If you experience chills and recurring fever after traveling to border regions or abroad, it is natural to feel anxious about whether it is a simple cold or symptoms of malaria. While malaria initially begins like body aches, checking the pattern of chills and high fever along with your travel history can help you avoid missing the optimal time for testing.
You should be especially careful if you experience a fever every other day or if you feel better for a while after sweating profusely. I will explain the early signs of malaria, the fever cycle, and when you should seek medical attention after visiting a high-risk area, in order.
Malaria Symptoms, the First Signs to Look For
Malaria is infected Female spotted-winged mosquitoIt is an infectious disease caused by transmitting protozoa through a human bite. In the early stages, it often presents with a sudden fever and shivering, accompanied by headaches, fatigue, and muscle pain.
A typical pattern involves a high fever following chills, followed by a drop in temperature after sweating. However, since this cycle may not be distinct from the start, it is important not to take the fever caused by a mosquito bite in a high-risk area lightly.
Digestive symptoms such as vomiting, diarrhea, and loss of appetite may also accompany it. Even though it looks similar to a cold Severe chills and recurring feverIf this overlaps, it should be considered a sign that a malaria test is necessary.
If you develop a fever after visiting a high-risk area, the key is to inform medical staff of your travel, residence, and outdoor activity history before notifying them of the fever symptoms.
A fever cycle consisting of chills, high fever, and sweating
A typical malaria attack progresses in the order of chills, high fever, and sweating. The chills can last from about 30 minutes to 2 hours, and during this time, it feels so cold that the shivering does not stop even when covered with a blanket.
This is followed by a high fever phase that can last for several hours, with body temperature rising to 39–41°C. When the fever drops, you sweat profusely and feel weak, and the sweating phase may last for about 4 to 6 hours.
Plasmodium vivax malaria, which primarily occurs in Korea, can manifest as a form where a fever occurs one day and is fever-free the next. However, this does not mean that a fever must occur every other day for it to be malaria, and, Early symptoms of an irregular cycleIt is also eligible for medical treatment.
What is the difference between this and a cold or body aches?
While colds and the flu also cause fever and muscle aches, malaria often begins with severe chills followed by high fever and sweating. You may feel fine when the fever subsides, but the same symptoms may recur, which can significantly disrupt your daily routine.
Another clue is time. Symptoms appear after an average incubation period of about 12 days for Plasmodium falciparum, about 14 days for Plasmodium vivax and Plasmodium ovale, and about 30 days for Plasmodium tetragonum.
Plasmodium vivax and Plasmodium ovale are affected after infection due to the form remaining in the liver. Onset even after 6 to 12 monthsYou can do it. That is why you shouldn't just think of summer outdoor activities, but also mention your previous travels or experiences staying in border regions.
Where do I need to get tested after visiting?
Domestic malaria outbreaks occur mainly in areas adjacent to the Demilitarized Zone, such as northern Gyeonggi Province, Incheon, and parts of Gangwon Province. In 2026, a nationwide malaria advisory was issued on June 22, and the level was raised to a nationwide alert on August 13.
Overseas, sub-Saharan Africa, parts of Southeast Asia, the Amazon basin, the Indochina Peninsula, and Papua New Guinea are considered major risk areas. In particular, in tropical Africa, vigilance must be exercised against Plasmodium falciparum malaria, which can progress to a severe condition if treatment is delayed.
| situation | Symptoms to watch out for | Information to convey during the consultation |
|---|---|---|
| Visited or stayed in northern Gyeonggi, Incheon, and parts of Gangwon | Fever, chills, headache, cold sweat | Visiting area and outdoor activity dates |
| Returned home after traveling through Africa, Southeast Asia, and the Amazon basin | High fever, vomiting, diarrhea, severe fatigue | Country, duration of stay, date of return |
| Fever after visiting a high-risk area several months ago | Recurring fever, chills, and sweating | Previous travel history and symptom onset date |
If you develop a fever or severe chills after visiting a high-risk area, you should seek medical attention and report any potential exposure to malaria. It is not a disease transmitted through everyday contact such as shaking hands or sharing meals, but it can rarely be spread through blood transfusions or the shared use of contaminated syringes.
How is malaria tested, and why is treatment urgent?
Diagnosis involves examining blood under a microscope blood smear test, Rapid diagnostic tests that detect antigens from a single drop of blood, and PCR tests that more precisely distinguish between types of protozoa, are utilized. Since this method detects protozoa in the blood while symptoms are present, providing information on fever and travel history together speeds up the treatment process.
Treatment varies depending on the type of parasite and severity. For Plasmodium vivax malaria, chloroquine is used to eliminate parasites in the blood, and primaquine is used to eliminate latent parasites remaining in the liver, while for Plasmodium falciparum malaria, combination therapy with artemisinin (ACT) is used as the standard treatment.
If Plasmodium falciparum malaria is not treated in time, it can lead to severe complications such as kidney failure, respiratory failure, and cerebral malaria. If you have a fever and a history of visiting a high-risk area, seek medical attention on the same day.This is the reason why it is necessary.
Prevention to Avoid Mosquito Bites and Pre-Travel Preparation
Generally, you do not take preventive medication when visiting domestic border regions. On the other hand, when traveling to high-risk areas abroad, you must consult with medical professionals before departure to plan your preventive medication based on the types of protozoa and resistance status of the destination.
Wearing long-sleeved shirts and long pants from dusk until night, and using mosquito repellent and screens together, is helpful. In accommodations, the basic rule is to minimize areas where mosquitoes are likely to linger, such as gaps in windows, around bedding, and near doorways.
Malaria is not a disease caused simply by the abundance of mosquitoes; it is transmitted when exposed to mosquitoes carrying the infectious parasite. Therefore, when assessing fever during the summer, do not look at just one symptom, I don't know when or where it wasAddressing this together is the most realistic starting point.