PARTIAL INTEGRATION OF MALARIA CONTROL IN

PROGRESS OF PARTIAL INTEGRATION OF MALARIA CONTROL WITH OTHER VECTOR BORNE DISEASES CONTROL IN NORTHERN THAILAND

Wannapa Suwonkerd1, Robert Vryheid2 and Nantawan Suwannachote1

1Vector Borne Disease Section, Office of Disease Prevention and Control No.10, Chiang Mai, Thailand; 2Graduate School of Public Health, San Diego State University, California, USA

Abstract. Thailand partially integrated the malaria program into the provincial and local Public Health system starting in 2003 by adding it to the control of other vector borne diseases and by transferring some activities to the Public Health Department. This study evaluates the results of this transfer on 8 high malaria incidence districts of Mae Hong Son and Chiang Mai Provinces. Indicators were measured for all community hospitals, Vector Borne Disease Control Units, (VBDU), health centers (HC), malaria clinics, and malaria posts in 2003 and 2004 during the first two years of partial integration. The number of Vector Borne Disease Control staff decreased 1.8 - 3%, and their operational budgets decreased 25%. The VBDU staff did all the indoor residual spraying (IRS), insecticide treated net (ITN) work and entomology surveys, they took 80.6% of the blood films, and treated 72% of the patients, while Public Health system did the remainder. The Annual Parasite Incidence (API) (1 - 10/1,000) and IRS coverage (88 - 100%) remained adequate in most areas during the first years after partial integration, but the API increased (to 31.6 - 57.6/1,000) in some populations. The percentage of insecticide treated bed net coverage was adequate in Mae Hong Son (95.4%), but inadequate in Chiang Mai (52.2%). Early diagnosis and prompt treatment (4 - 23 days), hospitals report- ing disruption of anti-malarial drugs (3 of 7), and health centers having all needed equipment, training, and drugs for malaria diagnosis (9%) remain inadequate. If the program is allowed to diminish, malaria could spread again among the popu- lation. Integration of antimalarial activities into the general Public Health system has only been partially successful. We recommend the integration process and results should be monitored and evaluated to find and mitigate problems as they occur, and modify the integration process if needed. Key words: malaria, vector borne disease, control program, partial integration

INTRODUCTION Correspondence: Wannapa Suwonkerd, Vector The 1978 International Conference on Borne Disease Section, Office of Disease Pre- vention and Control No. 10, 18 Boonruangrit Primary Health Care (Trigg and Road, Chiang Mai 50200, Thailand. Kondrachine, 1998) recommended inte- Tel. +66 (0) 53 221529 ext 216; Fax: +66 (0) 53 gration of malaria control into primary 212389 health care systems (PHC). The 1986 E-mail: [email protected] WHO Expert Committee on Malaria, 18th

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Report also recommended vertical malaria Despite successes in most malarious areas control be transferred to PHC, with train- of China, PHC systems were insufficient ing and supervision by malariologists to control malaria well in some areas (Li et (WHO Export Committee on Malaria, al, 1995). In some countries, high malaria 1986). The 1992 WHO Global Ministerial transmission occurred when using the Conference on Malaria in Amsterdam, is- control strategy, allowing a resurgence of sued the World Declaration on the Con- malaria, such as in India. Some experts trol of Malaria, that adopted control as the recommended continuing to have a core main strategy for malaria, with integration of specialized malaria staff, especially for into PHC (Kidson, 1992; Trigg and vector control (Rashid, 1987; Dhingra et al, Kondrachine, 1998; WHO Export Commit- 1997; Sharma, 1999; Kroeger et al, 2002). tee on Malaria, 2000). Even in countries experiencing sufficient The control strategies obtained good malaria control progress to potentially results in parts of several endemic coun- eliminate indigenous transmission in some tries, (Mabaso et al, 2004; Sharp et al, 2007; areas, the WHO recommended a core WHO, 2008). Control programs were group of malaria experts organize the ver- plagued with the same operational prob- tical program to eliminate malaria (WHO, lems as eradication programs (Sharma VP, 2007). 1996; WHO, 2008). Cost-saving in many In this international context of simi- control programs resulted in decreased lar problems occurring in several coun- indoor residual spraying (IRS), leading to tries, this study examines the progress to- increased malaria in the 1990s (Roberts ward transferring malaria activities into et al, 1997). the PHC system in areas of northern Thai- When the PHC integration policy was land. Malaria control in Thailand com- proposed, some doubted the feasibility of menced in 1950s with impressive reduc- transferring malaria control activities to tions in morbidity and mortality. Trans- general PHC, because in many countries mission, however, is still ongoing, particu- PHC was not yet strong enough to handle larly along international borders and in the malaria control (Bruce-Chwatt, 1983). forest and forest fringe where the local Countries with effective PHC had a de- vectors are present. Only slow progress crease in malaria when malaria control in malaria control has been achieved in was integrated with PHC, such as in China these core areas, in spite of continuous case (Tang et al, 1991; Luo et al, 1996). Several and vector management implemented for Southeast Asian countries have integrated decades. The ecology of the vectors, diffi- malaria vertical programs into PHC, with cult travel, language and ethnic diversity, treatment transferred to PHC, but malaria and genetic polymorphism of the people vector control teams continued their work compound these problems (Malikul, 1988; and combined it with other insect-borne Charoenviriyaphap, 2000). disease vector control, such as dengue Over its history, Thailand’s malaria (Rashid et al, 1987). program policies have been altered several As predicted, some PHC systems times to fit changes in the malaria situa- could not handle the malaria control in tion affecting control and reporting activi- addition to the other diseases they were ties. These paralleled international policy already having difficulties controlling. changes described above, since Thailand

1298 Vol 41 No. 6 November 2010 PARTIAL INTEGRATION OF MALARIA CONTROL IN THAILAND participates in international malaria infor- do this, we assessed malaria control pro- mation exchange, and made the strategy gram indicators of processes for a) vector changes simultaneously with other coun- control and prevention and b) malaria pas- tries. sive case detection activities, impacts, Thirty to fifty years ago the Malaria malaria prevention, disease management, Division provided almost all the malaria and health sector development. services in outlying rural areas. These in- cluded active case detection by malaria MATERIALS AND METHODS workers going to houses, passive case de- tection by Malaria Clinics and trained vol- Chiang Mai and Mae Hong Son prov- unteers, and vector control by malaria inces were selected because they have the workers doing IRS and helping people dis- highest reported malaria cases in northern tribute insecticide treated mosquito nets Thailand. Two of Mae Hong Son’s 7 dis- (ITN). Later, the general Public Health tricts (Mae Sariang and Sop Moei), and 6 system gradually expanded its operations of Chiang Mai’s 24 districts (Chiang Dao, into these areas, mainly by establishing , Wiang Haeng, Mae Ai, Omkoi and hundreds of Health Centers offering pre- ) were selected because they ventive and therapeutic services for a wide had the highest malaria incidence of all the range of diseases. The Malaria Division, districts in the 2 provinces (Fig 1). All the Ministry of Public Health (MOPH), started community hospitals and VBDU were se- doing work to prevent dengue and filari- lected at the district level and all the health asis, and changed its name to the Bureau centers (HC), malaria clinics and malaria of Vector Borne Diseases (BVBD). In re- posts were included at the community cent years, hospital and health center staff, level. vector borne disease control staff and vol- unteers, have obtained blood films from Several indicators were studied retro- patients suspected of having malaria. One spectively or cross-sectionally at the com- of the main activities of Vector Borne Dis- munity, district and provincial levels. ease Control Unit (VBDU) staff is IRS and During the integration process of transfer- ITN work with villagers and Public Health ring work from the VBDU staff to the Pub- staff. The MOPH is gradually phasing out lic Health staff, both sets of agencies con- the VBDU staff, letting them retire one by tinued to record and report all activities, one, and not hiring replacements. Accord- so these indicators provided reliable data. ing to plan, general Public Health system 1) Work transfer indicators measured staff will eventually take responsibility for the activities conducted by the VBDU staff, IRS and ITN, but thus far, they have relied and the Public Health staff, including on VBDU staff to do this. blood films taken from suspected cases, Since this integration process is par- blood films microscopically examined, tially completed, its progress must be patients treated, entomology surveys evaluated. Therefore, the objectives of this done, houses and farm huts sprayed and study were to determine how partial inte- bed nets treated. This also included the gration is positively or negatively affect- number of VBDU personnel in the study ing malaria control processes and out- areas, and the budgets of those offices. comes and to identify activities or areas 2) Process indicators were vector con- which ought to be modified. In order to trol and prevention activities. We evalu-

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N

Wiang Haeng Chiang Dao

Mae Ai

Fang

Mae Hong son Thailand Chai Prakan

Chiang Mai

Mae Sariang Sop Omkoi Moei

Fig 1–Locations of the study sites, Sop Moei and Mae Sariang in Mae Hong Son; Omkoi, Wiang Haeng, Chiang Dao, Fang, Mae Ai and Chai Prakan Districts in . The white colored areas were not included in this study. ated vector control and prevention activi- Households questionnaire survey (MHS) ties carried out compared to those of informant knowledge, attitudes and planned. These included households and behaviors toward malaria disease, mos- farm huts protected by IRS, and distribu- quito net ownership and use and their in- tion of ITN. Data regarding malaria con- formed consent. trol activities were obtained from VBDU 5) Disease management indicators for 2003 and 2004 in order to determine were: a) early diagnosis and prompt treat- the percentages of activities carried out ment (EDPT), the mean period from symp- versus those planned, divided by the tom onset to treatment, collected from the households, farm huts, and populations district VBDU routine activities; and b) protected. percentages of health facilities having 3) Impact indicators measured the malaria diagnostic equipment and capa- impact on malaria, calculated by the An- bilities to do malaria microscopy diagno- nual Parasite Incidence rate (API per 1,000 sis and provide treatment correctly accord- population), obtained from the routine ing to national policies. Data were col- activity reports of the VBDU, and annu- lected using a structured health facility ally summarized as morbidity rates by questionnaire. districts and provinces. 6) Health sector development indica- 4) Malaria prevention indicators tors evaluated percentages of health facili- evaluated households having at least one ties reporting no disruption of stock of ITN, and average number of persons per antimalarial drugs for more than one week net. Data were collected using a Malaria during the previous three months, col-

1300 Vol 41 No. 6 November 2010 PARTIAL INTEGRATION OF MALARIA CONTROL IN THAILAND lected in the same structured health facil- The impact indicator ity questionnaire and interview. The Annual Parasite Incidence (API per 1,000) in our routine epidemiological RESULTS data has been systematically reported separately for Thai citizens and non-per- The work transfer indicators manent foreign patients. This is used to The work transfer indicators showed identify foci and communities needing the VBDU staff did all the IRS and ITN additional investigation, vector control, work. They slowed and then stopped do- and case detection and treatment. In Mae ing adult mosquito surveys, but continued Hong Son Province the API decreased in doing larvae surveys in 90 - 100% of tar- Thai residents from 14.2 to 10.0 from 2003 get villages, but the Public Health staff did to 2004. In Mae Sariang the API decreased not do this. Among the blood films taken from 9.04 to 6.6 from 2003 to 2004. In and microscopically examined, 80.6% Chiang Mai Province, the API decreased were done by VBDU staff and volunteers, from 1.11 to 1.08 from 2003 to 2004 among and 19.4% by Public Health staff. Seventy- Thai residents. However, among Thai resi- two percent of the patients were treated dents this indicator increased from 2003 by VBDU staff, and 28.0% by Public Health to 2004 in Wiang Haeng (24.21 to 31.63), staff. The number of VBDU personnel in and deceased slightly in Chiang Dao (18.76 the study areas decreased by 1.8-3% dur- to 15.68) districts (Table 1). In contrast, ing the study. The operational budget of many non-permanent foreign residents the VBDU decreased by >25% so the re- had high, increasing APIs, rising from maining personnel were able to do less 47.17 to 50.68 in Sop Moei, and 28.10 to field work. They were changing their roles 57.46 in Mae Sariang Districts of Mae Hong from implementing full disease control Son, from 2003 to 2004. Over a longer pe- operations to technical support and coach- riod from 1999 to 2004, the API among ing of Public Health personnel. Thai residents decreased in Mae Hong Son Process indicators Province from 25 to 10, and in Chiang Mai The IRS and ITN activities planned and Province from 2.38 to 1.08. finished on time in the first two years of The malaria prevention indicator partial integration, 2003 and 2004, increased The proportion of households having in some areas, and changed little in some ITN, was 95.3% in Mae Hong Son, and areas. The percentages of planned house- 52.2% in Chiang Mai. The average num- holds protected by IRS increased signifi- ber of persons per net was 2.05 in Mae cantly in Mae Hong Son (77.98% to 88.01%) Hong Son, and 2.52 in Chiang Mai. Two (p < 0.001), while there was little change areas of Chiang Mai Province had espe- among Mae Hong Son farm huts (100.0% cially low percentages of households with to 101%), Chiang Mai households (95.9% nets: 25% in Ban Pa Kha (), to 94.3%), and Chiang Mai farm huts (100% and 29% in Ban Huoy Poo Luong (Omkoi to 99.9%). However, number of ITN dis- District). tributed increased significantly from 91.3% to 96.8% in Mae Hong Son (p < 0.001), and The disease management indicators 89.3% to 98.4% in Chiang Mai (p < 0.001), Early diagnosis and prompt treatment comparing 2003 and 2004, respectively. (EDPT), the mean period from symptoms

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Table 1 Annual Parasite Incidence (API per 1,000) collected from the routine epidemiology reporting system, Vector Borne Disease Control Center (former, Malaria Center). Annual Parasite Incidence/1,000 populationa Province District 2003b 2004c

Chiang Mai (whole province) 1.11 1.08 Chiang Dao 18.76 15.68 Omkoi 6.34 3.67 Wiang Haeng 24.21 31.63 Fang 2.83 2.87 Mae Ai 2.81 3.44 Chai Prakan 1.35 2.11 Mae Hong Son (whole province) 14.20 10.04 Sop Moei 9.61 9.38 Mae Sariang 9.04 6.6 aThai-permanent resident: Thai citizens b2003, October 2002 to September 2003 c2004, October 2003 to September 2004

Table 2 Availability of malaria diagnostic and treatment supplies and facilities obtained by questionnaire and interviews, from 73 health sectors in study sites in Mae Hong Son and Chiang Mai Provinces.

General district Health Malaria clinic hospital (7) center (66) (16) Resources CM (5) MHS (2) CM (49) MHS (17) CM (12) MHS (4)

Human resources Microscopist (available) 5 2 4 4 12 4 Equipment Microscope 5 2 31 9 12 4 Glass slide 5 2 30 9 12 4 Malaria staining reagent 5 2 2 4 12 4 Malaria treatment guidelines 5 2 7 6 12 4 Thermometer 5 2 31 9 10 2 Malaria rapid diagnostic kit 0 0 0 0 0 1 Anti-malaria drugs (disruption more than one week) Chloroquine tablets 0 0 38 9 1 0 Mefloquine tablets 2 1 15 11 1 0 Quinine tablets 0 0 14 13 4 3 Quinine injection 0 0 15 17 None None Artemisinin derivative tablets 2 1 14 12 5 1 MHS, ; CM, Chiang Mai Province; None, Not available because the ma- laria clinic was not allowed to provide injections to patients following National Malaria Control Program policies.

1302 Vol 41 No. 6 November 2010 PARTIAL INTEGRATION OF MALARIA CONTROL IN THAILAND until treatment, ranged from 4 to 23 days. out only some testing and treatment of In Mae Sariang District, Mae Hong Son malaria patients, along with a large vol- Province, this decreased: 4.26, 3.58 and 1.88 ume of work for many other diseases. days in 2002, 2003 and 2004. In Chiang Mai After the dwindling number of VBDU staff Province there was little change. The stop doing entomology, IRS, and ITN work length of time even increased in some dis- in the future, will public health staff carry tricts, such as Fang District (11.67 to 14.14), out these duties as planned or not ? Car- and (7.51 to 11.11). rying out these duties inadequately could The percentages of health facilities result in an increase in malaria cases as has able to do malaria diagnosis varied. happened in other countries. Among the 7 general district community Process indicators show the VBDU hospitals located in the study area (2 in had high coverage of IRS and ITN. The Mae Hong Son and 5 in Chiang Mai), all staff’s diligence was shown in their attain- had malaria diagnostic equipment (light ing higher coverage in farm huts than in microscope, glass slides, staining facilities, households, since more transmission oc- etc), and personnel capable of making a curs in huts, but they require arduous correct diagnosis and treatment. None had walking to reach. The numbers of ITN rapid malaria diagnosis test kits. How- used increased in 2004 in both Chiang Mai ever, only 40 of 66 (60.6%) HC had micro- and Mae Hong Son. High IRS and ITN cov- scopes and only 8 had both microscopes erage also reflects the public’s willingness and skills (12.1%). Only 13 (19.6%) HC had to cooperate with the malaria program. national malaria drug treatment guide- Evaluation of malaria incidence from lines. No HC had rapid malaria diagno- 1977- 2002 indicates a steady reduction in sis tests (Table 2). malaria incidence in northern Thailand, with an average decline of 6.4% per year (Childs The health sector development indicator et al, 2006). Our data shows the impact indi- Among the district hospitals, 3 out of cator, disease burden, is decreasing among 7 reported disruption of mefloquine and Thai residents. But it is increasing among artemisinin derivative tablets (42.8%). non-permanent foreigners in some areas, However, among the 66 HCs, 47 (71.2%) most of whom are ethnic groups from lacked chloroquine, 27 (40.9%) lacked qui- , or from Lao PDR or China. In- nine, and 26 (39.4%) lacked mefloquine fection rates are higher along the Thailand- and artimisinin (Table 2). Myanmar border, including Chiang Mai Only 6 (9.0%) of the 66 HCs had the and Mae Hong Son Provinces.The migra- ability to diagnose and treat malaria: a mi- tion of infected individuals over interna- croscope, equipment, a skilled microsco- tional borders is considered a significant pist, treatment guidelines and no disrup- source of malaria transmission in Thailand tion of medicines. (Somboon et al, 1998; Charoenviriyaphap, 2000). This reveals the currently decreas- DISCUSSION ing case numbers could increase if malaria is allowed to spread among immigrants Work transfer indicators show VBDU and across borders. personnel carried out reduced entomology Several indicators revealed inad- activities, and almost all the IRS and ITN equate protection. The malaria prevention work, and Public Health personnel carried indicator, households and people with bed

Vol 41 No. 6 November 2010 1303 SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH nets, was adequate in Mae Hong Son, but indicators. We recommend health admin- not in Chiang Mai. Disease management istrators move cautiously toward the new indicators (early diagnosis and prompt strategy of integration into the public treatment, and the ability of the health fa- health services, and be prepared to change cility to diagnose malaria) were inad- directions or stop if the integration pro- equate in many facilities, and urgently cess encounters more problems. need improvement. Health sector devel- opment and anti-malaria drug disruption ACKNOWLEDGEMENTS had logistical problems which could have been caused by budget constraints or their This study was supported financially remote location. by WHO SEARO, Delhi, India, Grant # 02412. Currently, malaria is under control, with morbidity and mortality at fractions of their levels decades ago. But several REFERENCES weaknesses in the health system, the incom- Bruce-Chwatt LJ, Malaria control primary plete transfer of work to Public Health health care : or the art of sequaring the agencies, and vulnerabilities in the social article. Bull Soc Pathol Exot Filiales 1983; and ecological system, could result in a “re- 76: 477-85. bound epidemic” of malaria (WHO, 2008). Charoenviriyaphap T, Bangs MJ, Ratanathum Malaria transmission is out of control in S. Status of malaria in Thailand. Southeast most of eastern Myanmar. People are car- Asian J Trop Med Public Health 2000; 31: rying drug-resistant malaria across the 225-37. border daily, and Thailand’s hills and for- Childs DZ, Cattadori IM, Suwonkerd W, ests are optimum habitats for two efficient Prajakwong S, Boots M. Spatiotemporal vectors, An. dirus s.l. and An. minimus s.l. patterns of malaria incidence in northern (Suwonkerd et al, 2002, 2004; Overgaard Thailand. Trans R Soc trop Med Hyg 2006; et al, 2003). When malaria enters Thailand’s 100: 623-31. rural communities, the Public Health sys- Dhingra N, Joshi RD, Dhillon GPS, Lal S. En- tem may not be able to find and stop it, be- hanced malaria control project for World cause many Health Centers cannot diag- Bank support under National Malaria J Commun nose and treat malaria. A positive step was Eradication Program (NMEP). Dis 1997; 29: 201-8. made after this study was carried out, by creating a system of Malaria Posts, with Kidson C. Global malaria challenge: the Amsterdam Summit [Editorial]. Southeast villagers supplied and trained to perform Asean J Trop Med Public Health 1992; 23: malaria rapid tests and treatment. 635-40. This study shows the transfer of ma- Kroeger A, Ordonez-Gonzalez J, Avina AI. laria prevention and treatment from the Malaria control reinvented: health sector VBDU to the Public Health system has reform and strategy development in Co- only been partially successful. In order to lombia. Trop Med Int Health 2002; 7: 450-8. compare outcomes and epidemiology over Li H-F, Xu B-Z, Webber R. Primary health care: periods with naturally fluctuating trans- the basis for malaria control in Hubei, mission, to find or predict problems, and China. Southeast Asian J Trop Med Public to suggest mitigation methods, we will Health 1995; 26: 29-33. continue to monitor and evaluate these Luo D, Shang L, Lin X, You X. A successful

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