The experience of traumatic events, psychological distress, and social support: links to COVID-19 vaccine hesitancy and trends with age in a group of older Australians

BACKGROUND

Vaccination is important to reduce disease-associated morbidity and mortality in an ageing global population. While older adults are more likely than younger adults to accept vaccines, some remain hesitant. We sought to understand how traumatic events, psychological distress and social support contribute to older adults' intention to receive a COVID-19 vaccine and whether these experiences change with age.

METHODS

We analysed survey data collected as part of the Sax Institute's 45 and Up Study in a population of Australian adults aged 60 years and over. Data were derived from the COVID Insights study; a series of supplementary surveys about how participants experienced the COVID-19 pandemic.

RESULTS

Higher intention to receive a COVID-19 vaccine was associated with greater social support (adjusted odds ratio (aOR):1.08; 95%CI:1.06-1.11; p <.001) while lower intention was associated with personally experiencing a serious illness, injury or assault in the last 12 months (aOR:0.79; 95% CI:0.64-0.98; p =.03). Social support and the experience of traumatic events increased significantly with age, while psychological distress decreased.

CONCLUSIONS

There may be factors beyond disease-associated risks that play a role in vaccine acceptance with age. Older Australians on the younger end of the age spectrum may have specific needs to address their hesitancy that may be overlooked.

Communication Interventions and Assessment of Drivers for Hendra Virus Vaccination Uptake

Hendra virus disease (HeVD) is an emerging zoonosis in Australia, resulting from the transmission of Hendra virus (HeV) to horses from Pteropus bats. Vaccine uptake for horses is low despite the high case fatality rate of HeVD in both horses and people. We reviewed evidence-based communication interventions to promote and improve HeV vaccine uptake for horses by horse owners and conducted a preliminary evaluation of potential drivers for HeV vaccine uptake using the Behavioural and Social Drivers of Vaccination (BeSD) framework developed by the World Health Organization. Six records were eligible for review following a comprehensive search and review strategy of peer-reviewed literature, but evidence-based communication interventions to promote and improve HeV vaccine uptake for horses were lacking. An evaluation of potential drivers for HeV vaccine uptake using the BeSD framework indicated that horse owners' perceptions, beliefs, social processes, and practical issues are similar to those experienced by parents making decisions about childhood vaccines, although the overall motivation to vaccinate is lower amongst horse owners. Some aspects of HeV vaccine uptake are not accounted for in the BeSD framework (for example, alternative mitigation strategies such as covered feeding stations or the zoonotic risk of HeV). Overall, problems associated with HeV vaccine uptake appear well-documented. We, therefore, propose to move from a problems-focused to a solutions-focused approach to reduce the risk of HeV for humans and horses. Following our findings, we suggest that the BeSD framework could be modified and used to develop and evaluate communication interventions to promote and improve HeV vaccine uptake by horse owners, which could have a global application to promote vaccine uptake for other zoonotic diseases in animals, such as rabies.

Association between traumatic life events and vaccine hesitancy: A cross-sectional Australian study

OBJECTIVES

We sought to identify associations between the experience of traumatic life events and vaccination intention to inform whether trauma-affected individuals require targeted interventions when addressing vaccine hesitancy.

STUDY DESIGN

We conducted an online cross-sectional survey to identify whether direct or indirect exposure to various traumatic life events and the presence of post-traumatic stress disorder (PTSD) symptoms are associated with willingness to receive a COVID-19 vaccine in an Australian sample.

METHODS

A national online questionnaire was administered to a representative sample of 1050 Australian adults in September 2021.

RESULTS

Lower willingness to receive a COVID-19 vaccine was associated with direct experience of a fire or explosion (adjusted odds ratio [aOR]: 0.42; 95% confidence interval [CI]: 0.23-0.78; P = 0.006), direct experience of severe human suffering (aOR:0.39; 95% CI: 0.21-0.71; P = 0.002) and screening positive for PTSD symptoms (aOR:0.52; 95% CI: 0.33-0.82; P = 0.005). Conversely, higher willingness to receive a COVID-19 vaccine was associated with indirect exposure to severe human suffering (aOR: 2.0; 95% CI: 1.21-3.22; P = 0.007).

CONCLUSIONS

Our findings suggest that the experience of traumatic events and the presence of PTSD symptoms can contribute to vaccination decisions. Our work adds to the growing recognition of the need to effectively mediate the influence of traumatic experiences on encounters within the medical setting and supports the importance of addressing the needs of trauma-affected individuals in their vaccination experiences.

Willingness to receive a vaccine is influenced by adverse events following immunisation experienced by others

An adverse event following immunization (AEFI) can have consequences for an individual's future decision making and may contribute to vaccine hesitancy. AEFIs vary in severity and can be experienced directly (by an individual themselves) or indirectly (through witnessed or recounted events). We sought to measure the prevalence of specific AEFIs and understand which AEFIs have the greatest associations with reduced willingness to receive a vaccine and how injection anxiety may moderate the relationship. We conducted a cross-sectional online survey with both qualitative and quantitative elements in a sample of adults aged 18 years and over in Australia. Nineteen percent of the 1050 respondents reported experiencing an AEFI that they found stressful. Those who experienced an AEFI reported significantly higher levels of injection anxiety than those who did not. Within the group who reported experiencing an AEFI, respondents were significantly less likely to be willing to receive a COVID-19 vaccine if they reported: indirect exposure to an uncommon/rare AEFI compared with other AEFIs (aOR:0.39; 95% CI: 0.18-0.87); indirect exposure to a scientifically unsupported AEFI compared with other AEFIs (aOR:0.18; 95% CI: 0.05-0.57). Direct exposure to an AEFI was not associated with willingness to receive a COVID-19 vaccine. For those who reported experiencing an AEFI, the odds of willingness to receive a COVID-19 vaccine decreased significantly with an increase in injection anxiety (aOR:0.94; 95% CI: 0.9-0.98). Our results suggest that more is needed to mitigate the consequences of AEFIs on vaccine willingness. Empathically acknowledging at a community level, the experience of both real and perceived AEFIs and incorporating accounts of positive vaccination experiences in vaccine hesitancy interventions may be useful.

Traumatic Events and Vaccination Decisions: A Systematic Review

Despite the apparent relationship between past experiences and subsequent vaccination decisions, the role of traumatic events has been overlooked when understanding vaccination intention and behaviour. We conducted a systematic review to synthesize what is known about the relationship between traumatic events and subsequent vaccination decisions. MEDLINE, PsycINFO and CINHAL electronic databases were searched, and 1551 articles were screened for eligibility. Of the 52 articles included in full-text assessment, five met the eligibility criteria. Findings suggest that the experience of trauma is associated with individual vaccination decisions. Social and practical factors related to both trauma and vaccination may mediate this relationship. As this is a relatively new field of inquiry, future research may help to clarify the nuances of the relationship. This review finds that the experience of psychological trauma is associated with vaccination intention and behaviour and points to the potential importance of a trauma-informed approach to vaccination interventions during the current global effort to achieve high COVID-19 vaccine coverage.

COVID-19 testing decisions and behaviours in two Australian cities

Issue addressed

High levels of testing are crucial for minimising the spread of COVID‐19. The aim of this study is to investigate what prevents people from getting a COVID‐19 test when they are experiencing respiratory symptoms.

Methods

Semi‐structured, qualitative interviews were conducted with 14 purposively sampled adults between 20 November 2020 and 3 March 2021 in two capital cities of Australia and analysed thematically. The analysis included people who reported having respiratory symptoms but who did not undergo a COVID‐19 test.

Results

Participants appraised risks of having COVID‐19, of infecting others or being infected whilst attending a testing site. They often weighed these appraisals against practical considerations of knowing where and how to get tested, inconvenience or financial loss.

Conclusions

Clear public health messages communicating the importance of testing, even when symptoms are minor, may improve testing rates. Increasing the accessibility of testing centres, such as having them at transport hubs is important, as is providing adequate information about testing locations and queue lengths.

So what?

The findings of our study suggest that more needs to be done to encourage people to get tested for COVID‐19, especially when symptoms are minor. Clear communication about the importance of testing, along with easily accessible testing clinics, and financial support for those concerned about financial impacts may improve testing rates.

Stigmatized for standing up for my child: A qualitative study of non-vaccinating parents in Australia

BACKGROUND

Vaccine refusal is highly polarizing in Australia, producing a challenging social landscape for non-vaccinating parents. We sought to understand the lived experience of non-vaccinating parents in contemporary Australia.

METHODS

We recruited a national sample of non-vaccinating parents of children <18 yrs, advertising on national radio, in playgrounds in low vaccination areas, and using snowballing. Grounded Theory methodology guided data collection (via semi-structured interviews). Inductive analysis identified stigmatization as a central concept; stigma theory was adopted as an analytical lens.

RESULTS

Twenty-one parents from regional and urban locations in five states were interviewed. Parent's described experiences point to systematic stigmatization which can be characterized using Link & Phelan's five-step process. Parents experienced (1) labelling and (2) stereotyping, with many not identifying with the "anti-vaxxers" portrayed in the media and describing frustration at being labelled as such, believing they were defending their child from harm. Participants described (3) social "othering", leading to relationship loss and social isolation, and (4) status loss and discrimination, feeling "brushed off" as incompetent parents and discriminated against by medical professionals and other parents. Finally, (5) legislative changes exerted power over their circumstances, rendering them unable to provide their children with the same financial and educational opportunities as vaccinated children, often increasing their steadfastness in refusing vaccination.

CONCLUSION

Non-vaccinating Australian parents feel stigmatized for defending their child from perceived risk of harm, reporting a range of social and psychological effects, as well as financial effects from policies which disadvantaged their children through differential financial treatment, and diminished early childhood educational opportunities. While it might be argued that social stigma and exclusionary policies directed a small minority for the greater good are justified, other more nuanced approaches based on better understandings of vaccine rejection could achieve comparable public health outcomes without the detrimental effect on unvaccinated families.

A user-centered approach to developing a new tool measuring the behavioural and social drivers of vaccination

BACKGROUND

Children around the world remain under-vaccinated for many reasons. To develop effective vaccine delivery programmes and monitor intervention impact, vaccine programme implementers need to understand reasons for under-vaccination within their local context. The World Health Organization (WHO) Working Group on the Behavioural and Social Drivers of Vaccination (BeSD) is developing standardised tools for assessing childhood vaccine acceptance and uptake that can be used across regions and countries. The tools will include: (1) a validated survey; (2) qualitative interview guides; and (3) corresponding user guidance. We report a user-centred needs assessment of key end-users of the BeSD tools.

METHODS

Twenty qualitative interviews (Apr-Aug 2019) with purposively sampled vaccine programme managers, partners and stakeholders from UNICEF and WHO country and regional offices. The interviews assessed current systems, practices and challenges in data utilisation and reflections on how the BeSD tools might be optimised. Framework analysis was used to code the interviews.

RESULTS

Regarding current practices, participants described a variety of settings, data systems, and frequencies of vaccination attitude measurement. They reported that the majority of data used is quantitative, and there is appetite for increased use of qualitative data. Capacity for conducting studies on social/behavioural drivers of vaccination was high in some jurisdictions and needed in others. Issues include barriers to collecting such data and variability in sources. Reflecting on the tools, participants described the need to explore the attitudes and practices of healthcare workers in addition to parents and caregivers. Participants were supportive of the proposed mixed-methods structure of the tools and training in their usage, and highlighted the need for balance between tool standardisation and flexibility to adapt locally.

CONCLUSIONS

A user-centred approach in developing the BeSD tools has given valuable direction to their design, bringing the use of behavioural and social data to the heart of programme planning.

Hand Hygiene Compliance and Effectiveness Against Respiratory Infections Among Hajj Pilgrims: A Systematic Review

The role of hand hygiene in the prevention of respiratory tract infections in Hajj pilgrims has not been assessed through a focussed systematic review of the literature. Considering this, a systematic review was undertaken to synthesize the up-to-date literature on the compliance and effectiveness of hand hygiene among Hajj attendees. Major databases, including OVID Medline, were searched by using a combination of MeSH terms and text words for potentially relevant articles. Data from identified articles were abstracted, quality assessed and combined into a summary effect. Twelve observational studies containing data of 6,320 pilgrims were included. The compliance of hand washing with non-alcoholic surfactants was 77.7% (ranged from 31.5% to 90.3% in individual studies) and the compliance of hand cleaning with alcoholic products was 44.9% (ranged from 30.7% to 67.4%). Education was a key influencer of hand hygiene practice. Only three of the six studies that assessed the effectiveness of hand hygiene against clinical disease found the practice to be effective, and only one of the two studies that evaluated its effectiveness against a laboratory-confirmed infection found it to be effective. This systematic review suggests that hand hygiene using non-alcoholic products is generally acceptable among Hajj pilgrims but there is no conclusive evidence on its effectiveness.

The Impact of Receiving Pretravel Health Advice on the Prevention of Hajj-Related Illnesses Among Australian Pilgrims: Cohort Study

Background

Pretravel health advice can play a crucial role in improving both travelers’ awareness about disease risk and compliance with preventive measures. General practitioners (GPs) and the internet have been reported internationally to be the main sources of health advice for travelers to non–mass gathering (MG) destinations. However, few studies have attempted to investigate the sources of health advice among travelers to MGs including the Hajj pilgrimage, and none of these studies further investigated the impact of pretravel advice on pilgrims’ health behaviors.

Objective

The objective of this study was to investigate the impact of the source of pretravel health advice (from GPs and specialized Hajj travel agents) on Hajj pilgrims’ awareness of and compliance with health recommendations, and the incidence of Hajj-associated illnesses.

Methods

A prospective cohort study (before and during Hajj) was conducted among Australian pilgrims aged ≥18 years in 2015.

Results

A total of 421 pilgrims participated prior to Hajj, and 391 (93%) provided follow-up data during Hajj. All participants obtained pretravel health advice from one or more sources, with Hajj travel agents (46%) and general practitioners (GPs; 40%) the most commonly reported sources. In total, 288 (74%) participants reported Hajj-related symptoms, of which 86% (248/288) were respiratory symptoms. Participants who obtained pretravel health advice from travel agents were more likely to be aware of the official Saudi recommendations (adjusted odds ratio [aOR] 2.1, 95% CI 1.2-3.8; P=.01), receive recommended vaccines before travel (aOR 2.4, 95% CI 1.4-3.9; P=.01), use hand sanitizers including soap (aOR 2.5, 95% CI 1.1-6.1; P=.03), and wash their hands after touching an ill person during Hajj (aOR 2.9, 95% CI 1.1-7.1; P=.01), compared to those who sought advice from GPs. However, neither advice from travel agents nor GPs was associated with a lower incidence of Hajj-related illnesses.

Conclusions

Advice from travel agents appeared to be accessed by more travelers than that from GPs, and was associated with an increased likelihood of positive travel health behaviors.

Using social media for vaccination promotion: Practices and challenges

OBJECTIVE

Vaccination misinformation is widespread on social media. Vaccine-promoting organisations are working to curb its influence, but face obstacles. We aimed to analyse their social media strategies and the challenges they encounter.

METHODS

In this qualitative study, we purposively sampled 21 participants responsible for social media from vaccine-promoting organisations. We used Framework Analysis to explore the data.

RESULTS

Vaccine-promoting organisations faced obstacles using social media, including fast-paced change, limited resources, and insufficient organisational buy-in. They experienced difficulties reaching audiences, exploiting social media listening, and measuring impact. Consequently, they may miss opportunities to counter misinformation, connect with groups low in vaccine confidence, and determine diverse audience responses. They lack strong evidence linking social media strategies with behaviour change, and have difficulty understanding silent audiences.

CONCLUSIONS

Vaccine-promoting organisations have an opportunity to embrace the participatory nature of social media. They could share listening insights with like-minded groups, and conduct research exploring associations between social media strategies and community attitude/behaviour change. Social media platforms could assist by renewing vaccine-promoting organisations' organic reach, supporting the development of tailored listening and credibility tools, and strengthening collaborations to promote credible content.

How organisations promoting vaccination respond to misinformation on social media: a qualitative investigation

BACKGROUND

Vaccination misinformation is associated with serious public health consequences, such as a decrease in vaccination rates and a risk of disease outbreaks. Although social media offers organisations promoting vaccination unparalleled opportunities to promote evidence and counterbalance misinformation, we know relatively little about their internal workings. The aim of this paper is to explore the strategies, perspectives and experiences of communicators working within such organisations as they promote vaccination and respond to misinformation on social media.

METHODS

Using qualitative methods, we purposively sampled 21 participants responsible for routine social media activity and strategy from Australian organisations actively promoting vaccination on social media, including government health departments, local health services, advocacy groups, professional associations and technical/scientific organisations. We conducted semi-structured, in-depth interviews to explore their perspectives and practices. Applying Risk Communication principles as a lens, we used Framework Analysis to explore the data both inductively and deductively.

RESULTS

Organisations promoting vaccination face multiple challenges on social media, including misinformation, anti-science sentiment, a complex vaccination narrative and anti-vaccine activists. They developed a range of sophisticated strategies in response, including communicating with openness in an evidence-informed way; creating safe spaces to encourage audience dialogue; fostering community partnerships; and countering misinformation with care.

CONCLUSIONS

We recommend that communicators consider directly countering misinformation because of the potential influence on their silent audience, i.e. those observing but not openly commenting, liking or sharing posts. Refutations should be straightforward, succinct and avoid emphasizing misinformation. Communicators should consider pairing scientific evidence with stories that speak to audience beliefs and values. Finally, organisations could enhance vaccine promotion and their own credibility on social media by forming strong links with organisations sharing similar values and goals.

Exploring Australian Hajj Tour Operators' Knowledge and Practices Regarding Pilgrims' Health Risks: A Qualitative Study

Background

Travel agents are known to be one of the main sources of health information for pilgrims, and their advice is associated with positive health behaviors.

Objective

This study aimed to investigate travel agents’ health knowledge, what health advice they provide to the pilgrims, and their sources of health information.

Methods

In-depth interviews were conducted among specialist Hajj travel agents in Sydney, Australia. Thematic analysis was undertaken.

Results

Of the 13 accredited Hajj travel agents, 9 (69%) were interviewed. A high level of awareness regarding gastrointestinal infections, standard hygiene methods, and the risk of injury was noted among the participants and was included in advice provided to pilgrims. However, very limited knowledge and provision of advice about the risk of respiratory infections was identified. Knowledge of the compulsory meningococcal vaccine was high, and all participated travel agents reported influenza vaccine (a recommended vaccine) as a second “compulsory” vaccine for Hajj visas. Conversely, participants reported very limited knowledge about other recommended vaccines for Hajj. The Ministry of Hajj website and personal Hajj experience were the main sources of information.

Conclusions

This study identifies a potential path for novel health promotion strategies to improve health knowledge among Hajj travel agents and subsequently among Hajj pilgrims.

Australian caregivers' perceptions of influenza vaccination in pregnancy: A mixed methods exploration

BACKGROUND

Pregnant women and their unborn children are at high risk from both pandemic and seasonal influenza.

AIM

To explore views about influenza vaccination during pregnancy, in a pandemic and immediate post-pandemic context, among mothers and other carers of young children.

METHODS

In a mixed methods study, caregivers from 16 childcare centres in Sydney, Australia, were surveyed in November and December 2009, and interviews were conducted with caregivers from six childcare centres between June 2009 and May 2011.

FINDINGS

Emerging themes from 41 interviews conducted with mothers included: 'pregnancy as a protected state', 'risk negotiation' and 'centrality of healthcare worker interaction'. Of 972 surveys distributed, 431 were completed (a response rate of 44%). Respondents perceived pandemic influenza risks to be greater for pregnant women than for their unborn children. Only 2% (9/383) of women reported being vaccinated against swine flu during pregnancy and 45% (168/383) indicated intent to receive swine flu vaccination in a future pregnancy.

DISCUSSION

The low rates of maternal influenza vaccination revealed in this study contrast to recent gains in vaccine uptake. Vaccination decision-making in pregnancy can be complex and contextually driven for some women. Healthcare workers, including midwives, have a key role in addressing women's concerns about maternal influenza vaccination in both pandemic and interpandemic periods.

CONCLUSIONS

Policy makers need to be cognisant of women's concerns and develop resources for both pregnant women and healthcare workers as part of both future pandemic planning and seasonal vaccination efforts.

Much ado about flu: A mixed methods study of parental perceptions, trust and information seeking in a pandemic

Background

Effective public health messaging is essential in both the planning phase and duration of a pandemic.

Objectives

This study aimed to gain an understanding of parental information seeking, trusted sources and needs in relation to pandemic influenza A 2009 (pH1N1) to inform future policy planning and resource development.

Patients/Methods

We conducted a mixed methods study; parents from 16 childcare centres in Sydney, Australia, were surveyed between 16 November and 9 December 2009, and interviews were conducted with participants from six childcare centres between June 2009 and May 2011.

Results

From 972 surveys distributed, 431 were completed; a response rate of 44%. Most parents (90%) reported that doctors were “trusted a lot” as a source of influenza information, followed by nurses (59%), government (56%) and childcare centres (52%). Less trusted sources included media (7% selected “trusted a lot”), antivaccination groups (6%) and celebrities (1%). Parents identified a range of key search terms for influenza infection and vaccine. From 42 in‐depth interviews, key themes were as follows: “Action trigger,” “In an emergency, think Emergency,” “Fright to hype” and “Dr Google and beyond.” Parents relied heavily on media messages, but cynicism emerged when the pandemic was milder than expected. Parents viewed a range of information sources as trustworthy, including doctors, authoritative hospital or government websites, and childcare centres and schools.

Conclusions

A user‐centred orientation is vital for pandemic communications including tailored information provision, via trusted sources based on what parents want to know and how they can find it.

Midwives' attitudes, beliefs and concerns about childhood vaccination: A review of the global literature

Vaccine hesitancy in industrialised countries is an area of concern. Health professionals play a significant role in parental vaccination decisions, however, to date the role of midwives has not been widely explored. This review sought to describe the attitudes and communication practices of midwives in developed countries towards childhood vaccines. Medline, Cinahl, PsychInfo, Embase and the grey literature were searched. Inclusion criteria were qualitative and quantitative studies reporting midwives' beliefs, attitudes and communication practices toward childhood vaccination. The search returned 366 articles, of which 359 were excluded by abstract. Two additional articles were identified from the grey literature and references, resulting in nine studies from five countries included in the review. Across the studies, the majority of midwives supported vaccination, although a spectrum of beliefs and concerns emerged. A minority expressed reservations about the scientific justification for vaccination, which focussed on what is not yet known rather than mistrust of current evidence. Most midwives felt that vaccines were safe; a minority were unsure, or believed they were unsafe. The majority of midwives agreed that childhood vaccines are necessary. Among those who expressed doubt, a commonly held opinion was that vaccine preventable diseases such as measles are relatively benign and didn't warrant vaccination against them. Finally, the midwifery model of care was shown to focus on providing individualised care, with parental choice being placed at a premium. The midwifery model care appears to differ in approach from others, possibly due to a difference in the underpinning philosophies. Research is needed to understand how midwives see vaccination, and why there appears to be a spectrum of views on the subject. This information will inform the development of resources tailored to the midwifery model of care, supporting midwives in advocating for childhood vaccination.

An audit of the quality of online immunisation information available to Australian parents

Background

The Internet is increasingly a source of health information for parents, who use the Internet alongside health care providers for immunisation information. Concerns have been raised about the reliability of online immunisation information, however to date there has been no audit of the quality or quantity of what is available to Australian parents. The objective of this study was to address this gap by simulating a general online search for immunisation information, and assessing the quality and quantity of the web sites returned by the search.

Methods

We used Google trends to identify the most common immunisation search terms used in Australia. The ten most common terms were entered into five search engines and the first ten non-commercial results from each search collated. A quality assessment tool was developed using the World Health Organization Global Advisory Committee on Vaccine Safety (GACVS) criteria for assessing the quality of vaccine safety web sites, and used to assess and score the quality of the sites.

Results

Seven hundred web pages were identified, of which 514 were duplicates, leaving 186 pages from 115 web sites which were audited. Forty sites did not include human immunisation information, or presented personal opinion about individuals, and were not scored. Of the 75 sites quality scored, 65 (87%) were supportive of immunisation, while 10 (13%) were not supportive. The overall mean quality score was 57/100 (range 14/100 to 92/100). When stratified by pro and anti-vaccination stance, the average quality score for pro-vaccine sites was 61/100, while the average score for anti-vaccine sites was 30/100.

Pro-vaccine information could be divided into three content groups: generalist overview with little detail; well-articulated and understandable detail; and lengthy and highly technical explanations. The main area found to be lacking in pro-vaccine sites was lack of transparent authorship.

Conclusion

Our findings suggest a need for information which is easily found, transparently authored, well-referenced, and written in a way that is easily understood.

Exploring barriers to and facilitators of preventive measures against infectious diseases among Australian Hajj pilgrims: cross-sectional studies before and after Hajj

OBJECTIVE

For reasons that have yet to be elucidated, the uptake of preventive measures against infectious diseases by Hajj pilgrims is variable. The aim of this study was to identify the preventive advice and interventions received by Australian pilgrims before Hajj, and the barriers to and facilitators of their use during Hajj.

METHODS

Two cross-sectional surveys of Australians pilgrims aged ≥18 years were undertaken, one before and one after the Hajj 2014.

RESULTS

Of 356 pilgrims who completed the survey (response rate 94%), 80% had the influenza vaccine, 30% the pneumococcal vaccine, and 30% the pertussis vaccine. Concern about contracting disease at Hajj was the most cited reason for vaccination (73.4%), and not being aware of vaccine availability was the main reason for non-receipt (56%). Those who obtained pre-travel advice were twice as likely to be vaccinated as those who did not seek advice. Of 150 pilgrims surveyed upon return, 94% reported practicing hand hygiene during Hajj, citing ease of use (67%) and belief in its effectiveness (62.4%) as the main reasons for compliance; university education was a significant predictor of hand hygiene adherence. Fifty-three percent used facemasks, with breathing discomfort (76%) and a feeling of suffocation (40%) being the main obstacles to compliance.

CONCLUSION

This study indicates that there are significant opportunities to improve awareness among Australian Hajj pilgrims about the importance of using preventive health measures.

Association between Australian Hajj Pilgrims' awareness of MERS-CoV, and their compliance with preventive measures and exposure to camels

Through a prospective cohort study the relationship between travellers' awareness of MERS-CoV, and compliance with preventive measures and exposure to camels was evaluated among Australian Hajj pilgrims who attended Hajj in 2015. Only 28% of Australian Hajj pilgrims were aware of MERS-CoV in Saudi Arabia. Those who were aware of MERS-CoV were more likely to receive recommended vaccines [odds ratio (OR) 3.1, 95% confidence interval (CI): 1.5-5.9, P < 0.01], but there was no significant difference in avoiding camels or their raw products during Hajj between those who were aware of MERS-CoV and those who were not (OR 1.2, 95% CI: 0.3-5.2, P = 0.7). Hajj pilgrims' awareness is reflected in some of their practices but not in all.

Australian Hajj pilgrims' knowledge, attitude and perception about Ebola, November 2014 to February 2015

Upon return from Hajj 2014, 150 Australian pilgrims were interviewed about their understanding of the Ebola epidemic. Most (89%, 134/150) knew of the epidemic before travelling and 60% (80/134) of those knew Ebola transmits through body fluids. Pilgrims who received pre-travel health advice were more conscious of Ebola (69% vs 31%, p = 0.01) and adhered better to hand hygiene after touching an ill person (68% vs 31%, p < 0.01). Mass media was the main information source (78%).

Understanding pregnant women's attitudes and behavior toward influenza and pertussis vaccination

Internationally, pregnant and postpartum women have been the focus of influenza and pertussis immunization campaigns, with differing levels of vaccine acceptance. We used semistructured interviews to explore pregnant women's perspectives on influenza vaccination during pregnancy and postpartum pertussis vaccination. Many women saw pregnancy as a busy time filled with advice on what they "should" and "should not" do to ensure the health of their fetus, and vaccinating themselves was regarded as just one of these tasks needing consideration. Women were more concerned about potential risks to their infants' health before their own. They saw influenza as a disease affecting the mother, whereas they viewed pertussis as a threat to the baby and therefore comparatively more risky. They were thus more likely to intend to vaccinate against pertussis to protect their infant. Framing of vaccination information toward protection of the baby might help increase vaccine uptake among pregnant women.

Uptake of influenza vaccine by pregnant women: a cross-sectional survey

OBJECTIVES

To determine influenza vaccination coverage among pregnant women in New South Wales, and factors associated with vaccine uptake during pregnancy.

DESIGN, SETTING AND PARTICIPANTS

Quantitative self-administered survey of pregnant women, using a non-random, stratified sample from antenatal clinics at three demographically diverse hospitals in NSW during the influenza season of 2011.

MAIN OUTCOME MEASURES

Self-reported influenza vaccine uptake while pregnant; and attitudes, barriers and facilitators to vaccine acceptance during pregnancy.

RESULTS

Of 939 women approached, 815 participated (87%). Influenza vaccine uptake in pregnant women was 27%. Women who had received a recommendation to have the vaccine were 20.0 times (95% CI, 10.9-36.9) more likely to have been vaccinated. Forty-two per cent recalled receiving a recommendation to be vaccinated. Other factors associated with vaccination were study site, perceived infection severity, overall feelings toward vaccination during pregnancy, vaccine accessibility, and willingness to take up the vaccine if recommended. Concern about the baby's safety was negatively associated with vaccination (odds ratio, 0.5; 95% CI, 0.2-0.9), but 68% (95% CI, 63%-71%) of women who expressed concern agreed they would have the vaccine if their health care professional recommended it.

CONCLUSION

Recommendation from a health care provider is strongly associated with influenza vaccine uptake among pregnant women and can overcome their concerns about safety, but less than half the women surveyed reported receiving such a recommendation. Educational material targeting pregnant women and professional education and support for antenatal health care providers are needed to increase awareness and recommendation.

Sources of pertussis infection in young infants: a review of key evidence informing targeting of the cocoon strategy

BACKGROUND

The relative contribution of different categories of contact in transmitting pertussis to very young infants, who experience the most severe morbidity, is the most important single factor determining the likely benefit of pertussis vaccination of their close contacts (the "cocooning" strategy).

OBJECTIVE

To identify, evaluate the quality of and summarise existing data on potential sources of infant pertussis infection in high income countries, focussing on infants under 6 months old.

DATA SOURCES

Online databases MEDLINE and EMBASE. Additional studies were identified from the reference lists of relevant articles. Study selection and analysis: Study quality was evaluated by standardised criteria, based on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement. Pooled estimates of the proportion of pertussis cases attributable to various contact sources were calculated using data from the highest quality studies.

RESULTS

Nine studies met the inclusion criteria; seven included data on contacts of hospitalised infants less than 6 months old. Case definitions and methods of contact ascertainment were variable. Most identified sources were from the household, of which 39% (95%CI 33-45%) were mothers, 16% (95%CI 12-21%) fathers, and 5% (95%CI 2-10%) grandparents. Estimates for siblings (16-43%) and non-household contacts (4-22%) were more heterogeneous. For 32-52% of infant cases, no source was identified. Asymptomatic pertussis infection was found in 8-13% of contacts evaluated.

CONCLUSIONS

These data suggest that the greatest potential impact of pertussis vaccination of adults to prevent severe disease in young infants comes from vaccinating mothers, followed by fathers, with grandparents having a minor role. Siblings varied in importance and, given recent data regarding waning immunity in vaccinated children, need further study. Non-household sources are also well documented, highlighting the potential limitations of the cocoon strategy to prevent severe infant disease.

Hereditary prostate cancer in African American families: linkage analysis using markers that map to five candidate susceptibility loci

African American men have the highest incidence of prostate cancer in the world. Despite this statistic, linkage studies designed to localise prostate cancer susceptibility alleles have included primarily men of Caucasian descent. In this report, we performed a linkage analysis using 33 African American prostate cancer families from two independent research groups. In total, 126 individuals (including 89 men with prostate cancer) were genotyped using markers that map to five prostate cancer susceptibility loci, namely HPC1 at 1q24–25, PCAP at 1q42.2–43, CAPB at 1p36, HPC20 on chromosome 20, and HPCX at Xq27–28. Multipoint mode-of-inheritance-free linkage analyses were performed using the GENEHUNTER software. Some evidence of prostate cancer was detected to HPC1 using all families with a maximum NPL Z score of 1.12 near marker D1S413 (P=0.13). Increased evidence of linkage was observed in the 24 families with prostate cancer diagnosis prior to age 65 years and in the 20 families with male-to-male transmission. Some evidence of prostate cancer linkage was also detected at markers mapping to PCAP, HPC20, and HPCX. Continued collection and analysis of African American prostate cancer families will lead to an improved understanding of inherited susceptibility in this high-risk group.

Polymorphisms in the CYP1B1 gene are associated with increased risk of prostate cancer

CYP1B1 has been evaluated as a candidate gene for various cancers because of its function in activating environmental procarcinogens and catalysing the conversion of oestrogens to genotoxic catechol oestrogens. To test the hypothesis that genetic polymorphisms in the CYP1B1 gene may associate with the risk for prostate cancer (CaP), we compared the allele, genotype, and haplotype frequencies of 13 single nucleotide polymorphisms (SNPs) of CYP1B1 among 159 hereditary prostate cancer (HPC) probands, 245 sporadic CaP cases, and 222 unaffected men. When each of the SNPs was analysed separately, marginally significant differences were observed for allele frequencies between sporadic cases and controls for three consecutive SNPs (−1001C/T, −263G/A, and −13C/T, P=0.04–0.07). Similarly, marginally significant differences between sporadic cases and controls in the frequency of variant allele carriers were observed for five consecutive SNPs (−1001C/T, −263G/A, −13C/T, +142C/G, and +355G/T, P=0.02–0.08). Interestingly, when the combination of these five SNPs was analysed using a haplotype approach, a larger difference was found (P=0.009). One frequent haplotype (C-G-C-C-G of −1001C/T, −263G/A, −13C/T, +142C/G, and +355G/T) was associated with an increased risk for CaP, while the other frequent haplotype (T-A-T-G-T) was associated with a decreased risk for CaP. These findings suggest that genetic polymorphisms in CYP1B1 may modify the risk for CaP.

Discovery of recently adopted orphan receptors for apelin, urotensin II, and ghrelin identified using novel radioligands and functional role in the human cardiovascular system

Using novel synthetic radioligands, we have discovered receptors for the recently paired apelin (APJ orphan receptor), ghrelin (GHS orphan receptor), and urotensin II (orphan GPR14) in the human cardiovascular system and determined their anatomical localisation. In addition, we have established functional vasoactive properties for these three peptides as potential vasoconstrictor/vasodilator mediators and provided evidence for alteration of receptor density in cardiovascular disease. We find that receptors for apelin, ghrelin, and urotensin II are widely distributed in human cardiovascular tissue, suggesting perhaps vasoactive roles for these peptides in human vascular physiology and a potential role in pathophysiology. Apelin and urotensin II are potent vasoconstrictors with low efficacy, consistent with their low receptor density. Ghrelin receptor density was increased (approximately three- to fourfold) with atherosclerosis of coronary artery disease and accelerated atherosclerosis of saphenous vein grafts, compared with normal vessels, highlighting a potentially beneficial role for this novel vasodilator peptide in human vascular disease. Our approach has demonstrated one successful strategy for translating genetic information encoding recently paired orphan receptor ligands into discovery of function. This study has the advantage of focussing on the actual disease processes, which allow the more precise identification of novel therapeutic targets.

Linkage and association of CYP17 gene in hereditary and sporadic prostate cancer

Androgens are essential for prostate development, growth and maintenance and the association between androgen levels and prostate cancer is well established. Since the CYP17 gene encodes the enzyme cytochrome P450c17alpha, which mediates 17alpha-hydroxylase and 17,20-lyase activities in the androgen biosynthesis pathway, sequence variations in the gene and association with increased risk to prostate cancer has been studied. In particular, several groups have studied the association between a polymorphism in the 5' promoter region and prostate cancer using a population-based association approach. However, the results from these studies were inconclusive. To further study this polymorphism and its possible role in hereditary prostate cancer (HPC), we performed a genetic linkage analysis and family-based association analysis in 159 families, each of which contains at least 3 first-degree relatives with prostate cancer. In addition, we performed a population-based association analysis to compare the risk of this polymorphism to hereditary and sporadic prostate cancer in 159 HPC probands, 249 sporadic prostate cancer patients and 211 unaffected control subjects. Evidence for linkage at the CYP17 gene region was found in the total 159 HPC families (LOD = 1.3, p = 0.01, at marker D10S222). However, family-based association tests did not provide evidence for overtransmission of either allele of the CYP17 polymorphism to affected individuals in the HPC families. The allele and genotype frequencies of the polymorphism were not statistically different among the HPC probands, sporadic cases and unaffected control subjects. In conclusion, our results suggest that the CYP17 gene or other genes in the region may increase the susceptibility to prostate cancer in men; however, the polymorphism in the 5' promoter region has a minor role if any in increasing prostate cancer susceptibility in our study sample.

Physiological antagonism of endothelin-1 in human conductance and resistance coronary artery

The ability of four endogenous vasodilators, nitric oxide (NO; 0.01 - 30 microM), atrial (ANP), brain (BNP) and C-type (CNP) natriuretic peptide (0.1 - 300 nM), to reverse endothelin-1 (ET-1; 10 nM) constrictions in human resistance and conductance coronary arteries (CA) in vitro was investigated. ET-1 (0.1 - 300 nM) constricted resistance CA more potently than conductance CA (P<0.05; EC(50) values 2.98 nM (95% CI: 1.49 - 5.95 nM and 8.58 (4.72 - 15.6 nM) respectively)). The NO-donor diethylamine NONOate fully reversed the ET-1 constriction in conductance CA (E(MAX) 127+/-9.16%), however only partial reversal was observed in resistance CA (E(MAX) 78.8+/-8.13; P<0.05). The soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (100 microM) reduced the maximum response to diethylamine NONOate to 76.9+/-14.4% in conductance CA (P<0.05), but had no effect on resistance CA (E(MAX) 77.2+/-18.4%). There was no difference between responses to ANP in conductance and resistance CA (EC(50) values 4.25 nM (0.84 - 21.4 nM) and 18.4 nM (2.92 - 116 nM), E(MAX) 53.1+/-14.7% and 48.6+/-11.8% respectively). BNP was a more potent vasodilator of conductance than resistance CA. In conductance CA the mean EC(50) value was 2.4 nM (0.74 - 7.75 nM), E(MAX) 54.5+/-14.9%. Concentration-response curves to BNP were incomplete in resistance CA. Concentration-response curves to CNP were incomplete in both conductance and resistance CA. The greater potency of ET-1 in resistance vessels may exacerbate the effects of increased circulating levels of the peptide in disease. Only NO could fully reverse ET-1 mediated constrictions in conductance CA, and none of the dilators tested could completely counteract constrictions in resistance CA.

Linkage of prostate cancer susceptibility loci to chromosome 1

Three prostate cancer susceptibility genes have been reported to be linked to different regions on chromosome 1: HPC1 at 1q24-25, PCAP at 1q42-43, and CAPB at 1p36. Replication studies analyzing each of these regions have yielded inconsistent results. To evaluate linkage across this chromosome systematically, we performed multipoint linkage analyses with 50 microsatellite markers spanning chromosome 1 in 159 hereditary prostate cancer families (HPC), including 79 families analyzed in the original report describing HPC1 linkage. The highest lod scores for the complete dataset of 159 families were observed at 1q24-25 at which the parametric lod score assuming heterogeneity (hlod) was 2.54 (P=0.0006) with an allele sharing lod of 2.34 (P=0.001) at marker D1S413, although only weak evidence was observed in the 80 families not previously analyzed for this region (hlod=0.44, P=0.14, and allele sharing lod=0.67, P=0.08). In the complete data set, the evidence for linkage across this region was very broad, with allele sharing lod scores greater than 0.5 extending approximately 100 cM from 1p13 to 1q32, possibly indicating the presence of multiple susceptibility genes. Elsewhere on chromosome 1, some evidence of linkage was observed at 1q42-43, with a peak allele sharing lod of 0.56 (P=0.11) and hlod of 0.24 (P=0.25) at D1S235. For analysis of the CAPB locus at 1p36, we focused on six HPC families in our collection with a history of primary brain cancer; four of these families had positive linkage results at 1p36, with a peak allele sharing lod of 0.61 (P=0.09) and hlod of 0.39 (P=0.16) at D1S407 in all six families. These results are consistent with the heterogeneous nature of hereditary prostate cancer, and the existence of multiple loci on chromosome 1 for this disease.

Nitric oxide-mediated modulation of the endothelin-1 signalling pathway in the human cardiovascular system

1. We studied the ability of nitric oxide (NO) to physiologically antagonize endothelin-1 (ET-1) induced constrictions in human internal mammary artery (IMA). We also investigated the hypothesis that NO interacts directly with ET-receptor binding in human heart and aorta. 2. ET-1 potently contracted IMA (EC(50) 6.86 nM, 95% CI: 3.5 - 13.4 nM; n=12). The constrictor response to 10 nM ET-1 was fully reversed by the NO-donor diethylamine NONOate (DEA/NO; EC(50) 2.0 microM, 95% CI: 0.8 - 4.8 microM; n=5). The guanylate cyclase inhibitor ODQ (100 microM) reduced the response to DEA/NO but did not abolish it (E(MAX) 50.9+/-8.5% in the presence of ODQ; 113.0+/-8.4%, control). 3. The increase in cyclic GMP by 30 microM DEA/NO was abolished in the presence of 100 microM ODQ (n=6). 4. In saturation binding experiments the NO-donor Diethyltriamine NONOate (DETA/NO; 1 mM) caused a 90% reduction in maximum binding of [(125)I]-ET-1 in human heart, without affecting the affinity. This reduction in binding was abolished by haemoglobin. Pre-incubating either the radiolabel or the tissue with NO-donors did not reduce binding. A similar effect was observed in aortic smooth muscle. 5. We have shown that DEA/NO is able to reverse ET-1-induced contractions in the human vasculature. The binding studies suggest a direct interaction between NO and the ET receptor or receptor-ligand complex in human ventricular and aortic tissue. NO is released continuously in vivo, thus this apparent modification of ET-receptor binding may provide an additional mechanism by which NO counter-balances the effects of ET.

Novel nitric oxide donors reverse endothelin-1-mediated constriction in human blood vessels

Cardiovascular disease is associated with elevated circulating plasma levels of endothelin-1 (ET-1). Our aim was to compare the ability of the nitric oxide donors (NO-donors) 3-morpholinylsydnonimine (SIN-1) and S-nitroso-N-acetylpenicillamine (SNAP) with the novel nitric oxide donors (NONOates) diethylamine NONOate (DEA/NO), and diethylenetriamine NONOate (DETA/NO) in order to physiologically antagonize ET-1-mediated constriction of human internal mammary arteries (IMA) in vitro. Both SNAP and DETA/NO caused a significant rightward shift in the ET-1 concentration-response curve. All four NO-donors were found to completely reverse an established contraction to a submaximal concentration ET-1 (decreasing order potency: SNAP >DEA/NO > SIN-1 > DETA/NO). These data suggest that the NONOates DEA/NO and DETA/NO can physiologically antagonize the effects of ET-1 in human arteries and may prove to be useful therapeutic agents in the treatment of cardiovascular disease.

Evidence that different mechanisms underlie smooth muscle relaxation to nitric oxide and nitric oxide donors in the rabbit isolated carotid artery

1. The endothelium-dependent relaxants acetylcholine (ACh; 0.03-10 microM) and A23187 (0.03-10 microM), and nitric oxide (NO), applied either as authentic NO (0.01-10 microM) or as the NO donors 3-morpholino-sydnonimine (SIN-1; 0.1-10 microM) and S-nitroso-N-acetylpenicillamine (SNAP; 0.1-10 microM), each evoked concentration-dependent relaxation in phenylephrine stimulated (1-3 microM; mean contraction and depolarization, 45.8+/-5.3 mV and 31.5+/-3.3 mN; n=10) segments of rabbit isolated carotid artery. In each case, relaxation closely correlated with repolarization of the smooth muscle membrane potential and stimulated a maximal reversal of around 95% and 98% of the phenylephrine-induced depolarization and contraction, respectively. 2. In tissues stimulated with 30 mM KCl rather than phenylephrine, smooth muscle hyperpolarization and relaxation to ACh, A23187, authentic NO and the NO donors were dissociated. Whereas the hyperpolarization was reduced by 75-80% to around a total of 10 mV, relaxation was only inhibited by 35% (n=4-7 in each case; P<0.01). The responses which persisted to ACh and A23187 in the presence of 30 mM KCl were abolished by either the NO synthase inhibitor L-NG-nitroarginine methyl ester (L-NAME; 100 microM) or the inhibitor of soluble guanylyl cyclase 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 10 microM; 10 min; n=4 in each case; P<0.01). 3. Exposure to ODQ significantly attenuated both repolarization and relaxation to ACh, A23187 and authentic NO, reducing the maximum changes in both membrane potential and tension to each relaxant to around 60% of control values (n=4 in each case; P<0.01). In contrast, ODQ almost completely inhibited repolarization and relaxation to SIN-1 and SNAP, reducing the maximum responses to around 8% in each case (n=3-5; P<0.01). 4. The potassium channel blockers glibenclamide (10 microM), iberiotoxin (100 nM) and apamin (50 nM), alone or in combination, had no significant effect on relaxation to ACh, A23187, authentic NO, or the NO donors SIN-1 and SNAP (n=4 in each case; P>0.05). Charybdotoxin (ChTX; 50 nM) almost abolished repolarization to ACh (n=4; P<0.01) and inhibited the maximum relaxation to ACh, A23187 and authentic NO each by 30% (n=4-8; P<0.01). Application of ODQ (10 microM; 10 min) abolished the ChTX-insensitive responses to ACh, A23187 and authentic NO (n=4 in each case; P<0.01 5. When the concentration of phenylephrine was reduced (to 0.3-0.5 microM) to ensure the level of smooth muscle contraction was the same as in the absence of potassium channel blocker, ChTX had no effect on the subsequent relaxation to SIN-1 (n=4; P>0.05). However, in the presence of tone induced by 1-3 microM phenylephrine (51.2+/-3.3 mN; n=4), ChTX significantly reduced relaxation to SIN-1 by nearly 50% (maximum relaxation 53.2+/-6.3%, n=4; P<0.01). 6. These data indicate that NO-evoked relaxation of the rabbit isolated carotid artery can be mediated by three distinct mechanisms: (a) a cyclic GMP-dependent, voltage-independent pathway, (b) cyclic GMP-mediated smooth muscle repolarization and (c) cyclic GMP-independent, ChTX-sensitive smooth muscle repolarization. Relaxation and repolarization to both authentic and endothelium-derived NO in this large conduit artery appear to be mediated by parallel cyclic GMP-dependent and -independent pathways. In contrast, relaxation to the NO-donors SIN-1 and SNAP appears to be mediated entirely via cyclic GMP-dependent mechanisms.