Fever is a common symptom of many infections, but its cause may not always be clear from symptoms alone. Infections such as dengue, malaria and typhoid can have overlapping symptoms, particularly in the early stages.
If fever persists or is accompanied by other concerning symptoms, appropriate laboratory testing can support clinical assessment. LifeCell Fever Comprehensive Panel includes a set of tests to investigate some common causes of fever.
What Is a Fever Panel?
A fever panel is a combination of laboratory tests used to investigate possible causes of fever. Depending on the panel and the clinical situation, it may include tests for infections such as dengue, malaria and typhoid. ¹
These infections have different causes and require different diagnostic tests. However, their symptoms can overlap, especially in the early stages, so symptoms alone may not identify the cause of fever.
Testing for Dengue: What Is Tested on the Fever Panel?
Dengue is a viral infection transmitted by infected mosquitoes. Common symptoms include fever, headache, pain behind the eyes, muscle and joint pain, and rash. The most appropriate dengue test can vary depending on how long the person has had symptoms.
Dengue NS1 Antigen and Molecular Testing
During the first 7 days of illness, dengue can be detected using NS1 antigen testing or molecular tests such as RT-PCR. CDC guidance recommends using either NAAT or NS1 antigen testing together with an IgM antibody test during this phase.
NS1 testing detects a dengue viral protein, while RT-PCR detects dengue viral RNA. A positive result can support a diagnosis of acute dengue infection. However, a negative NS1 or RT-PCR result does not completely rule out dengue. Results should be interpreted based on the timing of testing, symptoms and other clinical findings.
Dengue IgM Testing
Dengue IgM antibodies are usually detectable around 4–5 days after symptom onset and become more useful later in the course of illness. From around day 7, IgM testing is a key method for diagnosing dengue.
A positive IgM result can indicate a recent dengue infection, but cross-reactivity with antibodies from other infections may occur. Therefore, results should be interpreted alongside the timing of illness, symptoms and other clinical findings by a healthcare professional.
Malaria Testing: Why Prompt Diagnosis Matters
Malaria is caused by Plasmodium parasites, which are transmitted by mosquitoes. Fever is one of the symptoms of the disease, and malaria can be a life-threatening disease, especially if caused by Plasmodium falciparum. According to the WHO, prompt parasitological testing of people with suspected malaria is highly recommended.
Malaria Rapid Diagnostic Tests
A malaria rapid diagnostic test detects specific parasite antigens in the blood. They offer fast results and are especially helpful in situations where reliable microscopy is unavailable.
Different RDTs detect different antigens from the malaria parasite and may not detect all Plasmodium species. A negative result may not eliminate the need for further clinical evaluation when malaria is strongly suspected.
Typhoid Testing: Understanding the Available Tests
Typhoid fever is a systemic illness caused by Salmonella Typhi. Some of the common symptoms include fever, headache, fatigue, abdominal pain, and constipation or diarrhoea. Nonetheless, the symptoms are not unique to typhoid fever, and laboratory testing is required to confirm the diagnosis.
Blood Culture for Typhoid
Blood culture is the mainstay of laboratory diagnosis for typhoid fever. It involves testing a blood sample to detect Salmonella Typhi.
A single blood culture may not detect every infection, so multiple cultures may sometimes be required. If the bacteria are isolated, they can also be tested for antimicrobial susceptibility, which helps healthcare professionals select appropriate treatment.
When Should Fever Testing Be Considered?
Not every fever requires comprehensive testing. The need for testing depends on factors such as symptoms, fever duration, exposure history, local disease patterns and medical history.
Testing may be considered when the cause of fever is unclear or symptoms overlap across infections. The choice of tests also depends on the suspected infection and stage of illness.
A comprehensive panel may be useful when multiple infections need to be considered. LifeCell Fever Comprehensive Panel includes tests for several common infectious causes of fever.
Conclusion
A fever panel may help investigate common infectious causes of fever when symptoms alone do not identify the cause. Depending on the infection and stage of illness, testing may include dengue NS1 antigen, molecular or IgM testing, malaria microscopy or rapid diagnostic tests, and blood culture for typhoid.
The appropriate tests depend on the patient’s symptoms, illness duration and clinical assessment. Anyone with persistent or concerning fever should consult a doctor to determine the tests needed.
