Regional Medical/Malaria Officers (RMO) has performed a key role in malaria control/elimination/prevention of re-establishment programmes in Sri Lanka. They carried out district-level implementation of malaria control programme under the direction of the Director, Anti-Malaria Campaign before decentralization of malaria control activities to Provinces in 1989. After the devolution of health administration to Provincial Councils, their role is changed as technical advisors to the Regional Directors of Health Services and Medical Officers of Health, the latter has been entrusted the implementation of the control/elimination/POR activities.

A region is generally referred to as a district but some districts such as Kurunegala and Ampara are divided into several RMO regions. During the past before the decentralization, regions were not essentially coincided with the administrative districts. Some regions due to the size of the malarious parts were sub-divided into sub-regional offices which were managed by a senior PHI.

The post was originally designated as Regional Medical Officer (Anti-Malaria Campaign) and manned by medical officers who obtained a medical degree in a recognized university. However, during the early 1980s due to the dearth of medical officers at that time, a policy decision was taken to recruit biological science graduate who followed a four-year course in Zoology special degree with entomology and/or parasitology as a subject through Sri Lanka Scientific Service (SLSS). Those officers have been designated officially Regional Officers (Anti-Malaria Campaign) but both medical and SLSS officers have been commonly referred to as Regional Malaria Officers (RMOO). RMOO belong to SLSS have to obtain a Masters or Ph.D. in entomology or parasitology at a certain point in their career as an efficiency bar.   This step provided a strength to the campaign since long-term functioning officers with academically qualified as well as rich in experience have been engaged in controlling and eliminating malaria in Sri Lanka. 

At present RMOO are responsible for gear the prevention of reintroduction of malaria (PORM) programme at district level under the technical guidance of the National Directorate of Anti-Malaria Campaign. This task is much more challenging than malaria control as it needs innovative approaches to ensure tracking risk population, assessing local receptivity and vulnerability and to ensure preparedness at the local level to prevent transmission risk whenever it requires. In addition to their responsibilities in the PORM, RMOO also contributes to control of other vector-borne diseases prevailing in their regions such as dengue and leishmaniasis.