of pentavalent vaccine (whole-cell pertussis/diphtheria/tetanus/Hib/hepatitis B), or regimen containing the less reactogenic acellular pertussis vaccine requiring two separate injections (acellular pertussis/diphtheria/tetanus and Hib or three separate injections (acellular pertussis/diphtheria/tetanus and Hib and hepatitis B). Potential confounders were examined by univariate and multivariate analysis.

RESULTS

Regimens containing acellular pertussis vaccine (2 injections or 3 injections) were preferred by 72% and 58% of parents respectively. Those whose children were already vaccinated were less concerned about side effects and were twice (or = 2.0, 95% CI 1.0-4.0) as likely to select the pentavalent (single injection) option. 69% and 77% of GPs preferred the pentavalent rather than the two or three injection acellular option, although previous experience with a systemic adverse reaction to immunisation increased their preference for the acellular pertussis vaccine (or = 2.9, 95% CI 1.1-7.6). Only 54% of parents and 28% of GPs favoured three injections at one visit.

CONCLUSION

Parent and GP concerns regarding reactogenicity and multiple injections differ. Parents are more concerned about vaccine reactogenicity than multiple injections. However, if the GP recommends a particular regimen, it is likely to be accepted by parents.

Phase II study of CI-980 (NSC 635370) in patients with previously treated advanced soft-tissue sarcomas

Doxorubicin and ifosfamide are the two most active agents in the treatment of soft-tissue sarcomas. Patients whose tumors have failed these two drugs have very limited systemic therapy options. It is, therefore, important to identify newer drugs with activity against this disease. CI-980 is a synthetic mitotic inhibitor that binds to tubulin at the colchicine binding site and inhibits the polymerization of tubulin and blocks cell cycle progression in mitosis. Given its broad spectrum activity against several solid tumor models in vivo, we decided to perform a phase 2 study of this drug in previously treated soft-tissue sarcomas. A total of 18 eligible and evaluable patients were entered in the first stage of the trial. The median age was 53 yrs (range, 17-72). No objective responses have been noted. Six patients had stable disease after a median of 3.5 cycles of chemotherapy while 12 others had progressive disease. A total of 48 cycles were administered, 42 of which were administered at dose level 0 (4.5 mg/m2/d x 3). The median AGC nadir was 1.2/microl(0.1 -4.7) on day 10 and the median platelet nadir was 150,000/microl (31,000-338,000). Twenty cycles were complicated with grade 3-4 neutropenia and two cycles were complicated with FUO. There were no CNS toxicities. One patient had a grade 1 thrombophlebitis in 2 cycles and one other patient had a grade 4 thrombophlebitis in one cycle. In conclusion, CI-980 was well tolerated at this dose and schedule but inactive in soft-tissue sarcomas.

Varicella-zoster virus infection in Australia

OBJECTIVE

To determine the epidemiology of varicella-zoster virus (VZV) infection in Australia using currently available data sources.

DESIGN

Analysis of national death data (23 years), congenital and neonatal cases (one year) and attendances at sentinel general practices (two years); hospital admissions in NSW and SA (six years); serological studies in 1995 involving antenatal clinics in Sydney and Brisbane and child-care centre staff and refugees in Sydney; and case-ascertainment in 1995 in South Western Sydney among public hospital staff, child-care centre staff and the community.

RESULTS

In Australia, there have been an average of 3.5 deaths from chickenpox (mostly children) and 11 from herpes zoster (mostly older people) each year since 1980. The crude death rate for chickenpox has declined (p > 0.05). In 1995, there were 14 cases of neonatal and two of congenital varicella. Average annual admission rates for NSW and SA showed 1,200 hospital bed-days used for chickenpox, more than 20% with complications, and more than 7,300 bed days for zoster; annually more than 880 in-patient admissions were complicated by VZV. Most people encounter the virus in their first 15 years, but some remain susceptible into their 20s; 25% of cases and 37% of hospital admissions for chickenpox occur in people > or = 15 years of age.

CONCLUSION

VZV infection involves people of all ages. It causes substantial morbidity and mortality, particularly at the extremes of life. The death rate from chickenpox but not zoster has fallen since the introduction of acyclovir in the 1980s. Surveillance of VZV infection must be given priority once vaccines become available, to monitor changes in morbidity and mortality.

Results of two consecutive trials of dose-intensive chemotherapy with doxorubicin and ifosfamide in patients with sarcomas

The authors evaluate the efficacy and feasibility of dose-intensive doxorubicin and ifosfamide combination chemotherapy in patients with sarcomas. From January 1995 to April 1996, 33 evaluable patients with either metastatic sarcoma or primary sarcomas with a high-risk for metastases (all except one was previously untreated with chemotherapy) were treated on two consecutive protocols. The median age was 45 years (range, 15-68 years). The first protocol included doxorubicin at 75 mg/m2 given as a 72-hour infusion on days 1 to 3 along with ifosfamide at 2 g/m2/d over 2 hours x 5, days 1 to 5 (protocol AI 75/10). Granulocyte colony-stimulating factor (G-CSF) was used only if indicated according to American Society of Clinical Oncology guidelines. The second protocol included doxorubicin at 90 mg/m2 as a 72-hour continuous infusion and ifosfamide at 2.5 g/m2/d for 4 days (protocol AI 90/10) with prophylactic G-CSF. A median of four cycles were administered (range, 1-6). Three patients achieved a pathologic complete response (CR) and 18 patients achieved a partial response (PR) for a response rate (RR) of 64% (95% confidence interval (CI), 45-80%). Response rate for the subset of patients with soft-tissue sarcomas was 66% (95% CI, 46-82%). Only three patients progressed on therapy. Febrile neutropenia was noted in 31% of cycles at AI 75/10 and in 56% of cycles at AI 90/10. One patient developed reversible grade 3 central nervous system (CNS) toxicity. There was one treatment-related death on AI 90/10 secondary to doxorubicin cardiac toxicity at a cumulative dose of 435 mg/m2. Dose-intensive doxorubicin plus ifosfamide is feasible in appropriately selected patients and appears to be a very active regimen in patients with sarcomas. The authors are currently testing this regimen with G-CSF and thrombopoietin.

Measles control in Australia. Report of the Measles Control in Australia Workshop, 5 November 1997

The proceedings of the Measles Control in Australia Workshop held on 5 November 1998 are presented in this report. Prompted by the possibility of a global elimination campaign in the near future the Workshop considered the factors involved in elimination of measles from Australia. Epidemiology, surveillance, laboratory diagnosis methods, mathematical modelling, and the cost and logistics were all addressed. Mass vaccination for all 2-18 year olds, and a routine 2-dose regimen with scheduled doses at 12 months and school entry were recommended. Intensified surveillance, based on a sensitive case definition and laboratory confirmation (measles specific IgM) of suspected cases was identified as a crucial component of the campaign. The continuation of high vaccination coverage for each of the two doses would be essential to maintain elimination once established.

Horizontal transmission of hepatitis B in a children's day-care centre: a preventable event

Using molecular finger-printing, we provided evidence that, in a children's day-care centre, a known hepatitis B virus (HBV) hepatitis B e antigen (HBeAg) carrier transmitted HBV to another child (the index case). The chronic HBV carrier had an exudative skin lesion and a history of biting. We sought to identify other at-risk children and prevent further transmission. Blood samples were collected and tested serologically for HBV. Of the 90 other children, 78 (87 per cent) were tested and none had serological evidence of HBV infection; 73 (81 per cent) were of Caucasian background; 38 (49 per cent) had a history of HBV immunisation with serological confirmation. Therefore, 1 (2.4 per cent, 95 per cent confidence interval 1.0 to 12.8 per cent) of the 41 known susceptible contacts became infected. The risk of horizontal HBV transmission in a children's day-care centre is low but not negligible. Staff and children should be vaccinated when a child in a day-care centre is a known HBV carrier.

Rotavirus gastroenteritis: impact on young children, their families and the health care system

OBJECTIVE

To assess the impact of rotavirus gastroenteritis on young children attending a paediatric hospital, their families and the health care system.

DESIGN

Cross-sectional descriptive survey.

SETTING

New Children's Hospital (Royal Alexandra Hospital for Children), Sydney, New South Wales, 15 July to 4 October 1996.

PARTICIPANTS

Children aged under three years attending the Emergency Department with acute diarrhoea as the presenting symptom.

OUTCOME MEASURES

Cases of rotavirus infection confirmed by enzyme-linked immunosorbent assay by age; rotavirus serotype; gastroenteritis severity score; estimated costs to parents (lost pay or leave, travel, medication and other expenses) and to the health care system (visits to Emergency Department and other health care workers, hospital admissions).

RESULTS

280 children were recruited (73% of 384 children who met the inclusion criteria and 27% of the 1037 aged under three years with acute gastroenteritis). Rotavirus was detected in 188 of the 280 (67%); most isolates were serotype G1 (86% of the 174 serotyped). Of the 188 children with confirmed rotavirus infection 78% were aged 7-24 months and 82% visited at least one other health care worker, usually a general practitioner. Seventy (37% of the 188) were admitted to hospital; 33 of these (47%) were aged 13-24 months. Estimated mean total cost per episode of rotavirus gastroenteritis was $1744 for children admitted to hospital and $441 for children not admitted. The mean cost to families was $493 for children admitted to hospital and $228 for children not admitted.

CONCLUSIONS

Rotavirus gastroenteritis has a significant impact on young children, their families and the health care system. Prevention of severe disease through routine infant vaccination would be potentially cost-effective.