Reduced Household Illness and Economic Burden after Distribution of Point-of-Use Water Filters in Ciudad Victoria, Mexico

Background: Globally, over 2.1 billion people lack safe drinking water, leading to significant impacts, especially from diarrhea. This study evaluates the health and economic impacts of point-of-use water filter distribution in an urban setting with partial water infrastructure. Methods: In 2024 and 2025, households (N=7,973) in Ciudad Victoria, Mexico, re-ceived a hollow fiber membrane point-of-use water filter and basic WASH training. A pseudo-randomized study design was used to assign household to receive one of three different filter implementation systems (tap, bucket, or squeeze). Baseline and follow-up surveys with each household were conducted over an 8–14 week time frame. Results: Filter utilization was high across all three delivery types, with only minor differences in outcomes observed. Self-reported two-week diarrhea prevalence de-clined from 24.3% at baseline to 3.1% at 8–14 weeks, with similar reductions in oth-er health symptoms. Household water expenditures decreased by 56%, and work-days missed due to diarrhea declined by 94%. Impacts were similar in covariate ad-justed statistical models. Conclusions: This study suggests that point-of-use filtration combined with WASH training can substantially reduce illness and economic burden in urban contexts, with effectiveness comparable across different filter implementation approaches. Limitations include reliance on self-reported data and a short follow-up period, which should be explored in future studies.