What are Vector-Borne Diseases?

Vector-borne Diseases Explained

Vectors are living organisms that carry infectious germs or pathogens. They can bite humans or animals and spread these pathogens, resulting in vector-borne diseases. Around 700,000 deaths are reported every year due to various vector-borne diseases. They contribute to more than 17% of all infectious diseases caused by bacteria, viruses, and parasites.

Once infected, vectors can transmit germs throughout their lives whenever they bite a host organism. Malaria, dengue, chikungunya, plague, and yellow fever are all examples of diseases that are transmitted through vectors.

Keep reading to learn more!

What are the Causes of Vector-Borne Diseases?

The action of specific pathogens and vectors causes vector-borne diseases. They act as carriers of disease-causing pathogens that they transmit to humans while sucking their blood. Generally, these are insects from the arthropod species, like mosquitoes, ticks, triatomine bugs, sandflies, and blackflies.

Listed below are various vector-borne diseases and their causes:

• Chikungunya, dengue, yellow fever, and zika are all illnesses caused by a virus that is spread by the Aedes mosquito.
• Malaria is caused by the parasite that is transmitted through the bite of the female Anopheles mosquito.
• Japanese Encephalitis and West Nile Fever are caused by the action of a virus carried by the Culex mosquito.
• Chagas Disease is caused by a parasite carried by the Triatomine bugs. It is also known as American trypanosomiasis.
• Sleeping Sickness is caused by a parasite carried by the Tsetse fly. It is also known as African trypanosomiasis.
• Leishmaniasis is caused by the action of a parasite carried by sandflies.
• Typhus is a disease caused by the transmission of a bacterium through the bite of infected lice.
• Plague is caused by the action of bacteria carried and transmitted by fleas from rats to humans.
• Crimean-Congo Hemorrhagic Fever is caused by the action of a virus carried by ticks.
• Lyme Disease is caused by the action of bacteria carried by deer ticks.
   

Several factors, like the environment, population density of a certain area, and frantic urbanization, can contribute to the spread of various vector-borne diseases. These disease-causing vectors thrive well in areas with still water bodies and tall grass growth.

Such regions may report large outbreaks of vector-borne diseases, and you are at greater risk if you stay closer to these areas.

What are the Common Symptoms of Vector-Borne Diseases?

Symptoms of vector-borne diseases can differ based on the conditions and the disease-causing germ or pathogen. Listed below are the symptoms of some common vector-borne diseases:

1. Chikungunya

The most common symptom of chikungunya is persistent joint pain that can persist for several weeks. Other symptoms like sudden fever, body aches, headache, nausea, fatigue, and rashes on the skin can also be seen.

2. Dengue

It is characterized by a high fever that goes up to 40 degrees C. Fever is often accompanied by severe headache, pain behind the eyeballs, muscle aches, joint pain, nausea, vomiting, swollen lymph nodes, and rashes.

3. Yellow Fever

Common yellow fever symptoms include high fever, severe back pain, chills, headaches, loss of appetite, and nausea. It can go away within three to four days.

However, these symptoms can recur and worsen to a dangerous level, causing gastric bleeding, jaundice, dark-colored urine, stomachache, and vomiting. About 50% of the cases that enter this phase report deaths.

4. Zika

The majority of individuals infected with the Zika virus typically do not exhibit any noticeable signs or symptoms. Only about 20% of the people affected can experience mild symptoms like low fever, conjunctivitis, headache, joint stiffness, muscle pain, and pain behind the eyes.

Sometimes, these symptoms may also give rise to neurological disorders like Guillain-Barre syndrome.

5. Malaria

Common symptoms of malaria are fever, chills, sweating, headache, nausea, body aches, diarrhea, vomiting, breathing issues, and chest pain. However, if these symptoms worsen, then it may cause jaundice, or the patient can slip into a coma.

6. Japanese Encephalitis

Adults can experience fever, headache, and vomiting at the early stage of the disease. However, after a few days, neurological disorders, fatigue, and movement issues can develop. Children usually face seizures, and about 20-30% of adults who suffer brain infections face death.

7. West Nile Fever

Common symptoms like fever, headache, fatigue, body aches, nausea, enlarged lymph glands, and skin rashes (in some cases) are experienced by the patients. About 1 in 150 cases report severe symptoms like neck stiffness, coma, tremors, and paralysis.

8. Plague

It usually affects the lymph nodes, causing inflammation, pain, and accumulation of pus in the sores. If this infection spreads to the lungs, it can cause pneumonic plague, which causes shortness of breath, chest pain, cough, and in some cases, bloody sputum.

9. Typhus

It is characterized by high fever, headache, chills, coughing, severe muscle aches, and fatigue.

There is no specific treatment for vector-borne diseases. They can only be managed through medicines and antibiotics that help kill or prevent the bacteria's growth. If the symptoms worsen, then the patient has to be hospitalized.

Thus, it is essential to note early symptoms and immediately contact a healthcare provider. Based on clinical evaluation, lab tests, and exposure history, the doctor can confirm the diagnosis and start treatment without delay.