research article cockroach infestation and factors...

Hindawi Publishing CorporationInternational Journal of ZoologyVolume 2013, Article ID 649089, 6 pageshttp://dx.doi.org/10.1155/2013/649089

Research ArticleCockroach Infestation and Factors Affecting the Estimation ofCockroach Population in Urban Communities

Gholam Hossein Shahraki, Saadat Parhizkar, and Alireza Raygan Shirazi Nejad

Faculty of Health Science, Yasuj University of Medical Sciences, Yasuj, Iran

Correspondence should be addressed to Gholam Hossein Shahraki; [email protected]

Received 5 February 2013; Revised 21 April 2013; Accepted 22 April 2013

Academic Editor: Randy J. Nelson

Copyright © 2013 Gholam Hossein Shahraki et al. This is an open access article distributed under the Creative CommonsAttribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work isproperly cited.

Cockroach is one of the most important pests in urban communities. This study was conducted to determine the situation ofcockroach infestation and effective factors on cockroach trap count in urban communities of Yasuj City in southwestern Iran. Inthis study cockroach population in 573 sampling units (residential units, official places, and hospitals) was monitored using stickytraps over a five-week trapping period. Occupants of 348 residential units were also questioned (by means of questionnaire) forcockroach infestation in their respective residence.The study shows almost 39% of sampling units were infested by cockroach. Fivespecies from two families had been identified: Blattidae (comprising Blatta orientalis, B. lateralis, and Periplaneta americana) andBlattellidae (comprisingBlattella germanica and Supella longipalpa). German cockroach,B. germanica, withwidespread distribution(80% of infested sampling units) showed the highest frequency (96.7%) of trap counts.The expression of the distribution of Germancockroach populations and some factors could affect trapping, and population monitoring in an urban community was surveyed.Additionally, affecting some exclusion factors on cockroach infestation was pointed. Rates and source of cockroach infestation werediscussed from the viewpoints of the residents.

1. Introduction

Cockroaches have been in existence for about 360 millionyears [1], and they are one of the important groups of insectpests in urban environments. Cockroaches not only spoilfood but also transfer pathogens and cause allergic reactionsand psychological distress [2]. As a potential mechanicalvector of human diseases, many pathogenic organisms havebeen associated with cockroaches. These include poliomyeli-tis viruses, bacteria, fungi, protozoa, and helminthes [3–6]. Pai et al. [7] reported cockroaches as potential vectorsof nosocomial infections. Moreover, bacteria with antibioticresistance have been isolated from household cockroaches[8, 9]. The most common important species is associated tosurveyed locations. In the southeasternUnited States, smoky-brown cockroach [10], in New Zealand, German cockroach[11], and in Southeast Asia, American cockroach [12–16] werefound to be the most dominant species, respectively. Whilethe German cockroaches, Blattella germanica (L.), are notpresent in households in Southeast Asia, they are prevalent

insect pests in hotels and food outlets [17, 18]. There are over3,500 species of cockroaches worldwide. Of these only severalspecies are commonly associated with humans. Three domi-ciliary species of importance are the German cockroach, theAmerican cockroach (Periplaneta americana), and theOrien-tal cockroach (Blatta orientalis) [19]. German cockroach hasa worldwide distribution, although it originated in north ortropical Africa despite the misleading common name [20].However, German cockroach has created substantial pestproblems in many developing countries [21–24]. This speciesreported a common indoor pest in low-income housing [2].

According to the report by Hanafi-Bojd and Sadaghiani[25], there are 24 species of cockroaches from 4 families:Polyphagidae (12 species), Blattidae (5 species), Blattellidae (5species), and Ectobiidae (2 species), that have been identifiedthroughout the cities of Iran so far. Three species, the Ger-man cockroach, the American cockroach, and the Orientalcockroach, are the most common species that have causedhealth problems in urban communities (e.g., residentialbuildings, hotels, hospitals, restaurants, and shopping) of

2 International Journal of Zoology

Table 1: Surveyed locations and results of trap monitoring throughout the programme.

Type of location Number oflocations

Samplingunits

Size of units(limitation)

Infestedsampling units

Number of infestedunits with

B. germanica

Number of identifiedcockroaches (%)

Dormitories fromfour universities∗ 11 dormitories 386 12–18m2

× 2.5m 141 (37%) 116

5758 B. germanica (97.59%)91 B. lateralis (1.54%)

46 P. americana (0.78%)4 S. longipalpa (0.07%)1 B. orientalis (0.02%)

Hospital 2 hospitals 121 12–18m2× 3m 71 (59%) 60

1125 B. germanica (93.28%)62 B. lateralis (5.14%)19 P. americana (1.58%)

Housing complex 7 buildings 27 70m2× 2.5m 7 (26%) 5

131 B. germanica (94.93%)6 P. americana (4.35%)

1 Supella longipalpa (0.72%)Official place 1 building 22 12–14m2

× 3m 4 (18%) 0 5 B. lateralis (100%)Hotel 1 building 17 12–18m2

× 2.5m 2 (12%) 0 2 B. lateralis (100%)∗YUMS, YU, AU, and TU.

Iran. Additionally, Polyphaga indica, P. aegyptiaca, Periplan-eta australasiae, and Blatta lateralis are the other importantcockroaches in Iran.

Yasuj, which is situated in southwestern Iran and thecapital of Kohgiluyeh va Boyer Ahmad, was chosen for thisstudy.The province covers an area of 15,563 square kilometersand in 2006 had a population of 634,000 [26]. The weathervaries with seasons: cold and snowy in the winter, cold ormoderate and rainy in the spring and fall, and hot (not morethan 35∘C) and dry in the summer [27]. Mean annual tem-perature, rainfall, and humidity are 15∘C, 866mm, and 45%RH, respectively. Although ancient structures of housings arepredominant throughout the city, new structures of buildingshave sprung up in the last few years [27].

2. Materials and Methods

After a preliminary survey on private and public places inthe southwestern of Iran, Yasuj City, 573 sampling units wereselected for the study (using sticky trap), and a sampling unitcomprised an “apartment unit” for residential building and a“room” for hospital, dormitory, hotel, and government office(Table 1). At the inspection stage, monitoring was performedweekly using sticky traps for sampling units. Moreover 97private houses had been surveyed by questionnaire. Thesticky traps were manufactured by Ridsect (produced by SaraLee Sch. Bhd. Malaysia) in baited tent form, and the sizeof the sticky surface of the trap was 16 × 9 cm2. Dependingon the surveyed locations, traps were placed in cabinets,under the sink, beside the refrigerator, beside the stove, inclosets, and on shelves, with one side of the trap restingagainst a vertical surface. Average one trap per eight squaremeters was installed in sampling units. Totally the number ofcockroaches per trap for each sampling unit was estimated.Infestation rate is defined as cockroach trap count per trapduring seven-day trapping period. Numbers of cockroachestrapped were recorded weekly after each 7-day trappingperiod. The trapping process continued for a 5-week period.

A set of questionnaires were distributed for occupantsof the 348 residential units (from 10 dormitories, 97 privatehouses, and 7 house building complexes) to obtain infor-mation about cockroach infestation in their houses (e.g.,size of cockroach, time, and entrance-source of cockroachinfestation). Some details of the structural design (conjugatedto survival of cockroach) for 69 units of hospital werecollected by the other set of questionnaire.

Data was analyzed by Kruskal-Wallis Test and Spearmancorrelation coefficient besides descriptive statistics using theSPSS software.

3. Results and Discussion

From a total of 573 sampling units inspected using trapping(i.e., apartments, units, or housings), 39.3% (225 units) wereinfested with cockroaches.The results show that 37, 59, 26, 18,and 12% of the sampling units in the surveyed dormitories,hospitals, housing building complexes, official places, andhotel, respectively, were infested with cockroaches (Table 1).Therefore, the hospitals showed the highest frequency ofinfested units via trap monitoring. Plumbing facilities (i.e.,wash basin), heating source, and openings in the roof for84, 43.5, and 21% of units (𝑁 = 69 units) at the hospi-tals, respectively, obtained from the questionnaire, could bedetected as effective factors for survival of cockroach [28]which explained the high rate of infestation for the hospitals.A survey on 97 private houses throughout the city by meansof questionnaires showed that 80% of residences complainedof cockroach infestation.Therefore, survey by cockroach trapmonitoring showed that all surveyed locations (22 areas) inthis city were infested with cockroaches, although infestationrates varied throughout the urban communities.

From a total of 7251 cockroaches collected from 22different locations of the city, five species of cockroacheshad been identified. The German cockroach was the mostabundant comprising 96.73% of all cockroaches trapped.The other identified species in order of abundance were the

International Journal of Zoology 3

Turkestan cockroach (Blatta lateralis) (2.21%), the Americancockroach (0.98%), the Brown-banded cockroach (Supellalongipalpa) (0.07%), and the Oriental cockroach (0.01%).Therecognized species are from two families: Blattidae (compris-ing B. orientalis, B. lateralis, and P. americana) and Blattel-lidae (comprising B. germanica and S. longipalpa). Hanafi-Bojd and Sadaghiani [25] previously reported four familiesfrom indoor and outdoor survey (Polyphagidae, Blattidae,Blattellidae, and Ectobiidae). However three species, theGerman, American, and Oriental cockroaches were reportedas the most common species in Iran [25]. These species weredetected in this study, although the Turkestan cockroachinstead of the Oriental cockroach showed the third commonspecies (for frequency of distribution and dispersion). Per-centage frequency of the German cockroach in the five typesof study locations (Table 1) shows the German cockroachwas the most abundant in the dormitories (98%), housing(95%), and hospital (93%), respectively, compared to theother species. However, it was not seen in official places andhotels. Moreover, more than 80% of infested units (181 from225 units; Table 1) were infested by the German cockroach(i.e., the highest frequency of dispersion among infestedunits). Therefore, surveyed dormitories showed the mostdiverse composition with all five species present and themostabundant for the German cockroach compared to the otherstudy locations. Official places and hotels with the lowestinfested units (18 and 12%, resp.) revealed the least variedfor cockroach species and least abundant for the Germancockroaches. However,more official buildings and hotel unitsneed to be surveyed to substantiate the findings.

Sizeable German cockroach trap count was detectedfor four study locations (Table 2). The expression of thedistribution of German cockroach populations in space atfour locations based on the formula of the variance to meanratio ([𝜎2/𝜉 < 1] for uniform [𝜎2/𝜉 = 1] for random, and[𝜎2/𝜉 > 1] for clumped) [29] was clumped, although for thehospitals this ratiowas near to random (Table 2).This index isimportant because it is consistent from year to year for eachspecies [29]. The German cockroach is known as domesticcockroach and lives in groups (semisocial insect), and theyare rarely dispersed throughout a building [30, 31]. Thusclumpeddistribution for these species is expected. Cockroachinfestation rates for hospital and residential building showlower mean than girls’ and boys’ dormitories, although therewas no significant difference (𝑃 > 0.05) between meanof cockroach infestation rates for four surveyed locations(Kruskal-Wallis Test; chi-square = 1.352, d.f = 3, and 𝑃 =0.509).

Some factors affecting the estimating of cockroach pop-ulation in an urban community were surveyed. Survey oninfestation rates (German cockroach infestation) for the units(72 units at four locations) which were located on differentfloors showed the number of floors (i.e., distance of apart-ment from ground) did not significantly affect cockroach trapcounts (𝑟

𝑠= 0.118,𝑃 = 0.324).Moreover, there was no signif-

icant difference in cockroach infestation rates between floorsof these buildings (Kruskal-Wallis Test; chi-square = 7.636, d.f= 4, and 𝑃 = 0.106) (Table 3). Additionally the variance ofthe population was positively correlated with elevation of the

Table 2: Mean of cockroach trap counts for four study locations.

Studylocations

Number ofsurveyedunits

Frequencyof infested

units

Mean ofinfestation rate(per trap/unit)∗

Variance/mean ratio

Girls’dormitory 53 72% 15.90 18.75

Boys’dormitory 72 72% 16.96 34.87

Residentialbuilding 25 60% 7.73 7.39

Hospital 101 61% 4.02 1.36∗For infested units.

Table 3: Mean and variance of cockroach tap counts for surveyedfloors of four surveyed buildings (72 units).

Floor Mean N Std. deviation VarianceG 3.4450 4 1.07438 1.1541 11.8731 25 13.11264 171.9412 11.4316 29 15.25659 232.7633 10.1000 10 9.08811 82.5944 51.5000 4 46.56616 2168.407Total 13.1823 72 18.52862 343.310

floors (the highest floor with the biggest variance; Table 3),and this correlation was significant (𝑟

𝑠= 7, 𝑃

(1-tailed) =0.045). Paige [32] reported strong population fluctuation ofGerman cockroachwas negatively correlatedwith barometricpressure. It can be deduced that the higher the floors of abuilding, the greater the cockroach population fluctuations.These observations will be useful when conducting survey ofcockroach infestations in buildings withmore than five floorshigh or in skyline structures.

Eighty one percent of residents for three dormitories(comprising 116 units) said that their units were infestedby cockroaches, although 53% of those units were detectedas infested via cockroach trap monitoring. Actually resi-dents reported 28% higher infestations of units than thatdetermined from trap monitoring. This is probably dueto the low tolerance of a considerable number of respon-dents towards cockroach, prompting to a questionably highincidence of infestation. Moreover, sensitivity of trappingmethod for clean level of infestation could be influenced byfrequency of infestation, and those units with less than onecockroach per trap (nominated as clean level unit) reportedas infested instead. Brenner et al. [33] reported differentrates of cockroach prevalence for residential apartmentsfrom questionnaire and trapping. Agrawal and Tilak [34]reported more cockroach counts based on visual countsmethod compared to sticky trap method. However, the traps(baited with mouse pellets) were reported as a best way todetermine cockroach infestation [35–37]. Only 4% of theoccupants at the infested units did not notice any infestation.This could be attributed to these occupants being awayfrom home. Moreover, survey on 348 study units of privatehouses, dormitories, and housing complex via questionnairesshowed that residents for 72% of surveyed residential units


Table 4: Frequency of resident’s responses to four items of questionnaire.

Type of location Sampling units∗ Frequency ofold ancient

Pointed out toinfestation of their

units

Encountered Germancockroach size

(≤1.5 cm)

Pointed out to infestationinitiated from more than 6

months agoDormitories 228 0 (153/228) 67% (107/149) 72% (80/150) 53%Private houses 97 55 (57%) (78/97) 80% (45/77) 58% (52/75) 69%Housingcomplex 23 0 (20/23) 87% (10/18) 56% (11/18) 61%

Total 348 55 (16%) (251/348) 72% (162/245) 66% (143/243) 59%∗Unit or houses.

admitted to cockroach infestation in their houses (Table 4).Comparison of this rate and total infestation report viatrapping (39%) shows 33% reduction for clean level units (inagreement with previous report: 28% for the dormitories).Therefore, the determination of cockroach infested units ishighly associated to the type of cockroachmonitoring. Surveyon 19 house kitchens of the dormitories via two approaches(visual and trap counts) showed that cockroach had been seenimmediately once upon entry for 20% of infested kitchens.From 80% remaining kitchens, the cockroach had been seenvisually in 8% of these places when the trash containerwas moved. Survey via sticky trap resulted in 21% highlevels of infestation (≥26 cockroach per trap per kitchen)for the kitchens. This is close to the rate of visual survey(20%) even after moving the trash container (28%) in thekitchens. However, the greatest difference between methodsis observed for the determination of very low levels ofinfestation. It shows a limitation for exact determination ofinfested sampling units.

The other factor pointed as an effective factor on infes-tation is age of building. Only 16% of surveyed places wereconsidered old (≥10 years old). All of these places were in thecategories of private houses (Table 4). Surveys on the housesshowed 85% of old houses versus 73% of new houses (46versus 30 houses) were infested by cockroaches. Therefore,age of building could have an impact on infestation, althoughthe correlation between the two factors was not significantbased on 95%CI (𝑟

𝑠= 0.149,𝑃 = 0.150). Survey also showed

59% of infested units were infested more than six monthsprior to the survey (Table 2), suggesting infestation did notoccur spontaneously and transient in nature.

The other factors that could affect trapping (and/or pop-ulation monitoring) are attacks by other pests and damageto traps. Out of the 2113 inspection of cockroach traps inthe surveyed dormitories throughout the programme, 7.8% oftraps were found damaged. The most frequent cause of thesedamages (4.8%) was that the traps had been thrown out byresidents. Although a briefing for occupants to accept andcontribute to this programme led to reduction in trap dispo-sition, a number of respondents were not comfortable withthe image that their living or working place is infested withcockroaches.The incidences of damage by lizard (0.28%), ant(0.28%), andmice (0.24%)were low in this study, although forother countries, such as Malaysia, lizard (and also ant) couldbe the greatest cause of trap damages. Therefore incidence

Table 5: Frequency of screened fans at the surveyed kitchens.

Cockroach infestation No. of units (%) TotalFan without screen Screened fan

Clean level of infestation 1 (25.0%) 3 (75.0%) 4Infested with cockroach 9 (60.0%) 6 (40.0%) 15Total 10 (52.6%) 9 (47.4%) 19

of trap damage can be associated with existing factors in thesurveyed location.

The other effective factors on cockroach infestations areexclusion factors related to urban buildings. In this survey35% of units (from 319 units) had opening in the wall or roofwithout screen.The frequency of this factor for infested unitsin three surveyed dormitories was 43% versus 33% for cleanlevel units. However, there was no significant (𝑃 = 0.05)correlation between infestation and opening in the wall orroof.

Crack and crevices had been detected for 39% of units(from 306 units). Frequency of crack and crevices for infestedunits of three dormitories was 15% versus 27.5% for cleanlevel units. However, there was no significant (𝑃 = 0.05)correlation between infestation levels and crack and crevices.

Survey on 19 kitchens of dormitories showed electricair fans (air conditioner fans) had been screened for 60%infested kitchens versus 25% clean level kitchens. There wasa significant correlation (𝑃 < 0.05, Spearman) betweenscreened fans and infestation (𝑟 = −0.396, 𝑃 = 0.047)(Table 5).

Kitchen drains were not screened in 53% of infestedkitchens versus 25% clean level kitchens in these dormitories.However, there was no significant correlation (𝑃 = 0.05)between infestation and unscreened drains.

Based on the residence opinions (survey on 283 residen-tial units), the sources of cockroach infestation are the toilet(65.7%), kitchen (40.3%), rubbish containers (22.3%), andneighbors’ residence (21.6%) (Table 6). German cockroachesprefer dry habitats with a nearby water source such askitchen and bathroom [38]. Stephan [39] reported 65%of the emigrants German cockroach came from adjoiningkitchen areas. However, the American cockroach (with 0.6%frequency in the surveyed dormitories) prefers wet andmoistlocations such as sewers and toilet. Toilet and kitchen withhigh frequency of choice by respondents could be the mainentrance-source of these species. However, the local name of

International Journal of Zoology 5

Table 6: The entrance-source of cockroaches according to standpoint of occupants for 283 surveyed units of dormitories.

The entrance-source ofcockroaches

Toilet Housekitchen Neighbours Rubbish

containers

NandT

NandR

TandR

TandK

N, T,andR

N, T,andK

T, K,andR

NandK

N, T,K,

and R

Others(yard ordrainage)

Didnotknow

Total

Frequency 97 39 16 11 6 7 8 44 10 3 9 1 18 7 8 283∗

Percentage 34.3 13.8 5.7 3.9 2.12 2.8 2.8 15.6 3.5 1.1 3.2 0.4 6.4 1.2 2.8 100∗348 residents were questioned, although 81% of them had answer. T: toilet, K: kitchen, R: rubbish container, and N: neighbours.

cockroach in the research country is bath beetle which camefirst from the American cockroach and their harborage. Thisname may have misled some people to choose toilet as thehighest incidence rate for the entrance-source.Therefore, thestudy shows that the viewpoints of the residents about theentrance-source and predominant species concur with theresult from the cockroach trap counts. Seventy percent ofoccupants in the surveyed dormitories and housing complex(from 167 units; Table 4) encountered cockroaches with sizesless than 1.5 cm (the German cockroach size) close to therate of the German cockroach-infested units of the samebuildings detected via trapping (82% from 148 infested units;Table 1). However, incidence of infested units encounteredby residents was 28% higher than that estimated from thecockroach traps counts exercise.

In conclusion, more attention needs to be given to view-points of residents and factors affecting population (moni-toring methods, damages, and exclusion) when conductinga survey on cockroach in urban communities.

Acknowledgments

The authors are grateful to Professor Dr. Dzolkhifli B. Omar,Prof. Dr. Yusof B. Ibrahim, Dr. Mohd Khadri Shahar, andDr. Faizah Abood for technical help and their guidance forthe duration of this project. They thank the Vice-Chancellorof Yasuj University of Medical Sciences, Yasuj University,Azad University, and Tarbiat Moallem University for theirinvaluable assistance for access to the study sampling units.

References

[1] D. G. Cochran, “Cockroaches,” Technical Report,World HealthOrganization, Geneva, Switzerland, 1982.

[2] R. J. Brenner, “Economics and medical importance of Germancockroaches,” in Understanding and Controlling the GermanCockroach, M. K. Rust, J. M. Owens, and D. A. Reierson, Eds.,pp. 77–92, Oxford University Press, New York, NY, USA, 1995.

[3] M. A. Baumholtz, L. C. Parish, J. A. Witkowski, and W. B. Nut-ting, “The medical importance of cockroaches,” InternationalJournal of Dermatology, vol. 36, no. 2, pp. 90–96, 1997.

[4] H. Fathpour, G. Emtiazi, and E. Ghasemi, “Cockroaches as res-ervoirs and vectors of drug resistant Salmonella spp.,” IranianBiomedical Journal, vol. 7, no. 1, pp. 35–38, 2003.

[5] P. Saichua, K. Pinmai, S. Somrithipol, and S. Tor-Udom, “Iso-lation of medically important fungi from cockroaches trappedat Thammasat Chalermprakiat Hospital,” Thammasat MedicalJournal, vol. 8, no. 3, pp. 345–351, 2008.

[6] Y. M. Tatfeng, M. U. Usuanlele, A. Orukpe et al., “Mechanicaltransmission of pathogenic organisms: the role of cockroaches,”Journal of Vector BorneDiseases, vol. 42, no. 4, pp. 129–134, 2005.

[7] H.H. Pai,W. C. Chen, andC. F. Peng, “Cockroaches as potentialvectors of nosocomial infections,” InfectionControl andHospitalEpidemiology, vol. 25, no. 11, pp. 979–984, 2004.

[8] S. J. N. Devi and C. J. Murray, “Cockroaches (Blatta and Peripla-neta species) as reservoirs of drug-resistant salmonellas,” Epide-miology and Infection, vol. 107, no. 2, pp. 357–361, 1991.

[9] H. H. Pai,W. C. Chen, and C. F. Peng, “Isolation of bacteria withantibiotic resistance from household cockroaches (Periplanetaamericana and Blattella germanica),” Acta Tropica, vol. 93, no.3, pp. 259–265, 2005.

[10] E. P. Benson, Ecology and control of the smokybrown cockroach,periplaneta fuliginosa (Serville), in South Carolina [M.S. thesis],Clemson University, Clemson, SC, USA, 1988.

[11] J. Lane, R. Siebers, G. Pene, P. Howden-Chapman, and J. Crane,“Tokelau: a unique low allergen environment at sea level,”Clini-cal and Experimental Allergy, vol. 35, no. 4, pp. 479–482, 2005.

[12] C. Y. Lee, N. L. Chong, and H. H. Yap, “A study on domiciliarycockroach infestation in Penang, Malaysia,” Journal of Bio-sciences, vol. 4, pp. 95–98, 1993.

[13] C. Y. Lee and L. C. Lee, “Diversity of cockroach species andeffect of sanitation on level of cockroach infestation in residen-tial premises,” Tropical Biomedicine, vol. 17, pp. 39–43, 2000.

[14] P. Oothuman, J. Jeffery, M. Z. Daud, L. Rampal, and C. Shekhar,“Distribution of different species of cockroaches in the districtof Kelang, Selangor,” Journal of the Malaysian Society of Health,vol. 4, pp. 52–56, 1984.

[15] H. H. Yap, N. L. Chong, P. Y. Loh, R. Baba, and A. M. Yahaya,“Survey of domiciliary cockroaches in Penang, Malaysia,” Jour-nal of Biosciences, vol. 2, pp. 71–75, 1991.

[16] H. H. Yap, C. H. Ong, N. L. Chong et al., “Cockroach infestationin different household settlements in rural, suburban and urbanareas on Penang Island, Malaysia,” Journal of Biosciences, vol. 8,pp. 182–186, 1997.

[17] C. Y. Lee and W. H. Robinson, Handbook of Malaysian House-hold and Structural Pests, Pest Control Association of Malaysia,Kuala Lumpur, Malaysia, 2001.

[18] C. Y. Lee,H.H.Yap,N. L. Chong, andZ. Jaal,UrbanPest Control,Vector Control Research Unit, University Science Malaysia,Kuala Lumpur, Malaysia, 1999.

[19] J. Goddard, Physician’s Guide to arthropods of Medical Impor-tance, CRC Press, Boca Raton, Fla, USA, 4th edition, 2003.

[20] W. Ebeling, Urban Entomology, University of California Press,Berkeley, Calif, USA, 1978.


[21] D. G. Cochran, “Monitoring for insecticide resistance in field-collected strains of theGerman cockroach (Dictyoptera: Blattel-lidae),” Journal of Economic Entomology, vol. 82, no. 2, pp. 336–341, 1989.

[22] H. Ladonni, “Susceptibility of Blattella germanica to differentinsecticides in different hospitals in Tehran-Iran,” Journal of theEntomological Research Society, vol. 23, pp. 12–13, 1993.

[23] H. Ladonni, “Susceptibility of different field strains of Blattellagermanica to four pyrethroids (Orthoptera: Blattellidae),” Ira-nian Journal of Public Health, vol. 26, pp. 35–40, 1997.

[24] M. K. Rust and D. A. Reierson, “Comparison of the laboratoryand field efficacy of insecticide used forGerman cockroach con-trol,” Journal of Economic Entomology, vol. 71, no. 4, pp. 704–708, 1978.

[25] A. A. Hanafi-Bojd and S. Sadaghiani, Cockroaches of Iran, Teh-ran University of Medical Sciences and Health Services Press,Tehran, Iran, 2001.

[26] A. Nemati, Kohkiluyeh va Boyer Ahmad Tourism Attractions,Iran Tourism Online, Tehran, Iran, 2008.

[27] Anon, Annual Statistics of Province of Kohkiluyeh va Boyerah-mad, Provincial Office of Meteorology, Yasuj, Iran, 2004.

[28] D. A. Reierson, Ed., Understanding and Controlling the GermanCockroach, Oxford University Press, New York, NY, USA, 1995.

[29] A. G. Appel and B. L. Reid, “Sampling German cockroach fieldpopulations: theory, reliability, and analysis,” in Proceedings ofthe National Conference on Urban Entomology, College Park,Md, USA, 1992.

[30] W. J. Bell, L. M. Roth, and C. A. Nalepa, “Social behavior,” inCockroaches: Ecology, Behavior, and Natural History, H. E. Hin-ton, Ed., p. 230, JHU Press, Baltimore, Md, USA, 2007.

[31] G. K. Joseph, The Cockroach, University of Massachusetts,Massachusetts, Mass, USA, 2007.

[32] J. H. Paige, Seasnality and population dynamics of Germancockroaches, Blattella germanica (L) (Dictyoptera: Blrttellidae)in single family dwellings in Texas [Ph.D. thesis], Texas A&MUniversity, Texas, Tex, USA, 1989.

[33] B. L. Brenner, S. Markowitz, M. Rivera et al., “Integrated pestmanagement in an urban community: a successful partnershipfor prevention,” Environmental Health Perspectives, vol. 111, no.13, pp. 1647–1653, 2003.

[34] V. K. Agrawal and R. Tilak, “Field performance of imidaclopridgel bait against German cockroaches (Dictyoptera: Blatellidae),”Indian Journal of Medical Research, vol. 124, no. 1, pp. 89–94,2006.

[35] C. Y. Lee, N. L. Chong, and H. H. Yap, “Laboratory evaluationof three traps against Periplaneta americana (L.) and Blattellagermanica (L.),” Tropical Biomedicine, vol. 11, pp. 11–15, 1994.

[36] L. M. Smith and A. G. Appel, “Comparison of several traps forcatching German cockroaches (Dictyoptera: Blattellidae) underlaboratory conditions,” Journal of Economic Entomology, vol.101, no. 1, pp. 151–158, 2008.

[37] C. Wang and G. W. Bennett, “Comparative study of integratedpest management and baiting for German cockroach manage-ment in public housing,” Journal of Economic Entomology, vol.99, no. 3, pp. 879–885, 2006.

[38] P. G. Koehler, R. S. Patterson, and W. R. Martin, “Susceptibilityof cockroaches (Dictyoptera: Blattellidae, Blattidae) to infectionby Steinernema carpocapsae,” Journal of Economic Entomology,vol. 85, no. 4, pp. 1184–1187, 1992.

[39] R. E. Stephan, Factors influencing the movement German cock-roaches [Ph.D. thesis], Purdue University, Purdue, Ind, USA,1984.

Submit your manuscripts athttp://www.hindawi.com

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Anatomy Research International

PeptidesInternational Journal of


Hindawi Publishing Corporation http://www.hindawi.com

International Journal of

Volume 2014

Zoology


Molecular Biology International

GenomicsInternational Journal of


The Scientific World JournalHindawi Publishing Corporation http://www.hindawi.com Volume 2014


BioinformaticsAdvances in

Marine BiologyJournal of



Signal TransductionJournal of


BioMed Research International

Evolutionary BiologyInternational Journal of



Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttp://www.hindawi.com Volume 2014


Genetics Research International


Advances in

Virolog y

Hindawi Publishing Corporationhttp://www.hindawi.com

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational



Enzyme Research


International Journal of

Microbiology

research article cockroach infestation and factors...

Documents