Mosquitoes. An insect so tiny yet incredibly deadly, causing over 1 million reported deaths per year.
Only the female mosquitoes actually suck blood from warm-blooded mammals. Male mosquitoes feed mostly on nectar or honeydew instead. Female mosquitoes bite mammals as blood contains the protein which is necessary for i synthesising eggs, before they are laid in stagnant water for reproduction.
The Mosquitoes themselves do not naturally carry disease. It is the manner of transmission that enables infection of many diseases found in the blood of warm-blooded animals such as dengue, and more recently, the Zika virus.
These are the common and potentially life-threatening diseases that can be spread by mosquitoes:
1. Dengue
One of the most common diseases spread by mosquitoes in tropical climates. This disease is carried and spread primarily by mosquitoes in the genus Aedes . Common symptoms of the dengue virus are:
- Back and joint pain and discomfort
- Fever (often 40C or higher)
- Rashes
- Eye pain
2. Yellow fever
Like dengue, this disease is spread primarily by mosquitoes in the Aedes genus, and more specifically the Aedes aegypti dubbed as the "yellow fever mosquito". The yellow fever virus has approximately 3 to 6 days of incubation period from the time of transmission before it shows symptoms which are:
- Fever
- Chills
- Headache
- Nausea (dizziness)
In some cases, re-occurrences is possible and accompanied by more serious symptoms, including:
- Vomiting with blood
- Abdominal discomfort and pain
- Nosebleeds
3. Zika virus
One of the recent diseases spread by mosquitoes, the Zika virus is a mosquito-borne disease which was first identified in Africa in 1947 and named after the Zika forest. During the recent outbreak, the first reported case was in Brazil in 2015.
Symptoms of the Zika virus are:
- Slight fever
- Rash
- Joint pain
- Conjunctivitis
These symptoms, however, are mild and about 80% of the people infected will not even be aware that they are infected.
However, this disease can cause a rare birth defect called microcephaly, a neurological disorder that results in babies being born with abnormally small heads and developmental issues, to women who are pregnant whilst infected with the Zika virus.
4. Malaria
Caused by parasites, namely the Plasmodium vivax or Plasmodium falciparum which develops in a female Anopheles mosquito for approximately 10 to 18 days and is then transmitted when feeding.
After infection, these parasites migrate to the liver and eventually the bloodstream where they will continue to multiply and damage the red blood cells as they do so.
Symptoms of Malaria include:
- Fever
- Sweating
- Headaches
- Chills
5. Chikungunya
A disease also spread by mosquitoes in the Aedes genus, namely the Aedes aegypti and Aedes albopictus. Incubation of Chikungunya is usually 3 to 7 days and symptoms include:
- Sudden fever
- Chills
- Headache
- Nausea
- Vomiting
- Rash
- Lower back pain
- -Joint pain