Journal of the American Mosquito Control Association, 19(4):2g6_296,2OO3 Copyright @ 2OO3 by the American Mosquito Control Association, Inc.

GEOGRAPHICAL DISTRIBUTION OF ANOPHELES DARLINGI IN THE AMAZON BASIN REGION OF PERU

GEORGE B. SCHOELER,' CARMEN FLORES-MENDOZA,2 ROBERTO FERNANDEZ,' JORGE REYES DAVILA3 eNo MICHAELZYZAK4

ABSTRACT MaIaTia has reemerged as a significant public health disease threat in peru, especially within the Amazon Basin region. This resurgence plasmodiu- of human caies caused by infection with TaLiporum and Plasmodium vivax is thought to be associated with the spread of Anopheles dartingi, the priniipal'South American malaria vector, into new areas of the Amazon Basin. However, comprehensive studies of the distri- bution for this species have not been conducted in Peru for several yea.., no.^a." historical accounts accurare enough to determine if An. darlingi was actually present and not iollected or misidentified. Therefore, the objective of this study is to define the distribution of An. dartingl as well as obtain data on distribution and abundance of othet Anopheles species in this region. Mosquitoes were collected during 2001 in the Departments of Loreto and Ucayali, the two largest Amazonian Departments of Peru. A total of 60,5-85 specimens representing 12 species of the subgenera Nyssorhynchus and Anopheles were collected at 82 (88.2Vo)bf 93 colleciing sites. The majority of mosquitoes obtained were identified as An. benarrocftl, comprising 7O:7Eo of mosquitols col- lected, followed by An. darlingi (24.OVo),Anopheles mattogrosensis (2.4Eo), uid Anoph"l"t triannulitus (l.57o). Anopheles darlingi was collected from 48.89o of sites, indicating that this specieJ is established throughout T c€ntral 'oreto, including further west in the Amazon Basin than previously reported. These data rrrgg".i that this species is now found in areas of the Amazon Basin region where it has noi been previously ."po-ri"d.

KEY WORDS Anopheles darlingi, Amazon, peru, malaria

INTRODUCTION only 641 cases of malaria were reported to the Lor- eto Health Department in 1964; Human malaria remains the single most important 123 of these were caused by P. (Roper arthropod-borne disease of humans worldwide (Ket- falciparum et al. 2000). By 1997, the number of P. tle 1995, WHO 1998). While effective chemopro- falciparum and P. vivax cases reached 121,268, accounting phylactic measures and drug treatment regimes are for over 62Vo of reported malaria cases in Peru (Arambuni available to prevent and treat malaria infections, et al. 1999). Confirmed P. widespread resistance to chemoprophylactic agents falciparum cases exceeded 54,000, with 85 reported deaths in year (Roper and resistance of vectors to insecticides are major that et al. 2000). From 1992 to L997, malaria factors contributing to the resurgence of malaria in cases in- creased 5O-fold in Loreto, compared with many regions of the world (Lane and Crosskey an in- 1993, Kettle 1995). crease of only 4-fold for the rest of Peru (Aramburu et al. 1999). By 1999, Peru reported the Since the early 1990s, the incidence of malaria, second highest number of malaria cases in South America caused by Plasmodium vivax (Grassi & Feletti) and Plasmodium (Welch), next to BrazTl, most from Loreto (Arambuni et al. falciparum has increased 19e9). greatly in Peru (OGE 1997, Roberts et al. 1997). This resurgence in malaria incidence, The Peruvian Ministry of Health reported a 7-fold both P. fal- ciparum and P. vivax, is thought increase in the incidence of malaria from 13 per to be related to the spread of Anopheles 10,000 persons in 1990 to a high of 88 per 10,000 darlingi Root, the predom- inant malaria vector in the Amazon (Loun- persons in 1996 (Roper et al. 2000). Malaria caused Region ibos and Conn 2000). Prior to 1991, An. darlingi by P. falciparum infection previously occurred only was not reported from (Faran sporadically along the northeastern borders ofPeru, the city oflquitos and Linthicum 1981, Need et al. 1993a); however, but now accounts for approximately one third of all by 1996, malaria cases in the country (OGE 1997, Roberts this species was found in several communi- et al. 1997, Roper et al. 2000). ties surrounding Iquitos and even within the city itself (Ferndndez The Amazon Basin Region of Peru, with an es- et al. 1996). Anopheles darlingi timated population of 474,000 has been the major has now been reported from other areas of the Pe- focus of the malaria epidemic in Peru. For example, ruvian Amazon Basin, and evidence suggests that this species is spreading into previously uninfested areas of the Amazon Basin, particularly rNavy within the Disease Vector Ecology and Control Center, Department of Loreto (Ferndndez et al. 1996, Ar- 2850 Thresher Avenue, Silverdale, WA 98315. ambuni et al. 1999). Comprehensive studies of the 2 Department of Entomology, U.S. Naval Medical Re- geographical distribution search Center Detachment, APO AA 34031. of this species in the Pe- 3 Ministry of Health, Iquitos, Peru. ruvian Amazon Basin have not been conducted for a Armed Forces Pest Management Board, WRAMC, many years (Calder6n et al. 1974, Calder6n et al. Forest Glen, Building 172, 69m Georgia Avenue, NW, r99s). Washington, DC 20307-5001. Anopheles darlingi is considered to be the most

286 DecBrrmen2003 Anopaans o,qnunu D$rnrsurloN IN PERU 287

-h\

i Anopheles darlingi a An darlingi not collected.

0 m 2$kr

Fig. 1. Localities where Anopheles darlingi were collected on human bait within the Departments of Loreto and Ucayali, Peru, 2001.

efficient malaria vector in the New World (Foote Basin could lead to an intensification of malaria and Cook 1959, Manguin et al. 1999), including transmission in endemic areas and the spread of areas of the Peruvian Amazon (Faran and Linthi- malaria into new areas of Peru. The objective of cum 1981, Fernflndez et al. 1996, Arambuni et al. this study was to define the geographic distribu- 1999, Manguin et al. 1999). Anopheles darlingi is tion of An. darlingi in the Amazon Basin Region highly anthropophilic and susceptible to both P. of Peru for use in follow-up studies to determine falciparum and P. vivax infections (Manguin et al. the overall pattern of spread of this species in Peru 1999). Because of its importance as a vector of as well as to obtain information on the abundance malaria in the Amazonian region, spread of An. and distribution of other Anopheles species from darlingi into new areas of the Peruvian Amazon this region. 288 JounNnl oF rHe AN4BRrcaNMosqutro CoNrnor- AssocranoN Vor. 19.No.4

Table 1. Total number of anophelines collected on human bait, percentage of the total collected, and the number of localitieswhere each species was collected in thePeruvian Amazon Basin,2001.

Speciesof anophelines Total Percentage of No. of localities (Subgenus) collected total collected collected from (Vo) Nyssorhynchus darlingi r4,521 24.O 40 (48.8) benarrochi 4' R<5 70.7 32 (39.O) rangeli 752 0.3 8 (9.7) triannulatus 942 1.5 r8 (22) oswaldoi s.l.l 249 o.4 23 (28.O) nuneztovari J <0.1 1 (1.2) Anopheles mattoSrossens6 1,478 2.4 t7 (45 l\ Sp. near forattinii 140 0.3 r8(21.9) intermedius 69 0.1 r0 (r2.2) Sp. neat fluminensis 21 <0.1 5 (6.1) peryassut 52 <0.1 4 (4.e) nimbus 103 o.2 '9u, Total 60,585 loo.0 I An. oswaldoi s./. includes An. konderi Galvao & Damasceno and An. oswadol s.s. (Flores-Mendoza 1999).

MATERIALS AND METHODS area and trained them in procedures for collecting mosquitoes that landed on humans. Therefore, dif- Mosquitoes were collected throughout 2001 in ferent volunteers participated in mosquito the Departments of Loreto and Ucayali, ttre 2larg- collec- tions at each of the study sites. Individuals trained est Amazonian Departments of northeastern Peru were health technicians, health promoters, and res- (Fig. l). Collections were typically conducted for I idents from each study site where night in each locality unless An. darlingi was not collections were performed. Individual collected, in which case collections often continued collecting team members were randomly pairs for l-2 additional nights to confirm that this species assigned as to each collecting was not collected at that site. area at each study site. Mosquitoes were collected at hourly intervals The Department of Loreto comprises almost one from 1800 to 0600 h in each site during the fourth of the landmass of Peru and has an ecosys- study. Anophelines were collected fol- tem characteristic of the Amazon lowlands (Ar- lowing standard procedures using humans to attract (WHO ambuni et al. 1999). The city of Iquitos is the only mosquitoes 1975). Briefly, this involved a large urban center in Loreto, with a population of human volunteer using a flashlight and mouth as- approximately 345,000. The rural population of pirator to aspirate all mosquitoes landing on both Loreto, estimated at approximately 474,000 inhab- exposed legs, from the knee to the ankle. Human- itants, is clustered in towns and villages throughout landing collections were made for 50 min, with a the Amazon tributary system. The climate in this 10-min resVbreak period, every hour during each area is typical of the Amazon Basin, with a rainy l2-h collecting period. Collected mosquitoes were season from November to May and a dry season placed in appropriately labeled paper cartons and from June through October. The Amazon River lev- transported to laboratory facilities in Iquitos for el at Iquitos varies up to 9 m annually; the highest identification and further processing. All Anopheles levels usually occur from April to May. The mean mosquitoes collected were identified to species us- annual temperature is approximately 25"C, with in ing morphological characters and taxonomic keys excess of 25O cm of precipitation annually (Pefl- available for the anopheline species of this region aherrera-del-Aguila 1989, Need et al. 1993a). The (Gabaldon et al. 1941, Galvdo and Damasceno 1942,Faran 1980, Faran peak transmission rates for both P. falciparum and and Linthicum 1981). P. vivax occur during the rainy season, from No- The study protocol was approved by institutional vember through June (Arambuni et al. 1999). review boards at the Naval Medical Research Cen- Mosquitoes were collected in areas where the Pe- ter (protocol DoD 31557) in compliance with all ruvian Ministry of Health had reported malaria cas- Federal regulations governing the protection of hu- es as well as areas where An. darlingi had, or had man subjects. The use of humans was essential for not, been reported. Additional collection sites were collecting anthrophilic Anopheles, which are not of- chosen throughout the region to obtain information ten collected using other methods. For example, in from as many distinct geographical areas as possi- an arbovirus surveillance study conducted in a for- ble. ested area near Iquitos In 1999, in 84 trap-nights Upon arrival at each study site, the technician in where COr-baited light traps and human bait were charge of collections solicited volunteers from the used for mosquito collections, 97Vo of An. darlingi DrcBNasBn2003 Auopguts ntn Ncl DIsTRIBUTIoNN Pepu

N r

c.)

ol o

o0 o

Ito €co .F o$N-c-.1 N *

o o

0

(A o

*O\€ cli o Nal al

O\€ v ; o o N

O o N 00 * o d

x >,9 ot\ NNc.l 60lc.l 2EE 6i o z) ^- e z) eej & 'F,^2 & '{E 6 oa !i g O:Y .= d.i g, >-& sxBi *" ! ttt=rE€i s: o ov xi !Ho *; o .: .F .3 =F 6 gF E'F?s HREHa.ERE-=Ei E; igg Ei>N; 95 -F e +* : ,i EEEEE?gE

i5..: g A h00 o 3E3IissHiF3 i5 'Igi sgI !i5i:!ff EEt;3i!i 290 JounNer-or rnp AvsrucaN Mosquno CoNrnol AssocranoN VoL. 19,No.4

N ti

s c.)

: -.r

N\O*

$ 00 00 N 00r) NO ol c.l 6

ol F..r)

o I o Ca) r)\o 00r)* o o

O c-.1 !)

F F.,

r) cno q\ :f, r- F- viql'- ci s6

f\d

o\!+o \NN *c! NN

!: oP x >,9 ciN \Oi zzE ole*5

a ^aa i d*Q it?-- 4" 9Ev'c*'i 'i "-d o ov i ?; i t? ?+ ix kHo $+g.*ig., x;i o E:,rEg :E a Ebc ?iiisn's i*E FF? iSgieEE? "s€i$ur il$:€

E.:.9 A ;oE 3?i*EiE iiE !Ei E} iE if{!E Eii ?i $iEifFi ;s;il s b s $;E I E; $$;; 4s;;I €$; $g sl$frs:; DpceNaepn2003 Axopnrtts oaaalrcr DtsrnrnuttoN rN PBnu 29r

N

olo olo c'.1

.;a N

o (r) =rO o s; + 0

U c.l

C'.lO\ -6O\ O\oo\ ol@€O- nr) \o\o- O\ +€ $c{ dl d; N

@Oo 6l \O c.r O r- 6n6OOa.l Or-r@Nn c..t: *\OCiCn -6o+c-.1- o n--N ca o a'l - c.l ci d -v c] -i

*Fi*iN -OliFi* a.lii:ic'l

-: A /_)

,i-e 'i'--c4

Hiio *: o r.i.E EP @ EFEtgE,rib€ sEniEs€EAE r"{ifi ,rE€n ?;E a.:9 x boo o EIEliliiEHgg gl;FiEFi I$EiiE; BIFHI ;;F 292 Jouwel oF THEAMERTcAN Moseurro CoNrRol Assocrnrror.r Vor, 19,No.4

co

\o c-.1 \ s F s

c.l 6

E

Ft ;

@

z Nhd *@ t- \ o

I o r (h *\OnF E $ o N

x Q F-Olr+- ol N

N 0

F ciO\*F- $N NH :

oo -c{ O\r) F-n O\€

o co 00 N ot ot v a-l

=f aax x xv T4 C.l r.F zo3 j

"d € a2 rg e; ra!i 9;voF h .= d.n 2r >^H E $* '!g o 0v >e^EE,; \< kHo *;i u .r.F.E N .;' Ep a i igt,!*eEF 96c i;f ie :EF Ei;,rsie5 s .:.i P o'5 Et i n;€49 5sr :s a:9 EE€rai : i 3gi1:5;i !i; *_ti A boo gi I ti EfriJE sti ?*sti I :silEEii sF sx;* g;;I -6 f,l$'uriS ssud E - t1dr66ds {Jil." *ii DecEN4spn2003 ANopHELEs DARUNGTDrsrrrsufloN rN Penu collected were from human bait (M. J. Turell. 1999. in the Amazon Basin region. This increase in ma- unpublished data). In another lO-wk study con- laria occurrence is thought to be due to the spread ducted in Padre Cocha, a village located on the Riv- of An. darlingi into the Amazon Basin region, com- er Nanay near Iquitos, 2,162 An. darlingi were col- bined with changing river-use patterns, jungle ex- lected from human-landing collections, while only ploitation, and the reduction in residual insecticide 88 were collected in light traps baited with CO, and treatments that were conducted prior to the l99Os octanol, and 77 from light traps baited only with (Roberts et al. t997, Arambuni et al. 1999, Roper CO, (A.S.T. Chan, unpublished data). et at. 2000). Because the spread of An. darlingi into new areas of the Amazon Basin may be a major factor in the resurgence of human malaria in Lor- RESULTS eto, this study was conducted to determine the cur- Within the Amazonian Departments of Loreto rent distribution of this species within the Amazon and Ucayali, adult anopheline mosquitoes were col- region of Peru. Current distribution data are needed lected at 82 of 93 (88.2Vo) collection sites. The re- to establish the present range of this species and is maining l l sites yielded no anophelines. A total of critical to determine if An. darlingi is indeed 60,585 Anopheles mosquitoes were collected from spreading into previously uninfested regions in the human-landing collections, representing 12 species Peruvian Amazon. from two subgenera (Nyssorhynchas and Anophe- During 2001, collections conducted at 93 local- /es) within the genus Anopheles (Table 1). The ma- ities within the Departments of Loreto and Ucayali joity (7O.1Vo) of Anopheles species collected from yielded anophelines from 82 (88.2Vo) of the collec- all sites were An. benarrochi Gabaldon, Cova tion sites. anopheles darlingi was not collected at Garcia, &L6pez, followed by An. darlinei (24.A7a), any of the sites within the Department of Ucayali. An. mattogrossensis Lutz & Newa (2.4Va), and An. However, An. darlingi has previously been reported triannulatus (Neiva & Pinto) (l.5%o). The remain- from Madre de Dios, another Amazonian Depart- ing anopheline species collected, An. rangeli Ga' ment of Peru (Calder6n et al. 1995). These data, baldon, Cova-Garcia & L6pez, An. oswaldoi s.l. combined with previous reports, suggest that at pre- (Peryassu), An. sp. near forattinii Wilkerson & Sal- sent this species is found within the Amazon Basin lum, An. ifiermedius (Peryassu), An. sp. neat flu' region of Peru only in the Departments of Loreto minensis, An. peryassui Dyat & Knab, An. nunez- and Madre de Dios. tovari Gabaldon, and An. nimbus (Theobald) Anopheles darlingi previously was reported only represented less than 2Vo of the total mosquitoes from the eastern areas of the Peruvian Amazon Ba- collected (Table 1). sin near the borders of Brazil and Colombia, ex- Among all Anopheles species collected, An. dar' tending westward to the Iquitos area (Calder6n et lingi was found at the greatest number of sites al. 1974, 1995). Additionally, during mosquito col- (48.8Vo) (Table 1). An. darlingi was not collected lections, including human-landing collections, con- in the Department of Ucayali. Although only 1,478 ducted between 1988 and l99l at 3 forested sites An. ma.ttogrossensis were collected, it was captured near Iquitos, over 35,000 mosquitoes of 13 genera at more sites (37) than any of the other anopheline and25 species were obtained, and these collections species, except An. darlingi. Further, even though yielded no An. darlingi (Need et al. 1993). Ferndn- An. benarrocfti was collected frequently, it was col- dez et al. (1996) reported the presence of An. dar- lected from fewer sites (32) than was An. darlingi lingi in the vicinity of Iquitos for the first time dur- or An. mattogrossensis. Figure 1 shows the sites ing collections conducted in 1995; this species is within the Department of Loreto from which An. now well established in the Iquitos area (Arambuni darlingi was coliected during the present study. Ta- et al. 1999, Roper et al. 2000). In addition, An. ble 2 provides coordinates of districts within the darlingi had not been collected previously from the Department of Loreto in which collection localities western regions of the Amazon Basin extending to were located, and number of anophelines, of each the foothills of the Andes. For example, in Andoas, species, collected at each study site, All collecting a region located about 350 km west-northwest of sites were located along the rivers listed in Table 2, Iquitos near the Ecuadorian border, six 2-wk mos- typically within 10 km of the grid coordinates pro- quito collections conducted in 1990-1991 yielded vided. These data demonstrate that An. darlingi is over 4,000 anopheline mosquitoes; no An. darlingi established throughout central Loreto, including were collected (Need et al. 1993b)' However, dur- further west in the Amazon Basin than previously ing the present study, An. darlingi was found much reported, suggesting that this species has spread farther west in the Department of Loreto than had into previously uninfested areas of the Peruvian been previously reported. Specifically, we collected Amazon Basin. An. darlingi along the Chambira River, at a site located approximately 265 km west of Iquitos, and approximately 130 km southeast of Andoas (Fig. DISCUSSION 1). Our collection data show that An. darlingi is In Peru, malaria has become a significant public now established throughout the central region of health threat during the last decade, especially with- Loreto, including far to the west of Iquitos, where I

JounNx- op rHp AwpnrceN Mosgurro CoNrnol AssocrlrroN Vor. 19,No.4

it was first reported in 1995 (Ferniindez et al. 1996). During the present study, 12 anopheline species Therefore, these data suggest that An. darlingi is representing 2 subgenera (Nyssorhynchus and indeed spreading into previously uninfested areas Anopheles) were collected from sites within the De- of the Amazon Basin of Peru. Alternativelv. this partments of Loreto and Ucayali (Table 1). The species may always have been present in these ar- most abundant anopheline species collected was eas but not previously collected due to very low An. benarrocfti, representing 7O.7Vo of mosquitoes population densities. For example, An. darlingi may obtained from these areas. Of ttre 12 species col- have always been present in these areas, but kept lected, the following are considered to be primary below detectable levels during the intensive malaria or secondary malaria vectors in forested areas of control programs conducted during the 1960s eastern Peru, based on salivary gland infections or through the early 1980s, when such programs were circumsporozoite enzyme-linked immunosorbent abandoned. Therefore, a combination of increasing assay (Wirtz et al. 1992) data: An. darlingi; An. abundance after extensive vector-control programs nunefiovari; An. rangeli; An. oswaldoi,.An. sp. near were discontinued, followed by population expan- fluminensis; and, An. mattogrossensls (Hayes et al. sion into new areas, may help explain the appear- 1987, Need et al. 1993b, Calder6n et al. 1995, Fer- peruvian ance of An. darlingi in areas of the Am- ndndez et al. 1996). Some or all of these species azon Basin where it was not previously reported. may serve as malaria vectors in forested areas of Our collections conducted during 2001 show that eastern Peru where An. darlingi has not been col- An. darlingi is found in the Amazonian Department lected. For example, in the Department of Junin, a of Loreto along the borders of Colombia andBrazTl high-jungle area located on the eastem slopes ofthe from 70'W longitude to approximately 76.W lon- Andes southwest of Iquitos, hyperendemic malaria gitude, and south from approximately Oo2, to occurs sporadically, and P. vivax is apparently 6'40'5 latitude. These data indicate that An. darlin- maintained by anopheline species other than An. gi peruvian is found in a much larger area of the darlingi. These include An. oswaldoi, An. nunez- Amazon than previously reported and may help to tovari, An. triannulatus, An. sp. nr. fluminensis, An. explain the resurgence of human malaria cases in trinkae, and An. rangeli (Hayes et al. 1987) species this area in recent years. The data obtained from also collected during the present study. this study should be used as baseline data; surveil- The malaria vector situation in endemic areas of lance for An. darlingi should continue in this area the Peruvian Amazon is not at all clear, especially to determine if An. darlingl is spreading further into with regard to An. benarrochi, the most abundant Loreto and other areas within the Amazon Basin mosquito collected during this study. Specifically, region "An. of Peru, which could have important con- Arambuni et al. (1999) states benarrochi is sequences in the epidemiology of malaria in this the dominant malaria vector in western Loreto, area. while An. triannulatus is the dominant vector in The distribution of malaria in Loreto is uneven, eastern Loreto." However, no data are presented to with several zones of high transmission and larger confirm the vector status of these species (Aram- areas where malaria transmission and disease inci- burri et al. 1999). Indeed, An. benanochi, which dence occur at lower levels (OGE 1997, MINSA, may be the dominant species in malaria-endemic Loreto 1998, Arambuni et al. 1999, Roper et al. areas in the absence of An. darlingi, and which rep- 2000). Epidemiological evidence suggests that oth- resented over TOVoof the mosquitoes collected dur- er Anopheles species might be responsible for ing this study, was discounted as a vector in North- maintaining and transmitting human malaria in en- ern Brazil based on the dissection of 31 females in demic areas of Peru where An. darlingi has not 1948 (Deane et al. 1948). In another studv con- been reported. For example, in Pucallpa, the largest ducted by Klein et al. (1991), An. benarrr,ttlhi, .*- urban center in the Department of Ucayali, 2,852 perimentally infected with P. vivctx, developed oo- cases of malaria were reported in 1997, 557 cases cysts, but were never observed to have sporozoites were reported in 1998, and 363 malaria cases oc- in the salivary glands, suggestingthat this species curred in 1999, all in an area where An. darlingi may not be an efficient malaria vector. However, has not been found (MINSA, Ucayali 2OOl). In yu- An. benarroc&i has been implicated as the primary rimaguas, a city in the extreme western area of Lor- vector of malaria in areas of the Peruvian Amazon, eto,82 cases of malaria were reported in 2001, and where it occurs in high numbers, accounting for up in Andoas, 176 cases were reported in 1999, both to 98Vo of the anopheline fauna in the Amazonia areas where An. darlingi has not been reported lowlands, areas where both P. falciparum and p. (MINSA, Loreto 2001). Therefore, in malaria-en- vivax are endemic (Calder6n et al. 1974, Arambuni demic areas of the Peruvian Amazon, other Anoph- et al. 1999). Additionally, An. benanochi was re- e/es species apparently are responsible for trans- ported as a principal malaria vector in the Depart- mitting malaria in areas where An. darlingi does ments of Loreto and Ucayali by Calder6n et al. not occur. For that reason, the objectives of this (1995). Ferniindez et al. (1996) reported the pres- study also included investigating the abundance and ence of Plasmodium circumsporozoite proteins in 9 distribution of other Anopheles species in this re- pools containing 37 female An. benarrochi collect- gion. ed near Iquitos (Fern6ndez et al. 1996), demonstrar- DscsNrsrn2003 ANqPHELES DARLlr'Gl DISTRIBUTION IN PERU 295 ing natural Plasmodium infection in this species. ciones sobre su abunduncia e infectividad en el Peru. Further studies are required to determine the im- Rev Peruana de Epi.demiol 8(1):5-23. portance of An. benarrochi and other Anopheles Deane LM, Causey OR, Deane MP. 1948. Notas sdbre a distribuigSo e a biologia dos anofelinos das regi6es Nor- species as malaria vectors in the Amazon Basin re- destina e Amazdnica do Brazil. Rev do ServiEo Especial gion of Peru, especially due to the abundance and de Sdude Piblica l:827-965. wide distribution of this species in the Peruvian Faran ME. 1980. Mosquito studies (Diptera: Culicidae) Amazon. XXXIV. A revision of the Albimanus section of the The data obtained from this study clearly show subgenus Nyssorhynchus of Anopheles. Contributions that An. darlingi is more widely distributed within Am Entomol Institute (Ann Arbor) l5(7):l--215. the Amazon Basin region of Peru than previously Faran ME, Linthicum KJ. 1981. A handbook of the Am- reported. However, the question remains as to azonian species of Anopheles (Nyssorhynchus) (Dip- whether the distribution determined during the tera: Culicidae). Mosq Syst l3(l):1-81. course of this study represents an increase in the Fernindez R, Carbajal E Quintana J, Chauca H, Watts A. (N) darlingi (Diptera: Cu- range of this species, represents collections from DM. 1996. Presencia del licidae), en alrededores de la ciudad de Iquitos, Loreto- sites not previously sampled for this species, or per- Peru. Boletfn de la Soc Peruana de Enfermedades In- haps an increase in abundance of this species in fecciosas y Trop 5:lO-20. these areas following the decline of organized vec- Flores-Mendoza C. 1999. Variagoes fenotfpicas e genotip- tor-control programs. To determine if the distribu- icas en Anopheles oswaldoi s.l. (Diptera: Culicidae). tion of An. darlingi is indeed spreading into new Doctoral Dissertation. Rio de Janeiro: Institute Oswaldo areas of the Amazon Basin, continued accumula- Cruz. 156 p. tion of data on the distribution of this species, such Foote RH, Cook DR. 1959. Mosquitoes of medical im- as that obtained from this study, is required. These portance Washington, DC: U.S. Department of Agri- data should be used as baseline data on current An. culture. A, Lopez JA. 1941. Estudios darlingi distribution. Surveillance for An. darlingi Gabald6n Cova-Garcia \ sobre anofelinos serie ll. Anopheles (Nyssorhynchus) should continue in this area to determine if indeed benarrochi, una especie de la subserie triannulatus. Di- and An. darlingi is spreading further into Loreto vision de Malariologia de Venezuela 7:5-26. other areas within the Amazon Basin region of Galvdo ALA, Damasceno RG. 1942. Anopheles (Nysso- Peru. This information, coupled with further studies rhynchus) konderi nova especie de vale do Amazonas on the bionomics of other suspected and known e consideracoes sobre as especies do complexo tari- vector species will aid greatly in understanding the maculatus (Diptera: Culicidae). Folia Clin- Biol. Hig- epidemiology of human malaria within the Amazon Sao Paulo l4:115-135. Basin and may aid in helping to control the resur- Hayes J, Calder6n G, Falc6n R, Zambrano V. 1987. Newly gence of malaria among human populations in this incriminated anopheline vectors of human malaria par- Am Mosq area. asites in Junin department, Peru. J Control Assoc 3(3):418-422. Kettle DS. 7995. Medical and veterinary entomnlogyWal- ACKNOWLEDGMENTS lingford, UK: CAB International. Klein TA, Lima JR Tada MS, Miller R. 1991. Compara- The authors gratefully acknowledge L. Philip tive susceptibility of Anopheline mosquitoes in Ron- Lounibos, University of Florida, Douglas Watts, donia, Brazil to infection with Plasmndium vivax. Am Naval Medical Research Center, and Don Roberts, J Trop Med Hyg 45(4):463-47O. Uniformed Services University of the Health Sci- Lane RP, Crosskey RW 1993. Medical insects and arach- ences, for reviewing earlier versions of this article. zjds London: Chapman and Hall. We also would like to acknowledge Karin Escobeda Lounibos LR Conn JE. 2000. Malaria vector heterogeneity America. Am Entomol 46:238-249. for exceptional technical assistance.This work was in South Manguin S, Wilkerson RC, Conn JE, Rubio-Palis Y, Dan- supported by Work Information System (WUIS) off-Burg JA, Roberts DR. 1999. Population structure of 6287 A.87O.U.80003 funded through the Military the primary malaria vector in South America, Anoph- Infectious Diseases Research Program. The opin- eles darlingi, using isoenzyme, ITS2, RAPD, and mor- ions and assertions contained herein are the private phological markers. Am J Trop Med Hyg 6O:364-376. ones of the authors and are not to be construed as MINSA, Loreto [Ministerio de Salud, Direccion Regional official or reflecting the views of the Navy Depart- de Salud de Loretol. 1998. Boletin de Malaria. Iquitos, ment or the naval service at laree. Peru. MINSA, Loreto [Ministerio del Salud, Direccion Regional de Loretol. 2001. Programa de Control de Malaria y REFERENCES CITED OEM. Informe Operaccional de Malaria por Provincias. Aramburd GJ, Asayag CR, Witzig R. 1999. Malaria re- MINSA, Ucayali. [Ministerio de Salud, Direccion Region- emergencein the Peruvian Amazon region. Emerging al de Ucayalil 2001. Programa de Control de Malaria Infe t'r D is 5(2\:209-21 5. y OEM. Numero de casos de malaria de Ia region Uca- Calder6n G, Curaca A, Llancari J, Nap6n M, Sipan E yali. 1974.Distribucion geograficade los vectoresde malaria Need Jl Rogers EJ, Phillips IA, Falcon R, Fern6ndez R, en el Peru. Rev Peruana de Med Trop 2(2):88-91. Carbajal Il Quintana J. 1993a. Mosquitoes (Diptera: Calder6nG, FerndndezR, Valle J. 1995.Especies de la Culicidae) captured in the Iquitos area of Pent. J Med fauna anofelina" su distribucion y algunas considera- Entomol 30(3):634-638. 296 JounNeL op ruE AvenrcAN Moseuno Covrnol AssocralroN Vor-. 19, No. 4

Need JT, Wirtz RA, Franke ED, Fem6ndez R, Carbajal Il DDI global strategies, and a malaria control crisis in Falcon R, SanRoman E. 1993b. Plasmodium vivax South America. Emerging Infect Dis 3:295-302. VK247 and VK2l0 circumsporozoite proteins in Roper MH, Carrion RS, Torres C, Goicochea CGC, An- Anopheles mosquitoes from Andoas, Peru. "/ Med En- dersen EM, Guarda JS, Calampa C, Hightower AW, tomol 30(3):597-6O0. Magill AJ. 2000. The epidemiology of malaria in an OGE [Oficina General de Epidemiologia]. 1997. Situation epidemic area of the Peruvian Amazon. Am J Trop Med Epidemiologica Dafios Trazadores Lima: Ministerio de Hyg 62(2):247-256. Salud del Peru. Wirtz RA, Sattabongkot J, Hall T, Burkot TR, Rosenberg Pecor JE, Jones J, Turell MJ, Ferndndez R, Carbajal I R. 1992. Development and evaluation of an enzyme- O'Guinn M, Sardalis M, Watts D,Zyzak M, Calampa linked immunosorbent assay for Plasmodium vivax- C, Klein TA. 2000. Annotated checklist of the mosquito YK247 sporazoites. J Med Entomol 29(5):854-857. species encountered during arboviral studies in lquitos, WHO [World Health Organization]. 1975. Manual on Peru (Diptera: Culicidae). J Am Mosq Control Assoc practical entomology in malaria. Part II. Methods and l6(3):21O218. techniques. WHO Offset Publication 13. Geneva: World Pefraherrera-del-Aguila A, ed. 1989. Atlas del PeruLlma.. Health Organization. Instituto Geographico Nacional. WHO [World Health Organization]. 1998. Malaria Ge- Roberts DR, Laughlin LL, Hsheih P, Legters LJ. 1997. neva: World Health Organization.

Jo6d dhMn r&bhdffi, p.O.kzg, Ebbh, iJ otus

tu F Ctide., hE dEnrreot, Un@ dW, tu $* M, M, S gt*!s

J@ a&h. Jrm,tr b, lrc,,llOE 16sq tt*fu6. 6ss

lffirbMbr

2hbtub.dgcl@ tuhtbr&,el..hmdtudrruft Mdhd|Bild|6,'l\ll'lF rtr|4dbshh.'ffi. rihrl tFil,ddtub u.

. h tlh..*dtu, d |trfi i.t!&*@|d6rnsr, rdildbh@i0 ffi ffih m s, do, +k-q tu,.* -.drF*+h*nd4Md o!r& db& | dbFd hr bhdi thffi. d#6 &. h h