Investigator(s)
| Submitter |
Tshering Dorji Royal Centre for Disease Control Tshering Dorji 
|
| Principal Investigator |
Tshering Dorji Royal Centre for Disease Control Tshering Dorji
|
| Co-Investigator(s) |
Sonam Gyeltshen Royal Centre for Disease Control Sonam Gyeltshen
|
| Co-Investigator(s) |
Kunzang Dorji RCDC Kunzang Dorji
|
| Co-Investigator(s) |
Vishal Chhettri RCDC/RMIT University Vishal Chhettri
|
| Co-Investigator(s) |
Holly Sadler WHO Holly Sadler
|
Title(s) and abstract
| Scientific title | Assessment of Influenza Severity in Bhutan Using the WHO Pandemic Influenza Severity Assessment (PISA) Framework: A Retrospective Implementation Research |
| Public title | Assessment of Influenza Severity in Bhutan Using the WHO Pandemic Influenza Severity Assessment (PISA) Framework: A Retrospective Implementation Research |
| Background | Historically, influenza has caused four global pandemics in 1918 (H1N1), 1957 (H2N2), 1968 (H3N2), and 2009 (H1N1). The virus’s constant genetic changes pose a continual threat of novel strains. The 2009 H1N1 pandemic revealed significant gaps in preparedness, prompting advancements in surveillance, focused research, and risk assessment tools. Consequently, to address gaps in influenza surveillance, the 2011 World Health Assembly recommended developing severity assessment measures for influenza epidemics, leading to the adoption of the Pandemic Influenza Severity Assessment (PISA) framework. This framework evaluates influenza severity by integrating measures of transmissibility, disease seriousness, and healthcare impact, based on historical data, facilitating comparisons during both epidemic and pandemic periods. A Technical Working Group (TWG) reviewed PISA's performance during COVID-19, exploring parameter choices and threshold-setting differences between influenza and SARS-CoV-2. In 2024, the revised PISA framework was published, allowing for continuous assessment of influenza and syndromic respiratory illness activity relative to historical data. Bhutan has adopted the PISA framework as part of its national surveillance strategy since January 2024, yet a thorough retrospective assessment of influenza severity using this framework has not been conducted. This study aims to retrospectively apply the PISA framework to influenza surveillance data from Bhutan to establish baseline and threshold values for influenza activity, thereby strengthening the country's preparedness for both seasonal and pandemic influenza and assess the severity of past influenza seasons. |
| Objectives | The primary objective of this retrospective study is to assess influenza severity in Bhutan using the PISA framework. Specific objectives include: 1. Establish national influenza baselines and thresholds; To establish baseline levels and thresholds for influenza activity in Bhutan using historical data, providing a reference point for assessing future influenza seasons. 2. Evaluate and analyse influenza activity for past seasons: To assess the patterns of influenza activity for the past influenza seasons in Bhutan by analysing surveillance data to identify key seasonal peaks and trends. |
| Study Methods | Study Design, Study Setting and Study Population: This is a retrospective observational study utilizing secondary data analysis to assess influenza severity in Bhutan using the WHO Pandemic Influenza Severity Assessment (PISA) framework. The study will be a nation-wide study using the surveillance data collected through the National Early Warning Alert and Response Surveillance (NEWARS) and the COVID-19 Integrated Influenza Surveillance systems by the Royal Centre for Disease Control (RCDC). The weekly ARI cases are reported nation-wide on NEWARS, while the Influenza-Like Illness (ILI) and Severe Acute Respiratory Illness (SARI) cover geographically distributed sentinel sites in the country. The data in this study will include only aggregated and de-identified information and no individual-level patient data will be used or extracted from the surveillance systems. Dataset Inclusion Criteria: Surveillance data from 2016 to 2019 and 2023 will be included in the study. These years represent a stable period in Bhutan’s influenza surveillance system, with consistent data reporting, making them suitable for establishing reliable baselines and severity thresholds. The years 2020-2022, affected by the COVID-19 pandemic, are excluded due to disruptions in routine influenza transmission and surveillance activities. Parameter Selection and Study Variables: For this study, we will extract influenza specific data from COVID-19 integreted influenza surveillance system and NEWARIS system for the study period. Influenza activity will be assessed based on updated WHO PISA guideline. To set thresholds for transmissibility and morbidity and mortality, WHO ACM will be utilized. |
| Expected outcomes and use of results | Expected outcome includes: Improving public health preparedness: Establishing specific thresholds for epidemic, moderate, high, and extraordinary levels of influenza severity will provide Bhutanese health authorities with a standardized approach to assess and respond to influenza outbreaks. This framework will significantly enhance decision-making processes in public health. Localized influenza analysis: Bhutan’s unique geographic and climatic conditions, with semi-annual peaks in influenza activity, necessitate a tailored approach to assessing influenza severity. Applying the PISA framework in this context will allow for a more accurate evaluation of influenza transmissibility and morbidity, which can be compared to global trends. Informing pandemic preparedness: Lessons learned from the COVID-19 pandemic have demonstrated the importance of robust surveillance and data-driven response mechanisms. By analysing historical data, this study will provide insights that can inform Bhutan’s broader pandemic preparedness strategies, particularly for respiratory viruses. |
| Keywords | Pandemic Influenza Severity Assessment (PISA), Influenza, Bhutan |
Research Details
| Student research | No |
| Start Date | 01-Dec-2024 |
| End Date | 31-May-2025 |
| Key Implementing Institution | Royal Centre for Disease Control |
| Multi-country research | No |
| Nationwide research | Yes |
| Research Domain(s) | Communicable Disease Research |
| Research field(s) | Infectious Disease |
| Involves human subjects | Yes |
| Other (Retrospective observational study) | |
| Data Collection | Secondary data |
| Proposal reviewed by other Committee | No |