Seasonal Frequency in Esophageal Atresia/Tracheo-Esophageal Fistula: Is there an Environmental Etiology?

Background: Esophageal Atresia and Tracheo-Esophageal Fistula (EA/TEF) occurs sporadically and its etiology is poorly understood. We observed six cases of EA/TEF within three weeks of October 2007 at the Lagos University Teaching Hospital (LUTH), Nigeria. Aims: To analyze the monthly trends of presentation of EA/TEF at the LUTH from 2002-7, test the hypothesis that the October figures were not due to chance and correlate data with known local disease patterns. Setting: Lagos University Teaching Hospital, Nigeria. Patients, Materials, Method: A retrospective analysis of all EA/TEFs managed at the LUTH within stated period. Results: 25 babies with EA/TEF presented over the period. 10 (40%) were seen in the month of October, 5 (20%) occurred in May while the rest were spread over the rest of the months. Chi-square analysis confirmed that the EA/TEF cases occurred significantly more frequently in October (P < 0.001) and this observation was unlikely due to chance. Conclusions: There seems to be a seasonal variation in the occurrence of EA/TEF in Lagos, with a significantly higher frequency in the month of October. 96% of mothers of babies with EA/TEF lived in low socioeconomic parts of Lagos. This study highlights the possibility of local viral etiology of EA/TEF.