Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Estimating Hidden Asymptomatics, Herd Immunity Threshold and Lockdown
  Effects using a COVID-19 Specific Model   A quantitative COVID-19 model that incorporates hidden asymptomatic patients
is developed, and an analytic solution in parametric form is given. The model
incorporates the impact of lockdown and resulting spatial migration of
population due to announcement of lockdown. A method is presented for
estimating the model parameters from real-world data. It is shown that increase
of infections slows down and herd immunity is achieved when symptomatic
patients are 4-6\% of the population for the European countries we studied,
when the total infected fraction is between 50-56 \%. Finally, a method for
estimating the number of asymptomatic patients, who have been the key hidden
link in the spread of the infections, is presented.

2
The categories of this paper are: math
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat