By Dr. Rajashekhar, General Physician

Tropical fevers are defined as diseases that occur primarily in or are unique to tropical and sub-tropical areas. India is a haven for most tropical fevers, and they are most common during the monsoons or post-monsoon periods. The symptoms of the various fevers are overlapped to such an extent that it is necessary to get empirical medical treatment for its proper diagnosis.

There are various types of fevers that plague the society; the most wide-spread occurrences are of- Dengue, Malaria and Typhoid.

DENGUE (pronounced ‘den-gee’)

Causative Organism

It is caused by different strains of the dengue virus. These viruses reproduce and multiply within mosquitoes of Aedes type and its species, principally aegypti. Thus they are the carriers of the virus and are called vectors.

Signs and Symptoms-

Symptoms are typically seen a couple of weeks after infection. Every strain shows characteristic symptoms; sometimes may not show symptoms at all. The most common symptoms are-

  1. Nausea, vomiting
  2. Sudden rise in temperature
  3. Severe headaches
  4. Pain behind eye
  5. Joint and muscle pain
  6. Fatigue
  7. Skin rashes that appear 3-4 days after the onset of fever
  8. Loss of appetite


Causative Organism

Living in India, most of us are familiar with this disease. It is caused by the Malaria parasite and is transmitted by the bite of female Anopheles mosquito. When the mosquito bites a healthy individual after taking a blood meal from an infected individual, it passes on the parasite through its salivary glands.

Signs and Symptoms-

Mostly, the symptoms appear 14 days after the infection as the parasite reproduces in hepatic cells (the cells which store fat and found beneath the liver). The symptoms visible are-

  1. Chills, fever and sweating appearing in cycles
  2. Malaise, shivering
  3. Pain in muscles
  4. Pallor, headache, nausea


Causative Organism

It is a bacterial infection caused by ‘Salmonella Typhi’. It is a type of enteric fever and its root causes are poor sanitation and consumption of unclean water. It is most commonly seen in India.

Signs and Symptoms:

The symptoms appear within 6- 30 days of getting infected.

  1. Fever as high as 104 F
  2. Lethargy
  3. Diarrhoea
  4. Headaches, generalised pain
  5. Loss of appetite

These diseases, without proper treatment and diagnosis, can cause mortality and morbidity. Hence it is imperative to get vaccinated for these tropical diseases. If you wish to discuss about any specific problem, you can consult a general physician and ask a free question.