Transmission dynamics and control of Sporotrichosis in domestic felines

Sporotrichosis is a subcutaneous mycosis with a global distribution, also known as "rose gardeners disease". Brazil is experiencing a rapid spread of the zoonotic transmission of of Sporothrix brasiliensis, the main etiological agent of this disease in this country, affecting domestic felines. Cost-effective interventions need to be developed to control this emergent public health problem. To allow for the comparison of alternative control strategies, we propose in this paper, a mathematical model representing the transmission of S. brasiliensis among cats, stratified by age and sex. Analytical properties of the model are derived and simulations show possible strategies for reducing the endemic levels of the disease in the cat population, with a positive impact on human health. The scenarios included mass treatment of infected cats and mass implementation of contact reduction practices, such as neutering. The results indicate that mass treatment can reduce substantially the disease prevalence, and this effect is potentialized when combined with neutering or other contact-reduction interventions. On the other hand, contact-reduction methods alone are not sufficient to reduce prevalence. Author summarySporotrichosis, as a neglected tropical mycosis, has in domestic cats a very important reservoir for Sporothrix sp., its pathogen. Infected cats can easily transmit the fungus to other cats and also to humans by means of scratching and biting. Here we propose a mathematical model incorporating all forms of transmission of Sporothrix within a cat population, taking into account age and sex-related behavioral differences which can affect the transmission dynamics. The model also includes a treated compartment, which facilitates the exploration of pharmacological interventions to reduce the prevalence of the disease. We derive the next-generation matrix for the model, which allows the calculation of the diseases basic reproduction number under different scenarios. Using the model, we explore different control scenarios involving treatment of the disease, but also the contribution of neutering of cats to the reduction of transmission through changes induced by neutering, of the cats social interactions.