One of the public health problems in Batubara Regency of North Sumatra Province is malaria. Fluctuations in malaria cases can be caused by delayed diagnosis. This fluctuation can be overcome by knowing the characteristics of malaria patients in each region. Such characteristics are necessary in an effort to break the disease transmission. This study aims to determine the characteristics of patients with malaria in hypoendemic area. This is a longitudinal study in which each research subject was only exposed for 2 periods of malaria suffering during the study. The samples are people who live permanently in the research area and have risk factors for malaria exposure. The diagnosis was done through microscopic examination. The study found 671 people with malaria, with clinical malaria in the highest proportion (53.5%) and submicroscopic malaria in the lowest proportion (14.0%). The most common cause of malaria is Plasmodium vivax (63.6%). Parasite density in the category cases of clinical malaria was higher than the other two categories. There was no significant difference between the categories of malaria by age group (p = 0.434) and clinical symptoms (p = 0.333). However, there was a significant difference in hemoglobin levels in clinical malaria cases as compared to cases of asymptomatic malaria and submicroscopic malaria. The presence of asymptomatic malaria and submicroscopic malaria needs to be addressed by extending the examination of malaria in suspected patients, in an attempt to break the transmission of this disease.

Keywords: age group, fever, hemoglobin level, malaria