Introduction

Excessive sweating can be both a symptom and a sign of an underlying condition. It refers to a situation where your body produces more sweat than usual in an attempt to regulate its temperature. On the other hand, fever is a psychological disorder in which your body temperature rises above the normal range, typically above 37.5°C (99.5°F). It is important to understand the connection between fever and excessive sweating, as these symptoms often occur together in response to infections or other health issues. Recognising the link between them can help you identify potential causes early and seek the appropriate medical attention, as various infections, such as viral or bacterial diseases, can trigger both fever and excessive sweating. Early detection and action are crucial for managing these symptoms and addressing the underlying cause effectively.^1,2

Common infections that cause fever and sweating 

Respiratory infections

Influenza (Flu)³

Flu symptoms can come very sudden and typically last for about a week or so. Common symptom can include:

• Sudden fever
• Headache
• Feeling unwell
• Sweating or shivering
• Cough, sore throat
• Fatigue
• Muscles or joint aches, etc

Cause: it is caused by a virus and it easily spreads, usually during winter months. 

Management/treatment: symptomatic treatment including rest and sleep, stay warm, and drink plenty of fluids. You can take paracetamol or ibuprofen for your fever and aches or pain. Antiviral medication should be prescribed by your doctor. You can also get flu vaccines.

Pneumonia⁴

Pneumonia symptoms can range from mild, where you barely notice them, to severe, that need urgent medical attention. Common symptoms can include:  

• Cough
• Fever (greenish, yellowish or mucus that contains blood)
• Sweating and shaking chills
• Shortness or breath
• Rapid and shallow breathing
• Sharp chest pain
• Fatigue
• Loss of appetite
• Confusion (usually in older people), nausea and vomiting (children)

Cause: Pneumonia that is caused by bacteria called Pneumococcal Pneumonia. Some types of bacteria that can cause Pneumonia are Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila. Viruses that infect the respiratory tract can also cause Pneumonia, such as SARS-CoV-2, Influenza virus, and the most common is Respiratory syncytial virus (RSV). Fungus can also cause Pneumonia that is most common with some people who have chronic health issues or weakened immune systems. Pneumocystis Jirovecii, Coccidioidomycosis, Histoplasmosis, and Cryptococcus are some fungus that can cause Pneumonia. 

Management/treatment: antibiotics for bacterial pneumonia, antiviral for pneumonia that is caused by viruses. Symptom management such as paracetamol or ibuprofen to treat fever, lots of rest, plenty of fluids, stay away from smoke to heal your lungs. If you are hospitalised, you might be given intravenous fluids and antibiotics, and oxygen for your breathing treatment. 

Tuberculosis⁵

It is an infection that usually affects the lungs. However, it can affect other parts of the body as well. 

Symptoms can include:

• Cough for more than 3 weeks (cough can contain mucus or blood)
• Fever and night sweat
• Feeling tired or exhausted
• Loss of appetite and weight loss
• For children it might be difficult to gain weight or grow
• Swollen glands
• Swollen joints or ankles, etc

Cause: Tuberculosis caused by bacteria called Mycobacterium tuberculosis, other mycobacteria (such as Mycobacterium bovis) can also cause TB disease.

Management/treatment: combination of antibacterial medication for about six to twelve months. It is very important to take your medication exactly as prescribed from your doctor recommendation for the full duration of your treatment. Stopping early may increase the risk of getting sick again, make it harder to fight the disease in the future, and put others at risk of infection. Moreover, not completing your full course of treatment could contribute to the development of drug-resistant tuberculosis.

Viral infections

Dengue fever^6,7

It is a viral infection that spreads by Aedes aegypti mosquitoes, which is more common in tropical and subtropical climates. Incubation period is usually between 3-15 days. 

Symptoms begin with:

• Fever
• Chills 
• Headache
• Retro-orbital pain when moving eyeballs
• Back Pain
• Pain in joint and leg
• Temperature increase rapidly to 40° C
• Eyeball and face will appear red, and usually disappear quickly
• Enlarged gland on the neck and throat
  • After 48-96 hours, fever and other symptoms will be followed by a rapid decrease of  temperature and excessive sweating. This period usually lasts for a day then temperature may increase again (saddleback pattern). This time, maculopapular rash will appear all over their body and face
  • Some patients might develop dengue haemorrhagic fever or Guillain-barre syndrome

Management/treatment: There is no specific antiviral treatment. Symptomatic treatment can help to ease your symptoms, such as rest, drink plenty of fluids, and paracetamol to treat fever and ease the pain. Anti Inflammatory painkillers such as Ibuprofen or aspirin are not allowed to be taken as it will increase the risk of bleeding. 

Bacterial infections

Sepsis⁸

It is a life threatening condition where the body has severe widespread inflammations that are caused by bacteria or other germs. 

Symptom can include: 

• Earliest symptoms : change in mental status and tachypnea (very fast breathing)
• Chills, sweating
• Fever or hypothermia
• Confusion or delirium
• Headache due to low blood pressure
• Rapid heartbeat
• Skin rash
• Warm skin 

Management/treatment: patients must be treated at the hospital and receive immediate intravenous antibiotics, dialysis, fluids, oxygen or ventilator for breathing if needed, and might have surgery.

Typhoid fever⁹

It is a disease caused by bacteria called Salmonella typhi. 

Symptom can include: 

• High temperature that is constant and gradually increase everyday up to 39-40℃
• Headache
• Reduced or loss of appetite
• Feeling sick, constipation, diarrhoea
• Easily get tired, fatigue
• Excessive sweating caused by the high fever 
• Cough
• Rash on the skin
• Swelling in the abdomen

Management/treatment: depending on severity, some cases can be treated at home. Doctors usually prescribed antibiotics and intravenous fluids. Limit activities, rest, eat small portions but often and eat low fibre, are recommended. 

Leptospirosis¹⁰

It is an infectious disease that is caused by bacteria called Leptospira. 

Symptom can include: 

• High temperature 
• Chills, sweat
• Headache
• Reduced appetite
• Severe muscle pain
• Nausea/vomiting
• Splenomegaly and hepatomegaly may occur

Management/treatment: antibiotics such as penicillin, oral doxycycline, streptomycin, chloramphenicol, and erythromycin.

Endocarditis¹¹

It is a life threatening condition that is caused by bacteria in your bloodstream and spreading in the endocardium. 

Symptom can include: 

• High temperature
• Chills, night sweat
• Cough
• Headache
• Shortness of breath
• Fatigue
• Muscle and joint pain

Management/treatment: antibiotics usually for 2-6 weeks, and possibly surgery if needed. 

Parasite infections

Malaria¹²

Malaria is a serious infection caused by a parasite, specifically a protozoan parasite of the genus Plasmodium. The parasite is transmitted to humans through the bite of infected female Anopheles mosquitoes. There are several species of Plasmodium that can cause malaria, with Plasmodium falciparum and Plasmodium vivax being the most common. Malaria is most commonly found in tropical and subtropical countries. Symptom of this illness include: 

• Cold stage (first stage): fever, shivering, goosebumps, tooth clenching, coughing, shortness of breath, high blood pressure, rapid pulse, a cold body, nausea, vomiting, and frequent urination
• Hot stage: fever, hot body and breath, a pale mouth, thirst, a rapid pulse, high blood pressure, a red face, red skin, dry skin, eye socket pain, nausea, vomiting, diarrhoea, a severe headache, and restlessness. In this stage, young children might experience convulsions
• Sweating stage: fever begins to subside and then followed by sweating and chills. The body temperature drops rapidly, and the blood pressure will return to normal, followed by extreme tiredness and falling asleep

Management/treatment: prompt treatment with antimalarial drugs (e.g., chloroquine, artemisinin-based therapies).

Skin infections

Cellulitis¹³

It is a common skin infection caused by bacteria that usually affects the dermis layer of the skin. 

Symptom can include:

• Fever with sweating and chills
• Fatigue
• Pain and tenderness on the affected area of the skin
• Rash that develops quickly in one day
• As the infection spread, skin inflammation gets bigger 
• Swelling of the tissue over the joint caused muscle pain and joint stiffness
• Feeling sick and vomiting

Management/treatment: antibiotics and painkillers if needed.

When to seek Medical Help

You should seek medical attention if someone is experiencing fever and excessive sweating in any of the following situations:^2,14

• Persistent fever
• Difficulty breathing
• Chest pain
• Severe headache 
• Lightheadedness
• Losing consciousness
• Seizure
• Dehydration
• Worsening symptoms

Conclusion 

It is important to be mindful when you know someone experiencing fever and excessive sweating. You need to immediately seek medical attention, as these could be signs of a serious infection that requires prompt treatment. Infections such as malaria, pneumonia, sepsis, and tuberculosis can cause these symptoms and, if left untreated, may lead to complications or become life-threatening. Early diagnosis and appropriate treatment can help manage the infection, reduce the risk of severe outcomes, and prevent the spread of the disease to others. Be sure to inform your healthcare provider about any additional symptoms, recent travel history, or exposure to infectious agents, as this information can aid in a quicker and more accurate diagnosis.