Dengue and Dengue and Vector Behaviour in
Contents
1. 12 13 14 15 16 17 18 19 REVISTA DE SALUD PUBLICA Volumen 7 1 Marzo 2005 REFERENCES Mera C Garcia I Velandia M Bernal M Cedefio D Serna MT et al Sistema de vigilancia sindr mica sobre enfermedades febriles transmitidas por vectores con nfasis en fiebre amarilla dengue y malaria en los departamentos de Guaviare Putumayo Caquet y Norte de Santander 2002 Inf Qinc Epidem Nac 2003 8 5 74 83 S nchez JF Las jornadas departamentales una estrategia fundamental para la pre venci n y control del dengue Bolet n Epidemiol gico de Cundinamarca 2002 3 1 55 65 Lwanga S Lemeshow S Determinaci n del tama o de las muestras en los estu dios sanitarios WHO 1991 p 65 Suarez MF Nelson MJ Registro de altitud del Aedes aegypti en Colombia Bio m dica 1981 1 4 225 Tauil P Urbanization and dengue ecology Cad Sa de P blica 2001 17 99 102 Gaviria AM Estudio seroepidemiol gico y de conocimientos actitudes y pr cticas sobre control y prevenci n del dengue Colegio Mayor de Antioquia 1998 Informe Quincenal Epidemiol gica Nacional 1999 4 15 226 229 Farieta S Estudio de identificaci n de reas cr ticas del dengue en funci n del riesgo epidemiol gica en el municipalidad de Girardot Madrid Facultad de Ciencias Universidad de Barcelona 2002 Espinoza F Hern ndez C Rend n R Transmisi n nterepid mica del dengue en la ciudad de Colima M x2. relative humidity was observed during daylight captures and temperature ranged from 21 C to 34 C There was 82 to 100 humidity during the nights this value coinciding with hours of rainfall and temperature ranging from 17 C to 26 C Adults captured by using the landing on humans method both intra and peri domicilium were Culex sp Aedes aegypti were only captured at rest The bite per hour rate was 4 adults per hour for Culex being registered in the peridomicilium from 18 00 19 00 and 21 00 22 00 Sentry monitoring of febrile cases 83 cases of fever compatible with dengue were studied 59 of them were women minimum age was 5 years maximum being 85 average 29 7 years old 95 CI 26 3 33 34 9 of patients had been beyond C queza during the last 10 days n 29 Endemic epidemic sites for dengue which they had been to were Villavicencio Restrepo Cartagena Carmen de Apical Guayabetal Melgar Ibagu Girardot and Vichada The most representative site was Villavicencio which 12 residents had been to as tourists and for business 10 REVISTA DE SALUD P BLICA e Volumen 7 1 Marzo 2005 The main signs and symptoms reported by patients in the sentry monitor ing process were fever 100 headache 95 1 bodily pain 87 9 and exanthema 83 1 Two patients proved positive for IgM 2 4 The first aged 42 had not been beyond C queza during the 10 days before onset of symptomatology Ig M had been taken
3. for symptoms compatible with dengue and who had been living in dengue en demic areas during the 10 days prior to consultation Defining a febrile case This would have been a patient who had consulted as he she had presented temperature greater than or equal to 38 C having at least 5 days evolution and having lived for more than 10 days in the area plus the following signs and symptoms General chills photophobia prostration discomfort and diaphoresis Osteo muscular arthralgia and myalgia Gastrointestinal nausea vomiting anorexia diarrhoea and abdominal pain and Hemorrhagic haematemesis epistaxis ecchymosis haemoptysis melena Samples were taken for IgM if the above conditions were complied with Inclusion criteria The following criteria were taken into account Patients being aged more than 5 fulfilling case criteria Presenting probable signs and symptoms of dengue and Wishing to participate in sentry monitoring Exclusion criteria The following criteria were taken into account Oral temperature less than 38 C Having a febrile picture with more than 3 weeks evolution Being aged less than 5 Visible causes of another infectious disease tonsillitis acute respira tory infection media otitis etc and The lack of authorisation by the patient or person consulting hospital services for a blood sample to be taken 6 REVISTA DE SALUD P BLICA e Volumen 7 1 Marzo 2005 Land
4. 8 days after the onset of symptoms The other case aged 33 had also not been outside the town during the previous 10 days The sample had been taken 5 days after onset of symptoms Both cases stated that they had visited Villavicencio three months previously however they only referred to having had recent symptoms of dengue leading to them con sulting sentry monitoring DISCUSSION Studies carried out in Colombia during the last 25 years have corroborated finding the vector above 1 600 masl as has happened in Fusagasug Cundi namarca lying at 1 728 masl and M laga Santander at 2 200 masl 4 This means that the presence of the Aedes aegypti vector in the municipality of C queza 1 741 masl shows that this mosquito has been becoming adapted to altitudes greater than 1 500 masl during recent years Public and private means of transportation accelerated processes of urbanisation and man s in tervention are amongst the main causes of the vector s propagation and dis tribution 5 The level of dengue s seroprevalence 23 3 and the vector s high in festation rate suggest that dengue has been transmitted in C queza this added to the fact of being a town attracting the tourist trade makes the risk of inter epidemic transmission become high Seroprevalence levels found in Caqueza were lower then those found in Girardot 289 masl i e 89 6 On the other hand they were slightly higher than those found in Medellin 1
5. Two of the febrile patients n 83 were IgM positive Conclusions The study showed that dengue s urban vector can reach dan gerous levels of infestation above 1 700 masl however a deeper study of its bionomy is needed at these heights above sea level during different times of the year for improving knowledge regarding climatic and environmental fac tors affecting their efficiency as vector in these conditions Key Words Aedes aegypti seroprevalence sentinel surveillance entomology indicators Colombia source MeSH NLM RESUMEN Comportamiento del dengue y del vector en Caqueza Colombia 2004 2 REVISTA DE SALUD P BLICA e Volumen 7 1 Marzo 2005 Objetivo Describir el comportamiento del dengue y su vector en C queza Colombia 1 746 msnm mediante vigilancia serol gica entomol gica y vi rol gica entre Marzo y Junio de 2004 M todos Se realizaron dos tipos de estudio Un estudio de corte transversal para la vigilancia serol gica poblacional y el levantamiento de los indicado res entomol gicos donde los participantes fueron seleccionados de la pobla ci n general por muestreo aleatorio de conglomerados El segundo estudio fue de vigilancia centinela sobre casos febriles sospechosos de dengue du rante cuatro semanas incluyendo el comportamiento del vector tasa de pi cadura y horas de actividad mediante la t cnica de aterrizaje sobre el humano Durante el mismo periodo se realiz una jornada de aseo lo que permit
6. from 17 389 cases in 1997 to 81 831 in 2002 The same behaviour has been observed for hemorrhagic dengue less than 5 000 in 1998 to 5 500 cases in 2002 1 Behaviour for the Cundina marca department has similarly increased rising from 800 cases of classical dengue in 2000 to 2 161 in 2003 There has also been an important occur rence of 150 and 300 cases of hemorrhagic dengue per year between 2001 and 2003 2 Rodriguez Dengue Vector 3 Various dengue epidemics have occurred since 1970 following re infesta tion by Aedes aegypti in Colombia with the four serotypes circulating throughout the country These four dengue serotypes are currently circulating throughout Colombia though not having the same intensity The dengue 2 vi rus was isolated in 1971 and has been circulating since then with dengue 1 Dengue 4 began to circulate in 1984 and has continued to circulate since then to date Dengue 3 circulated for a short period during the mid 1970s disap pearing for several years and reappearing in the Santander department in 2001 1 The main vector of dengue in Colombia is Aedes aegypti 1ts dissemina tion being limited by altitude It has been found in Colombia at altitudes of up to 2 200 metres above sea level masl where annual temperature is 17 C This altitude is higher than the maximum internationally reported in India 2 121 masl In spite of it being known that it can exist at these altitudes its behaviour is not well kn
7. 538 masl i e 16 3 7 Seroprevalence has been found to be 33 in Colima M xico 490 masl 8 The high percentage of inhabitants engaging in unsuitable practices for controlling dengue must be stressed Inhabitants in 75 of households were used to hoarding a lot of waste items cans bottles jar pots tyres to not cleaning low deposits suitably and leaving them open uncovered thus making both aspects into the main risk factors for Aedes aegypti proliferation Reservoirs and tyres represent the best larval habitat whilst bedrooms are adult mosquitoes preferred habitat 9 Rodriguez Dengue Vector 11 Other sectors of the municipality such as municipal educational centres the hospital and cemetery aid the vector s growth and proliferation due to the presence of elements flower vases jar pots tyres containing stagnant water for long periods of time Areas in Rio de Janeiro Brazil have remained posi tive for Aedes aegypti such as scholastic concentrations and other places due to their immediate environmental conditions being predisposed towards ovi posture 10 Another important aspect in the spread of the vector s presence to sur rounding rural areas is due to their closeness to the urban area allowing Aedes aegypti to travel to these neighbouring territories This vector s dispersion by flight is very limited when compared to other mosquito species 100 metre flight dispersion is considered rare but it has
8. Rev Salud p blica 7 1 1 15 2005 ART CULOS INVESTIGACI N Dengue and Dengue and Vector Behaviour in C queza Colombia 2004 HERN N RODR GUEZ G and FERNANDO DE LA HOZ R Received on 30 November 2004 Reviewed on 6 December 2004 Accepted 4 February 2005 ABSTRACT Objective Describing the behaviour of dengue and its vector in C queza Colombia 1 746 masl by serological entomological and virological monitor ing between March and June 2004 Methods Two types of study were carried out One was a cross sectional study for serologically monitoring the population and taking entomological in dicators participants were selected from the general population by random conglomerate sampling The second study consisted of monitoring febrile cases suspected of dengue during a four week period Vector behaviour bite rate and hours of activity was also included by using the landing on humans technique a rubbish collecting day was run during the same period for evaluating this intervention s short term effectiveness Results Total prevalence of infection by dengue IgG positive was 23 3 in 252 people examined in the surveyed population Household infestation in dex was 32 9 deposit index was 8 4 and Breteau index was 43 9 Fol lowing the rubbish collection day the infestation index became reduced by 56 14 5 post intervention deposit index by 43 4 8 post interven tion and Breteau index by 59 17 9 post intervention
9. been shown that a pregnant fe male can fly up to 3 km to deposit her eggs 11 One of the study s strengths was that 83 of samples collected during the five months spent collecting larvae corresponded to Aedes aegypti this fact shows the VBD assistants level of training which contributed towards con structing the indexes One of this study s important limitations was revealed by scant adult Aedes aegypti captures by the landing on humans method for determining their behaviour and bionomy Captures were also made at rest contrasting with collecting adult Culex sp which was much greater using the same tech nique Capturing mosquitoes when they alight on humans and bite them represents a sensitive means of detecting low level infestations but requires a lot of personnel Both male and female Aedes aegypti mosquitoes are at tracted to human beings and bearing in mind that males present low disper sion indexes their presence could thus be a trustworthy indicator of the proximity of hidden breeding places The rubbish collection day and mass awareness raising campaign to gether with training and prevention activities run with the community an im portant reduction was shown in most households infestation indexes even more so when these activities were concentrated in higher risk deposits The 3 entomological indexes ostensibly became reduced by between 43 and 59 low deposits positivity percentages importantly diminished po
10. i evaluar la efectividad a corto plazo de esta intervenci n Resultados La prevalencia total de infecci n por dengue IgG positivos fue de 23 3 en 252 personas examinadas en la encuesta poblacional El n dice de infestaci n de viviendas fue de 32 9 el ndice de dep sito fue de 8 4 y el de Bretau de 43 9 Despu s de la jornada de aseo el ndice de infestaci n se redujo en un 56 14 5 post intervenci n el de dep sito disminuy en un 43 4 8 post intervenci n y el de Bretau en un 59 17 9 post intervenci n Entre los pacientes febriles n 83 dos fueron posi tivos para IgM Conclusiones El estudio sugiere que aunque hay presencia del vector la transmisi n interepid mica de dengue es baja en esta poblaci n Con res pecto al vector es importante porque hay pocos estudios del comportamiento del dengue en poblaciones por encima de 1 500 metros en Latinoam rica Palabras Clave Aedes aegypti seroprevalencia vigilancia centinela indi cadores entomol g a Colombia fuente DeCS BIREME pending on the year from 250 000 to 500 000 cases of hemorrhagic den gue occur each year around the world Average yearly lethality rate is around 5 and most cases of death caused by dengue occur amongst children and young adults has been calculated that 50 to 100 million cases of dengue and that de The incidence of classical dengue in Colombia since 1978 has fluctuated having a tendency to increase rising
11. ico Salud P blica de M xico 2003 45 5 365 370 Tinker M Olano V Ecolog a del Aedes aegypti en un pueblo de Colombia Sur Am rica Biom dica 1993 13 1 5 14 Reinaldo Souza R S Carvalho M Spatial analysis of Aedes aegypti larval distri bution in the Ilha do Governador neighborhood of Rio de Janeiro Brazil Cad Sa de P blica 2000 16 1 31 42 Dengue y dengue hemorr gico en las Am ricas Gu as para su prevenci n y con trol OPS 1995 Publicaci n Cient fica N 548 p 3 34 Camacho T De la Hoz F C rdenas V S nchez C De Calder n L P rez L et al Vigilancia epidemiol gica incompleta de la epidemia de Dengue 2 en Iba gu Colombia Biom dica 2004 24 2 174 182 Lloyd L Mejores pr cticas para la prevenci n y el control del dengue en las Am ricas USAID February 2003 Acha P Cipr s B Zoonosis y enfermedades transmisibles comunes al hombre y a los animales OPS 1997 Publicaci n Cient fica N 503 p 302 305 Guzm n M Kouri G Dengue an update The Lancet 2002 2 33 42 Biolog a y control del Aedes aegypti Center for Disease Control Vector topics 1980 4 1 80 Benenson A Manual de control de las enfermedades transmisibles en el hombre D cimo quinta edici n OPS Publicaci n cient fica N 538 1992 p 82 88 Suarez M Aedes albopictus Skuse Diptera culicidae en Buenaventura Co lombia Inf Qinc Epidem Nac 2001 6 15 222 223 Cuzzubo A Vaughn D Nisalak A Solomon T Kala
12. ing on humans technique The vector s bionomy was also studied bearing in mind its behaviour hours of peak activity bite rate etc Conditions for collecting sending and trans porting samples to the Cundinamarca Public Health Laboratory strictly ad hered to the protocol established by the Laboratory s Entomology Unit The format for remitting samples was similarly filled in specifying the date of capture place gender collector s name and identification on the collecting flask coinciding with the date of having been sent to the laboratory Adult mosquitoes which had been collected were killed with cold ciga rette smoke and then carefully packed in plastic boxes to be sent to the public health laboratory to be read by the entomologist careful packing was stressed for ensuring that basic structures were not lost for later taxonomic identification 6 visits were made to the town accompanied by a VBD assistant having experience in this activity 4 nights were spent in the following sites from 6 pm to 6 am Hospital San Rafael de C queza the Departmental gardens and two private houses Time was spent in the two following places during the day from 8 am to 6 pm Hospital San Rafael de C queza and the Departmental gardens Sample taking Random serum sampling only 1 inhabitant per household was done for the seroprevalence survey anti dengue IgG for a total of 253 samples Those people were identified who had had symptoms compa
13. l monitoring Aedes indexes were constructed on two occasions An initial one was taken for determining housing deposit and Breteau percentages Another index was taken later helped by the mayor s office following a rubbish collection day This was done after making the community aware of the need for collecting waste items washing reservoirs covering deposits etc The vector born dis ease VBD helper and or entomologist evaluated the different low deposits reservoirs drums buckets or other recipients and high deposits where the inhabitants kept their water covered or uncovered water tanks as well as diverse deposits where water collected such as cans tyres jar pots bottles plants etc The following indicators were analysed Housing index larval positive houses inspected houses x 100 Deposit index positive deposits inspected deposits x 100 and Breteau index positive deposits inspected houses x 100 houses inspected Rodriguez Dengue Vector 5 Sentry serological monitoring in patients having a clinical picture compatible with dengue This was done for 4 weeks between June and July by processing 24 pa tients samples per week Sample screening was calculated with 95 reli ability for detecting 30 prevalence assuming that at least 3 were positive 3 The reference population consisted of people residing in C queza s urban area consulting San Rafael hospital s outpatient services sentry centre
14. lity of being infected by dengue 8 REVISTA DE SALUD P BLICA e Volumen 7 1 Marzo 2005 Pre rubbish collection day entomological monitoring Total larval index per block was 32 9 95 CI 31 02 35 0 ranging from 0 to 66 6 30 mean Total deposit index was 8 3 95 CI 9 0 10 4 ranging from 0 to 24 2 8 6 mean Total Breteau index was 43 2 95 CIZ40 2 46 2 ranging from 0 to 100 42 8 mean Table 1 shows how positive a breeding place was according to type of breeding place Being positive was higher in lower tanks 28 pre rubbish collecting day than the most numerous breeding place following it An im portant reduction could be observed in being positive in lower tanks post rubbish collecting day whilst no reduction took place in other types of breeding place on the contrary being positive increased in some cases Table 1 Positivity of Aedes aegypti breeding places Pre and post rubbish collection day C queza Cundinamarca 2004 Observed Infested positive Type ee Pre rubbish POstrubbish Prerubbish Postrubbish Prerubbish Postrubbish place collecting day collecting collecting collecting collecting collecting g day day day day day day High tanks 164 251 3 0 1 8 0 0 Low tanks 301 348 84 32 27 9 9 1 Tyres 38 32 1 5 2 6 15 7 Plants 278 45 6 3 2 1 6 7 Different places 646 428 24 9 3 7 2 1 Total 1427 1104 118 49 8 2 4 4 Bottles jar pots tins waste items Post rubbish collection day en
15. om the urban area and 10 households were chosen from each town block during a second stage The urban map of C queza had to be modified as the most up to date had been drawn up in 1998 and it was seen that the number of houses per block had increased A cadastral engineer was enlisted to help in redesigning the cartographic plans Once the changes had been made and bearing the forgoing in mind the map was then divided into sec tors then successively into barrios blocks and houses The percentage of houses per block was very unequal in some cases respecting other blocks for example one block had 10 houses whilst most had between 24 30 houses The foregoing meant that blocks having such a low number of houses were grouped for levelling them out with the others 35 conglomerates were finally left 30 blocks and the households within each block were chosen to be stud ied by using a list of random numbers generated by Epitable software EPI INFO 6 04 A total of 274 houses was visited an average of 8 houses per block 36 houses could not be surveyed because they were closed or because the inhabitants did not wish to be visited The most used variables in the serological survey were block age gen der completed years of schooling social security travelling outside C qu eza using mosquito netting the main symptoms of dengue previous diagno sis Of dengue sample taking and Ig G result Pre and post rubbish collection day entomologica
16. own above 1 500 metres The current investigation was carried out to elucidate dengue epidemiological behaviour and that of its vector in C queza in the Cundina marca department lying at 1 746 masl where the vector was found for the first time in 2003 however no information regarding the virus autochtho nous circulation has been available to date Data collected during this study could help in elucidating the behaviour of dengue and its vector at high alti tude MATERIALS AND METHODS Study site C queza is a town having a population of 21 000 inhabitants 63 of them living in the municipality s urban area Its average temperature is 21 C It is situated near several municipalities which have reported autochthonous den gue in the past Types of study A cross sectional study was carried out for serological monitoring of the population and taking entomological indicators A serological sentry moni toring system was set up for determining the incidence of dengue in patients presenting the disease s acute symptoms The short term effectiveness of a rubbish collecting day was also determined by recording entomological in dexes following the intervention Sampling methods for the entomological and serological survey 4 REVISTA DE SALUD P BLICA e Volumen 7 1 Marzo 2005 Multistage conglomerate sampling was done for determining seropreva lence and entomological indicators 30 conglomerates were thus randomly selected fr
17. pective analysis Serologically monitoring the population 75 6 95 CI 70 3 80 7 of the total of 253 people surveyed were fe male Ages ranged from 6 to 85 u 39 6 years old 95 CI 37 4 41 8 38 of the people were affiliated to the subsidised health insurance regime n 101 37 8 were affiliated to their contributory regime n 99 and 23 n 60 were not affiliated to the Colombian General Social Security in Health System The average of years spent living in the town was 27 4 95 CI 24 9 29 9 ranging from 1 to 82 years 66 of the people had been outside the town during the last year n 173 Only 7 9 of the population surveyed used a mosquito net when sleeping n 20 There was 23 3 95 CI 18 28 n 59 prevalence of infection caused by dengue IgG positive whilst 28 8 of those positive for Ig G had had symptoms of dengue during the last year 95 CI 17 9 42 8 It was found that the p value was not statistically significant for either bivariable or multivariable analysis when measuring association between being infected by dengue and some independent variables such as travelling or not having been outside C queza using or not using a mosquito net hav ing or not having had symptoms of dengue and prevalence of dengue per block The exception was the last independent variable OR 1 06 95 CI 1 04 1 07 p lt 0 001 i e having other people infected on a town block was significantly related to the probabi
18. pture of adults according to time and place C queza Cundinamarca 2004 Date of Aedes aegypti Culex sp capture Time Place Site Type of capture Emale Mala Male Female 06 04 04 20 21 Private household Study Intra domicilium human bait 1 1 06 04 04 21 22 Private household Study Intra domicilium human bait 3 3 06 04 04 4 5 Private household Bedroom At rest 4 07 04 04 5 6 Private household Bedroom At rest 3 14 04 04 18 19 Departmental gardens Bathroom At rest 1 2 21 04 04 21 22 Departmental gardens Living room Intra domicilium human bait 1 1 21 04 04 22 23 Departmental garden Bathroom At rest 2 2 22 04 04 1 2 Departmental garden Living room Intra domicilium human bait 2 22 04 04 4 5 Departmental garden Bathroom At rest 3 22 04 04 6 7 Departmental gardens Bathroom At rest 1 04 05 04 12 13 Hospital Car park Intra domicilium human bait 1 1 11 05 04 18 19 Hospital Outpatient Intra domicilium human bait 1 1 11 05 04 21 22 Hospital Outpatient Intra domicilium human bait 1 11 05 04 23 24 Hospital Car park Intra domicilium human bait 1 12 05 04 4 5 Hospital Outpatient Intra domicilium human bait 1 20 05 04 12 13 Colegio Santiago Bathroom At rest 2 3 Guti rrez 20 05 04 14 15 Colegio Santiago Bathroom At rest 4 1 2 Guti rrez 08 06 04 19 20 House particular Corridor Intra domicilium human bait 2 08 06 04 20 21 House particular Corridor Intra domicilium human bait 1 Total 7 6 17 22 13 14 W nun 00 9 10 1
19. st rubbish collecting day As sentry monitoring for IgM finding low sero reactivity was only car ried out for four weeks this represented another limitation This leads to it being thought that this type of monitoring should be done periodically four 12 REVISTA DE SALUD P BLICA e Volumen 7 1 Marzo 2005 monthly together with virological monitoring which could not be carried out in this study to be alert to the imminence of an outbreak of dengue Even though the latter type of monitoring is essential it has been demonstrated that viral isolation is minimal when epidemics happen 12 This study has shown that dengue s urban vector can reach dangerous infestation levels in places lying above 1 700 masl However its bionomy must be studied more deeply at these altitudes during different times of the year for improving knowledge regarding climatic and environmental factors affecting its efficiency as a vector in such conditions e Acknowledgements We would like to thank A Victor Olano from the Instituto Na cional de Salud the people working in the Cundinamarca Public Health Laboratory especially Pilar Carrillo and F lix Ruiz the Tecnosuma Laboratory especially Le n Dovale Dur n and Patricia Mu oz health workers in Hospital San Rafael de C queza the Mayor s office in C queza VBD assistants William Le n and every one else who has helped in carrying out this study Rodriguez Dengue Vector Table 3 Type of ca
20. tible with dengue dur ing the last year A serum sample was taken on day 6 and then on from cases having had an acute febrile clinical picture sentry monitoring during the last 10 days for processing them for anti dengue IgM giving a total of 83 pa tients Written informed consent was always asked and given for both types of monitoring when collecting and processing samples The following recommendations were taken into account 7 10 ml blood was obtained and placed in a sterile tube without anticoagulant Samples were then left to coagulate at room temperature for a period of at least 30 minutes and not more than 2 hours until coagulum became com pletely retracted Rodriguez Dengue Vector 7 Samples were then centrifuged at 3 000 rpm for 20 minutes and Serum samples were finally put into duly labelled name and date sample was taken sterile screw topped tubes in aseptic conditions Sample conservation and transport Samples were sent as soon as possible in refrigerated conditions to the Cundinamarca Public Health Laboratory where they were processed by the bacteriologist responsible for this area using Tecnosuma kits Each batch of samples was accompanied by its respective laboratory order RESULTS Data was collected using instruments designed for such purpose Survey population data such as that for the sentry population was loaded using Epi Info software version 3 2 2 and then exported to SPSS version 12 for re s
21. tomological monitoring Total larval index was 14 5 95 CI 10 8 19 1 ranging from 0 to 44 4 11 1 mean There was 56 reduction respecting pre rubbish col lecting day indexes Total deposit index was 4 8 95 CI 3 5 6 2 ranging from 0 to 28 4 6 mean There was a 43 reduction following the rubbish collecting day Total Breteau index was 16 7 95 CI 12 8 21 6 ranging from 0 to 63 6 12 5 mean There was 59 reduction respecting pre rubbish collecting day indexes Rodriguez Dengue Vector 9 Table 2 shows distribution by gender and specie of larvae captured be tween February 2004 and August 2005 It can be seen that Aedes aegypti was the most frequently identified gender followed by Culex quinquefasciatus Least captures were made during June Table 2 Specie and genus of larvae captured per month Caqueza Cundinamarca 2004 Month Aedes Aedes Culex Culex Culex Linatus Anopheles aegypti fluviatilis _quinquefasciatus _coronator sp durhami _argyritarsis February 10 0 0 0 0 0 0 April 509 1 13 1 29 1 0 May 142 0 37 1 0 0 8 June 0 1 8 41 3 0 0 August 114 10 8 0 1 0 0 Total 775 12 66 43 33 1 8 83 1 2 7 4 6 3 5 0 1 0 8 Rate of landing on humans Table 3 shows the places times date and type of capture of adult male and female Aedes aegypti and Culex Sp Aedes aegypti never circulated at night captures coincided with daylight hours and dusk as one would expect with this vector 62 to 90
22. yanarooj S Aaskov J et al Comparison of panbio dengue duo IgM and IgG capture ELISA and venture Rodriguez Dengue Vector 15 technologies dengue Ig M and IgG dor blot Journal of clinical virology 2000 16 135 144 20 Mancheno M Kroeger A Alvarez G Manual t cnico para el control de malaria dengue leishmaniosis y oncocercosis Editorial Servi offset 2000 p 81 98 21 Giraldo GP Cuevas H Pab n JD Padilla JC Comportamiento del dengue cl sico asociado con la temperatura superficial del mar como indicador del ci clo ENOS en Colombia 1980 1998 Informe Quincenal Epidemiol gica Nacional 1999 4 21 322 327
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