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

Author(s)

Vernal, Sebastian ^[1] ; Pepinelli, Mateus ^{[2, 3]} ; Casanova, Claudio ^[4] ; Goulart, Thais M. ^[5] ; Kim, Olivia ^[1] ; De Paula, Natalia A. ^[1] ; Pinto, Mara C. ^[6] ; Sa-Nunes, Anderson ^[7] ; Roselino, Ana Maria ^[1]

Affiliation

^[1] Univ Sao Paulo, Ribeirao Preto Med Sch, Div Dermatol, Dept Clin Med, Ribeirao Preto, SP - Brazil

^[2] Univ Toronto, Dept Ecol & Evolutionary Biol, Toronto, ON - Canada

^[3] Royal Ontario Museum, Dept Nat Hist, Toronto, ON - Canada

^[4] Hlth Secretariat Sao Paulo State, Superintendence Endem Dis Control, Mogi Guacu, SP - Brazil

^[5] Univ Estadual Campinas, Inst Biol, Dept Anim Biol, Campinas, SP - Brazil

^[6] Sao Paulo State Univ Julio Mesquita Filho, Dept Parasitol, Araraquara, SP - Brazil

^[7] Univ Sao Paulo, Inst Biomed Sci, Dept Immunol, Sao Paulo - Brazil

• Document type: Journal article
• Source: Acta Tropica; v. 176, p. 455-462, DEC 2017.
• Web of Science Citations: 4

Abstract

Background: 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. Purpose: To georeference the distribution of Simuliidae (Diptera: Simuliidae) and Phlebotominae (Diptera: Psychodidae) and of PF cases in the northeastern region of Sao Paulo State, and to assess the humoral immune response against salivary gland extracts (SGEs) from biting flies in PF patients, relatives, and neighbours. Methods: 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 ware plotted. Serum IgG antibodies against the SGEs from Simulium nigrimanum, Nyssomyia neivai, and Aedes aegypti (as control) were determined by ELISA. Results: 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 < 0.001 for both), but not against the SGE from A. aegypti (P = 0.115 and P = 0.552, respectively), as compared to controls. IgG against the SGEs from S. nigrimanum and N. neivai but not against the SGE from A. aegypti correlated with levels of anti-Desmoglein 1 in PF patients (r = 0.3848, P = 0.039; and r = 0.416, P = 0.022, respectively). Conclusion: An epidemiological link between biting flies and PF in southeastern Brazil is proposed, implying a possible role of the salivary proteins from these flies in PF etiopathogenesis. (AU)

• FAPESP's process: 10/51729-2 - Relation between immunogenetics and environmental factors in a Brazilian epidemiological study of Pemphigus vulgaris and Pemphigus foliaceus
• Grantee: Ana Maria Ferreira Roselino
• Support Opportunities: Research Projects - Thematic Grants