In the early stages, malaria symptoms are sometimes similar to those of many other infections caused by bacteria, viruses, or parasites. Symptoms may include: Fever, Chills, Headache, Sweats, Fatigue, Nausea and vomiting. Symptoms may appear in cycles and may come and go at different intensities and for different lengths of time. But, especially at the beginning of the illness, the symptoms may not follow this typical pattern.