Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamics of epidemic diseases without guaranteed immunity   The global SARS-CoV-2 pandemic suggests a novel type of disease spread
dynamics. WHO states that there is currently no evidence that people who have
recovered from COVID-19 and have antibodies are immune from a second infection
[WHO]. Conventional mathematical models consider cases for which a recovered
individual either becomes susceptible again or develops an immunity. Here, we
study the case where infected agents recover and only develop immunity if they
are continuously infected for some time. Otherwise, they become susceptible
again. We show that field theory bounds the peak of the infectious rate.
Consequently, the theory's phases characterise the disease dynamics: (i) a
pandemic phase and (ii) a response regime. The model excellently describes the
epidemic spread of the SARS-CoV-2 outbreak in the city of Wuhan, China. We find
that only 30% of the recovered agents have developed an immunity. We anticipate
our paper to influence the decision making upon balancing the economic impact
and the pandemic impact on society. As long as disease controlling measures
keep the disease dynamics in the "response regime", a pandemic escalation
('second wave') is ruled out.

30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat