Dengue An Epidemiological Approach Biology Essay

In this universe there are many little unseeable animals which affect worlds in many ways. These include viruses, bacteriums etc. Among these animals, some have mercilessly claimed the lives of 1000000s. One such being is dengue virus that has been bring downing world since clip immemorial. Dengue is making headlines presents in the media. The mayhem it is making is immense. Harmonizing to WHO ( 2009 ) , 50 million dandy fever infections occur yearly and about 2.5 billion people live in dengue endemic states. Globally dengue epidemics are known to happen over the back-to-back last three centuries in tropical, semitropical and temperate countries ( WHO, 2011 ) . Furthermore, Park ( 2009 ) proposes that dandy fever has become one of the prima causes of deceases in Asia. Furthermore, Nathan, Drager and Guzman ( 2009 ) reference that dandy fever imposes important wellness, economic and societal load on the populations of endemic countries. Furthermore, literature suggests that people are less cognizant of disease indicants taking to detain in medical aid. Itrat et Al. ( 2008 ) besides found reduced consciousness about dandy fever among Pakistani people. Sing lay waste toing effects of dandy fever in many states every bit good as in Pakistan, this paper attempts to discourse prevalence, causes, natural history, bar, direction and recommendations with respects to dengue.

Sapir and Schimmer ( 2005 ) define dandy fever as the “ most of import arthropod-borne viral disease of public wellness significance ” ( p.1 ) . From an epidemiological point of view, dandy fever is considered to be most quickly distributing disease with 30 creases increased incidences in last 50 old ages ( Khan and Hassan, 2011 ) . Harmonizing to WHO ( 2002 ) , two-fifths of universe population are at hazard of dandy fever and yearly 500,000 instances of dandy fever hemorrhagic febrility and mortality rate of 2.5 % are reported. During the period from 2000 to 2006, approximately 545,000 instances were reported in 44 states ( Gomez-Dantes & A ; Willoquet, 2009 ) .

Dengue is now endemic in more than 100 states in Africa, America, Eastern Mediterranean, Southeast Asia and Western Pacific parts ( Burattini et al. , 2007 ) . Furthermore, Jahan ( 2011 ) asserts that pandemic of dandy fever began in Southeast Asia after World War II and spread worldwide. Another study estimates 12,000 dandy fever related deceases in Southeast Asia, 4,000 in Western-Pacific and 2,000 in America in 2002 ( WHO, 2004 ) .

Over the last few old ages, dandy fever instances in Pakistan have besides been increased. Khan and Hassan ( 2011 ) indicate that Pakistan has experienced a figure of dandy fever febrility eruptions since 1992 and in 2005. In October 2010, Ministry of Health Government of Pakistan reported a sum of 1500 dandy fever instances including 15 deceases due to complications ( Riaz, 2011 ) . Harmonizing to Idrees & A ; Ashfaq ( 2012 ) , dengue instances are observed throughout the twelvemonth in Pakistan with peak incidences in station monsoon period. They added that 2007 and 2011 have been the worst old ages for Pakistan because of inundations increasing dandy fever incidences. Furthermore, Pakistan National Health Department confirms more than 5,050 instances in the twelvemonth 2010 ( Yusuf, 2011 ) . These statistics show that there is high prevalence of dandy fever instances non merely in Pakistan but besides worldwide.

All infective diseases including dandy fever can be explained on the footing of epidemiological three that is host, agent and environment. Sajid, Ikram & A ; Ahmed ( 2012 ) explain that the agent in this three is dengue virus ( DEN ) which is a “ little single-stranded encapsulated RNA virus, ” comprises of four different serotypes ( DEN1 to 4 ) belonging to the genus Flavivirus. Since dandy fever is an infective disease and is specifically caused by DEN virus, there is a natural cosmopolitan susceptibleness to infection for all who are exposed to dengue ( Gomez-Dantes & A ; Willoquet, 2009 ) . This fulfills the Bradford Hill standards and Henle-Koch ‘s posits. The virus itself can non infect worlds through incursion instead it needs a vector Aedes aegypti mosquito to do disease ( Jahan, 2011 ) . Furthermore, Nathan et Al. ( 2009 ) assert that this mosquito is tropical and semitropical coinage chiefly a daytime feeder busying human habitation including H2O containers, non-recyclable merchandises ( plastic, metal and glass containers, tyres ) , rainwater reservoirs, hapless lodging conditions and deficient H2O and sewerage systems ( Jahan, 2011 ) . This vector and its home ground signifier the environmental constituent of this three. In add-on, worlds are considered to be preferred host of dandy fever virus. There are certain host factors that predispose a individual to infection. Harmonizing to Dinh et Al. ( 2012 ) , one hazard factor is age associated with badness. They assert that kids are more likely to see plasma escape and terrible signifiers of dandy fever i.e. dandy fever hemorrhagic febrility and dandy fever daze syndrome ( DHF/DSS ) than grownups while shed blooding and organ disfunction are more common in grownups. Gender is another factor but non so important. Gender based exposure varies among parts. Barney ( 2008 ) suggests that adult females are at higher hazard as most adult females work at places, increasing contact with house-dwelling and biting by vector increasing transmittal hazard. Furthermore, dandy fever is found to be associated with fluctuations in genesA PLCE1A andA MICB which encode a protein organizing the immune antiviral response ( Dinh et al. , 2012 ) . Additionally, low socioeconomic position is besides an of import factor. Higher rates of dandy fever are associated with husbandmans and people with low income and instruction degree ( Phuong et al. , 2008 ) . Furthermore, deficiency of street drainage and refuse aggregation trucks after heavy rain facilitates vector spread ( Barney, 2008 ) .

This agent-host-environment three plays a cardinal function in dengue transmittal. Shepherd ( 2012 ) elaborates that when mosquitoes suck an septic individual ‘s blood, they get the virus. Surveies have shown that septic individuals can convey virus every bit early as 2 yearss before symptoms develop. After come ining the mosquito, virus requires 8-12 yearss incubation before conveying to a non-infected individual ( Teo, Ng & A ; Lam, 2009 ) . Besides human-vector-human transmittal, perpendicular or intrapartum transmittal is besides reported increasing foetal mortality hazards ( SirinavinA et al. , 2004 ) . Transmissions through needle stick hurt, blood transfusion and organ organ transplant in rare instances are besides found ( ChuangA et al. , 2008 ) .

Once the virus is transmitted, it follows certain phases termed as natural history of disease. It starts with susceptibleness phase including certain hazard factors which predispose people to dengue as mentioned earlier. Next is subclinical phase. Harmonizing to Nathan et Al. ( 2009 ) , largely dengue infections are symptomless and its incubation period is 4-10 yearss in worlds. Pathogenesis of dandy fever in this phase is associated with the host immune response activated by dandy fever virus ( Stephenson, 2005 ) . When the virus enters human organic structure, it binds to WBCs and replicates. WBCs respond through innate immune system by bring forthing signaling proteins ( interferons and cytokines ) . Interferon stimulates antibodies and T-cells production. Major viral reproduction citations are monocyte-macrophage line of descent cells but other tissues such as liver, bone marrow, encephalon, pancreas and bosom are besides infected in terrible dandy fever ensuing in organ disfunction due to leakage from blood vass ensuing in hypovolaemia and hypo-perfusion. Bone marrow disfunction leads to thrombocytopenia increasing shed blooding inclinations.

The 3rd phase is clinical disease comprising of febrile and critical stages ( Nathan et al. , 2009 ) . Febrile stage stopping points for 2-7 yearss and is characterized by sudden high class febrility along with facial flushing, erythema, generalized unease, leucopenia and enlarged liver. Whereas in critical stage bead in temperature, addition in capillary permeableness and haematocrit degrees and haemorrhagic manifestations occur due to vasoactive go-betweens ( Jahan, 2011 ) . The last phase is recovery, disablement or decease. If clients survive 24-48 hours critical stage, a gradual extravascular fluid resorption occurs in 48-72 hours and general well-being improves with haemodynamic stableness. With proper direction dandy fever can be cured but if non managed decently, can take to DHF/DSS.

The load of all diseases can be reduced through bar. Likewise, dandy fever can besides be prevented by taking some steps. Among all degrees of bars, aboriginal comes foremost. It includes consciousness on mass degree through media and runs ( Queensland Dengue Management Plan, 2011 ) . Primary bar depends on vector control or break of human-vector contact. Preventive steps can be done for vector control through controlled sanitation, appropriate piped H2O supply, riddance of dead H2O, spraying and fumigation restricting mosquito genteelness points ( BMJ Evidence Centre, 2012 ) . Gomez-Dantes & A ; Willoquet ( 2009 ) suggest insect powders as unuseful because mosquitoes breed once more within two hebdomads even with its multiple applications. Furthermore, using door screens, casement blinds and domestic H2O bud vase covers, covering bare skin countries, utilizing mosquito cyberspaces and cringles at high hazard countries and waterproofing of Windowss are besides effectual ( Itrat et al. , 2008 ) . Therefore, increasing consciousness plans are important as they have a broad public wellness impact ( Rothman, 2010 ) . In this respect, community and public wellness nurses play a critical function.

Many septic persons remain symptomless doing dandy fever to be endemic. Therefore, early sensing and intervention are really of import which constitute secondary bar. Probes including CBC, LFTs and Anti dandy fever antibodies can be carried out ( Sajid, Ikram & A ; Ahmed, 2012 ) . When dandy fever is diagnosed, primary direction is to guarantee equal fluid intake dwelling of unwritten rehydration fluid, coconut H2O, fruit juices and soup instead than kick H2O. Furthermore, diagnostic intervention is done with antibiotics and febrifuges. Furthermore, complications are prevented throughfurther probes. Doctor should be consulted if febrility does non settle, intolerance to fluid, terrible abdominal hurting, addition hemorrhage and anuresis for more than 6 hours. Blood probe consequences should be reviewed every bit early as possible as a hold can quickly take to DHF/DSS ( Health Ministry Srilanka, 2010 ) .

Surveies suggest primary attention suppliers are more disease focused and demo small concern on public wellness positions hence, they need to be involved in dandy fever control and bar ( Ang, Rohani & A ; Look, 2010 ) . Following recommendations and schemes can be implemented. First, the vector needs to be controlled. All the favourable genteelness topographic points require pest control operators for regular monitoring. It besides helped Singapore to command dandy fever where they made pest control operators at all building sites, schools and houses ( Teng, 2001 ) . On the contrary, it might be impractical in Pakistan because of high costs so it is recommended that authorities should place dandy fever sensitive countries and educate the people for primary bar. Furthermore, specific vector control Torahs can be made to restrict disease transmittal. Boo ( 2001 ) mentioned about the Control Vectors and Pesticides ( CVPA ) statute law made by Singapore Government, harmonizing to which no 1 is allowed to make conditions favourable for the vectors. Second, effectual disease and vector surveillance systems can be established based on dependable research lab and wellness information ( WHO, 2011 ) . Since dandy fever is endemic in Pakistan, so changeless monitoring can be helpful to forestall sudden eruptions. Furthermore, it is besides suggested that people in the community should be educated about dandy fever control and bar through consciousness plans and proviso of enlightening booklets at their doorsills. This might be hard in Pakistan because of security issues therefore media can play a cardinal function in educating people through wellness related plans. Education will diminish dandy fever incidences and badness. In the 2011 eruption, Punjab Government opened a hotline calledA Punjab Health Line Project for Dengue to ease consciousness of marks and symptoms, supply aid and finally place susceptible countries. Such work is appreciable but a consistence needs to be maintained. In add-on, people can besides be involved in bar and control intercessions. This will construct community partnerships therefore doing the plans more effectual and sustainable by advancing autonomy and a sense of control over their ain wellness ( WHO, 2011 ) . Furthermore, consistent environmental schemes such as bettering H2O supply and storage systems, pull offing solid waste and frequent street cleansing in the state can cut down dengue transmittal and spread. ( McCall, Lloyd and Nathan, 2009 ) . For this, community and public wellness nurses require to place environmental factors through proper appraisal ( Gomez-Dantes & A ; Willoquet, 2009 ) . Last, research countries can be improved. A tetravalent vaccinum is presently being developed and may be available in the hereafter ( WHO, 2012 ) . Likewise, researches can be done and methods can be devised to place and handle dandy fever on a really primary degree.

In decision, dandy fever instances are found globally and are a cause of societal and economic load. It is a catching disease caused by DEN virus via mosquitoes. However, execution of comprehensive, effectual and incorporate preventative schemes will cut down incidences of dandy fever among populations globally. Early sensing is possible through profound consciousness easing diagnosing and intervention. Auxiliary researches are critical as presently the intervention of dandy fever is merely diagnostic. Since dandy fever is epidemic, so effectual partnerships at national, regional and planetary degrees can take to sustainable bar and dandy fever obliteration.