The recent outbreak of Dengue Fever in parts of Lahore/Punjab has very rightly raised concern amongst certain quarters of the society about the disease. It is important to understand the disease, its nature and work on its preventive measures.
Dengue Fever & Dengue Hemorrhagic Fever
- Dengue is a serious viral disease transmitted by the bite of the mosquito, Aedes aegypti.
- Dengue occurs in two forms: dengue fever and dengue haemorrhagic fever.
- Dengue fever is a severe, flu-like illness that affects older children and adults but rarely causes death.
- Dengue hemorrhagic fever (DHF) is a second more severe form, in which bleeding and occasionally shock occur, leading to death; it is most serious in children.
- Dengue hemorrhagic fever is a deadly disease and early diagnosis and treatment can save lives. Unless proper treatment is given promptly, the patient may go into shock and die.
People with weakened immune systems, as well as those with a second or subsequent dengue infection, are believed to be at greater risk for developing dengue hemorrhagic fever.
Dengue viruses are transmitted to humans through the bites of infective female Aedes mosquitoes.
Mosquitoes generally acquire the virus while feeding on the blood of an infected person.
After virus incubation (development inside mosquito) for 8-10 days, an infected mosquito is capable, during probing and blood feeding, of transmitting the virus, to susceptible individuals for the rest of its life.
Warmer weather, preferably between temperatures of 25 to 30 degrees Celsius enables the female Aedes mosquito, the carrier/vector of dengue fever, to mature faster and reproduce rapidly.
The virus circulates in the blood of infected humans for 2 to 7 days, at approximately the same time as they have fever; Aedes mosquitoes may acquire the virus when they feed on an individual during this period.
Symptoms, which usually begin four to six days after infection and last for up to 10 days, may include
- a sudden, high fever
- severe headaches pain behind the eyes
- severe joint and muscle pain
- skin rash, which appears three to four days after the onset of fever
- mild bleeding (such a nose bleed, bleeding gums, or easy bruising)
Sometimes symptoms are mild and can be mistaken for those of the flu or another viral infection. Younger children and people who have never had the infection before tend to have milder cases than older children and adults. However, serious problems can also develop. These include dengue hemorrhagic fever, a rare complication characterized by high fever, damage to lymph and blood vessels, bleeding from the nose and gums, enlargement of the liver, and failure of the circulatory system. The symptoms may progress to massive bleeding, shock, and death. This is called dengue shock syndrome (DSS).
Prevention of Dengue Fever
A. aegypti is a domestic mosquito which lives intimately with its human hosts. These mosquitoes breed primarily in man-made containers such as water storage containers, old tires and flower vases in and around human dwellings. Elimination of these breeding sites is an effective and definitive method of controlling the mosquito and therefore of preventing transmission of dengue.
According to world Health Organization, the only way to prevent the dengue is to combat the vector mosquitoes.
- Steps for vector control should be initiated through community based programs, using environmental management and chemical methods, proper solid waste disposal and improved water storage practices.
- Apply insect repellent containing DEET (e.g. the locally available “Mospel” brand) to exposed skin when outdoors. Strictly follow the directions on the product’s label, so as to determine the recommended frequency and quantity of its application.
- When outdoors, always wear long-sleeves, long pants and socks. Treating clothes with repellents containing permethrin or DEET will give extra protection, since mosquitoes may bite through thin clothing.
- The hours from dusk to dawn are peak mosquito biting times. Consider avoiding outdoor activities during these times. If this is not possible, then take extra care to use repellent and protective clothing as per the advice.
- Residences should, whenever possible, have mosquito nets fitted in all doors, windows, and ventilation outlets.
- As mosquitoes lay eggs in standing water, limit the number of places around your home where they might possibly breed, including open water tanks, fountains, birdbaths, buckets, water barrels, cans, and natural patches.
- Homeowners are urged to keep their pails and other containers overturned, change water in bowls and vases daily, and keep flowerpot plates dry to deter mosquito breeding.
- Apartment and flat dwellers who have plants outside their homes, in balconies, should take measures to prevent water from stagnating in the flower plates, containers, pots, watering cans, and other surfaces below the potted plant display racks.
- Herbal substances like ‘Harmal’ are considered effective mosquito repellants.
- Landed property owners, are reminded to clear leaves and silt that collect at roof gutters. They are encouraged to use insecticides which are useful for killing larvae, and to keep their gardens tidy.
- Containers such as ice cream tubs used for weeding, watering cans, pots, and other items should be kept dry and properly stored.
- Used tyres are a perfect breeding site for these mosquitoes. Ensure fumigation of sites containing old used tyres and other items where rain water usually collects. It is advisable to have garage and store fumigated.
- Kerosine oil and used motor oil are effective in culminating the mosquitoes in the larvae stage. The same can be sprayed in possible breeding sites at least twice a week.
- Aedes aegypti breeds primarily in man-made containers like earthenware jars, metal drums and concrete cisterns used for domestic water storage, as well as discarded plastic food containers, used auto mobile tyres and other items that collect rainwater.
- Occasionally the mosquito also breeds in natural habitats such as tree holes and leaf axils.
Treatment protocols for Dengue Fever
- Measure temperature of a patient who falls sick
- In case of persistent high fever (above 1000 F) get the CBC (Complete blood picture) done wherein Platelet count and WBC count is important
- Patients with reduced platelet and WBC counts are urged to get their counts checked every day
- Patients with reduced WBC count must wear mask to protect themselves from contracting other infections
- An infected patient must take 2 tablets paracetamol 4-6 times a day to control fever
- Patients must consume atleast 12-14 glasses of water every day
- Once the platelet count falls below 60,000, arrange a potential blood donor
- Once the platelet count falls below 25,000, contact a doctor/hospital and get the blood donor ready for blood transfusion and platelet extraction
- Patients who bleed must immediately report to a hospital/doctor
- Patients with bleeding disorders, contracting this disease must immediately report to a hospital/doctor