This paper presents the prevalence of parasitic infection three weeks after a de-worming process in August 2010 of a community in Valencia, Bukidnon, Philippines. Using mixed methods, the authors obtained data from the 203 schoolchildren and the parents of the infected school children. Thirteen schoolchildren had parasitic infections, and hookworm was the most prevalent parasite observed. This suggests resistant infection or rapid reinfection after the de-worming process. The infection could have occurred especially with the children playing barefooted in contaminated watery areas. The free-living pets that came in and out of their houses could have contributed to the rapid reinfection. The 13 infected children had cough and colds, abdominal pain, manifested pallor, and suffered body weakness. Five of the infected children experienced loss of appetite and four had BMI below the normal range based on the Philippine BMI standards. No differences were found in the environmental sanitation and hygienic practices between those schoolchildren who were (13) and were not (190) infected with parasites. The parents interviewed reacted with wonder, worry, and anger, and received confirmation for their suspicions about their children’s condition. They were happy that May 2011 is scheduled for another de-worming procedure.