Detection of serum anti-lipopolysaccharides (LPS) antibodies from enterohemorrhagic E. coli (EHEC) in asymptomatic kindergarten teachers of Buenos Aires Province

FERNANDEZ BRANDO ROMINA; SACERDOTI FLAVIA; AMARAL MARÍA MARTA; BERNAL ALAN MAURO; MARCELO DA ROCHA; BELARDO MARCELA; PALERMO MARINA S; IBARRA CRISTINA

Congreso; Reunión de las Sociedades de Biociencias; 2020

SAIC, SAI, SAFIS

 EHEC is responsible for developing typical HemolyticUremic Syndrome (HUS) and Argentina has the highest incidence in the world. Theendemo-epidemic behavior that HUS presents in our country was associated toperson-to-person transmission. Since children below 5 years old are the most affected,our objective was to determine the frequency of kindergarten teachers with anti-LPS-EHECantibodies in serum.One hundred and fifty teachers from J.C. Pazdistrict from Buenos Aires Province participated in an informative talk given byLuSUH, a non-governmental association, about goodpractices to reduce HUS transmission. Then, 63 of them voluntarily gave, undera signed written informed consent, a sample of blood obtained by fingerpuncture. A commercial ELISA (Chemtest, Arg) was used to detect specific IgMand IgG isotypes against 4 types of LPS-EHEC: O157, O145, O121 and O103. These variantsrepresent approximately 87% of the EHEC serotypes associated to HUS inArgentina. The IgM finding was considered as an indirect evidence of currentinfection with the EHEC specific serotype.Sixty percent (25/42) of the evaluated serawere positive for at least one type of LPS. Approximately half of them (14/25) wereIgM positive. Fifty percent of the positive samples were reactive for LPS O157,26% for LPS O121, 12% for LPS O145 and 2% for LPS O103. Among the samplespositive for LPS O157, 5% belonged to IgM isotype, 31% to IgG and 14% had both.The IgG isotype was the unique detected for LPS O145 and O103 (12 and 2%,respectively). For LPS O121, the IgM isotype was detected in 2%, IgG in 12% andboth isotypes in 12% of the samples.The elevated frequency of LPS-EHEC reactivesamples (60%) reflects the high circulation of EHEC strains in our country. Thisagrees with the prevalence of anti-Stx2 antibodies reported in our populationpreviously. Very strikingly, nearly half of these individuals carry IgM,suggesting that they would be in the active phase of infection.<!-- /* Font Definitions */ @font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:roman;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:swiss;mso-font-pitch:variable;mso-font-signature:-1610611985 1073750139 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:10.0pt;margin-left:0cm;line-height:115%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-fareast-language:EN-US;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-size:10.0pt;mso-ansi-font-size:10.0pt;mso-bidi-font-size:10.0pt;font-family:"Calibri",sans-serif;mso-ascii-font-family:Calibri;mso-fareast-font-family:Calibri;mso-hansi-font-family:Calibri;}size:612.0pt 792.0pt;margin:70.85pt 3.0cm 70.85pt 3.0cm;mso-header-margin:35.4pt;mso-footer-margin:35.4pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}