Insights into the epidemiological link between biting flies and pemphigus foliaceus in southeastern Brazil

• Published in: Acta tropica 2017-12, Vol.176, p.455-462
• Main Authors: Vernal, Sebastian, Pepinelli, Mateus, Casanova, Claudio, Goulart, Thais M., Kim, Olivia, De Paula, Natalia A., Pinto, Mara C., Sá-Nunes, Anderson, Roselino, Ana Maria
• Format: Article
• Language: English
• Subjects: Adult; Animals; Black flies; Brazil - epidemiology; Case-Control Studies; Desmoglein 1 - immunology; Enzyme-Linked Immunosorbent Assay; Female; Geographic Mapping; Humans; Immunoglobulin G - blood; Insect Bites and Stings - epidemiology; Insect Bites and Stings - immunology; Male; Middle Aged; Pemphigus - epidemiology; Pemphigus - immunology; Pemphigus foliaceus; Phlebotomine; Prevalence; Psychodidae - immunology; Salivary Glands - immunology; Sandflies; Simuliidae; Simuliidae - immunology; Tissue Extracts - immunology
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2017.09.015

[Display omitted] •Biting flies and Pemphigus Foliaceus (PF) showed coincidental spatial distribution.•The exposure of PF patients to salivary proteins from biting flies was confirmed.•Anti–flies’ salivary proteins correlated with anti–Desmoglein 1 in PF patients.•A link between S. nigrimanum and N. neivai bites, and PF pathogenesis is proposed. Black fly and sandfly bites are related to the endemicity of pemphigus foliaceus (PF); however, an immune reaction against the salivary proteins from these flies still requires confirmation in the case of PF patients living in southeastern Brazil. To georeference the distribution of Simuliidae (Diptera: Simuliidae) and Phlebotominae (Diptera: Psychodidae) and of PF cases in the northeastern region of São Paulo State, and to assess the humoral immune response against salivary gland extracts (SGEs) from biting flies in PF patients, relatives, and neighbours. PF patients’ medical information recorded between 1965 and 2014 were obtained from the database of the University Hospital. Data on the distribution of fly species were collected from scientific reports and epidemiological databases. Spatial maps relating the distribution of biting flies with PF cases were plotted. Serum IgG antibodies against the SGEs from Simulium nigrimanum, Nyssomyia neivai, and Aedes aegypti (as control) were determined by ELISA. Two hundred and eighty-five PF cases were distributed in 60 municipalities with a prevalence of 57.5 per million inhabitants, revealing well-defined geographical clusters. S. nigrimanum and N. neivai specimens were registered in eight (13.3%) and 26 (43.3%) of these municipalities, respectively. PF patients, and their relatives presented higher levels of IgG against the SGEs of S. nigrimanum and N. neivai (P