Background
The presence of a large informal healthcare sector in many low- and middle-income countries poses both challenges and opportunities for achieving a people-centered health system. However, few studies have considered how informal providers may fit into a people-centered health systems approach. We examine the self-described roles and motivations of informal medicine vendors and public healthcare workers in rural Nigeria, as well as interactions between them, with the aim of identifying how local health systems may be reoriented for improved service delivery through a people-centered approach.

Methods
We analyzed data from in-depth interviews with 70 medicine vendors and 21 staff of public health facilities in 30 villages across Kogi, Kwara and Enugu states in Nigeria. Interview guides covered the respondent’s or her facility’s role in providing health services to the local community, motivation to work in her respective profession, and relationships and interactions with other frontline healthcare providers. Data were analyzed in Atlas.ti using an open coding approach.

Results
Both medicine vendors and staff of public health facilities viewed themselves as fulfilling an essential primary healthcare function in their villages, and described their main motivation as the desire to help their communities. Medicine vendors were acknowledged by both groups to play an important role in providing care close to underserved rural communities, but within a limited scope of practice. Vendors described referring cases beyond their self-defined capacity to the local public facility. Health facility staff also sent clients to vendors to purchase drugs that were out of stock. However, referrals were informal and unspecific in nature, and the degree to which relationships between vendors and health facility staff were collaborative was highly context-dependent despite their recognized interdependencies in health services provision.

Conclusions
Policies aimed at fostering people-centered health systems should consider the role of informal providers in the delivery of integrated care. In the context of our rural study sites in Nigeria, supporting stronger and more consistent linkages between medicine vendors and public health facilities is a key step towards improving health service delivery.