Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An epidemiological model of viral infections in a Varroa-infested bee
  colony: the case of a bee-dependent mite population size   In recent years the spread of the ectoparasitic mite Varroa destructor has
become the most serious threat to worldwide apiculture. In the model presented
here we extend the bee population dynamics with mite viral epidemiology
examined in an earlier paper by allowing a bee-dependent mite population size.
The results of the analysis match field observations well and give a clear
explanation of how Varroa affects the epidemiology of certain naturally
occurring bee viruses, causing considerable damages to colonies. The model
allows only four possible stable equilibria, using known field parameters. The
first one contains only the thriving healthy bees. Here the disease is
eradicated and also the mites are wiped out. Alternatively, we find the
equilibrium still with no mite population, but with endemic disease among the
thriving bee population. Thirdly, infected bees coexist with the mites in the
Varroa invasion scenario; in this situation the disease invades the hive,
driving the healthy bees to extinction and therefore affecting all the bees.
Coexistence is also possible, with both populations of bees and mites thriving
and with the disease endemically affecting both species. The analysis is in
line with field observations in natural honey bee colonies. Namely, these
diseases are endemic and if the mite population is present, necessarily the
viral infection occurs. Further, in agreement with the fact that the presence
of Varroa increments the viral transmission, the whole bee population may
become infected when the disease vector is present in the beehive. Also, a low
horizontal transmission rate of the virus among the honey bees will help in
protecting the bee colonies from Varroa infestation and viral epidemics.

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The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg