As the weather is becoming cooler & winter is near, the number of mosquitoes is increasing rapidly. Mosquitoes are small, that look like flies, constitute the family Culicidae. Females of most species are ectoparasites, whose tube-like mouth parts pierce the host’s skin to consume blood leading to red bumps on the skin that causes itching.
Dengue is one of the disease that is caused by mosquitoes. It is said that malaria spreads the most in winters because the number of mosquitoes is highest at that time. But dengue does not wait for winters, in fact it is likely to spend the most in the rainy season. As the dengue mosquito lays its egg in water filled containers or places where there is enough water. The dengue larvae spreads the most in areas where water is found. Moreover, the dengue virus bearing mosquito can fly up to 400 meters finding water, to lay its egg. The peak biting periods of dengue mosquitoes are early in the morning & in the evening before the dusk.
Dengue (Deng-gey) Fever also known as Break-bone Fever is a mosquito-borne disease that occurs in tropical & subtropical areas of the world which causes flu, cough, cold, high fever, rash & muscle and joint pain. A severe form of dengue fever is also called Dengue Hemorrhagic Fever which can cause severe bleeding, a sudden drop in blood pressure (shock) & death.
According to the local media, 10,000 dengue cases were reported in year 2015, in Pakistan. Out of which 9899 cases were registered, including 7 fatalities during the course of year. Other than this, in the past 50 years the incidence of dengue worldwide has increased 30 folds.
CAUSATIVE ORGANISM: There are 4 different type of viruses that cause dengue fever but the most common is “Aedes aegypti” which is a female mosquito.
SIGN & SYMPTOMS
A symptom is something the patient feels or reports, while a sign is something that other people, including the doctor detects. A headache may be an example of a symptom, while a rash may be an example of a sign.
These are divided into 3 categories:
- Mild Dengue Fever
- Dengue Hemorrhagic Fever (DHF)
- Dengue Shock Syndrome
MILD DENGUE FEVER: Symptoms can appear up to 7 days after the mosquito carrying the virus bites & usually disappear after a week. This form of the disease hardly ever results in serious or fatal complications.
The symptoms of mild dengue fever are:
- Aching (painful) muscles & joints
- Body rash that can disappear & then reappear
- High fever
- Intense headache
- Pain behind the eyes
- Vomiting & feeling nauseous
DENGUE HEMORRHAGIC FEVER (DHF): Symptoms during onset may be mild, but gradually worsen after a number of days. DHF can result in death if not treated in time.
Mild dengue fever symptoms may occur in DHF, as well as the ones listed below:
- Bleeding from mouth/gums
- Clammy skin (Pale Coloured Skin)
- Considerably damaged lymph and blood vessels
- Internal bleeding, which can result in black vomiting & stool
- Lower number of platelets in blood (Platelets are the cells that help clot your blood)
- Sensitive stomach
- Small blood spots under your skin
- Weak pulse
DENGUE SHOCK SYNDROME: It is the worst form of dengue which can also result in death, again mild dengue fever symptoms may appear, but others likely to appear are:
- Intense Stomach Pain
- Disorientation (Lack of Concentration)
- Sudden Hypotension (Fast Drop in Blood Pressure)
- Heavy Bleeding
- Regular Vomiting
- Blood Vessels leaking Fluid
Dengue fever is diagnosed by a medical care giver by the relatively characteristic sequence of high fever, rash appearance & other symptoms in a person who has a history of recent travel to dengue endemic areas (place where the disease is more common) & recalls mosquito bites while in the endemic area. However, if not all of the symptoms are present or the history is not complete, the care giver is likely to run a number of tests to obtain a definitive diagnosis.
BLOOD SAMPLE: This sample can be tested in a laboratory in a number of ways to find signs of the dengue virus. If the dengue virus is detected diagnosis is straightforward; if this fails there are other blood tests which can identify antibodies, antigens & nucleic acids, including:
- ELISA (enzyme-linked immunosorbent assay)
- HI assay (hem agglutination inhibition assay)
- RT-PCR (reverse transcriptase-polymerase chain reaction)
There is no specific medicine to treat dengue infection. If you think you may have dengue fever, you should use pain relievers & avoid medicines such as aspirin, which could worsen bleeding. You should also rest, drink plenty of fluids to get hydrated & see your doctor as soon as possible. If you start to feel worse in the first 24 hours after your fever goes down, you should get to a hospital immediately to be checked for complications.
If you have severe dengue fever, you may need:
- Supportive care in a hospital
- Intravenous (IV) fluid & Electrolyte replacement
- Blood pressure monitoring
- Transfusion to replace blood loss
COMPLICATIONS (IF NOT TREATED)
The complications of dengue fever are usually associated with the more severe forms of dengue fever; hemorrhagic & shock syndrome. The most serious complications, although infrequent, are as follows:
- Hemorrhage (Bleeding)
- Low platelets
- Hypo-tension (Low blood pressure)
- Bradycardia (Slow heart rate)
- Liver damage
- Neurological damage (Seizures, Encephalitis)
- High fever
- Damage to the lymphatic system
- Damage to blood vessels
- Bleeding from the nose
- Bleeding from the gums
- Liver enlargement
- Circulatory system failure
There are currently no vaccines for dengue fever. The best way to prevent the disease is to avoid being bitten by mosquitoes altogether. Although there is no certain treatment for dengue, it can be treated as long as it is caught before developing into dengue shock syndrome or dengue hemorrhagic fever.
There is no vaccine to prevent dengue fever. The best way to prevent the disease is to prevent bites by infected mosquitoes, particularly if you are living in or traveling to a tropical area. This involves protecting yourself & doing efforts to keep the mosquito population down.
TO PROTECT YOURSELF
- Stay away from areas that have water nearby.
- Use mosquito repellent. Permethrin can be applied to your clothing, shoes & bed netting. You can also buy clothing made with permethrin already in it. For your skin, use a repellent containing at least a 10% concentration of DEET.
- When outdoors, wear long-sleeved shirts & long pants.
- When indoors, have net doors & mosquito killers installed.
- Make sure window & door screens are secure & free of holes or unnecessary opening. If sleeping areas are not screened, use mosquito nets.
- If you have symptoms of dengue, immediately speak to your doctor.
- To reduce the mosquito population, get rid of the places where mosquitoes can breed. These include plantation/flower pots, bird & pet’s water dishes, open areas, water storage, etc.
FEW KEY POINTS TO KNOW IF YOU HAVE DENGUE FEVER
- High Grade fever (104°F)
- Chills, Headache, Pain under the eyes & Body ache
- Appearance of Rash (Spots on body).
- Bradycardia (Decrease Heart Rate)
- Hypo-tension (Low Blood Pressure)If you are feeling these signs and symptoms then you must approach to your health care provider.
MODE OF INFECTION