03164nas a2200313   4500000000100000008004100001260003400042653002000076653002200096653002300118653003600141653002200177653002300199100002500222700001700247700001500264700001400279700001500293700001900308700001400327700001400341700001500355700001400370700002200384245014100406856007500547300000900622520221900631       2024                            d  bCold Spring Harbor Laboratory10aChagas' disease10aTrypanosoma cruzi10aFoodborne Diseases10aPolymerase Chain Reaction (PCR)10aDisease Outbreaks10aNeglected Diseases1 aAlves Simões-Neto E1 aSantos DWDCL1 aBomfim MRQ1 aCosta JML1 aSimões AF1 aVasconcelos LD1 aSodré DC1 aCosta ACM1 aDumont SVR1 aMelo BDOD1 ade Azevedo CDMPES00aAn outbreak of Chagas disease through oral transmission: 115 years after discovery by Carlos Chagas, the disease is still hard to manage  uhttps://www.medrxiv.org/content/10.1101/2024.05.24.24307628v1.full.pdf  a1-423 a<p><strong>Background: </strong>Orally transmitted acute Chagas disease (ACD) mostly affects low-visibility and low-income individuals, mainly in tropical and subtropical zones. However, even more than 100 years after Carlos Chagas’ discovery, several difficulties in managing ACD are still faced. Ita expansion to other, non-endemic areas through globalization processes has transformed it into a global health problem.</p>

<p><strong>Methodology: </strong>This report addresses an outbreak of 39 cases of ACD due to oral transmission. A clinical-epidemiological investigation with an entomological search was performed. Laboratory criteria (positive peripheral blood smear (PBS), seroconversion of IgG and 2x increase in IgG titer) and clinical-epidemiological criteria (clinical findings, epidemiological exposure and at least one positive IgG) were used for diagnoses. In-house conventional polymerase chain reaction (PCR) was performed on 33 samples. All patients were treated with benznidazole. After 4.5 years, IgG was investigated in 26 individuals. Their mean age was 33.6 years, with no difference in gender distribution; the mean incubation period was 13.8 days and mean time between symptom onset and treatment was 16.6 days.</p>

<p><strong>Findings: </strong>The most frequent symptoms were fever and lymphadenopathy (90%). For 66.6%, laboratory criteria yielded the diagnosis and for 23%, clinical-epidemiological criteria, while 10.2% showed negative tests but were treated due to high clinical suspicion. Test positivity rates: PBS 69.7%; serology 91.4%; PCR 100%. There were no deaths. Serological cure was achieved for 34.6% and decreased IgG titers for 15.3%.</p>

<p><strong>Conclusions and significance: </strong>We present all the barriers encountered in managing real-life situations: vulnerability of the population; dependence on old diagnostic techniques; lack of standardization of molecular biology techniques; and few therapeutic options. We demonstrated the importance of rapid surveillance action with early treatment, such that this outbreak did not give rise to deaths. We also propose that conventional PCR should become standardized within the diagnostic routine.</p>