How landscape structure affects the risk of hantavirus transmission in the Cerrado and Atlantic Forest of São Paulo State, Brazil

• Grant number: 14/18878-5
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): February 01, 2015
• Effective date (End): June 30, 2015
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Jean Paul Walter Metzger
• Grantee: Paula Ribeiro Prist
• Supervisor: Maria Uriarte
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Research place: Columbia University in the City of New York, United States
• Associated to the scholarship: 13/12515-5 - How landscape structure influences hantaviruses transmission in São Paulo State, Brazil, BP.DR

Abstract

Hantavirus Pulmonary Syndrome is a disease caused by Hantavirus, a collection of negative sense RNA viruses in the Bunyaviridae family that are highly virulent to humans. Rodents serve as the principal reservoir host species, but exhibit pronounced variation in their abilities to serve as reservoirs. These species, in Brazil, are habitat generalist, and increase in abundance and become more virulent in human dominated landscapes increasing the risk of transmission to humans. This may occur because anthropogenic alterations to landscape structure typically alter landscape structure, with implications for rodent community structure, and therefore the population density of reservoir host. Habitat composition (i.e. the proportion of introduced and native habitat) and configuration (i.e. amount of edge at the landscape) influences rodent community structure (i.e. fragmented habitats leads to the loss of specialist species and the impoverishment of the small mammal community, what leads to the increase of population density of some generalist species, including the hantavirus reservoir species). In Brazil no specific studies of landscape structure, fragmentation and transmission of hantavirus have been found, but studies conducted in tropical forest (Suzan etal.2008a, b, 2009 in Panama; Goodin et al.2006 in Paraguay), indicate that there should be a positive effect of habitat loss, fragmentation and landscape composition in the transmission of hantaviruses. However, more specific studies verifying these effects are necessary for a better understanding of how landscape structure can lead to increased transmission of the virus in Brazil. Therefore this study aims to (i) quantify how three key components of landscape structure (i.e. habitat composition, configuration, and border) influence the transmission of Hantavirus in São Paulo State, Brazil and (ii) to create a hantavirus risk map for São Paulo state; (iii) to explore how climate change may influence the disease transmission risk and; (iv) to explore how different forest restoration scenarios may influence the disease transmission risk. To do this, we will use Bayesian hierarchical spatial models that include climatic variables, landscape structure metrics and habitat suitability of rodent reservoir species, predicted by niche modeling. We believe that areas with less forest cover, a large number of fragments and a large amount of edge, also have more disease cases. For the predictive scenarios, we believe that if the climate change scenario show an increase in the amount of precipitation, will also cause an increase in HPS risk, at the same time, we believe that restoration scenarios that improve forest cover and connectivity, diminishing the amount of fragments and edge density will cause a decrease in HPS risk. Through these studies we aim to better understand how human activities are altering and modulating the transmission of infectious diseases to humans, and inform preventive measures aimed to reduce mortality from hantavirus infection. (AU)