The risk of cognitive decline and dementia in older adults diagnosed with COVID-19: A systematic review and meta-analysis.

BACKGROUND: Cognitive impairment can be caused by infections with various pathogens, including SARS-CoV-2. Research has yet to determine the true incidence and course of cognitive impairment in older adults following COVID-19. Furthermore, research has theorised that COVID-19 is associated with dementia progression and diagnosis but this association has yet to be fully described. METHODS: A systematic review was registered in Prospero and conducted on the databases PubMed, Embase, Ovid, CENTRAL and Cochrane Library. Studies reporting cognitive impairment and dementia outcomes in post-acute and post-COVID-19 patients aged ≥65 years, and which included control data, were included in this review. RESULTS: 15,124 articles were identified by the search strategy. After eliminating duplicate titles and completing title, abstracts and full-text review, 18 studies were included comprising of 412,957 patients with COVID-19 (46.63% male) and 411,929 patients without COVID-19 (46.59% male). The overall mean Montreal Cognitive Assessment (MoCA) score in COVID-19 patients was 23.34 out of 30 (95% CI [22.24, 24.43]). indicating cognitive impairment. The overall proportion of patients identified as having new onset cognitive impairment was 65% (95% CI [44, 81]). Subgroup analyses indicated that time since infection significantly improves overall MoCA score and reduces proportion of patients with cognitive impairment. CONCLUSION: This study indicates that cognitive impairment may be an important sequela of COVID-19. Further research with adequate sample sizes is warranted regarding COVID-19's association with new-onset dementia and dementia progression, and the effect of repeat infections. There is a need for development of diagnostic and management protocols for COVID-19 patients with cognitive impairment.

The public health and economic burden of long COVID in Australia, 2022-24: a modelling study.

OBJECTIVE: To estimate the number of people in Australia with long COVID by age group, and the associated medium term productivity and economic losses. STUDY DESIGN: Modelling study: a susceptible-exposed-infected-recovered (SEIR) model to estimate the number of people with long COVID over time following single infections, and a labour supply model to estimate productivity losses as a proportion of gross domestic product (GDP). SETTING: Australia, 2022-2024. MAIN OUTCOME MEASURES: Estimated number of people infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during 2022-2023 (based on serosurvey data) who have long COVID, 2022-2024, by age group; estimated GDP loss during 2022 caused by reduced labour supply attributable to long COVID. RESULTS: Our model projected that the number of people with long COVID following a single infection in 2022 would peak in September 2022, when 310 341-1 374 805 people (1.2-5.4% of Australians) would have symptoms of long COVID, declining to 172 530-872 799 people (0.7-3.4%) in December 2024, including 7902-30 002 children aged 0-4 years (0.6-2.2%). The estimated mean labour loss attributable to long COVID in 2022 was projected to be 102.4 million (95% confidence interval [CI], 50.4-162.2 million) worked hours, equivalent to 0.48% (95% CI, 0.24-0.76%) of total worked hours in Australia during the 2020-21 financial year. The estimated mean GDP loss caused by the projected decline in labour supply and reduced use of other production factors was $9.6 billion (95% CI, $4.7-15.2 billion), or 0.5% of GDP. The estimated labour loss was greatest for people aged 30-39 years (27.5 million [95% CI, 16.0-41.0 million] hours; 26.9% of total labour loss) and people aged 40-49 years (24.5 million [95% CI, 12.1-38.7 million] hours; 23.9% of total labour loss). CONCLUSION: Widespread SARS-CoV-2 infections in Australia mean that even a small proportion of infected people developing long COVID-related illness and disability could have important population health and economic effects. A paradigm shift is needed, from a sole focus on the immediate effects of coronavirus disease 2019 (COVID-19) to preventing and treating COVID-19 and treating long COVID, with implications for vaccine and antiviral policy and other mitigation of COVID-19.

Public health management of pertussis in adults: Practical challenges and future strategies.

A panel of 24 international experts met in July 2022 to discuss challenges associated with pertussis detection, monitoring, and vaccination in adults; conclusions from this meeting are presented. There has been a shift in the epidemiology of pertussis toward older children and adults. This shift has been attributed to the waning of infection- or vaccine-induced immunity, newer detection techniques causing detection bias, and possibly the replacement of whole-cell pertussis with acellular vaccines in high-income countries, which may lead to immunity waning more quickly. The burden of adult pertussis is still likely under-ascertained due to widespread under-recognition by healthcare professionals (HCPs), under-diagnosis, and under-reporting in this age group. Non-standardized testing guidance and varied case definitions have contributed to under-reporting. Key barriers to HCP engagement with the tetanus, diphtheria, and pertussis (Tdap) vaccine include low awareness, lack of time/funding, and lack of motivation due to low prioritization of Tdap.

Prevalence of influenza and other acute respiratory illnesses in patients with acute myocardial infarction in Bangladesh: A cross-sectional study.

Background and Aims: Several studies imply that influenza and other respiratory illnesses could lead to acute myocardial infarction (AMI), but data from low-income countries are scarce. We investigated the prevalence of recent respiratory illnesses and confirmed influenza in AMI patients, while also exploring their relationship with infarction severity as defined by ST-elevation MI (STEMI) or high troponin levels. Methods: This cross-sectional study, held at a Dhaka tertiary hospital from May 2017 to October 2018, involved AMI inpatients. The study examined self-reported clinical respiratory illnesses (CRI) in the week before AMI onset and confirmed influenza using baseline real-time reverse transcription polymerase chain reaction (qRT-PCR). Results: Of 744 patients, 11.3% reported a recent CRI, most prominently during the 2017 influenza season (35.7%). qRT-PCR testing found evidence of influenza in 1.5% of 546 patients, with all positives among STEMI cases. Frequencies of CRI were higher in patients with STEMI and in those with high troponin levels, although these relationships were not statistically significant after adjusting for other variables. The risk of STEMI was significantly greater during influenza seasons in the unadjusted analysis (relative risk: 1.09, 95% confidence interval [CI]: 1.02-1.18), however, this relationship was not significant in the adjusted analysis (adjusted relative risk: 1.03, 95% CI: 0.91-1.16). Conclusion: In Bangladesh, many AMI patients had a recent respiratory illness history, with some showing evidence of influenza. However, these illnesses showed no significant relationship to AMI severity. Further research is needed to understand these relationships better and to investigate the potential benefits of infection control measures and influenza vaccinations in reducing AMI incidence.

Application of the Modified Grunow-Finke Risk Assessment Tool to the Sverdlovsk Anthrax Outbreak of 1979.

INTRODUCTION: The modified Grunow-Finke tool (mGFT) is an improved scoring system for distinguishing unnatural outbreaks from natural ones. The 1979 Sverdlovsk anthrax outbreak was due to the inhalation of anthrax spores from a military laboratory, confirmed by Russian President Boris Yeltsin in 1992. At the time the Soviet Union insisted that the outbreak was caused by meat contaminated by diseased animals. At the time there was no available risk assessment tool capable of thoroughly examine the origin of the outbreak. METHODS: This study aimed to retrospectively apply the mGFT to test its ability to correctly identify the origin of the Sverdlovsk anthrax outbreak of 1979 as unnatural, using data available up to 1992, before the disclosure of a laboratory leak. Data spanning from 1979 to 1992 were collected through literature reviews. Evidence related to each mGFT criterion was scored on a scale of 0 to 3 and independently reviewed by 3 assessors. These scores were then multiplied with a weighting factor and summed to obtain a maximum score. A final score exceeding 30 was indicative of an unnatural origin. RESULTS: The mGFT results assigned a total of 47 points to the Sverdlovsk anthrax outbreak, suggesting an unnatural origin with a 78% likelihood. CONCLUSIONS: These findings align with the confirmed unnatural origin of the outbreak, highlighting the value of tools such as the mGFT in identifying unnatural outbreaks. Such tools integrate both intelligence evidence and biological evidence in the identification of unnatural outbreaks. The use of such tools for identifying unnatural outbreaks is limited. Outbreak investigation can be improved if risk assessment tools become integral to routine public health practice and outbreak investigations.

Masks and respirators for prevention of respiratory infections: a state of the science review.

SUMMARYThis narrative review and meta-analysis summarizes a broad evidence base on the benefits-and also the practicalities, disbenefits, harms and personal, sociocultural and environmental impacts-of masks and masking. Our synthesis of evidence from over 100 published reviews and selected primary studies, including re-analyzing contested meta-analyses of key clinical trials, produced seven key findings. First, there is strong and consistent evidence for airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory pathogens. Second, masks are, if correctly and consistently worn, effective in reducing transmission of respiratory diseases and show a dose-response effect. Third, respirators are significantly more effective than medical or cloth masks. Fourth, mask mandates are, overall, effective in reducing community transmission of respiratory pathogens. Fifth, masks are important sociocultural symbols; non-adherence to masking is sometimes linked to political and ideological beliefs and to widely circulated mis- or disinformation. Sixth, while there is much evidence that masks are not generally harmful to the general population, masking may be relatively contraindicated in individuals with certain medical conditions, who may require exemption. Furthermore, certain groups (notably D/deaf people) are disadvantaged when others are masked. Finally, there are risks to the environment from single-use masks and respirators. We propose an agenda for future research, including improved characterization of the situations in which masking should be recommended or mandated; attention to comfort and acceptability; generalized and disability-focused communication support in settings where masks are worn; and development and testing of novel materials and designs for improved filtration, breathability, and environmental impact.

Predicting vaccine effectiveness for mpox.

The Modified Vaccinia Ankara vaccine developed by Bavarian Nordic (MVA-BN) was widely deployed to prevent mpox during the 2022 global outbreak. This vaccine was initially approved for mpox based on its reported immunogenicity (from phase I/II trials) and effectiveness in animal models, rather than evidence of clinical efficacy. However, no validated correlate of protection after vaccination has been identified. Here we performed a systematic search and meta-analysis of the available data to test whether vaccinia-binding ELISA endpoint titer is predictive of vaccine effectiveness against mpox. We observe a significant correlation between vaccine effectiveness and vaccinia-binding antibody titers, consistent with the existing assumption that antibody levels may be a correlate of protection. Combining this data with analysis of antibody kinetics after vaccination, we predict the durability of protection after vaccination and the impact of dose spacing. We find that delaying the second dose of MVA-BN vaccination will provide more durable protection and may be optimal in an outbreak with limited vaccine stock. Although further work is required to validate this correlate, this study provides a quantitative evidence-based approach for using antibody measurements to predict the effectiveness of mpox vaccination.

Determinants of uptake of influenza, zoster and pneumococcal vaccines in patients with cardiovascular diseases.

BACKGROUND: Globally, cardiovascular disease (CVD) is the leading cause of death and illness. Vaccine-preventable infections may increase acute coronary vascular disease events and the risk of complications. Low vaccine coverage has been reported among adults at high risk of complications from vaccine-preventable infections. There is a gap in research evidence around determinants of uptake of vaccines among adults with CVD. This study examined the uptake of influenza, pneumococcal and zoster vaccines and the determinants of uptake of the vaccines among cardiac patients. METHOD: A prospective cross-sectional study was carried out among hospitalised cardiac patients through an interviewer-administered questionnaire. Descriptive statistics were used to investigate self-reported uptake of influenza, pneumococcal and zoster vaccines. Univariate and multivariate analyses of participants' social demographic and clinical characteristics were conducted to identify factors for receiving influenza vaccine. RESULTS: Low vaccination rates among 104 participants were found for influenza (45.2%), pneumococcal (13.5%) and zoster (5.8%) vaccines. The most common reason for not receiving influenza vaccine was concern about side effects. Lack of awareness about the pneumococcal and zoster vaccines was the main reason for the poor uptake of these vaccines. Australia-born participants were more likely to receive influenza vaccine than overseas-born participants. Working-age participants and, interestingly, people living with a current smoker were less likely to receive influenza vaccine. CONCLUSION: Influenza, pneumococcal and zoster vaccine uptake among cardiac patients was low. Encouraging physician recommendations for vaccination for cardiac patients under 65 years of age and addressing vaccination challenges among people from culturally and linguistically diverse backgrounds and pharmacy, workplace, and hospital vaccination may help increase vaccination uptake among cardiac patients.

Understanding the impact of adult pertussis and current approaches to vaccination: A narrative review and expert panel recommendations.

Pertussis has several notable consequences, causing economic burden, increased strain on healthcare facilities, and reductions in quality of life. Recent years have seen a trend toward an increase in pertussis cases affecting older children and adults. To boost immunity, and protect vulnerable populations, an enduring approach to vaccination has been proposed, but gaps remain in the evidence surrounding adult vaccination that are needed to inform such a policy. Gaps include: the true incidence of pertussis and its complications in adults; regional variations in disease recognition and reporting; and incidence of severe disease, hospitalizations, and deaths in older adults. Better data on the efficacy/effectiveness of pertussis vaccination in adults, duration of protection, and factors leading to poor vaccine uptake are needed. Addressing the critical evidence gaps will help highlight important areas of unmet need and justify the importance of adult pertussis vaccination to healthcare professionals, policymakers, and payers.

Reducing airborne transmissible diseases in perioperative environments.

The COVID-19 pandemic has transformed our understanding of aerosol transmissible disease and the measures required to minimise transmission. Anaesthesia providers are often in close proximity to patients and other hospital staff for prolonged periods while working in operating and procedure rooms. Although enhanced ventilation provides some protection from aerosol transmissible disease in these work areas, close proximity and long duration of exposure have the opposite effect. Surgical masks provide only minimal additional protection. Surgical patients are also at risk from viral and bacterial aerosols. Despite having recently experienced the most significant pandemic in 100 yr, we continue to lack adequate understanding of the true risks encountered from aerosol transmissible diseases in the operating room, and the best course of action to protect patients and healthcare workers from them in the future. Nevertheless, hospitals can take specific actions now by providing respirators for routine use, encouraging staff to utilise respirators routinely, establishing triggers for situations that require respirator use, educating staff concerning the prevention of aerosol transmissible diseases, and providing portable air purifiers for perioperative spaces with low levels of ventilation.

Cost-benefit of influenza vaccination in preventing sudden cardiac arrest amongst Australian adults.

OBJECTIVE: The objective of the study was to estimate the economic cost benefit of funding influenza vaccination to all Australian adults 50-64 years and predict its effect on sudden cardiac arrest (SCA) deaths and hospitalisation. METHODS: We combined SCA hospitalisation data from the Australian Institute of Health and Welfare (AIHW) with survival, vaccination, and cost parameters from published literature to create a model estimating the cost benefit of universally funded influenza vaccinations to prevent SCA deaths and hospitalisation. Costs were considered from a government perspective and included cost of vaccines and GP consultations, whilst averted deaths were estimated through the age-adjusted value of a statistical life. RESULTS: The target policy was estimated to prevent 278 SCA hospitalisations and 1269 SCA deaths. This would result in cost-savings of almost $4 billion annually, with an incremental benefit-cost ratio (BCR) of 59.94. The majority of savings were associate with averted deaths. When a sensitivity analysis was performed by altering statistical life year values and reducing life years left, the cost-saving remained significant with a minimum BCR of 29.97 derived. CONCLUSIONS: Reducing SCA through extended vaccination including adults 50-64 years is likely to be a cost beneficial policy from a governmental perspective. SCA deaths account for a significant economic loss due to the high mortality rate, which was far greater than the costs saved through averted hospitalisations. More accurate parameters are needed to improve the reliability of these estimate; however, this model can be used as a basis for further research into the economic impact of SCA.

Measles, mumps, rubella and varicella antibodies among international and domestic university students.

BACKGROUND: Vaccine-preventable infections are generally well controlled in Australia. However, gaps in immunity can lead to outbreaks and are important to identify. Young adults are a highly mobile population and a potential source of imported infections. We aimed to evaluate anti- measles, mumps, rubella and varicella (MMR&V) IgG seroprevalence and explore factors relating to antibody seropositivity. METHODS: A cross-sectional online survey was conducted among students from a large Australian university to collect demographic, vaccination, infection and travel characteristics. Blood samples were collected to measure MMR&V seroprevalence. Logistic regression was used to identify factors associated with seropositivity. RESULTS: Among 804 university students, seroprevalence (positive or equivocal) for measles was 82.3% (95% CI 79.6-84.8%), mumps 79.5% (95% CI 76.7-82.3%), rubella 91.5% (95% CI 89.6-93.5%) and varicella 86.2% (95% CI 84.1-88.8%), with 452 (56.2%, 95% CI 52.8-59.6) seropositive to all four viruses. Varicella seropositivity was highest in the older birth cohort (born 1988-1991). Measles seropositivity was higher for international students compared to domestic students. Among international students, mumps seroprevalence was significantly lower than measles and rubella seroprevalence. International travel in the previous 12 months was reported by 63.1% of students, but only 18.2% of travellers reported seeking pre-travel health advice prior to most recent international travel. CONCLUSIONS: Overall, this study suggests immunity to MMR&V is sub-optimal. We found the university student population to be highly mobile and unlikely to seek pre-travel advice; thus, they are a potential source of infection importation. The implementation of university immunization policies could address the gaps identified and our findings can inform the development of targeted vaccination campaigns.

Universal masking during COVID-19 outbreaks in aged care settings: A systematic review and meta-analysis.

Aged care facilities (ACF) are a high-risk COVID-19 transmission setting, and older residents are at greater risk of severe outcomes. This systematic review and meta-analysis assessed whether universal masking and COVID-19 vaccination reduce SARS-CoV-2 attack rates (ARs) in ACF. Articles published between 1 December 2019 and 28 February 2022 were screened across five databases (Medline, Embase, PubMed, Scopus, Web of Science and Cumulative Index to Nursing and Allied Health Literature (CINAHL)). Risk of bias was assessed using relevant Joanna Briggs Institute critical appraisal tools. Meta-analysis of single proportions, subgroup analysis, and meta-regression were performed to compare the effects of universal masking and vaccine doses on pooled SARS-CoV-2 ARs. Of 99 included articles, SARS-CoV-2 ARs for residents were available in 86 studies (representing 139 outbreaks), and for staff in 49 studies (78 outbreaks). Universal masking was associated with lower SARS-CoV-2 ARs in ACF outbreaks (AR = 34.9% [95% CI: 27.2-42.6%]) compared to facilities without universal masking (67.3% [54.2-80.4%], p < .0001). In ACF with universal masking prior to outbreak onset, facility-wide testing, and documentation of asymptomatic infection, the asymptomatic AR at time of testing was 11.4% (6.5-17.4%) in residents. Receipt of zero, one and two vaccination doses were associated with ARs of 64.9% (49.6-80.2%), 54.9% (33.7-76.1%) and 45.2% (29.2-61.3%), respectively. To protect residents from COVID-19, ACF should provide vaccination of residents and staff, universal masking for staff, and facility-wide testing during times of heightened community transmission.

Population-Based Study of Pertussis Incidence and Risk Factors among Persons >50 Years of Age, Australia.

Despite vaccination programs, pertussis has been poorly controlled, especially among older adults in Australia. This longitudinal, retrospective, observational study aimed to estimate the incidence and risk factors of pertussis among persons ≥50 years of age in Australia in the primary care setting, including those with underlying chronic obstructive pulmonary disease (COPD) or asthma. We used the IQVIA general practitioner electronic medical record database to identify patients ≥50 years of age with a clinical diagnosis of pertussis during 2015-2019. Pertussis incidence rates ranged from 57.6 to 91.4 per 100,000 persons and were higher among women and highest in those 50-64 years of age. Patients with COPD or asthma had higher incidence rates and an increased risk for pertussis compared with the overall population ≥50 years of age. Our findings suggest that persons ≥50 years of age in Australia with COPD or asthma have a higher incidence of and risk for pertussis diagnosis.

Systematic review of influenza vaccine effectiveness against laboratory-confirmed influenza among older adults living in aged care facilities.

We estimated the effectiveness of influenza vaccines in preventing laboratory-confirmed influenza among older adults in aged care. Electronic database searches were conducted using search terms, and studies were selected as per the selection criteria. Fourteen studies were included for final review. The studies exhibited considerable variation in reported vaccine effectiveness (VE) across different seasons. Among the observational studies, VE ranged from 7.2% to 89.8% against laboratory-confirmed influenza across different vaccines. Randomized clinical trials demonstrated a 17% reduction in infection rates with the adjuvanted trivalent vaccine. The limitations include the small number of included studies conducted in different countries or regions, varied seasons, variations in diagnostic testing methods, a focus on the A/H3N2 strain, and few studies available on the effectiveness of enhanced influenza vaccines in aged care settings. Despite challenges associated with achieving optimal protection, the studies showed the benefits of influenza vaccination in the elderly residents.

Association of recent respiratory illness and influenza with acute myocardial infarction among the Bangladeshi population: A case-control study.

Current evidence suggests that recent acute respiratory infections and seasonal influenza may precipitate acute myocardial infarction (AMI). This study examined the potential link between recent clinical respiratory illness (CRI) and influenza, and AMI in Bangladesh. Conducted during the 2018 influenza season at a Dhaka tertiary-level cardiovascular (CV) hospital, it included 150 AMI cases and two control groups: 44 hospitalized cardiac patients without AMI and 90 healthy individuals. Participants were matched by gender and age groups. The study focused on self-reported CRI and laboratory-confirmed influenza ascertained via quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) within the preceding week, analyzed using multivariable logistic regression. Results showed that cases reported CRI, significantly more frequently than healthy controls (27.3% vs. 13.3%, adjusted odds ratio (aOR): 2.21; 95% confidence interval (CI): 1.05-4.06), although this was not significantly different from all controls (27.3% vs. 22.4%; aOR: 1.19; 95% CI: 0.65-2.18). Influenza rates were insignificantly higher among cases than controls. The study suggests that recent respiratory illnesses may precede AMI onset among Bangladeshi patients. Infection prevention and control practices, as well as the uptake of the influenza vaccine, may be advocated for patients at high risk of acute CV events.