BACKGROUND Despite
public health efforts to reduce the global burden of
leprosy , gaps remain in the
knowledge surrounding
transmission of
infection .
Helminth co-infections have been associated with a shift towards the lepromatous end of the
disease spectrum, potentially increasing
transmission in co-endemic areas. OBJECTIVES Using this biologically plausible
association , we conducted a
geographic information systems (GIS) study to investigate the spatial
associations of
schistosomiasis and
leprosy in an endemic area of Minas Gerais (MG),
Brazil .
METHODS Data on new cases of
Mycobacterium leprae and
Schistosoma mansoni infections from 2007-2014 were retrieved from the Brazilian national notifiable
diseases information system for seven municipalities in and surrounding Vespasiano, MG. A total of 139 cases of
leprosy and 200 cases of
schistosomiasis were mapped to a municipality level. For one municipality, cases were mapped to a
neighborhood level and a stratified
analysis was conducted to identify spatial
associations . FINDINGS A
relative risk of 6.80 [95%
confidence interval (CI) 1.46 - 31.64] of
leprosy was found in
neighborhoods with
schistosomiasis .
Incidence rates of
leprosy increased with corresponding
incidence rates of
schistosomiasis , and the temporal
trends of both
infections were
similar . CONCLUSIONS The
associations found in this project support the hypothesis that
helminth infections may influence the
transmission of
leprosy in co-endemic areas.