Pandemic (H1N1) 2009 risk for frontline health care workers

Risk of SARS-CoV-2 infection in dental healthcare workers - a systematic review and meta-analysis

Background

Mounting evidence supports an association between the use of personal protective equipment (PPE) and the risk of infection from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in dental healthcare workers (DCW). However, the prevalence and incidence of SARS-CoV-2 infections in the setting of dental care remains poorly characterized.

Methods

A systematic review and meta-analysis of studies published prior to Mai 2023 providing epidemiological data for the occurrence of SARS-CoV-2 in DCW was performed. A random-effects model was used to calculate pooled estimates and odds ratios (ORs) with corresponding 95% confidence intervals (CIs). The associated factors were narratively evaluated. Risk of bias was assessed using the Joanna Briggs Institute tool for prevalence studies.

Results

Twenty-nine eligible studies were identified including a total of 85,274 DCW at risk; 27 studies met the criteria for the meta-analysis. Among the included DCW, the overall prevalence of SARS-CoV-2 was 11.8% (13,155/85,274; 95%CI, 7.5%-17%), whereby the degree of heterogeneity between the studies was considerable (I2=99.7%). The pooled prevalence rate for dentists and dental hygienists alone was 12.7% (1943/20,860; 95%CI, 8.0%-18.0%), showing significantly increased odds of contracting a SARS-CoV-2 infection compared to dental assistant personnel, the prevalence rate for which was less than half, at 5.2% (613/15,066; OR=2.42; 95% CI, 2.2-2.7). In the subgroup of 17 studies from countries with high income there was a significantly lower prevalence rate of 7.3% (95% CI, 5%-10%) in DCW compared to the prevalence rate in low- and middle-income countries, which came to 20.8% (95% CI, 14%-29%; p<0.001). In 19 out of the 29 studies (65.5%), specific information on the use of and adherence to PPE was absent while in the reports with concrete figures the wearing of N95 (or at least surgical masks) by DCW appeared to be associated with lower SARS-CoV-2 prevalence rates.

Conclusions

DCW were, depending in each case on their proximity to patients, at particular risk of SARS-CoV-2 infection during the COVID-19 pandemic. Until a significant level of vaccination protection against newer SARS-CoV-2 variants can be built up in the population, dental healthcare facilities should further maintain their focus on using PPE according to current guidelines.

New Zealand nurses perceptions of caring for patients with influenza A (H1N1)

AIM

This study aimed to explore the perceptions of the highly specialized nurses who provided extracorporeal membrane oxygenation therapy for the mostly young and critically ill patients during the 2009 H1N1 pandemic.

BACKGROUND

The 2009 influenza A (H1N1) virus caused a global pandemic and also affected New Zealand during that winter. Nine H1N1-infected adult patients with severe acute respiratory distress syndrome were admitted into an intensive care unit of a large urban hospital for rescue extracorporeal membrane oxygenation therapy.

DESIGN

The study used a two-phase mix methods study design.

METHODS

Phase 1 of the study involved five nurses attending a focus group interview to collect their views of the challenges and issues of caring for these patients. The results of the focus group were used to formulate the phase 2 survey. In total, 25 eligible nurses were invited to complete an anonymous survey; 18 completed and returned surveys giving a 72% response rate.

RESULTS

The survey identified issues including the acuity and high mortality rate of those affected, nurses working in an isolated environment because of infection control requirements, limited support and being asked to work extra shifts.

CONCLUSION

Despite these challenges, the nurses felt positive about their experience of caring for the H1N1 patients, and felt the experience advanced their skills and improved job satisfaction.

RELEVANCE TO CLINICAL PRACTICE

For future pandemics, this study identified the need for all staff to have a basic understanding of extracorporeal membrane oxygenation; strengthen inter-professional collaboration and communication; provision for more support and recognition of these highly specialized nurses, along with providing regular pandemic updates and offering counselling services.

Risk factors and effectiveness of preventive measures against influenza in the community

Please cite this paper as: Castilla et al. (2013) Risk factors and effectiveness of preventive measures against influenza in the community. Influenza and Other Respiratory Viruses 7(2) 177–183.

Background  The role of different risk exposures and preventive measures against influenza has not been well established.

Objective  The aim of this study was to evaluate risk factors and measures to prevent influenza infection in the community.

Methods  We conducted a multicenter case–control study. Cases were 481 outpatients aged 18 years or older with laboratory‐confirmed influenza A(H1N1)09 in the 2009–2010 season in Spain. A control was selected for each case from outpatients from the same area matched by age and date of consultation. Information on risk situations, preventive measures and other variables was obtained by interview and review of the medical record.

Results  In the multivariate conditional logistic regression analysis, the risk of a diagnosis of influenza increased with the number of cohabitants (compared with <3 cohabitants, three cohabitants had an OR = 1·80, 95% CI 1·12–2·89, and ≥5 cohabitants had an OR = 2·66, 95% CI 1·31–5·41) and for health care workers (OR = 2·94, 95% CI 1·53–5·66). The use of metropolitan public transport was associated with a lower frequency of a diagnosis of influenza (OR = 0·45, 95% CI 0·30–0·68) but not the use of taxis or long‐distance transport. The influenza A(H1N1)09 vaccine had a protective effect (OR = 0·13, 95% CI 0·04–0·48), unlike hand washing after touching contaminated surfaces or the use of alcohol‐based hand sanitizers.

Conclusion  The home environment appears to play an important role in the spread of influenza in adults, but not the use of public transport. Health care workers have a higher risk of contracting influenza. Vaccination was the most effective preventive measure.

No association between mannose-binding lectin deficiency and H1N1 2009 infection observed during the first season of this novel pandemic influenza virus

Genetic variations in host immunity may influence susceptibility to novel infections like the recently emergent pandemic influenza virus. Prior studies demonstrated that mannose-binding lectin (MBL) inactivates influenza. Furthermore, MBL deficiency is common and appears to predispose to respiratory virus infections. Therefore, we studied whether MBL deficiency played a role in infection with the novel H1N1 2009 influenza strain in exposed health care workers. In a nested case-control study, we observed no association between phenotypic MBL deficiency, variously defined, and predisposition to H1N1 2009 influenza in 63 pairs of seropositive and seronegative participants. MBL appears to currently have little impact on innate immune responses to H1N1 2009 influenza.