Infection with soil-transmitted helminths (STHs) is a major public health problem in many developing countries; pregnant women and children are particularly at risk. Preventive chemotherapy (PC) -the intervention currently recommended by the World Health Organization (WHO) against the main helminth infections, including those caused by STHs -aims at reducing morbidity through periodical administration of anthelminthic drugs either alone or in combination.The Expanded Programme on Immunization (EPI) is one of the most widely implemented health programmes in the world and has a well-established access to children and women. The present study investigated the cost of the provision of anthelminthic drugs during existing immunization campaigns.In Lao PDR the use of this integrated approach compared to implementation of the vertical deworming campaign alone allowed reduction of the individual cost of deworming by 10 times (from US$0.25 in the vertical deworming campaign to US$0.02 in the integrated campaign). Burden posed on health workers by the integration process was perceived as minimal and manageable. Besides, delivery of anthelminthic drugs during the immunization campaigns enabled Authors' contributions: All the authors conceived and designed the study; GB conducted the questionnaire survey; GB, PEA, KF, AZ, KP, KS, CC and SP collected the budget data; GB and AY carried out data analysis; GB, AY, AFG, CP and AM interpreted the results of the analysis; GB and AY prepared the draft manuscript, all the authors critically reviewed and gave final approval of the version to be published. AM is the guarantor of the paper. Conflicts of interest: None declared.Ethical approval: As the study was carried out as a part of the vaccination campaign, ethical approval was not required. Informed consent was obtained by all the interviewees prior to the questionnaire survey. Europe PMC Funders Group Europe PMC Funders Author ManuscriptsEurope PMC Funders Author Manuscripts campaign teams to directly observe drug intake, which assured safety. Our findings prove that integration is an opportunity to maximize health benefits through the delivery of multiple health products and the attainment of a high coverage.