There is an urgent need to develop an automated malaria diagnostic system that can easily and rapidly detect malaria parasites and determine the proportion of malaria-infected erythrocytes in the clinical blood samples. In this study, we developed a quantitative, mobile, and fully automated malaria diagnostic system equipped with an on-disc SiO 2 nanofiber filter and blue-ray devices. The filter removes the leukocytes and platelets from the blood samples, which interfere with the accurate detection of malaria by the blue-ray devices. We confirmed that the filter, which can be operated automatically by centrifugal force due to the rotation of the disc, achieved a high removal rate of leukocytes (99.7%) and platelets (90.2%) in just 30 s. The automated system exhibited a higher sensitivity (100%) and specificity (92.8%) for detecting Plasmodium falciparum from the blood of 274 asymptomatic individuals in Kenya when compared to the common rapid diagnosis test (sensitivity = 98.1% and specificity = 54.8%). This indicated that this system can be a potential alternative to conventional methods used at local health facilities, which lack basic infrastructure. Globally, malaria is one of the "big three" infectious diseases with an incidence rate of 57 cases per 1000 individuals 1. Malaria is a vector-borne disease, which is caused by infection from Plasmodium spp. and is transmitted by Anopheles mosquitoes. The United Nations Sustainable Development Goals had proposed to end the epidemic of malaria by 2030 2. Although the annual fatality rate has decreased since 2016, about 405,000 malaria-related deaths were reported in 2018. Similarly, new malaria cases have increased slightly since 2014 with 231 million recorded cases in 2017 and 228 million recorded cases in 2018 3. Several factors have stagnated global progress in eradicating malaria 4. Particularly, most tools to tackle the current malaria infection were developed before 2000. Thus, there is a need to develop new tools using novel technologies to accelerate the efforts toward malaria elimination 4 .

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The characteristics of the optical trapping force, optical torque, and viscous drag force for a newly proposed cylindrical optical rotator are analyzed. The optical trapping force and torque are evaluated by use of a ray optics model for both parallel and focused laser beam illumination. The drag force is calculated from computational fluid dynamics to be the sum of the components of both the pressure and the shearing stress on all the surfaces of the rotator. We analyze the rotation rate by balancing the optical torque with the drag force. A cylindrical optical rotator is expected to rotate at a high speed because of its highly efficient generation of optical torque and its small viscous drag force.