The need for the mosaic framework
As we progress through the coronavirus disease 2019 (COVID-19) pandemic
towards an inter-pandemic period, countries are faced with the need to
sustainably transition their surveillance strategies to monitor
influenza, SARS-CoV-2, Respiratory Syncytial Virus (RSV) and other
respiratory viruses of epidemic and pandemic potential. Population
expansion, travel patterns, and global trade also present an ongoing
risk of new pandemics, and a continuing need to strengthen early warning
surveillance. To face these challenges countries must now increase the
number of effective surveillance approaches to address multiple
surveillance objectives, and extend partnerships for surveillance and
collaborative analyses of data across sectors. Doing so will improve
data for decision-making during interpandemic periods and to help ensure
that respiratory virus surveillance is both timely and scalable in
emergencies.
WHO Member States have requested a coordinated approach to the
sustainable monitoring of respiratory viruses of epidemic and pandemic
potential (1). For respiratory virus surveillance to function during
interpandemic periods, and to be resilient to inform decision-making
during times of emergency, surveillance systems must be well-suited to
the objectives that they are being implemented to address.
Fit-for-purpose surveillance will produce actionable and policy-relevant
information that will engender trust and demonstrate their value for
money, increasing commitment by public health authorities to invest in
surveillance over time. Conversely, poorly targeted, or inefficient
surveillance systems may generate sub-optimal or misleading data for
decision-making, and not be perceived as cost-effective to sustain or
scale in emergencies. Comprehensive surveillance for respiratory viruses
involves detecting and assessing emerging or re-emerging pathogens;
monitoring epidemiological and clinical characteristics of illness
associated with infections and the virological characteristics of
respiratory viruses currently in circulation; and informing the use of
human health interventions (Figure 1). As it is impossible to address
all these objectives with a single surveillance system, multiple systems
and complementary investigations (2) must work together to address the
many information needs of policy makers. In essence, each system or
study serves as a tile in a “mosaic”, and only when viewed together
will they provide the complete and understandable picture of the human
health risk and impact associated with epidemic and pandemic respiratory
viruses in circulation.