The effectiveness of maternal pertussis vaccination for protecting Aboriginal and Torres Strait Islander infants against infection, 2012-2017: a retrospective cohort study

OBJECTIVES

To evaluate the effectiveness of maternal pertussis vaccination for preventing pertussis infections in Aboriginal and Torres Strait Islander infants under seven months of age.

STUDY DESIGN

Retrospective cohort study; analysis of linked administrative health data.

SETTING, PARTICIPANTS

Mother-infant cohort (Links2HealthierBubs) including all pregnant women who gave birth to live infants (gestational age ≥ 20 weeks, birthweight ≥ 400 g) in the Northern Territory, Queensland, and Western Australia during 1 January 2012 - 31 December 2017.

MAIN OUTCOME MEASURES

Proportions of women vaccinated against pertussis during pregnancy, rates of pertussis infections among infants under seven months of age, and estimated effectiveness of maternal vaccination for protecting infants against pertussis infection, each by Indigenous status.

RESULTS

Of the 19 892 Aboriginal and Torres Strait Islander women who gave birth to live infants during 2012-2017, 7398 (37.2%) received pertussis vaccine doses during their pregnancy, as had 137 034 of 259 526 non-Indigenous women (52.8%; Indigenous v non-Indigenous: adjusted odds ratio, 0.66; 95% confidence interval [CI], 0.62-0.70). The annual incidence of notified pertussis infections in non-Indigenous infants declined from 16.8 (95% CI, 9.9-29) in 2012 to 1.4 (95% CI, 0.3-8.0) cases per 10 000 births in 2017; among Aboriginal and Torres Strait Islander infants, it declined from 47.6 (95% CI, 16.2-139) to 38.6 (95% CI, 10.6-140) cases per 10 000 births. The effectiveness of maternal vaccination for protecting non-Indigenous infants under seven months of age against pertussis infection during 2014-17 was 68.2% (95% CI, 51.8-79.0%); protection of Aboriginal and Torres Strait Islander infants was not statistically significant (36.1%; 95% CI, -41.3% to 71.1%).

CONCLUSIONS

During 2015-17, maternal pertussis vaccination did not protect Aboriginal and Torres Strait Islander infants in the NT, Queensland, and WA against infection. Increasing the pertussis vaccination rate among pregnant Aboriginal and Torres Strait Islander women requires culturally appropriate, innovative strategies co-designed in partnership with Indigenous organisations and communities.

Maternal Pertussis Vaccination, Infant Immunization, and Risk of Pertussis

OBJECTIVES

Following the introduction of jurisdictional maternal pertussis vaccination programs in Australia, we estimated maternal vaccine effectiveness (VE) and whether maternal pertussis vaccination modified the effectiveness of the first 3 primary doses of pertussis-containing vaccines.

METHODS

We conducted a population-based cohort study of 279 418 mother-infant pairs using probabilistic linkage of administrative health records in 3 Australian jurisdictions. Infants were maternally vaccinated if their mother had a documented pertussis vaccination ≥14 days before birth. Jurisdictional immunization records were used to identify receipt of the first 3 infant doses of pertussis-containing vaccines. Infant pertussis infections were identified using notifiable disease records. VE was estimated using Cox proportional hazard models.

RESULTS

Pertussis was administered during 51.7% (n = 144 429/279 418) of pregnancies, predominantly at 28-31 weeks' gestation. VE of maternal pertussis vaccination declined from 70.4% (95% confidence interval [CI], 50.5-82.3) among infants <2 months old to 43.3% (95% CI, 6.8-65.6) among infants 7-8 months old and was not significant after 8 months of age. Although we observed slightly lower VE point estimates for the third dose of infant pertussis vaccine among maternally vaccinated compared with unvaccinated infants (76.5% vs 92.9%, P = .002), we did not observe higher rates of pertussis infection (hazard ratio, 0.70; 95% CI, 0.61-3.39).

CONCLUSIONS

Pertussis vaccination near 28 weeks' gestation was associated with lower risk of infection among infants through 8 months of age. Although there was some evidence of lower effectiveness of infant vaccination among maternally vaccinated infants, this did not appear to translate to greater risk of disease.

Factors Predicting Secondary Respiratory Morbidity Following Early-Life Respiratory Syncytial Virus Infections: Population-Based Cohort Study

Background

The association between early-life respiratory syncytial virus (RSV) infections and later respiratory morbidity is well established. However, there is limited evidence on factors that influence this risk. We examined sociodemographic and perinatal factors associated with later childhood respiratory morbidity requiring secondary care following exposure to a laboratory-confirmed RSV episode in the first 2 years.

Methods

We used a probabilistically linked whole-of-population-based birth cohort including 252 287 children born in Western Australia between 2000 and 2009 with follow-up to the end of 2012. Cox proportional hazards models estimated adjusted hazard ratios (aHRs) of the association of various risk factors with the first respiratory episode for asthma, wheezing, and unspecified acute lower respiratory infection beyond the age of 2 years.

Results

The analytic cohort included 4151 children with a confirmed RSV test before age 2 years. The incidence of subsequent respiratory morbidity following early-life RSV infection decreased with child age at outcome (highest incidence in 2-<4-year-olds: 41.8 per 1000 child-years; 95% CI, 37.5-46.6), increased with age at RSV infection (6-<12-month-olds: 23.6/1000 child-years; 95% CI, 19.9-27.8; 12-<24-month-olds: 22.4/1000 child-years; 95% CI, 18.2-22.7) and decreasing gestational age (50.8/1000 child-years; 95% CI, 33.5-77.2 for children born extremely preterm, <28 weeks gestation). Risk factors included age at first RSV episode (6-<12 months: aHR, 1.42; 95% CI, 1.06-1.90), extreme prematurity (<28 weeks: aHR, 2.22; 95% CI, 1.40-3.53), maternal history of asthma (aHR, 1.33; 95% CI, 1.04-1.70), and low socioeconomic index (aHR, 1.76; 95% CI, 1.03-3.00).

Conclusions

Our results suggest that in addition to preterm and young infants, children aged 12-<24 months could also be potential target groups for RSV prevention to reduce the burden of later respiratory morbidities associated with RSV.

Determining the true incidence of seasonal respiratory syncytial virus-confirmed hospitalizations in preterm and term infants in Western Australia

Respiratory syncytial virus contributes to significant global infant morbidity and mortality. We applied a previously developed statistical prediction model incorporating pre-pandemic RSV testing data and hospital admission data to estimate infant RSV-hospitalizations by birth month and prematurity, focused on infants aged <1 year. The overall predicted RSV-hospitalization incidence rates in infants <6 months were 32.7/1,000 child-years (95 % CI: 31.8, 33.5) and 3.1/1,000 child-years (95 % CI: 3.0, 3.1) in infants aged 6-<12 months. Predicted RSV-hospitalization rates for infants aged <6 months were highest for infants born in April/May. Predicted rates for preterm infants born 29-32 weeks gestation were highest in March-May, whereas infants born >33 weeks had peak RSV-hospitalization rates from May-June, similar to late preterm or term births. RSV-hospitalization rates in the pre-pandemic era were highly seasonal, and seasonality varied with degree of prematurity. Accurate estimates of RSV-hospitalization in high-risk sub-groups are essential to understand preventable burden of RSV especially given the current prevention landscape.

Association between maternal influenza vaccination and neurodevelopmental disorders in childhood: a longitudinal, population-based linked cohort study

OBJECTIVE

To assess the association between in utero exposure to seasonal inactivated influenza vaccine (IIV) and the risk of a diagnosis of a neurodevelopmental disorder in early childhood.

DESIGN

Retrospective cohort study.

SETTING

Population-based birth registry linked with health administrative databases in Western Australia (WA).

PARTICIPANTS

Singleton, liveborn children born between 1 April 2012 and 1 July 2016 in WA.

EXPOSURE

Receipt of seasonal IIV during pregnancy obtained from a state-wide antenatal vaccination database.

MAIN OUTCOME MEASURES

Clinical diagnosis of a neurodevelopmental disorder was recorded from hospital inpatient and emergency department records. We used Cox proportional hazard regression, weighted by the inverse-probability of treatment (vaccination), to estimate the hazard ratio (HR) of neurodevelopmental disorders associated with in utero exposure to seasonal IIV.

RESULTS

The study included 140 514 children of whom, 15 663 (11.2%) were exposed to seasonal IIV in utero. The prevalence of neurodevelopmental disorders was 5.4%, including mental or behavioural (0.4%), neurological (5.1%), seizure (2.2%) and sleep disorders (2.7%). Maternal IIV was not associated with increased risk of neurodevelopmental disorders (HR 1.00; 95% CI 0.91 to 1.08). Children exposed in the first trimester had a lower risk of seizure disorders (adjusted HR [aHR] 0.73; 95% CI 0.54 to 0.998), and preterm children exposed any time during pregnancy had a lower risk of sleep disorders (aHR 0.63; 95% CI 0.41 to 0.98).

CONCLUSIONS

We did not observe increased risk of neurodevelopmental disorders following in utero exposure to seasonal IIV. Although we observed some evidence for lower risk of seizure and sleep disorders, additional studies are required to confirm.

Inequity of antenatal influenza and pertussis vaccine coverage in Australia: the Links2HealthierBubs record linkage cohort study, 2012-2017

BACKGROUND

Pregnancy and early infancy are increased risk periods for severe adverse effects of respiratory infections. Aboriginal and/or Torres Strait Islander (respectfully referred to as First Nations) women and children in Australia bear a disproportionately higher burden of respiratory diseases compared to non-Indigenous women and infants. Influenza vaccines and whooping cough (pertussis) vaccines are recommended and free in every Australian pregnancy to combat these infections. We aimed to assess the equity of influenza and/or pertussis vaccination in pregnancy for three priority groups in Australia: First Nations women; women from culturally and linguistically diverse (CALD) backgrounds; and women living in remote areas or socio-economic disadvantage.

METHODS

We conducted individual record linkage of Perinatal Data Collections with immunisation registers/databases between 2012 and 2017. Analysis included generalised linear mixed model, log-binomial regression with a random intercept for the unique maternal identifier to account for clustering, presented as prevalence ratios (PR) and 95% compatibility intervals (95%CI).

RESULTS

There were 445,590 individual women in the final cohort. Compared with other Australian women (n = 322,848), First Nations women (n = 29,181) were less likely to have received both recommended antenatal vaccines (PR 0.69, 95% CI 0.67-0.71) whereas women from CALD backgrounds (n = 93,561) were more likely to have (PR 1.16, 95% CI 1.10-1.13). Women living in remote areas were less likely to have received both vaccines (PR 0.75, 95% CI 0.72-0.78), and women living in the highest areas of advantage were more likely to have received both vaccines (PR 1.44, 95% CI 1.40-1.48).

CONCLUSIONS

Compared to other groups, First Nations Australian families, those living in remote areas and/or families from lower socio-economic backgrounds did not receive recommended vaccinations during pregnancy that are the benchmark of equitable healthcare. Addressing these barriers must remain a core priority for Australian health care systems and vaccine providers. An extension of this cohort is necessary to reassess these study findings.

Timing and temporal trends of influenza and pertussis vaccinations during pregnancy in three Australian jurisdictions: The Links2HealthierBubs population-based linked cohort study, 2012-2017

BACKGROUND

Antenatal inactivated influenza (IIV) and pertussis-containing vaccines (dTpa) offer protection against severe respiratory infections for pregnant women and infants <6 months of age. Both vaccines are recommended in pregnancy; however, little is known about temporal or jurisdictional trends and predictors of uptake.

AIMS

To identify gaps and predictors of IIV and/or dTpa vaccinations in Australian pregnancies from 2012 to 2017.

MATERIALS AND METHODS

We conducted a probabilistically linked, multi-jurisdictional population-based cohort study, drawing from perinatal data collections and immunisation databases. We used a generalised linear mixed model with a random effect term to account for clustering of multiple pregnancies within mothers, to calculate vaccination uptake, and identify predictors of uptake by maternal demographic, pregnancy, and health characteristics.

RESULTS

Of 591 868 unique pregnancies, IIV uptake was 15%, dTpa 27% and 12% received both vaccines. Pertussis vaccinations in First Nations pregnancies were 20% lower than non-Indigenous pregnancies; dTpa was strongly associated with IIV uptake (risk ratio (RR): 8.60, 95% CI 8.48-8.73). This trend was temporally and jurisdictionally consistent. First Nations women were more likely to have had IIV in pregnancy before the introduction of dTpa in the pregnancy program: (RR: 1.48, 95% CI 1.40-1.57), but less likely after dTpa implementation (RR: 0.78, 95% CI 0.76-0.80).

CONCLUSIONS

Inequity in vaccine uptake between First Nations and non-Indigenous pregnancies, and dismal rates of vaccination in pregnancy overall need urgent review, particularly before the next influenza pandemic or pertussis outbreak. If antenatal dTpa is driving IIV uptake, changes in antenatal healthcare practices are needed to ensure vaccines are offered equitably and optimally to protect against infection.

The risk of major structural birth defects associated with seasonal influenza vaccination during pregnancy: A population-based cohort study

INTRODUCTION

Seasonal inactivated influenza vaccine (IIV) is routinely recommended during pregnancy to protect both mothers and infants from complications following influenza infection. While previous studies have evaluated the risk of major structural birth defects in infants associated with prenatal administration of monovalent pandemic IIV, fewer studies have evaluated the risk associated with prenatal seasonal IIV.

METHODS

We conducted a population-based cohort study of 125,866 singleton births between 2012 and 2016 in Western Australia. Birth registrations were linked to the state's registers for congenital anomalies and a state prenatal vaccination database. We estimated prevalence ratios (PR) of any major structural birth defect and defects by organ system. Vaccinated pregnancies were defined as those with a record of IIV in the first trimester. Inverse probability treatment weighting factored for baseline probability for vaccination. A Bonferroni correction was applied to account for multiple comparisons.

RESULTS

About 3.9% of births had a major structural birth defect. Seasonal IIV exposure during the first trimester was not associated with diagnosis of any major structural birth defect diagnosed within 1 month of birth (PR 0.98, 95% CI: 0.77, 1.28) or within 6 years of life (PR 1.02, 95% CI: 0.78, 1.35). We identified no increased risk in specific birth defects associated with seasonal IIV.

CONCLUSION

Based on registry data for up to 6 years of follow-up, results suggest there is no association between maternal influenza vaccination and risk of major structural birth defects. These results support the safety of seasonal IIV administration during pregnancy.

Neuropsychiatric outcomes in offspring after fetal exposure to maternal influenza infection during pregnancy: A systematic review

Increasing evidence suggests that influenza infection in pregnancy may disrupt fetal neurodevelopment. The impact of maternal influenza infection on offspring neuropsychiatric health has not been comprehensively reviewed. We systematically reviewed comparative studies evaluating associations between maternal influenza infection and neuropsychiatric health outcomes in offspring. We searched MEDLINE, EMBASE, CINAHL, and Web of Science for articles published until January 7, 2022. Included were English studies evaluating neuropsychiatric outcomes in offspring aged > 6 months born to women with and without influenza during pregnancy, defined as clinical or laboratory-confirmed influenza illness, or being pregnant during pandemics/epidemics. Of 12,010 records screened, 42 studies were included. Heterogeneity in study design, exposures, and outcome definitions precluded meta-analyses. Four of 14 studies assessing schizophrenia reported adjusted ratio estimates from 0.5 to 8.2; most 95% CIs contained the null value; study quality was high in three of four. Two studies reported an increased risk of schizophrenia with influenza exposure any time during pregnancy (adjusted incidence rate ratio 8.2, 95% CI: 1.4-48.8; adjusted odds ratio 1.3, 95% CI: 1.2-1.5); another reported a reduced risk with first-trimester exposure (adjusted risk ratio 0.5, 95% CI: 0.3-0.9). Seven studies of autism spectrum disorder reported adjusted ratio estimates from 0.9 to 4.0; all 95% CIs included the null value; study quality was high in four. No conclusions could be drawn about the association between exposure to maternal influenza and neuropsychiatric outcomes due to the limited quantity and quality of available research. Large observational studies with long-term follow-up are required to investigate these associations.

Maternal influenza vaccination and child mortality: Longitudinal, population-based linked cohort study

Influenza vaccination is recommended to protect mothers and their infants from influenza. Few studies have evaluated the association between maternal influenza vaccination and child mortality. We aimed to evaluate the association between in utero exposure to seasonal inactivated influenza vaccine (IIV) and mortality among young children. This longitudinal, population-based cohort study included 191,247 maternal-child pairs in Western Australia between April 2012 and December 2017. Maternal vaccine information was obtained from a state-wide antenatal vaccination database. Mortality was defined as a record of a death registration. We used Cox proportional hazard models, weighted by the inverse-probability of treatment (vaccination), to estimate the hazard ratio of child mortality associated with in utero exposure to seasonal IIV. This study found no association between in utero exposure to seasonal IIV and mortality through age five years.

Potentially Pathogenic Organisms in Stools and Their Association With Acute Diarrheal Illness in Children Aged <2 Years

BACKGROUND

Acute diarrheal illness (ADI) causes a substantial disease burden in high-income countries. We investigated associations between potentially pathogenic organisms in stools and ADI by polymerase chain reaction (PCR) in Australian children aged <2 years.

METHODS

Children in a community-based birth cohort had gastrointestinal symptoms recorded daily and stool samples collected weekly until their second birthday. Diarrhea was defined as ≥3 liquid or looser than normal stools within a 24-hour period. PCR assays tested for 11 viruses, 5 bacteria, and 4 protozoa. Detections of a new organism or of the same following at least 2 negative tests were linked to ADIs, and incidence rates and estimates of association with ADI were calculated.

RESULTS

One hundred fifty-four children provided 11 111 stool samples during 240 child-years of observation, and 228 ADIs were linked to samples. Overall, 6105 (55%) samples tested positive for a target organism. The incidence rate of 2967 new detections was 11.9 (95% confidence interval 11.4-12.3) per child-year, with 2561 (92%) new detections unrelated to an ADI. The relative risk of an ADI was 1.5-6.4 times greater for new detections of adenovirus, enterovirus, norovirus GII, parechovirus A, wild-type rotavirus, sapovirus GI/II/IV/V, Salmonella, Blastocystis, and Cryptosporidium, compared to when these were absent.

CONCLUSIONS

Wild-type rotavirus, norovirus GII, sapovirus GI/II/IV/V, adenovirus 40/41, and Salmonella were associated with ADI in this age group and setting. However, high levels of asymptomatic shedding of potential pathogens in stools from children may contribute to diagnostic confusion when children present with an episode of ADI.

Prenatal influenza vaccination and allergic and autoimmune diseases in childhood: A longitudinal, population-based linked cohort study

BACKGROUND

Few studies have evaluated the effect of maternal influenza vaccination on the development of allergic and autoimmune diseases in children beyond 6 months of age. We aimed to investigate the association between in utero exposure to seasonal inactivated influenza vaccine (IIV) and subsequent diagnosis of allergic and autoimmune diseases.

METHODS AND FINDINGS

This longitudinal, population-based linked cohort study included 124,760 singleton, live-born children from 106,206 mothers in Western Australia (WA) born between April 2012 and July 2016, with up to 5 years of follow-up from birth. In our study cohort, 64,169 (51.4%) were male, 6,566 (5.3%) were Aboriginal and/or Torres Strait Islander children, and the mean age at the end of follow-up was 3.0 (standard deviation, 1.3) years. The exposure was receipt of seasonal IIV during pregnancy. The outcomes were diagnosis of an allergic or autoimmune disease, including asthma and anaphylaxis, identified from hospital and/or emergency department (ED) records. Inverse probability of treatment weights (IPTWs) accounted for baseline probability of vaccination by maternal age, Aboriginal and/or Torres Strait Islander status, socioeconomic status, body mass index, parity, medical conditions, pregnancy complications, prenatal smoking, and prenatal care. The models additionally adjusted for the Aboriginal and/or Torres Strait Islander status of the child. There were 14,396 (11.5%) maternally vaccinated children; 913 (6.3%) maternally vaccinated and 7,655 (6.9%) maternally unvaccinated children had a diagnosis of allergic or autoimmune disease, respectively. Overall, maternal influenza vaccination was not associated with diagnosis of an allergic or autoimmune disease (adjusted hazard ratio [aHR], 1.02; 95% confidence interval [CI], 0.95 to 1.09). In trimester-specific analyses, we identified a negative association between third trimester influenza vaccination and the diagnosis of asthma (n = 40; aHR, 0.70; 95% CI, 0.50 to 0.97) and anaphylaxis (n = 36; aHR, 0.67; 95% CI, 0.47 to 0.95).We did not capture outcomes diagnosed in a primary care setting; therefore, our findings are only generalizable to more severe events requiring hospitalization or presentation to the ED. Due to small cell sizes (i.e., <5), estimates could not be determined for all outcomes after stratification.

CONCLUSIONS

In this study, we observed no association between in utero exposure to influenza vaccine and diagnosis of allergic or autoimmune diseases. Although we identified a negative association of asthma and anaphylaxis diagnosis when seasonal IIV was administered later in pregnancy, additional studies are needed to confirm this. Overall, our findings support the safety of seasonal inactivated influenza vaccine during pregnancy in relation to allergic and autoimmune diseases in early childhood and support the continuation of current global maternal vaccine programs and policies.

Association between vaccination status, symptom identification and healthcare use: Implications for test negative design observational studies

AIM

To test the internal validity of the test-negative design (TND) by investigating associations between maternal influenza vaccination, and new virus detection episodes (VDEs), acute respiratory illness, and healthcare visits in their children.

METHODS

Eighty-five children from a birth cohort provided daily symptoms, weekly nasal swabs, and healthcare use data until age 2-years. Effect estimates are summarised as incidence rate ratios (IRR).

RESULTS

There was no association between maternal vaccination and VDEs in children (IRR = 1.1; 95 %CI = 0.9-1.2). Influenza-vaccinated mothers were more likely than unvaccinated mothers to both report, and seek healthcare for, acute lower respiratory illness in their children, IRR = 2.4; 95 %CI = 1.2-4.8 and IRR = 2.2; 95 %CI = 1.1-4.3, respectively.

CONCLUSION

A key assumption of the TND, that healthcare seeking behaviour for conditions of the same severity is not associated with vaccine receipt, did not hold. Further studies of the performance of the TND in different populations are required to confirm its validity.

Longitudinal, population-based cohort study of prenatal influenza vaccination and influenza infection in childhood

BACKGROUND

Influenza vaccination is recommended to protect mothers and their infants from influenza infection. Few studies have evaluated the health impacts of in utero exposure to influenza vaccine among children more than six months of age.

METHODS

We used probabilistically linked administrative health records to establish a mother-child cohort to evaluate the risk of influenza and acute respiratory infections associated with maternal influenza vaccination. Outcomes were laboratory-confirmed influenza (LCI) and hospitalization for influenza or acute respiratory infection (ARI). Adjusted hazard ratios (aHRs) accounted for child's Aboriginal status and were weighted by the inverse-probability of treatment.

RESULTS

14,396 (11.5%) children were born to vaccinated mothers. Maternally vaccinated infants aged < 6 months had lower risk of LCI (aHR: 0.33; 95% CI: 0.13, 0.85), influenza-associated hospitalization (aHR: 0.39; 95% CI: 0.16, 0.94) and ARI-associated hospitalization (aHR: 0.85; 95% CI: 0.77, 0.94) compared to maternally unvaccinated infants. With the exception of an increased risk of LCI among children aged 6 months to < 2 years old following first trimester vaccination (aHR: 2.28; 95% CI: 1.41, 3.69), there were no other differences in the risk of LCI, influenza-associated hospitalization or ARI-associated hospitalization among children aged > 6 months.

CONCLUSION

Study results show that maternal influenza vaccination is effective in preventing influenza in the first six months and had no impact on respiratory infections after two years of age.

Early Childhood Health Outcomes Following In Utero Exposure to Influenza Vaccines: A Systematic Review

CONTEXT

Vaccination during pregnancy is an effective strategy for preventing infant disease; however, little is known about early childhood health after maternal vaccination.

OBJECTIVES

To systematically review the literature on early childhood health associated with exposure to influenza vaccines in utero.

DATA SOURCES

We searched CINAHL Plus, Embase, Medline, Scopus, and Web of Science for relevant articles published from inception to July 24, 2019.

STUDY SELECTION

We included studies published in English reporting original data with measurement of in utero exposure to influenza vaccines and health outcomes among children <5 years of age.

DATA EXTRACTION

Two authors independently assessed eligibility and extracted data on study design, setting, population, vaccines, outcomes, and results.

RESULTS

The search yielded 3647 records, of which 9 studies met the inclusion criteria. Studies examined infectious, atopic, autoimmune, and neurodevelopmental outcomes, and all-cause morbidity and mortality. Authors of 2 studies reported an inverse association between pandemic influenza vaccination and upper respiratory tract infections, gastrointestinal infections, and all-cause hospitalizations; and authors of 2 studies reported modest increased association between several childhood disorders and pandemic or seasonal influenza vaccination, which, after adjusting for confounding and multiple comparisons, were not statistically significant.

LIMITATIONS

Given the small number of studies addressing similarly defined outcomes, meta-analyses were deemed not possible.

CONCLUSIONS

Results from the few studies in which researchers have examined outcomes in children older than 6 months of age did not identify an association between exposure to influenza vaccines in utero and adverse childhood health outcomes.

'Links2HealthierBubs' cohort study: protocol for a record linkage study on the safety, uptake and effectiveness of influenza and pertussis vaccines among pregnant Australian women

INTRODUCTION

Pregnant women and infants are at risk of severe influenza and pertussis infection. Inactivated influenza vaccine (IIV) and diphtheria-tetanus-acellular pertussis vaccine (dTpa) are recommended during pregnancy to protect both mothers and infants. In Australia, uptake is not routinely monitored but coverage appears sub-optimal. Evidence on the safety of combined antenatal IIV and dTpa is fragmented or deficient, and there remain knowledge gaps of population-level vaccine effectiveness. We aim to establish a large, population-based, multi-jurisdictional cohort of mother-infant pairs to measure the uptake, safety and effectiveness of antenatal IIV and dTpa vaccines in three Australian jurisdictions. This is a first step toward assessing the impact of antenatal vaccination programmes in Australia, which can then inform government policy with respect to future strategies in national vaccination programmes. METHODS AND ANALYSIS: 'Links2HealthierBubs' is an observational, population-based, retrospective cohort study established through probabilistic record linkage of administrative health data. The cohort includes births between 2012 and 2017 (~607 605 mother-infant pairs) in jurisdictions with population-level antenatal vaccination and health outcome data (Western Australia, Queensland and the Northern Territory). Perinatal data will be the reference frame to identify the cohort. Jurisdictional vaccination registers will identify antenatal vaccination status and the gestational timing of vaccination. Information on maternal, fetal and child health outcomes will be obtained from hospitalisation and emergency department records, notifiable diseases databases, developmental anomalies databases, birth and mortality registers.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Western Australian Department of Health, Curtin University, the Menzies School of Health Research, the Royal Brisbane and Women's Hospital, and the West Australian Aboriginal Health Ethics Committees. Research findings will be disseminated in peer-reviewed journals, at scientific meetings, and may be incorporated into communication materials for public health agencies and the public.

Timing of First Respiratory Virus Detections in Infants: A Community-Based Birth Cohort Study

Background

Determining timing of first virus detection episodes (fVDEs) for different respiratory viruses in infants identifies risk periods and informs preventive interventions, including vaccination. We describe the ages and nature of fVDEs in an infant birth cohort and explore factors associated with increased odds of symptomatic fVDEs.

Methods

The Observational Research in Childhood Infectious Diseases (ORChID) study is a community-based birth cohort describing acute respiratory infections in infants until their second birthday. Parents recorded daily symptoms and collected nose swabs weekly, which were batch-tested using polymerase chain reaction assays for 17 respiratory viruses.

Results

One hundred fifty-eight infants participated in ORChID. The median age for fVDEs was 2.9 months for human rhinovirus (HRV) but was ≥13.9 months for other respiratory viruses. Overall, 52% of HRV fVDEs were symptomatic, compared with 57%–83% of other fVDEs. Respiratory syncytial virus and human metapneumovirus fVDEs were more severe than HRV fVDEs. Older age and the winter season were associated with symptomatic episodes.

Conclusions

Infants do not always experience respiratory symptoms with their fVDE. Predominance of early HRV detections highlights the need for timing any intervention early in life. fVDEs from other respiratory viruses most commonly occur when maternal vaccines may no longer provide protection.

Nasal swab bacteriology by PCR during the first 24-months of life: A prospective birth cohort study

BACKGROUND

Most respiratory bacterial carriage studies in children are based on cross-sectional samples or longitudinal studies with infrequent sampling points. The prospective Observational Research in Childhood Infectious Diseases birth cohort study intensively evaluated the community-based epidemiology of respiratory viruses and bacteria during the first 2-years of life. Here we report the bacteriologic findings.

METHODS

Pregnant women in Brisbane, Australia were recruited between September 2010 and October 2012, and their healthy newborn children were followed for the first 2-years of life. Parents kept a daily symptom diary for the study child, collected a weekly anterior nose swab and completed an illness burden diary when their child met pre-defined illness criteria. Specimens were tested for respiratory bacteria by real-time polymerase chain reaction (PCR) assays and those containing human genomic DNA, deemed as high-quality, were analyzed.

RESULTS

Altogether 8100 high-quality nasal swab specimens from 158 enrolled children were analyzed. Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae were detected in 42.4%, 38.9%, and 14.8% of these samples, respectively. Concomitant detection of bacteria was common. In contrast, Bordetella pertussis, B. parapertussis, Mycoplasma pneumoniae, Chlamydia pneumoniae, and Simkania negevensis were rarely identified. The prevalence of the three major bacteria was higher with increasing age and in the winter and spring months. Siblings and childcare attendance were the other risk factors identified.

CONCLUSIONS

We confirmed the feasibility of frequent nasal swabbing by parents for studying bacterial colonization. PCR detected the major respiratory tract bacteria with expected high frequencies, but atypical bacteria were found rarely in this cohort.

Viruses causing lower respiratory symptoms in young children: findings from the ORChID birth cohort

INTRODUCTION

Viral acute respiratory infections (ARIs) cause substantial child morbidity. Sensitive molecular-based assays aid virus detection, but the clinical significance of positive tests remains uncertain as some viruses may be found in both acutely ill and healthy children. We describe disease-pathogen associations of respiratory viruses and quantify virus-specific attributable risk of ARIs in healthy children during the first 2 years of life.

METHODS

One hundred fifty-eight term newborn babies in Brisbane, Australia, were recruited progressively into a longitudinal, community-based, birth cohort study conducted between September 2010 and October 2014. A daily tick-box diary captured predefined respiratory symptoms from birth until their second birthday. Weekly parent-collected nasal swabs were batch-tested for 17 respiratory viruses by PCR assays, allowing calculation of virus-specific attributable fractions in the exposed (AFE) to determine the proportion of virus-positive children whose ARI symptoms could be attributed to that particular virus.

RESULTS

Of 8100 nasal swabs analysed, 2646 (32.7%) were virus-positive (275 virus codetections, 3.4%), with human rhinoviruses accounting for 2058/2646 (77.8%) positive swabs. Viruses were detected in 1154/1530 (75.4%) ARI episodes and in 984/4308 (22.8%) swabs from asymptomatic periods. Respiratory syncytial virus (AFE: 68% (95% CI 45% to 82%)) and human metapneumovirus (AFE: 69% (95% CI 43% to 83%)) were strongly associated with higher risk of lower respiratory symptoms.

DISCUSSION

The strong association of respiratory syncytial virus and human metapneumovirus with ARIs and lower respiratory symptoms in young children managed within the community indicates successful development of vaccines against these two viruses should provide substantial health benefits.

The burden of community-managed acute respiratory infections in the first 2-years of life

BACKGROUND

Contemporary information on acute respiratory infections (ARIs) in children is based on hospital cohorts, primary healthcare presentations, and high-risk birth cohort studies. We describe the burden and determinants of symptomatic episodes of ARIs in unselected healthy infants in the first 2-years of life.

METHODS

One hundred and fifty-four infants from subtropical Brisbane, Australia participated in a longitudinal, community-based birth cohort study. A daily tick-box diary captured pre-defined respiratory symptoms. Parents also completed a burden diary, recording family physician and hospital visits, and antibiotic use.

RESULTS

Participants contributed 88,032 child-days (78.2% of expected), of which 17,316 (19.7%) days were symptomatic during 1,651 ARI episodes: incidence rate 0.56 ARIs per child-month (95%CI: 0.54, 0.59). Runny nose (14,220 days; 6.0-days median duration) and dry cough (6,880 days; 4.0-days median duration) were reported most frequently. Overall, 955 burden diaries recorded 455 family physician visits (1-8 visits per ARI) and 48 hospital presentations, including six hospital admissions. Antibiotics were prescribed on 209 occasions (21.9% of ARI episodes where burden diary submitted). Increasing age, non-summer seasons, and attendance at childcare were associated with an increased risk of ARI.

CONCLUSIONS

ARIs are a common cause of morbidity in the first 2-years of life, with children experiencing 13 discrete ARI episodes and almost 5-months of respiratory symptoms. Most ARIs are managed in the community by parents and family physicians. Antibiotic prescribing remains common for ARIs in young children. Secular societal changes, including greater use of childcare in early childhood, may have maintained the high ARI incidence in this age-group. Pediatr Pulmonol. 2016;51:1336-1346. © 2016 Wiley Periodicals, Inc.

A systematic review of community-based interventions for emerging zoonotic infectious diseases in Southeast Asia

Background

Southeast Asia has been at the epicentre of recent epidemics of emerging and re-emerging zoonotic diseases. Community-based surveillance and control interventions have been heavily promoted but the most effective interventions have not been identified.

Objectives

This review evaluated evidence for the effectiveness of community-based surveillance interventions at monitoring and identifying emerging infectious disease; the effectiveness of community-based control interventions at reducing rates of emerging infectious disease; and contextual factors that influence intervention effectiveness.

Inclusion criteria

Participants

Communities in Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Viet Nam.

Types of intervention(s)

Non-pharmaceutical, non-vaccine, and community-based surveillance or prevention and control interventions targeting rabies, Nipah virus, dengue, SARS or avian influenza.

Types of outcomes

Primary outcomes: measures: of infection or disease; secondary outcomes: measures of intervention function.

Types of studies

Original quantitative studies published in English.

Search strategy

Databases searched (1980 to 2011): PubMed, CINAHL, ProQuest, EBSCOhost, Web of Science, Science Direct, Cochrane database of systematic reviews, WHOLIS, British Development Library, LILACS, World Bank (East Asia), Asian Development Bank.

Methodological quality

Two independent reviewers critically appraised studies using standard Joanna Briggs Institute instruments. Disagreements were resolved through discussion.

Data extraction

A customised tool was used to extract quantitative data on intervention(s), populations, study methods, and primary and secondary outcomes; and qualitative contextual information or narrative evidence about interventions.

Data synthesis

Data was synthesised in a narrative summary with the aid of tables. Meta-analysis was used to statistically pool quantitative results.

Results

Fifty-seven studies were included. Vector control interventions using copepods, environmental cleanup and education are effective and sustainable at reducing dengue in rural and urban communities, whilst insecticide spraying is effective in urban outbreak situations. Community-based surveillance interventions can effectively identify avian influenza in backyard flocks, but have not been broadly applied. Outbreak control interventions for Nipah virus and SARS are effective but may not be suitable for ongoing control. Canine vaccination and education is more acceptable than culling, but still fails to reach coverage levels required to effectively control rabies. Contextual factors were identified that influence community engagement with, and ultimately effectiveness of, interventions.

Conclusion

Despite investment in community-based disease control and surveillance in Southeast Asia, published evidence evaluating interventions is limited in quantity and quality. Nonetheless this review identified a number of effective interventions, and several contextual factors influencing effectiveness. Identification of the best programs will require comparative evidence of effectiveness acceptability, cost-effectiveness and sustainability.

Implications for practice

Interventions are more effective if there are high levels of community ownership and engagement. Linkages between veterinary and public health surveillance systems are essential. Interventions are not well accepted when they fail to acknowledge the importance of animals for economic activity in communities.

Implications for research

Evidence is needed on functioning and outcomes of current surveillance systems and novel low-cost methods of surveillance. Evaluations of control interventions should control for confounding and report measures of disease, cost and sustainability. Translational research is needed to assess generalisability and evaluate roll-out of effective interventions as regional or national programs.

Fasting glucose and cardiovascular risk factors in an urban population

OBJECTIVE

To test the hypothesis that blood glucose levels in the range of normoglycemia are associated with increased cardiovascular risk we performed an epidemiological study in an urban population.

METHODS

Randomly selected adults > or = 20 years were studied using stratified sampling. Target sample was 1800 (men 960, women 840) of which 1123 subjects participated. Blood samples were available in 1091 subjects (60.6%, men 532, women 559). Measurement of anthropometric variables, blood pressure, fasting blood glucose and lipids was performed. Cardiovascular risk factors were determined using US Adult Treatment Panel-3 guidelines. Pearson's correlation coefficients (r) of fasting glucose with various risk factors were determined. Fasting glucose levels were classified into various groups as < 75 mg/dl, 75-89 mg/dl, 90-109 mg/dl, 110-125 mg/dl and > 126 mg/dl or known diabetes. Prevalence of cardiovascular risk factors was determined in each group.

RESULTS

There was a significant positive correlation of fasting glucose in men and women with body mass index (r = 0.20, 0.12), waist-hip ratio (0.17, 0.09), systolic blood pressure (0.07, 0.22), total cholesterol (0.21, 0.15) and triglycerides (0.21, 0.25). Prevalence (%) of cardiovascular risk factors in men and women was smoking/tobacco use in 37.6 and 11.6, hypertension in 37.0 and 37.6, overweight and obesity in 37.8 and 50.3, truncal obesity in 57.3 and 68.0, high cholesterol > or = 200 mg/dl in 37.4 and 45.8, high triglycerides > or = 150 mg/dl in 32.3 and 28.6 and metabolic syndrome in 22.9 and 31.6 percent. In various groups of fasting glucose there was an increasing trend in prevalence of overweight/obesity, hypertension, hypercholesterolaemia, hypertriglyceridaemia, and metabolic syndrome (Mantel-Haenzel X2 for trend, p < 0.05) and fasting glucose < 75 mg/dl was associated with the lowest prevalence of these risk factors.

CONCLUSIONS

There is a continuous relationship of fasting glucose levels with many cardiovascular risk factors and level < 75 mg/dl is associated with the lowest prevalence.

Body-mass index, waist-size, waist-hip ratio and cardiovascular risk factors in urban subejcts

BACKGROUND AND OBJECTIVE

Influence of obesity as determinant of cardiovascular risk factors has not been well studied. To determine association of obesity, measured by body-mass index (BMI), waist-size or waist-hip ratio (WHR), with multiple risk factors in an urban Indian population we performed an epidemiological study.

METHODS

Randomly selected adults > or = 20 years were studied using stratified sampling. Target sample was 1800 (men 960, women 840). 1123 subjects (response 62.4%) were evaluated and blood samples were available in 532 men and 559 women (n=1091, response 60.6%). Measurement of anthropometric variables, blood pressure, fasting blood glucose and lipids was performed. Atherosclerosis risk factors were determined using current guidelines. Pearson's correlation coefficients (r) of BMI, waist and WHR with various risk factors were determined. BMI was categorized into five groups: <20.0 Kg/m2, 20.0-22.9, 23.0-24.9, 25.0-29.9, and > or = 30 Kg/m2; waist size was divided into five groups and WHR into six groups in both men and women. Prevalence of cardiovascular risk factors, smoking, hypertension, diabetes, metabolic syndrome and dyslipidaemias was determined in each group and trends analyzed using least-squares regression.

RESULTS

There is a significant positive correlation of BMI, waist-size and WHR with systolic BP (r= 0.46 to 0.13), diastolic BP (0.42 to 0.16), fasting glucose (0.15 to 0.26), and LDL cholesterol (0.16 to 0.03) and negative correlation with physical activity and HDL cholesterol (-0.22 to -0.08) in both men and women (p<0.01). With increasing BMI, waist-size and WHR, prevalence of hypertension, diabetes, and metabolic syndrome increased significantly (p for trend <0.05). WHR increase also correlated significantly with prevalence of high total and LDL cholesterol and triglycerides (p <0.05).

CONCLUSIONS

There is a continuous positive relationship of all markers of obesity (body-mass index, waist size and waist hip ratio) with major coronary risk factors- hypertension, diabetes and metabolic syndrome while WHR also correlates with lipid abnormalities.

Internationally Distributed Frozen Oyster Meat Causing Multiple Outbreaks of Norovirus Infection in Australia

BACKGROUND

Between November 2003 and January 2004, outbreaks of norovirus in 3 Australian jurisdictions involving 83 cases of illness were associated with imported oyster meat.

METHODS

Cohort studies were conducted in 2 jurisdictions to identify relative risks of illness for the consumption of oysters. A case series was conducted in the third jurisdiction.

RESULTS

The cohort studies conducted in the first 2 jurisdictions identified relative risks of illness of 17 (95% confidence interval, 5-51) and 35 (95% confidence interval, 5-243), respectively, for the consumption of oysters. Multiple strains of norovirus were detected in fecal specimens from 8 of 14 patients and in 1 of the 3 batches of implicated oyster meat using seminested reverse-transcriptase polymerase chain reaction methods. Traceback investigations revealed that all oyster meat was harvested from the same estuary system in Japan within the same month.

CONCLUSIONS

These outbreaks demonstrate the potential of foodborne disease to spread internationally and the need for national and international collaboration to investigate such outbreaks. Foodborne illness related to norovirus is underestimated because of underreporting of human cases and challenges in laboratory detection of viruses in foods, both of which can delay public health action.

Serial epidemiological surveys in an urban Indian population demonstrate increasing coronary risk factors among the lower socioeconomic strata

OBJECTIVE

To determine trends of coronary risk factors in an Indian urban population and their association with educational level as marker of socioeconomic status.

METHODS

Two successive coronary risk factor surveys were performed in randomly selected individuals. In the first study (in 1995) 2212 subjects (1415 men, 797 women) and in the second (in 2002) 1123 subjects (550 men, 573 women) were studied. Details of smoking, physical activity, hypertension, diabetes, coronary heart disease, body-mass index, waist-hip ratio, blood pressure and electrocardiography were evaluated. Fasting blood was examined for lipid levels in 297 (199 men, 98 women) in the first and in 1082 (532 men, 550 women) in the second study. Educational status was classified into Group 0: no formal education, Group I: 1-10 years, Group II: 11-15 years, and Group III: > 16 years. Current definitions were used for risk factors in both the studies.

RESULTS

Prevalence of coronary risk factors, adjusted for age and educational status, in the first and second study in men was smoking/tobacco in 38.7 vs. 40.5%, leisure time physical inactivity in 70.8 vs. 66.1%, hypertension (> or = 140 and/or 90 mm Hg) in 29.5 vs. 33.7%, diabetes history in 1.1 vs. 7.8%, obesity (body-mass index > or = 25 Kg/m2) in 20.7 vs. 33.0%, and truncal obesity (waist:hip > 0.9) in 54.7 vs. 54.4%. In women, tobacco use was in 18.7 vs. 20.5%, leisure time physical inactivity in 72.4 vs. 75.3%, hypertension in 36.9 vs. 33.7%, diabetes history in 1.0 vs. 7.3%, obesity in 19.9 vs. 39.4%, and truncal obesity (waist:hip > 0.8) in 70.1 vs. 69.2%. In men, high total cholesterol > or = 200 mg/dl was in 24.6 vs. 37.4%, high LDL cholesterol > or = 130 mg/dl in 22.1 vs. 37.0%, high triglycerides > or = 150 mg/dl in 26.6 vs. 30.6% and low HDL cholesterol < 40 mg/dl in 43.2 vs. 54.9%; while in women these were in 22.5 vs. 43.1%, 28.6 vs. 45.1%, 28.6 vs. 28.7% and 45.9 vs. 54.2% respectively. In the second study there was a significant increase in diabetes, obesity, hypertension (men), total- and LDL cholesterol and triglycerides and decrease in HDL cholesterol (p < 0.05). In the first study with increasing educational status a significant increase of obesity, total cholesterol, LDL cholesterol and triglycerides and decrease in smoking was observed. In the second study increasing education was associated with decrease in smoking, leisure-time physical inactivity, total and LDL cholesterol, and triglycerides and increase in obesity, truncal obesity and hypertension (Least-squares regression p < 0.05). Increase in smoking, diabetes and dyslipidaemias was greater in the less educated groups.

CONCLUSIONS

Significant increase in coronary risk factors--obesity, diabetes, total-, LDL-, and low HDL cholesterol, and triglycerides is seen in this urban Indian population over a seven year period. Smoking, diabetes and dyslipidaemias increased more in low educational status groups.

An outbreak of Salmonella typhimurium PTI35 gastroenteritis associated with a minimally cooked dessert containing raw eggs

In April 2000, we investigated an outbreak of gastroenteritis amongst attendees of a local community dinner in a Perth suburb. Of the 98 people interviewed (response rate 98%), 53 reported gastrointestinal symptoms (attack rate 54%). Faecal cultures from 11 cases, 2 food preparers, 1 waitress and leftover mock ice-cream dessert grew Salmonella Typhimurium PT135. Of the 3 food handlers, one was asymptomatic, another gave an unclear history of onset of illness and the waitress claimed illness onset 9 days after the dinner. A cohort study implicated fruit salad (RR 1.64 [95% CI: 1.05-2.58], p=0.017) and/or mock ice-cream dessert (RR 1.78 [95% CI: 0.91-3.52], p=0.045). Eggs used to make the mock ice-cream dessert were supplied directly from the producer who used inappropriate shell cleaning methods. The method of preparation of the dessert encouraged contamination. Salmonella species were not isolated in poultry faecal samples collected from the implicated egg farm. The cause of this outbreak was almost certainly the ice-cream dessert with contamination most likely resulting either from the eggs used to make the dessert or one or both of the food preparers, coupled with inadequate cooking of the dessert. Eggs used in preparing food for mass consumption should be sourced from distributors with approved cleaning procedures. Furthermore, pasteurised egg products or egg pulp should be used in the preparation of uncooked or minimally cooked dishes.

Lipid abnormalities in coronary heart disease: a population-based case-control study

BACKGROUND

We performed a case-control study to estimate lipid-cholesterol fractions in patients with coronary heart disease and compared them with population-based controls.

METHODS AND RESULTS

A total of 635 newly diagnosed patients with coronary heart disease (518 males and 117 females) and 632 subjects (346 males and 286 females) obtained from an ongoing urban coronary heart disease risk factor epidemiological study were evaluated. Age-specific lipid values (total cholesterol, low-density lipoprotein, high-density lipoprotein, triglycerides, and total:high-density lipoprotein cholesterol ratio) were compared using the t-test. Age-adjusted prevalence of dyslipidemia as defined by the US National Cholesterol Education Program was compared using the Chi-square test. In all the age groups, and in both males and females, levels of total and low-density lipoprotein cholesterol were not significantly different. In males, the high-density lipoprotein cholesterol (mg/dl) was significantly lower in patients with coronary heart disease as compared to controls in the age groups 30-39 years (35.1+/-11 v. 43.7+/-9), 40-49 years (39.0+/-10 v. 47.1+/-8), 50-59 years (38.9+/-11 v. 43.8+/-9) and 60-69 years (38.6+/-11, v. 42.8+/-7) (p<0.05). In females, high-density lipoprotein cholesterol was less in the age groups 30-39 years (30.2+/-9 v. 40.7+/-9), 50-59 years (39.7+/-12 v. 44.7+/-8) and 60-69 years (35.6+/-11 v. 42.2+/-9). The level of triglycerides was significantly higher in male patients in the age groups 40-49 years (195.3+/-96 v. 152.8+/-78), 50-59 years (176.7+/-76 v. 162.9+/-97), 60-69 years (175.5+/-93 v. 148.1+/-65) and >70 years (159.8+/-62 v. 100.0+/-22); and in female patients in the age group 30-39 years (170.8+/-20 v. 149.9+/-9) (p<0.05). The total:high-density lipoprotein cholesterol ratio was significantly higher in all age groups in male as well as female patients with coronary heart disease (p<0.05).

CONCLUSIONS

An age-adjusted case-control comparison showed that the prevalence of hypertension, diabetes, high total cholesterol (> or =200 mg/dl) (males 48.8% v. 20.2%; females 59.8% v. 33.4%) and high low-density lipoprotein cholesterol (> or =130 mg/dl) (males 42.1% v. 15.0%; females 52.1% v. 31.0%) was significantly more in cases than in controls. The prevalence of low high-density lipoprotein cholesterol (<35 mg/dl) (males 39.6% v. 6.2%; females 39.3% iv 9.5%), high total:high-density lipoprotein ratio (> or = 5.0) and high triglycerides (> or =200 mg/ dl: males 39.6%, v. 10.2%; females 17.1% v. 11.9%) was also significantly higher in cases (p<0.05).

A novel ADP-ribosylation like factor (ARL-6), interacts with the protein-conducting channel SEC61beta subunit

We report here the isolation of a new member of the ADP-ribosylation factor (ARF)-like family (ARL-6) present in the J2E erythroleukemic cell line, but not its myeloid variants. Consistent with this lineage-restricted expression, ARL-6 mRNA increased with erythropoietin-induced maturation of J2E cells, and decreased with interleukin 6-induced differentiation of M1 monoblastoid cells. In tissues, ARL-6 mRNA was most abundant in brain and kidney. While ARL-6 protein was predominantly cytosolic, its membrane association increased following exposure to GTP-gammaS, like many members of the ARF/ARL family. Using the yeast two-hybrid system, six molecules which interact with ARL-6 were identified including SEC61beta, a subunit of the heterotrimeric protein conducting channel SEC61p. Co-immunoprecipitation of ARL-6 confirmed a stable association between ARL-6 and SEC61beta in COS cells. These results demonstrate that ARL-6, a novel member of the ADP-ribosylation factor-like family, interacts with the SEC61beta subunit.

Evaluation of the expression levels of nm23-H1 mRNA in primary breast cancer, benign breast disease, axillary lymph nodes and normal breast tissue

Expression levels of nm23-H1 were evaluated in a variety of normal benign and malignant breast tissues by Northern and slot blot. Tissues from 153 patients presenting with palpable breast lesions were studied: 132 primary infiltrating breast cancers, 9 pure duct carcinoma in situ lesions, a phyllodes tumor, 9 benign lesions and 2 local recurrences of carcinoma. In addition to lesional tissue, 49 samples of macroscopically normal breast tissue, 37 axillary lymph nodes and 9 samples from patients undergoing cosmetic reduction mammoplasty were studied. Sets of normal breast tissue, primary tumor and lymph node tissue from individual patients were available for comparison in 37 cases. A wide range of gene expression was detected in the various tissue types. The highest levels of expression were detected in malignant samples with in situ carcinomas being associated with the highest levels of gene expression. The expression levels of nm23-H1 in normal breast tissue were lower than the corresponding tumors from the same patients (p < 0.0005). Benign breast lesions (including 6 fibroadenomas) had levels of gene expression approximating those of the normal tissue samples. Normal axillary lymph nodes had significantly lower levels of nm23-H1 expression than nodes with metastatic deposits (p < 0.03). No significant association was observed between nm23-H1 expression levels and axillary node status in patients with infiltrating carcinoma, although there was a slight trend toward lower nm23-H1 mRNA levels in the node negative group.(ABSTRACT TRUNCATED AT 250 WORDS)

What's new in breast cancer? Molecular perspectives of cancer development and the role of the oncogene c-erbB-2 in prognosis and disease

The oncogene c-erbB-2 is frequently amplified in human breast carcinoma. The c-erbB-2 gene is present as a single copy in normal cells, and has been mapped to chromosome 17 in the region 17q 12-21.32. c-erbB-2 encodes a transmembrane glycoprotein known as p185. The intracellular component of p185 has tyrosine kinase activity; the extracellular domain has a structure resembling a growth factor receptor. c-erbB-2 amplification, p185 overexpression and levels of transcribed c-erbB-2 specific messenger RNA have been studied in a large number of breast carcinomas using a variety of techniques. In general, overexpression of p185 oncoprotein reflects various levels of DNA amplification, though in some cases amplification can be detected in the absence of overexpression of p185 and similarly overexpression of p185 can be present without detectable levels of c-erbB-2 amplification. This findings suggests that multiple mechanisms may be responsible for overexpression. c-erbB-2 amplification and/or overexpression occurs in almost all cases of high grade duct carcinoma in-situ, but has been reported in only 10%-40% of infiltrating duct carcinoma. c-erbB-2 amplification or overexpression occurs rarely in invasive lobular carcinoma, and has not been detected in ductal or lobular epithelial hyperplasia, or in atypical ductal or atypical lobular hyperplasia. It is generally believed that c-erbB-2 amplification/overexpression is an important independent prognostic indicator in breast carcinoma, identifying a subset of patients with poor prognosis tumours, particularly if axillary node metasases are present. However, many unanswered questions remain regarding c-erbB-2 and its role in breast cancer development and progression. The causes of c-erbB-2 amplification are unknown. There is no evidence of mutations in the human gene which might cause amplification or overexpression. The significance of the differences in levels of c-erbB-2 amplification/overexpression in in-situ duct carcinoma and associated invasive duct carcinoma has not been established. Amplification or overexpression have not been reported in atypical duct hyperplasia, a proposed precursor of duct carcinoma in-situ, yet overexpression occurs almost always in high grade duct carcinoma in-situ. c-erbB-2 may play a critical role in the development of a clonal in-situ, proliferation of high histological grade, yet does not obviously influence the acquisition of an invasive phenotype. We would postulated that this instability in amplification/overexpression is of biological significance, and if better understood may aid in the study of progression of human breast carcinoma.

c-erbB-2 amplification and overexpression in breast cancer: evaluation and comparison of Southern blot, slot blot, ELISA and immunohistochemistry

The oncogene c-erbB-2 has been shown to be amplified in 17-30% of breast cancers, with similar levels of overexpression of the oncogene product p185, a transmembrane growth factor receptor glycoprotein. Amplification of c-erbB-2 is now generally considered to be a significant prognostic indicator in patients with breast cancer. A series of 74 consecutive breast carcinomas were analysed for c-erbB-2 amplification and p185 overexpression. The procedures of Southern blotting and slot blot were used for the analysis of oncogene amplification, while immunoperoxidase (IPOX) staining and enzyme-linked immunosorbent assay (ELISA) were used for the analysis of p185 overexpression. Detection of c-erbB-2 oncogene amplification by both the conventional Southern blotting technique and by the slot blot technique showed complete accord, with the amplified c-erbB-2 oncogene being detected in 14 of the 74 patients (18.9%). The c-erbB-2 oncoprotein, as measured by IPOX and ELISA, was found to be overexpressed in 21% and 19% of patients, respectively. Comparison was made between the results attained by all four methods, and further comparison of the techniques was made from the point of view of ease of use, expense and ease of introduction into routine diagnostic laboratories. Immunocytochemistry in combination with slot blotting procedures were considered to be the most cost effective methods for evaluation of overexpression and amplification in routine pathology laboratories.

Unsupervised waveform classification for multi-neuron recordings: a real-time, software-based system. I. Algorithms and implementation

We describe a new, mostly software-based device for the sorting of waveforms in an extracellular multi-neuron recording situation. The sorting algorithm is largely unattended, and, after an initial 'learning' process, works in real time. Shape comparisons are based on up to 8 time points in the waveform; these points (the reduced feature set) are chosen automatically by analyzing the current incoming data stream. A feasibility version has been implemented on a LSI-11/2 system, using FORTRAN for set-up calculations and assembler for the real-time operations. Detailed comparisons with performance of other sorting devices are presented in the companion paper.