A Case Study of Dengue Disease Transmission by Aedes Aegypti Mosquito from Kanyakumari District Using Stochastic Eco- Epidemiological Model
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JASC: Journal of Applied Science and Computations ISSN NO: 1076-5131 A case study of dengue disease transmission by Aedes aegypti mosquito from Kanyakumari District using stochastic eco- epidemiological model P.S.STEM EDILBER Dr. R.SUBRAMONIAM Dr.K.L.M PRASAD Research Scholar Asst.prof Asst.prof H.H.The Rajah’s college Lekshmipuram college of Arts and science H.H.The |Rajah’s College [email protected] Neyoor Kanyakumari District [email protected] ABSTRACT: We present a stochastic dynamical model for the transmission of dengue that takes into account seasonal and spatial dynamics of the vector Aedes aegypti. It describes disease dynamics triggered by the arrival of infected people in a city. We show that the probability of an epidemic outbreak depends on seasonal variation in temperature and on the availability of breeding sites. We also show that the arrival date of an infected human in a susceptible population dramatically affects the distribution of the final size of epidemics and that early outbreaks have a low probability. Mostly the disease affecting during the month of june, july august in Kanyakumari district. A brief study was taken regarding this Aedes aegypti affected people in 4 taluk in Kanyakumari district. BRIEF HISTORY OF KANYAKUMARI: Kanyakumari district is the southernmost district in Tamil Nadu State and mainland India. It is the second largest district in the state in terms of population density and the second most urbanized, next only to Chennai district. The district derives its name from the devi Kanya Kumari Amman, who is enshrined in the temple located in Kanyakumari town. The district stands first in terms of literacy rate in the state. The district headquarters in Nagercoil. Kanyakumari district has a varied topography with sea on three sides and the mountains of the Western Ghats bordering the northern side. Geologically, the landmass of the district is much younger when compared to the rest of state – faulted as late as 2.5 million years during the Miocene, after which numerous stransgression as well as regression of sea had shaped the western coast of the district. Historically, Nanjinad and Eda which comprise the present Kanyakumari district, were ruled by various Tamil and Malayalam dynasties: the Venad Kingdom, Pandyans, the Cheras, the Cholas, the Ays and the Nayaks. A few artifacts unearthed by archeological excavations in there. It was part of the princely state of Travancore during the colonial times prior to India’s independence; four of the eight tehsils of Thriuvanthapuram district were separated to form the new district of Kanyakumari during the formation of the new state of Kerala, and they were made a part of the Madras Presidency under recommendations from the States Reorganisation Commission in 1956. The Presidency was later renamed Tamil Nadu and Kanyakumari, today is one of the 32 districts of Tamil Nadu state. Volume 5, Issue 11, November/2018 Page No:1362 JASC: Journal of Applied Science and Computations ISSN NO: 1076-5131 No.of.Revenue Sl. Name of the Name of Taluk No. of Firka Villages No. Division 1 Agastheeswaram 4 43 1. Nagercoil 2 Thovalai 3 24 3 Kalkulam 6 66 2. Padmanabhapuram 4 Vilavancode 5 55 Total 18 188 POPULATION In Kanyakumari District the population is 1,870,374 on Male - 9,26,345 Female - 9,44,029 IRRIGATION Kannyakumari District is receiving fairly good rain fall from both South West and North East monsoons. Major Rivers: Thamirabarani, locally known as Kuzhithuari river. The river has two major distributors namely Kodayar and Paraliayar, Pazhyar is also a major river and other small rivers are Valliyar, Pamborivaikel, Ulakkapuviar, Thadaviyar. SOILS In this vast area come under, Utisol in between Nagercoil and Kaliyakkavilai. The Utisol are heavily leached soils, Reddish and Yellowish in colour. Low organic matter content low Nitrogen, Phosphoures and Pottash. These soils are acidit (P.H. 6.0) in soil reaction cation exchange capacity in low and phosphate fixation is high. Alfisoils are observed in cultivate tracts agastheeswaram and Thovalai, weathered granite is main pacent material. These soils are low in organic matter almost neutal P.H. (6.5 to 7.5) low to medium status of Nitrogen content. Volume 5, Issue 11, November/2018 Page No:1363 JASC: Journal of Applied Science and Computations ISSN NO: 1076-5131 Major crops Paddy - I season 20,00 H.a - II season 20,000 Pulses - 4,000H.a Tapioca - 9,000H.a Banana - 4,000H.a Coconut - 21,100H.a Rubber - 19,475H.a Fruits & Vegetables - 7,500H.a CLIMATE AND RAINFAL This District is having favorable Agro climatic condition so as to grow a number of crops. Even though the district is small it can accommodate various food and non-food crops, growing under different agro climate conditions. Because of its being bearer to equivator, its topography and other climatic factors, favour the growth of varied crops. The general climate of the District is pleasant. Both the south west monsoon and North East monsoon influence the climate of the region besides the proximity of the sea and dwindling heights of the western ghats. The normal rain in the districts is 1443 M.M. KEYWORDS: Mortality of eggs: meg, hatching rate: elr, mortality of larvae :mla, density- dependent mortality of larvae: ∝ pupation rate :lpr, mortality of pupae :mpu, pupae into adults development coefficient :par and emergence factor : ef ;ma: mortality of adults, cycle1: gonotrophic cycle coefficient (number of daily cycles) for adult females in stages NA1; 풐풗풓(풊,풋): oviposition rate by flyers in the (i,j) patch egn: average number of eggs laid in an oviposition. cycle 2: gonotrophic cycle coefficient (number of daily cycles) for adult females in stage LA2; ahv: transmission probability from host to vector; avh: transmission probability from vector to host; EIP: extrinsic incubation period. Event type effects on the sub-populations and transition rates for developmental model. The coefficients are mh: human morality coefficient; VP: human viremic period ; IIP: intrinisic incubation period . 1. INTRODUCTION Arboviruses is a shortened name given to arthropod-borne viruses from various families which are transmitted by arthropods. Some Arboviruses are able to cause re-emergent Volume 5, Issue 11, November/2018 Page No:1364 JASC: Journal of Applied Science and Computations ISSN NO: 1076-5131 diseases such as St. Louis Encephalitis, Chikungunya, Dengue, Ross River disease, West Nile, Yellow Fever, Equine Encephalitis, etc.. Arthropods are able to transmit the virus upon biting the host, allowing the virus to enter the host’s bloodstream. The virus replicates in the vector but usually does not harm it. In the mosquito-borne diseases, the virus establishes a persistent infection in the mosquito salivary glands and there is sufficient virus in the saliva to infect another host during feeding. Each arbovirus usually grows only in a limited number of mosquito species. The work presented in this article is focused on mosquito-borne diseases (mainly dengue fever) transmitted by Aedes aegypti. This is one of the most efficient mosquito vectors for arboviruses, because it is highly anthropophilic, thrives in close proximity to humans and often lives indoors. Dengue is spread only by adult females, which require blood to complete oogenesis. During the blood meal the female ingests dengue viruses from an infectious human. The viruses develop within the mosquito and are re-injected in later blood meals into the blood stream of susceptible humans. Dengue is an acute febrile viral disease (with four serotypes of flavi viruses DEN1; DEN2; DEN3 and DEN4) which presents headaches, bone, joint and muscular pains, rash and leukopenia as symptoms. Dengue epidemics were reported throughout the 19th and 20th centuries in the Americas, southern Europe, northern Africa, the eastern Mediterranean, Asia, Australia and on various islands in the Indian Ocean, Central Pacific and Caribbean [1]. The history of dengue in Argentina began as early as in 1916 when an epidemic affected the cities of Concordia and Paraná. In 1947 the Pan American Health Organization (PHO) led a continental mosquito eradication program and by 1967 the mosquito was considered to be eradicated in Argentina. The mosquito was detected again in 1986 and since 1997 several epidemic outbreaks took place in the northwestern and northeastern regions of the country. In India he first epidemic of clinical dengue-like illness was recorded in Madras in 1780 and the first virologically proved epidemic of dengue fever (DF) occurred in Calcutta (now Kolkata) and Eastern Coast of India in 1963-1964. In Tamil Nadu dengue has been rampant in the last two decades. Dengue is usually considered as a problem of urban areas, but reports indicate its emergency in rural also. The prevalence of dengue vector and silent circulation of dengue virus have been detected in rural and urban Tamil Nadu which is increasing. During the academic year 2016-2107 a sudden rise in febrile cases was reported in all government and private hospital in Kanyakumari district. The patient presented with fever of 7-10 days duration accompanied by headache and vomiting. As the clinical samples were found negative for malaria and enteric fever, dengue was suspected. In order to determine the aetiology of fever in this outbreak a rapid seroepidemiological investigation was carried out. Now a days A.aegypti is a permant inhabitant in Kanyakumari district. Every summer there is a potential risk of dengue virus transmission because of arrival of viremic people from Kerala. However no autochthonous cases of the disease have been detected until present but in the last years some clinical studies confirmed dengue infection in people arriving from neighbouring endemic countries. Therefore the development of mathematical models Volume 5, Issue 11, November/2018 Page No:1365 JASC: Journal of Applied Science and Computations ISSN NO: 1076-5131 which permit the estimation of the probability of an epidemic outbreak and its final size has become a matter of sanitary necessity.