Search

Highlights: [•] This study adds to the limited research on VE to influenza from the southern hemisphere. [•] TIV vaccines show low to moderate protection against influenza positive hospitalisation in 2012. [•] VE varied by influenza type and subtype. [•] Vaccination appeared to be less effective in patients aged 65 years and older. [•] Older people did not appear to be significantly protected against infection with influenza A (H3N2). [ABSTRACT FROM AUTHOR]

Background: Understanding immunity, incidence and risk factors of the 2009 influenza A(H1N1) pandemic (2009 H1N1) through a national seroprevalence study is necessary for informing public health interventions and disease modelling. Methods and Findings: We collected 1687 serum samples and individual risk factor data between November-2009 to March-2010, three months after the end of the 2009 H1N1 wave in New Zealand. Participants were randomly sampled from selected general practices countrywide and hospitals in the Auckland region. Baseline immunity was measured from 521 sera collected during 2004 to April-2009. Haemagglutination inhibition (HI) antibody titres of ≥1:40 against 2009 H1N1 were considered seroprotective as well as seropositive. The overall community seroprevalence was 26.7% (CI:22.6-29.4). The seroprevalence varied across age and ethnicity. Children aged 5-19 years had the highest seroprevalence (46.7%;CI:38.3- 55.0), a significant increase from the baseline (14%;CI:7.2-20.8). Older adults aged ≥60 had no significant difference in seroprevalence between the serosurvey (24.8%;CI:18.7-30.9) and baseline (22.6%;CI:15.3-30.0). Pacific peoples had the highest seroprevalence (49.5%;CI:35.1-64.0). There was no significant difference in seroprevalence between both primary (29.6%;CI:22.6-36.5) and secondary healthcare workers (25.3%;CI:20.8-29.8) and community participants. No significant regional variation was observed. Multivariate analysis indicated age as the most important risk factor followed by ethnicity. Previous seasonal influenza vaccination was associated with higher HI titres. Approximately 45.2% of seropositive individuals reported no symptoms. Conclusions: Based on age and ethnicity standardisation to the New Zealand Population, about 29.5% of New Zealanders had antibody titers at a level consistent with immunity to 2009 H1N1. Around 18.3% of New Zealanders were infected with the virus during the first wave including about one child in every three. Older people were protected due to pre-existing immunity. Age was the most important factor associated with infection followed by ethnicity. Healthcare workers did not appear to have an increased risk of infection compared with the general population. [ABSTRACT FROM AUTHOR]

Background: Many countries around the world have adopted social distancing as one of the public health measures to reduce COVID-19 transmissions in the community. Such measures could have negative effects on the mental health of the population. The aims of this study are to (1) track the impact of COVID-19 on self-reported mood, self-rated health, other health and psychosocial indicators, and health services utilization of people who have an interRAI assessment during the first year of COVID-19; (2) compare these indicators with the same indicators in people who had an interRAI assessment in the year before COVID-19; and (3) report these indicators publicly as soon as data analysis is completed every 3 months.Methods: interRAI COVID-19 Study (iCoS) is an observational study on routinely collected national data using the interRAI Home Care and Contact Assessment, which are standardized geriatric assessment tools mandated for all people assessed for publicly funded home support services and aged residential care in New Zealand. Based on the 2018/19 figures, we estimated there are 36,000 interRAI assessments per annum. We will compare the four post-lockdown quarters (from 25th March 2020) with the respective pre-lockdown quarters. The primary outcomes are self-reported mood (feeling sad, depressed or hopeless: 0 = no, 1 = yes) and self-rated health (0 = excellent, 1 = good, 2 = fair, 3 = poor). We will also analyze sociodemographics, other secondary health and psychosocial indicators, and health services utilization. Descriptive statistics will be conducted for primary outcomes and other indicators for each of the eight quarters. We will compare the quarters using regression models adjusted for demographic characteristics using weights or additional variables. Key health and psychosocial indicators will be reported publicly as soon as data analysis is completed for each quarter in the 12-month post-lockdown period by using a data visualization tool.Discussion: This rapid translation of routinely collected national interRAI data will provide a means to monitor the health and psychosocial well-being of vulnerable older New Zealanders. Insights from this study can be shared with other countries that use interRAI and prepare health and social services for similar epidemics/pandemics in the future. [ABSTRACT FROM AUTHOR]

Background: Understanding the attack rate of influenza infection and the proportion who become ill by risk group is key to implementing prevention measures. While population-based studies of antihemagglutinin antibody responses have been described previously, studies examining both antihemagglutinin and antineuraminidase antibodies are lacking.Methods: In 2015, we conducted a seroepidemiologic cohort study of individuals randomly selected from a population in New Zealand. We tested paired sera for hemagglutination inhibition (HAI) or neuraminidase inhibition (NAI) titers for seroconversion. We followed participants weekly and performed influenza polymerase chain reaction (PCR) for those reporting influenza-like illness (ILI).Results: Influenza infection (either HAI or NAI seroconversion) was found in 321 (35% [95% confidence interval, 32%-38%]) of 911 unvaccinated participants, of whom 100 (31%) seroconverted to NAI alone. Young children and Pacific peoples experienced the highest influenza infection attack rates, but overall only a quarter of all infected reported influenza PCR-confirmed ILI, and one-quarter of these sought medical attention. Seroconversion to NAI alone was higher among children aged <5 years vs those aged ≥5 years (14% vs 4%; P < .001) and among those with influenza B vs A(H3N2) virus infections (7% vs 0.3%; P < .001).Conclusions: Measurement of antineuraminidase antibodies in addition to antihemagglutinin antibodies may be important in capturing the true influenza infection rates. [ABSTRACT FROM AUTHOR]

Background We aimed to estimate the protection afforded by inactivated influenza vaccine, in both community and hospital settings, in a well characterised urban population in Auckland during 2014. Methods We used two different comparison groups, all patients who tested negative for influenza and only those patients who tested negative for influenza and had a non-influenza respiratory virus detected, to calculate the vaccine effectiveness in a test negative study design. Estimates were made separately for general practice outpatient consultations and hospitalised patients, stratified by age group and by influenza type and subtype. Vaccine status was confirmed by electronic record for general practice patients and all respiratory viruses were detected by real time polymerase chain reaction. Results 1039 hospitalised and 1154 general practice outpatient consultations met all the study inclusion criteria and had a respiratory sample tested for influenza and other respiratory viruses. Compared to general practice patients, hospitalised patients were more likely to be very young or very old, to be Māori or Pacific Islander, to have a low income and to suffer from chronic disease. Vaccine effectiveness (VE) adjusted for age and other participant characteristics using all influenza negative controls was 42% (95% CI: 16 to 60%) for hospitalised and 56% (95% CI: 35 to 70%) for general practice patients. The vaccine appeared to be most effective against the influenza A(H1N1)pdm09 strain with an adjusted VE of 62% (95% CI:38 to 77%) for hospitalised and 59% (95% CI:36 to 74%) for general practice patients, using influenza virus negative controls. Similar results found when patients testing positive for a non-influenza respiratory virus were used as the control group. Conclusion This study contributes to validation of the test negative design and confirms that inactivated influenza vaccines continue to provide modest but significant protection against laboratory-confirmed influenza. [ABSTRACT FROM AUTHOR]

Highlights: [•] The effect of simple virus enrichment methods were tested on a metagenomics dataset. [•] Centrifugation, filtration or nuclease-treatment was evaluated. [•] A multi-step enrichment method increased the proportion of virus sequences. [•] This evaluation guides researchers in their choice of enrichment methodology. [ABSTRACT FROM AUTHOR]