Ecoepidemics with a nonlinear disease incidence

We present two new models for interacting populations subject to a transmissible disease. The novelty lies in the assumption that herd behavior influences the disease incidence, rather than the demographic description of the interactions, as in previous related similar models. As it is already known from other ecoepidemiological situations, the epidemics may affect the system demographic outcomes

On the spreading of communicable diseases in farming environments

Epidemiological models for disease propagation, developed in strict collaboration with veterinarians, are important for providing farmers with guidelines on how to fight diseases that spread by contact among animals. Directing our attention on hog-raising farms at first, we consider some control issues for containing the Aujeszky disease propagation. This is of high interest in a specific Piedmontese area, where in the farms occupying an area of 30 square kilometers, about 90,000 hogs are concentrated. A particularly strong and counterintuitive result for disease eradication is obtained in the second case of interest, concentrating on CAEV (Caprine Arthritis Encephalitis Virus), a goats-affecting disease.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Departamento de Biología Celular, Genética y Fisiologí

Viral epidemiology of the adult Apis Mellifera infested by the Varroa destructor mite

The ectoparasitic mite Varroa destructor has become one of the major worldwide threats for apiculture. Varroa destructor attacks the honey bee Apis mellifera weakening its host by sucking hemolymph. However, the damage to bee colonies is not strictly related to the parasitic action of the mite but it derives, above all, from its action as vector increasing the trasmission of many viral diseases such as acute paralysis (ABPV) and deformed wing viruses (DWV), that are considered among the main causes of CCD (Colony Collapse Disorder). In this work we discuss an SI model that describes how the presence of the mite affects the epidemiology of these viruses on adult bees. We characterize the system behavior, establishing that ultimately either only healthy bees survive, or the disease becomes endemic and mites are wiped out. Another dangerous alternative is the Varroa invasion scenario with the extinction of healthy bees. The final possible configuration is the coexistence equilibrium in which honey bees share their infected hive with mites. The analysis is in line with some observed facts in natural honey bee colonies. Namely, these diseases are endemic. Further, if the mite population is present, necessarily the viral infection occurs. The findings of this study indicate that a low horizontal transmission rate of the virus among honey bees in beehives will help in protecting bee colonies from Varroa infestation and viral epidemics

A model for an aquatic ecosystem

An ecosystem made of nutrients, plants, detritus and dissolved oxygen is presented. Its equilibria are established. Sufficient conditions for the existence of the coexistence equilibrium are derived and its feasibility is discussed in every detail