patients. The activities described in this lot and in this tender will follow those of the established contracts. 

The contractor is expected to perform the activities in close collaboration with ECDC, taking into account the joint work performed by ECDC and WHO, as well as work performed by other stakeholders, such as the EMA and the European Commission on these topics. 

The ECDC Hospital network will therefore represent the infrastructure with the objectives to: 

• Conduct European level SARI surveillance 

• Conduct vaccine effectiveness studies for COVID-19 and seasonal influenza 

• Conduct studies to evaluate the impact of pharmaceutical and not pharmaceutical interventions, including that of vaccination programmes 

• Conduct studies to describe the burden of disease of severe acute respiratory infections, including a description of the respiratory pathogens associated with SARI disease and the epidemiological characteristics of SARI cases as well risk factors associated with SARI disease and severe outcome 

• Represent the infrastructure and establish a ECDC Hospital network for integrated surveillance of severe infectious diseases to better understand and be able to prevent relevant risks 

A study site in this lot can be represented by a region or country that receives data from one or more units (i.e. hospitals). A study site is typically represented by national or regional public health institute. 

Ideally all study sites should contribute to meet all the objectives presented, however it is foreseen that in some $_{sites}$ some objectives might not be reachable. Decisions on how to ensure highest representation in the respect to the objectives and a fair geographical representation will be taken in agreement with ECDC. 

The activities described in this lot should be performed in collaboration with the national competent public authority of the concerned EU Member States; the ECDC will facilitate these interactions if needed. 

## 2.2.2 Place of performance and number of meetings of LOT 1 

All tasks are expected to be performed at the contractor’s premises and on the study sites. It is estimated that only two meetings (see table with deliverables) could be held either at ECDC or in a location in EU/EEA or Western Balkans. 

## 2.2.3 Summary table of tasks, deliverables, quality requirements and timelines in LOT 1 

See the Table Lot 1 / Technical annex A describing the tasks and the related deliverables envisaged under the lot during the duration of the framework contract (FWC) including estimated timelines and quality requirements. 

## 2.3 Description of the services LOT 2: Assessment of COVID-19 vaccine effectiveness among healthcare workers 

## 2.3.1 Scope of the services in LOT 2 

The objective of this lot is to assess vaccine effectiveness against multiple COVID-19-related health outcomes among healthcare workers from different study sites across EU/EEA Member States. 

The study site in this lot is be defined as a hospital providing assistance on the basis of urgent/intermediate care. 

