As the northern region of Vietnam enters its transitional season with high humidity and frequent rain, conditions are ripe for the spread of dengue fever. Dengue fever has different stages, and each stage has its own risk and symptoms.

The early rainy season is when dengue fever spreads rapidly and can easily escalate into outbreaks. Patients with dengue fever may self-treat and rest at home. However, warning signs such as bleeding gums, vomiting blood, and passing black stools require immediate hospital visits, as they indicate severe dengue.