Dengue fever has created havoc in the big cities of Punjab causing mass number of cases and casualties. According to the WHO report on dengue situation 2011, "a total of 9,451 cases and 45 deaths due to dengue infection, with a Case Fatality Rate (CFR) of 0.47 percent were reported so far. In 2010, a total of 7,403 cases and 19 deaths, with a CFR of 0.26 percent were reported during the same reported time." The outbreak of dengue fever pandemic in Punjab is an alarming state for more provinces as well.
Origin: These days People are cautious to know the background and history of this epidemic virus. Historians believe that dengue virus and its carrier mosquito have their origin from Africa. This species is thought to have made its way out of Africa on slave ships during the 17th, 18th and 19th centuries. By 1800, it spread in many large tropical cities, especially those with very active shipping ports. The mosquito population remained stable in these areas for many years before experiencing a growth explosion during and after World War II. Tropical and sub-tropical regions such as South and Central America, Southeast Asia, Sub-Saharan Africa, and Indonesia are favourite places of the mosquitoes. Dengue fever is estimated by the WHO to cause about 50-100 million infections per year world-wide.
In Pakistan, The first case of dengue fever reported in 1994 since then the disease makes its appearance mostly after raining season because open reservoirs of water provide the mosquito suitable atmosphere for propagation. According to the International Society for Infectious Diseases (ISID), the number of people hospitalised with dengue fever has increased by more than 25 percent in 2011, as compared with last year 2010 in Pakistan, especially in the province of Punjab. The world-wide incidence is estimated to be 50 to 100 million cases of dengue fever (DF) and several hundred thousand cases of dengue hemorrhagic fever (DHF) per year.
The vector mosquito: Dengue fever (DF) and dengue hemorrhagic fever (DHF) is a mosquito-borne disease. The mosquito "Aedes Aegyptis" that causes dengue fever appears as a new terrorist of the year 2011. This mosquito can be easily distinguished as it is larger with black and white stripes on her body, so it sometimes called tiger mosquito. It usually feeds on blood, as it requires the blood protein to produce its eggs. Body odor and carbon dioxide attract it. Mosquito carrying dengue virus bites during the day at 6 am-9 am and 4pm -10pm. It usually breeds from July until October, When temperature falls below 22 degrees centigrade, the growth of the aedes aegypti mosquito stops and consequently, the dengue season ends.
Types: There are two types of dengue fever, classical and haemorrhagic. In the Classical Dengue Fever, the mortality rate is very low. A severe, flu-like illness affects infants, young children and adults. The Hemorrhagic fever or 'Shock Syndrome' is the severe variety, which could be incurable. Most often death becomes inevitable and occurs within 24 hours, especially among children. This type of fever is fatal in 5% of those affected.
World Health organization's description of the DHF is as follows, "It is a potentially deadly complication, characterised by high fever, hemorrhagic phenomena, often with enlargement of the liver and in severe cases, circulatory failure. The illness commonly begins with a sudden rise in temperature accompanied by facial flush."
Signs and symptoms: The symptoms and signs for dengue begin about five to seven days after a mosquito bites and transfers a virus to a person. Fever and painful muscle and joint aches can occur during the first few hours of symptoms when headache, chills, rash, and swollen lymph nodes first appear. Pain behind the eyes is also a common symptom. These symptoms usually last about two to four days and then diminish, only to reappear again with a rash that covers the body and spares the face. The rash also may occur on the palms of the hands and the bottom of the feet. The symptoms may last about one to two weeks with complete recovery, in most cases, in a few weeks. The patients eventually develop severe abdominal pain, heavy bleeding, and blood pressure drops; this syndrome, if not treated quickly, may cause death. WHO warned that "immediately consult your physician if any of the following manifestations appear:
Red spots or points on the skin; bleeding from the nose or gums; frequent vomiting; vomiting with blood; black stools; sleepiness; constant crying; abdominal pain; excessive thirst (dry mouth); pale, cold or clammy skin; or difficulty in breathing."
Spread: Dengue fever is a seasonal disease with peaks during monsoon season. It should keep in mind that dengue fever is not a contagious disease, which means there is no human-to-human dengue fever transmission. The normal cycle of dengue infection is human - mosquito - human.
The viral disease transmitted by mosquitoes badly affects humans. The dengue viruses are usually present in the patient's blood before the start of symptoms, and remain for an average of five days after the illness. When the female Aedes Aegyptis mosquito bites dengue-infected person, the dengue virus infects her. For about a week the virus multiplies inside the mosquito, after which it bites a healthy person, who soon develops symptoms of dengue once a mosquito is infected; it remains infected for its life span.
The viruses belong to the Flaviviridae family and have an RNA strand as its genetic makeup. Virologists term them dengue virus types 1-4 (DENV 1-4). All four serotypes are closely related. However, there are enough antigenic differences between them that if a person becomes resistant to one serotype, the person can still be infected by the other three serotypes. This year all four types of viruses attacked in Pakistan.
Prevention and care: There should be appropriate measures to control the breeding of the mosquitoes. WHO forbid giving the patient Aspirin or Ibuprofen and recommending giving large amounts of fluids (water, soups, milk and juices) along with the patient's normal diet.
Points to prevent mosquito breeding: The mosquito grows in clean water, in garden and fresh water reservoir such as swimming pools. Water accumulates in broken bottles and tins, flowerpots, coconut shell, and tree holes etc are favourite places of its breeding. Tyers for swimming purpose likely to carry mosquito eggs because swimming pools are suitable places for mosquito breeding. Eggs of mosquito also found stuck on washed vehicle tyres.
Never let water uncovered in buckets, cooler and tubs, cover them at all times. Treatment: So far, there are no specific anti-viral tablets or injections that can kill the virus. However, a lot of supportive care and treatment can go a long way to save the patient.
According to a news report, The World Health Organisation (WHO) has approved new clinical management guidelines for dengue diagnosis and treatment for Pakistan. The new guidelines recommend a 'simple diagnostic tool' in the form of Tourniquet test, which requires just a simple blood pressure to differentiate between seriously ill and uncomplicated cases of dengue fever. There is no need to undergo a variety of clinical investigations for every suspected dengue fever patient as witnessed at public and private health facilities during the current wave of dengue virus. In the Tourniquet test, a physician will apply the blood pressure cuff on the upper arm of dengue suspected patient and inflate the bulb to 90 millimeter of mercury. The purpose is to apply pressure to see blood spots on forearm of the patient. After a period of five minutes, the physician will calculate the number of petechiae in squire inch on the forearm. If in this one inch the number of spots is more than 10 then the patient certainly will require hospitalisation.
Healthcare experts emphasise, "To prevent the infection of dengue virus, social awareness and control of mosquitoes is the foremost. The environment should be clean, water tanks, containers should be covered, and mosquito nets should be used. If there is any fever, immediately consult qualified doctors, if required get hospitalised either in a clinic or hospital for proper observation and treatment."