What are the phases in a pandemic that WHO has developed to prepare and plan for management?

The World Health Organization (WHO) has developed a pandemic phases framework to prepare and plan for the management of pandemics. The framework includes six phases:

1. Investigation Phase

- Potential introduction of a new disease

- Confirmation of sustained human-to-human transmission outside the outbreak area

- Risk assessment and development of preparedness plans

2. Alert Phase

- Increase in sustained transmission

- Significant spread within the community

- Activation of pandemic preparedness plans

3. Pandemic Preparedness Phase

- Localized transmission in multiple countries or regions

- Intensified surveillance and containment measures

- Preparation of health systems for potential widespread transmission

4. Pandemic Spread Phase

- Widespread transmission in multiple regions or countries on different continents

- Implementation of large-scale containment measures

- Significant public health impact and global disruption

5. Pandemic Sustained Transmission Phase

- Ongoing persistent transmission in various regions

- Circulation of virus in a significant proportion of the population

- Adaptation to the pandemic through vaccination, public health measures, and social interventions

6. Post-Pandemic Transition Phase

- Reduced transmission and incidence of cases

- Transition from emergency response to long-term management

- Development of vaccines, treatments, and surveillance systems to mitigate future risks

The WHO uses this framework to guide international public health responses to pandemics, promoting coordination, collaboration, and effective planning among member states and partners.