Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Epidemic outbreaks in complex heterogeneous networks   We present a detailed analytical and numerical study for the spreading of
infections in complex population networks with acquired immunity. We show that
the large connectivity fluctuations usually found in these networks strengthen
considerably the incidence of epidemic outbreaks. Scale-free networks, which
are characterized by diverging connectivity fluctuations, exhibit the lack of
an epidemic threshold and always show a finite fraction of infected
individuals. This particular weakness, observed also in models without
immunity, defines a new epidemiological framework characterized by a highly
heterogeneous response of the system to the introduction of infected
individuals with different connectivity. The understanding of epidemics in
complex networks might deliver new insights in the spread of information and
diseases in biological and technological networks that often appear to be
characterized by complex heterogeneous architectures.

25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom