Journal of Health Sciences Management and Public Health RE-EMERGENCE OF MALARIA IN ARMENIA AND VECTOR CONTROL INTERVENTIONS
Lilit M. Avetisyan1
Abstract Malaria was highly endemic in Armenia from ancient times. Malaria control from 1945 was directed towards the elimination of the disease, and when this was achieved in 1963, towards the maintenance of this status. Since then, no autochthonous malaria cases occurred and therefore, the control operations were sharply reduced in 1991. After 1991, following the collapse of the Soviet Union, the situation became critical in terms of maintaining a malaria - free status (Armenia- country update- January, 2001). Several factors placed Armenia at risk for the re- emergence of malaria. Recent severe financial constraints contributed to reduction of vector control activities and for non-full-fledged epidemiological control new malaria cases may have not been diagnosed, treated and reported properly. In 1994 the first indigenous case occurred since malaria eradication. In the following years a straight rise of both imported and indigenous malaria cases was recorded, reaching a peak of 567 locally transmitted cases in 1997. All cases were due to P. vivax.
In 1998, a Roll Back Malaria program was developed to eliminate the recently established foci of malaria infection and to prevent the resurgence of malaria in Armenia.
The objectives of this program were: early detection and radical treatment of all malaria cases, availability of anti-malarial drugs and improved accessibility to the health services, indoor residual spraying in malaria foci with cyfluthrin 0.05 gr/m2, mosquito source reduction. Since 1998, the epidemic has been successfully contained and the number of indigenous cases has dramatically dropped down in 1999-2002, reaching the 56 cases in 2000, 32: in 2001 and 13: in 2002.
INTRODUCTION a rudimentary network of health Malaria was known to be highly institutions. After the establishment, endemic in Armenia from ancient in Yerevan, of the Tropical Medicine times. In the period 1920s-30s, Institute in 1923 and of a network of thousands of people were affected by anti-malaria stations in the 1920s- malaria and in 7 regions of the 1930s, the malaria situation greatly country (out of 11) and 3 cities improved; however, in 1934, still (Yerevan, Gumry, Diligan) were some 200,000 malaria cases were considered as malarious. Until 1923, registered in the country (4). From malaria control activities were the 1940s to the 1950s, with the rapid carried out on a very limited scale by development of health services, specialized malaria control institutions and social-economic 1 National Institute of Health, Department of Epidemiology, Yerevan, Armenia 138 Journal of Health Sciences Management and Public Health conditions, the malaria situation in were displaced from war strike the country improved further. By zones. In that year, 196 imported 1946, the number of malaria cases cases of malaria, all due to P. vivax. was reduced to 60,000, by 1950 to were recorded and the first 14,500 (6). During the malaria indigenous case of malaria was eradication period (1950s-1960s) detected in Masis Region (4). In 1994, comprehensive measures were the majority of imported cases undertaken (including indoor (91.8%) occurred in displaced spraying with residual insecticides, persons returning from conflict wide-scale hydro-technical areas. No patients received the environmental management). The appropriate radical treatment anopheline breeding places were because of the unavailability of dramatically reduced in number and primaquine in the country at that size as well as mosquito densities. time. Plasmodium falciparum and P. vivax were eradicated from the country by A further worsening of the malaria 1953 and by 1963 respectively. situation was observed in 1995, when 502 imported cases were recorded, After malaria eradication, due to the both among military and civilian progressive reduction of the vector people, but no indigenous cases control measures, anopheline were detected that year. In 1996, the populations started to reappear in epidemiological situation changed breeding places and the densities of dramatically: 149 indigenous cases potential vectors grew. In 1990, all were recorded out of a total of 347. vector control activities were sharply In 1997 a total of 841 cases was reduced due to the difficult reported, of which 567 (67.4%) were economical situation and, from 1991, indigenous (4). Most of these cases insecticides were not available (over 90%) occurred in the city of anymore in Armenia. Systematic Masis and in the close village of entomological investigations were Marmaraschen. All the remaining also reduced due to the lack of cases occurred in towns and rural transport and fuel facilities. villages of Ararat, Artashat and Echmiadzin districts, all located in In spite of sporadic malaria cases the Ararat valley. imported from abroad, until 1993 the malaria-free status was maintained In 1998, the Ministry of Health of in Armenia by a well-developed Armenia, with the technical network of public health oriented assistance of the World Health institutions (8). In 1994, the situation Organization (WHO) and financial changed in relation with the conflict contributions of the Governments of over Mountainous-Karabakh in Norway and Italy, resumed malaria which several thousands of people control activities. With WHO,
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UNICEF and the International Change in may 1993, is necessary to Federation of Red Cross and say, that Armenia, a mountainous Crescent Societies assistance, a Roll country with vulnerable ecosystems, Back Malaria (RBM) program was especially perceptible displays of implemented to eliminate the unfavorable consequences of global recently established foci of malaria climate change are to be expected. infection and to prevent further During the implementing the project spread of the disease in the country “Armenia- Country Study on Climate (8). The four elements of the Program Change”, were studied and the are as follows: changing of malaria situations in that - Disease Prevention: to plan and condition. The expansions of the implement selective and areas of the vectors and the sustainable preventive measures; aggravation of epidemic situation of - Disease Management: to provide malaria can be expected, because of early diagnosis and prompt the optimization of a temperature treatment; mode in the foothill, –upland zone - Epidemic Control: to detect early and time. The possibility of outbreaks and prevent further alleviation of malaria danger in the spread of malaria epidemic; semi-desert zone related to the - Program Management: to expected parching of swamps and strengthen institutional capacities reservoirs of this belt is observed (5). of the National Program and The aim of this paper is to provide surveillance mechanism (3). relevant historical and detailed recent epidemiological information The main strategic directions were: on malaria situation in Armenia and 1) early detection and radical to evaluate the impact of the first four treatment of all malaria cases; 2) years of the vector control availability of 3 antimalarial drags operations. (include primaquine for radical treatment, never available before MATERIALS AND METHODS 1998; 3) improved accessibility to the health services; 4) indoor residual Geographic background spraying in malaria foci; 5) mosquito Armenia is a country of 3.3 million source reduction; 6) health education persons and one of the 13 Newly and information; 7) strengthening of Independent States born after surveillance. Follow up of malaria dissolution of the Soviet Union. The cases for P. vivax relapses up to 12 capital city is Yerevan. Armenia months was also implemented. borders Azerbaijan, Turkey, and the Republic of Georgia (Table 1). This Considering, that the Republic of country is mainly mountainous with Armenia ratified United Nations a long, narrow valley, the Ararat Framework Convention on Climate valley follows the course of the river.
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Indigenous malaria cases in Armenia by regions and districts, 1998-2003 Year Indigenous Cases by region Cases by district malaria cases (total cases)
1998 542 (1,156) Ararat 507 (93.5%) Artashat 47 Vedi 97 Masis 358 Ararat city 4 Yerevan city 1 Armavir 35 (6.5%) Echmiadzin 35
1999 329 (616) Ararat 299 (91%) Artashat 34 Vedi 65 Masis 200 Armavir 25 (7.6%) Echmiadzin 25 Tavush 5 (1.4%) Idjevan 5
2000 56 (141) Ararat 18 (32%) Artashat 3 Vedi 15
Armavir 38 (68%) Armavir 27 Echmiadzin 6 Metsamor 4 Baghramyan 1
2001 32 (79) Ararat 15 (46,9%) Ararat city 3 Vedi 9 Masis 3
Armavir 17 (53,1%) Armavir 6 Echmiadzin 2 Metsamor 9
2002 13 (48) Ararat 10 (90,9%) Vedi 6 C.Ararat 3 Masis 1
Armavir 3 (9,1) Armavir 1 2003 8 (29) Ararat 8 (90,9%) Vedi 5 C.Ararat 1 Masis 2
Araks is where most of the and 39 districts (called Rayon). population is concentrated. The Between the years, 1998 and 2000, country is divided into 11 locally contracted malaria cases administrative regions (called Marz) occurred in 3 regions which included
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Ararat, Armavir, Tavush. Also VECTOR CONTROL included were 7 districts, as follows: ACTIVITIES Masis, Artashat, Vedi -Armavir, A round of indoor residual spraying Echmiadzin, Metsamor, and Idjevan. was carried out yearly in the malaria The first 6 of which are located in the foci of Armenia in 1998-2000. Houses, Ararat valley (Ararat and Armavir animal sheds and any other kind of regions) and the last one in the hilly premise of all villages and city areas region of Tavush (Table 1). where malaria cases had occurred, were sprayed with cyfluthrin (Solfac MALARIA TRANSMISSION 10 WP) at 0.05 gr/m2. Spraying CONDITIONS AND VECTORS operations were made at the In the most favorable conditions, that beginning of the transmission season are present in the Ararat valley, the (May-June). The residual activity was sporogonic cycle of P. vivax can take long enough to cover the place from the ending of May up to transmission period (4-5 months). To the second decade of October. In implement the larviciding program, foothill territories, sporogony can surveys were carried out to identify take place from July to September. Six the anopheline breeding places in the species of Anopheles were known to malaria foci. Only the sites of obvious be present in Armenia but only two epidemiological importance were played an important role in malaria targeted to improve operational cost- transmission: the main vector, effectiveness. Treatments were Anopheles sacharovi, a highly carried out in 1998 and 1999 with antropophilic and endophilc species, Bacillus thuringiensis israelensis and An. maculipennis s.s. considered (B.t.i.) (Bacticid, a Russian WP as a secondary vector (unpublished formulation) at rate of 2 Kg/ha (three reports, Armenian Ministry of times a year), and in 2000 with Health). As a consequence of the temephos (Abate 500 E) at rate of 200 vector control activities carried out g/ha (twice a year). Some more 800 in 1950-60’s, An. sacharovi ha of potential anopheline breeding progressively disappeared and had sites were treated yearly with not been reported since 1965. Recent Gambusia spp. fishes. The indoor entomological investigations carried residual spraying was carried out out within the RBM program also in 2001 in selected areas. revealed that. this species is again very common in all the malaria foci THE MALARIA SURVEILLANCE of the Ararat valley (7). Most of the SYSTEM anopheline breeding sites are A malaria surveillance system has freshwater pools in prairie blowout been re-established in Armenia with holes, often located near human the assistance of Center for Disease dwellings. Control (Atlanta, USA) and RBM. Reporting malaria, as well as other infectious diseases, is mandatory. 142 Journal of Health Sciences Management and Public Health
Local district laboratories diagnose (Table 1). (A total of 559,213 m2 were clinical cases of malaria treated with cyfluthrin in 1998, (536 microscopically and positive cases houses and 1,012 animal shelters in Table 2. Malariaare notified Integrate at Vector central Control level in Armenia,to the 1991-2002five districts). This figure increased Republican Center of Hygiene and to 1,259,637 m2 (2,133 houses and Substances used for treatment of the premises (water reserve) in 1991-2002 N Substance nameEpidemiological 1991 1992 1993 Surveillance1994 1995 1996 2,8371997 animal1998 shelters1999 2000 in five2001 districts) 2002 1. Bacticide, kg(RCHES) 72 in 95Yerevan, 79 which80 82acts as105 in 891999, to75 1,494,1001077 1107 m2 (2,670- houses - 2. Temephos, kg 150 67,5 - - 3. Kerosene, kgthe national 8,5 malaria reference 0,3center. 0,7 and2,5 3,467 2 animal 3,5 0,7 shelters - in - six 4. Gambusia, ha 62,5 65,8 92 81 158,9 150 727 188,8 740 758,37 1380,1 1778,1 2 SubstancesFor each used case for oftreatment malaria, of some the premisesblood districts)(square mater) in 2000 in and1991-2002 to 233,661 m N Substance nameslides 1991 1992and 1993 standardized1994 1995 1996 (4371997 houses1998 and1999 2182000 animal 2001 shelters2002 1. Clorophos, kg 480 385 357 391 400 175 233 - - - - - 2. α-citrol, kg epidemiological - - -information - - are- in -five districts)- 70,6 in13,6 2001. - In 1998,- 3. Solfac, kg referred - to- the- RCHES- - for- about- 56280,6 ha of435 anopheline 677 - breeding508 Distribution of mosquito nets in 2001- 1400 m2 microscopicDistribution confirmation of bed-curtains of Ò Êá in 2001-/ sites, number the 1000 closest to the malaria foci, fcHe’S Cleaning diagnosisof Collectory Drainage netand in 1998-2002were –treated 1072,4 km with B.t.i. In 1999, 1. Cleaning of 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 Collectory epidemiological analysis (using Epi larvicide treatments covered a Drainage net km Info software). - - The- RCHES- - have- surface38,3 344,2 of about 145,4 125310,3 ha and130,2 of 104,0about Ditch-water surface in Endemic areas of Armenia N Water surfaceconfirmed diagnosis and analyzed Anophelogen Water150 haReserve in 2000 and of about 23 ha in data from With case Economical reports notifiedWithout Economical to 2001. TheWith Economicaltotal number ofWithout imported Importance Importance Importance Economical RCHES from 1988 to 2000. and indigenous malariaImportance cases that 1320 4306,7 ha 904,2 1136,0 100,8 1026,0 occurred in Armenia from 1994 to RESULTS 2002 is reported in Table 2. The A three-year indoor spraying distribution by region and district of campaign was carried out in all the all indigenous malaria cases in malaria foci of Armenia in 1998-2000 Armenia between 1998 and 2002 is
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reported in Table 1. All cases were in two new districts of the Armavir due to P. vivax. Region, On the whole, malaria foci were reported in 15 villages In 1998, 1,156 malaria cases were belonging to the regions of Ararat confirmed microscopically, 614 of and Armavir. which imported and 542 contracted locally. All indigenous cases In 2001, 48 malaria cases were occurred in the Ararat valley (Turkey confirmed, 35 of which were border) (Fig.l); most of them (93.3%) imported and 13 indigenous. occurred in the Ararat region, in Majority of events (90.9%) occurred particular in the city of Masis and in in the Region of Ararat, in particular some villages close to the city. Some in the district of Vedi. cases (6.5%) occurred in the Armavir region and a single case in the DISCUSSION outskirts of the capital city, Yerevan. In Armenia, malaria surveillance has On the whole, malaria foci were been improved to ensure timely reported in 32 villages and 3 urban detection of all suspected cases. areas (Yerevan, Masis and Ararat). Hospitalization (in no later than 1-3 days) for at least 5 days, subsequent In 1999, 616 malaria cases were treatment and follow up under direct confirmed, 287 of which were supervision of a physician, were imported and 329 indigenous. 91% successfully carried out. of those occurred in the Ararat region, in particular in the district of In 1998, although the total number of Masis, and 7.6% in the region of malaria cases increased in Armavir. For the first time, 5 cases comparison with 1997 (Table 2), the (1.4%) were reported outside the epidemic was successfully contained Ararat valley, in the Tavush region and a slight reduction (- 4%) of the (Idjevan district, Azerbajan border) indigenous cases was also recorded. (Fig.l). On the whole, malaria foci In 1999, the total number of malaria were reported in 45 villages and 2 cases decreased in comparison with urban areas (Masis and Ararat). 1998, with a remarkable reduction in the number of indigenous ones (- In 2000, 141 malaria cases were 40%). In 2000, a further, dramatic confirmed, 85 of which were reduction of both total and imported and 56 indigenous. indigenous cases was reported in Majority of them (68%) occurred in comparison with 1999, the the Region of Armavir, in particular indigenous cases being decreased by in the district of Armavir. For the first 84%, and in 2001-2002 the indigenous time since 1996, no indigenous cases cases continuing decrease: in 2001 were reported in Masis city and indigenous cases being decreased by District, yet 30 cases were reported 42.9% in comparison with 2000, and
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: in 2002 by 59.4% in comparison with area, very good results have been 2001 (Table 2). achieved also by environmental management activities (drainage). The five-year RBM program, carried Resolving the problem of “urban out in 1998-2002, has certainly malaria” by reducing mosquito- achieved a good result. Nevertheless, breeding sites may be more although in 2000 no indigenous acceptable economical and safer than malaria cases occurred in the district indoor spraying operations. of Masis, the most involved since 1996, some cases were reported in The positive results achieved by the two districts of the Armavir region, RBM program should be improved where indigenous malaria and consolidated to meet current transmission was never reported in needs and achieve sustainable the past years (Table l). Therefore, a control of malaria in Armenia. potential situation of risk for malaria Human capacity development / transmission is still present in all the training and re-training of general Ararat valley and, likely, in other practitioners, parasitologists, areas of the Country, because of the entomologists, laboratory presence of the main vector An. technicians, spray men, should be sacharovi (7). In these areas spraying carried out regularly. The operations should be continued for introduction of primary health care at least three years in order to reduce strategy in the Republic of Armenia the abundance of that highly must be considered the essential endophilic vector. component of health care system reforms. Since the malaria On the other hand, it should be epidemiological situation has stressed, that more than 1/3 of the recently changed dramatically, it is indigenous malaria cases (35%) necessary to undertake a new reported in Armenia in 1998-99 stratification of the malaria risk in the occurred in the city of Masis, in Armenian territory. It is necessary to particular in a peripheral area very make a new model of parasitological close to extensive anopheline services- including elements of breeding sites. Where the scarce epidemiological geography and with presence of cattle can not turn away rationalization of system of mosquito bites from man (7). In this epidemiological control in Armenia.
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References 6. Pirumov, H.I., Kazanchan S.M., 1. Armenia- country update - January, Balasanian M.A.. On cases of 4-days 2001 malaria after blood transfusion. 2. Davidiants V., Manrikian M., Meditsink. Parazitol. Parazitar. Bolezni Sayadian G., Paranakian A., Davtian 4: 7-9,1983, [In Russian]. B... Epidemic Malaria transmission 7. Romi R., Boccolini D., Hovanesyan - Armenia 1997. Morbidity Mortality L, Grigorian G., Di Luca M., Weekly Report, July 3, 47 (25): 526- Sabatinelli G. Anopheles sacharovi 528, 1998. (Diptera:Culicidae): a reemerging 3. Ejov M., Davidiants, V., Avetisyan malaria vector in the Ararat Valley L. On the question of malaria of Armenia. J. Med. Ent. in press. control strategies in Armenia. Jornal 2001. of Health Sciences management and 8. Sabatinelli G. Determinants in Public Health 2, 2001, 111-114. malaria resurgence in the former 4. Davidyants V. Roll Back Malaria: USSR. Giornale Ital. Med. Trop. 4: (3- Country report. World malaria 4): 53-62. 1999. Congress, Washington, USA, 2001. 9. Sabatinelli G., Jorgensen P. Malaria 5. Mkrtchyan A., Avetisyan L., in the WHO European Region Davidyants V. “Malaria. Monograph, (1971-1999). Eurosurveillance 6(4): Yrevan, 2002,192pp. [In Armenian]. 61-65, 2001.
“veqtor-kontrolis” meTodiT ganxorcielebuli zomebi, mimarTuli malariis xelmeore afeTqebis winaaRmdeg somxeTSi
lilit avetisiani
statiaSi gaanalizebulia somxeTis mosaxleobaSi malariis gavrcelebis problemebi, am paTologiasTan dakavSirebuli epidemiologiuri situacia 1945 wlidan dRemde.
rogorc avtori aRniSnavs, somxeTSi es daavadeba iseve, rogorc mTlianad kavkasiis regionSi 80-wlebisaTvis TiTqos mTlianad daZleuli iyo, miuxedavad imisa, rom mezobel TurqeTSi da gansakuTrebiT iranSi epidemiologiuri situacia zedmiwevniT daZabuli rCeboda.
somxeTis, rogorc damoukidebeli saxelmwifos, saerTaSoriso urTierTobebis mkveTri gafarToeba, qveynis moqalaqeTa Tavisufali gadaadgileba, gansakuTrebiT axlo aRmosavleTis qveynebSi, avtoris azriT, malariis xelmeore afeTqebis erT-erTi ZiriTadi mizezia.
daavadebis Semdgom gavrcelebas xels uwyobs qveyanaSi arsebuli arakeTilsaimedo ekologiuri situacia, profilaqtikuri programebis daufinansebloba da sxv. mdgomareobis gamosworebis mizniT somxeTSi ramdenime welia xorcieldeba profilaqtikis e.w. “veqtor-kontrolis” meTodis danergva, rac avtoris azriT, uaxloes droSi dadebiT Sedegebs moitans. 146