How does our body fight infections? After we get infected with a serious illness, in what ways does our immune system prepare? Understanding these processes could help hone treatments and vaccinations. According to Medical XPress, researchers from the Karolinska Institutet sought to understand how the immune system confers protection against malaria following infection. In particular, the researchers wanted to understand how recovering from a malarial infection could help people build up tolerance against severe disease in the future.

Interested in learning more? Take a look at the study findings published in Cell Reports. 

About the Research

To begin evaluating malarial tolerance, the research team first sourced blood samples from individuals who had been treated for, and later recovered from, malaria. Altogether, the researchers sourced samples from 53 individuals. Of these individuals, 17 (32%) had only had malaria once. The remaining 36 individuals (68%) had been infected with malaria more than once. Through these individuals, researchers were able to better understand how the immune system responds to this infection. 

Researchers found that the 32% of people who had never before had malaria saw a strong inflammatory response from the innate immune system (the immune defense system with which you are born). However, the 68% who had been previously infected with malaria were able to suppress the inflammatory response using parasite-specific antibodies. This inflammation reduction helped with disease management. Additional findings can be found in Nature Communications. 

Moving forward, the researchers hope that understanding more about this immune response can help scientists craft more effective vaccines to combat malarial infection. 

What is Malaria?

Malaria is a serious mosquito-borne illness caused by Plasmodium malariae, P. vivax, P. ovale, or P. falciparum parasites. People become infected through the bite of an infected mosquito. However, malaria may also be transmitted through blood transfusions, sharing needles, or from mother to child. While there are around 2,000 cases each year in the United States, this illness is more common in areas such as South Asia and sub-Saharan Africa. Without treatment, this illness can be fatal. Many of the fatalities occur in young children or elderly individuals in areas where this illness is endemic. 

Symptoms typically begin with 10 days to 1 month following infection. While some individuals experience constant symptoms, others experience “attacks” of symptoms. When symptoms appear, these may include:

• High fevers
• Nausea and vomiting
• Muscle pain
• Fatigue
• Shaking chills and cold sweats
• Abdominal pain
• Coughing
• Anemia (low red blood cell count)
• Low blood sugar
• Organ failure
• Difficulty breathing
• Cerebral malaria

Learn more about malaria.