[Interpretation of Criteria for Diagnosis of Toxoplasmosis].

The criteria for Diagnosis of Toxoplasmosis (WS/T 486-2015)（referred to as the Criteria） was compiled following the Management Measures for Health Criteria and GBT 1.1-2009 Standardization Working Guidelines. The Criteria is composed of six chapters, including the range of application, terms and definitions, diagnostic principle, diagnostic standard, and differential diagnosis. Four informative appendices (etiology, epidemiology, clinical manifestation, and differential diagnosis) and one normative appendix (laboratory examination) are appended. The Criteria was issued by the National Health and Family Planning Commission of the People's Republic of China through No.21 of Chinese Health Announcement in 2015. The Criteria provides for the first time technical reference for diagnosis of toxoplasmosis in medical institutions and disease control institutions.

[Cost Analysis of Dog Deworming in Echinococcosis Control Program in Daofu，Sichuan Province].

Objective: To estimate the cost of dog deworming in Daofu, Sichuan Province and analyze the factors influencing the cost, in order to provide a scientific basis for the investment for echinococcosis control. Methods: Thirty villages were randomly selected in Daofu, Sichuan Province in November 2015, according to the proportion of agricultural and pastoral areas. Data concerning the cost during each step of dog deworming were collected. The unit cost was estimated, the cost composition in each step, element, and institution were described, and the main cost-influencing factors were analyzed using the linear regression method. Results: The mean cost of dog deworming in the 30 surveyed villages was 3.76 yuan/dog-times, comprising drug cost of 0.38 yuan/dog-times, bait cost of 0.37 yuan/dog-times, drug delivery cost of 0.09 yuan/dog-times, mobilization cost of 0.19 yuan/dog-times, household deworming cost of 2.05 yuan/dog-times, faeces disposal cost of 0.35 yuan/dog-times, training cost of 0.29 yuan/dog-times, and supervision cost of 0.04 yuan/dog-times. Among the deworming steps, household deworming cost occupied the most （2.05 yuan/dog-times）; among the cost elements, labour cost had the highest proportion （2.55 yuan/dog-times）; among the different-leveled institutions, village-level cost was the most important part（2.82 yuan/dog-times）. Linear regression analysis revealed that the type of production and the distance among households were the major influencing factors. The labour price was the most sensitive factor for cost-estimation in the dog deworming activities. Conclusion: The labor cost of dog deworming is very high. Governments should increase investment according to local situations.

[Dog Fecal Contamination by Echinococcus in Cuomei County of Tibet in 2015].

Objective: To understand dog fecal contamination by Echinococcus in Lhoka Prefecture of Tibet and provide basis for development of prevention and control strategies. Methods: Survey spots were sampled around the Zhegu Village of Zhegu Town in Cuomei County of Tibet using the mechanical sampling method in May, 2015. The positions of spots, amount of dog feces, types of camps, pastures, terrains, vegetations and land cover, as well as information concerning the existence of household garbage, were recorded. The linear distance from survey spot to the center of the village was calculated. Dog feces were sampled in survey spot and examined the copro-antigen for Echinococcus contamination by ELISA. The distribution characteristics of fecal contamination were analyzed by chi-square test, Fisher's exact test, Kruskal-Wallis test and Nemenyi test. Results: Seventy-nine survey spots were selected for sampling. A total of 226 feces samples were obtained in 37 of the spots. ELISA results showed that the copro-antigen positive rate was 23.9%（54/226）, the averaged density of feces and the averaged density of positive feces were 0.317 9/100 m2 and 0.075 9/100 m2, with a maximum of 2.555 6/100 m2 and 0.555 6/100 m2 respectively. The density of feces and the density of positive feces were both higher in summer camps（0.601 9/100 m2 and 0.157 4/100 m2 respectively） than in non-camps（0.170 2/100 m2 and 0.033 1/100 m2）（χ2=18.248 4，P<0.01；χ2=15.274 3，P<0.01）. In addition, the density of feces and the density of positive feces were both higher in survey spots with household garbage（0.679 0/100 m2, 0.177 0/100 m2） than in those without household garbage （0.130 3/100 m2 and 0.023 5/100 m2）（χ2=34.634 7，P<0.01；χ2=26.109 1，P<0.01）; as well as higher in survey spots ≥10 km from the center of the village（0.403 7/100 m2, 0.107 4/100 m2） than in those <10 km（0.265 3/100 m2, 0.056 7/100 m2）（χ2=4.432 7，P<0.05；χ2=4.045 5，P<0.05）. Conclusion: The Cuomei County of Tibet is facing a serious situation of dog fecal contamination by Echinococcus. Summer camps, areas with household garbage, and districts with a ≥10 km linear distance from the village center may provide reference for determining the regions for hydatidosis prevention and control.

[Gaps on China's Engagement in Global Governance of Neglected Tropical Diseases].

In this review, we used gap analysis to find out the inadeqency of China's engagement in global elimination and control of neglected tropical diseases (NTDs). Meanwhile, important facets on which our work should concentrate and some abilities that need to be improved were proposed, in the aim to stimulate the progress of global prevention and control of NTDs.

[Implementation Situation and Application Evaluation of "Standards for Control and Elimination of Malaria"].

The application evaluation of "Standards for Control and Elimination of Malaria" was carried out in 11 epidemic provinces/autonomous regions by questionnaires, field investigation and special interviews from January to May, 2014. Two hundred and forty questionnaires were completed by the personnel from the health administrations and the institutions of disease control and prevention. The questionnaire response rate was 84% (240/285). Totally 90% participants had known and used this standards. In detail, managers from the health administration departments had a percent of 100.0% (26/26), while professionals in the institutions of disease control and prevention had a percent of 88.8% (190/214). In malaria-endemic provinces/autonomous regions/municipalities, 18 training classes of malaria control and prevention were held from January 2012 to December 2013. This standards was one of the main contents. One hundred and fifty-two pieces of suggestion and recommendation were obtained, with 84.2% (128/152) relating to personnel and supporting conditions, and 15.8% (24/152) on technical issues.

[Retrospective analysis of granted projects of the National Institute of Parasitic Disease, China CDC during 2002-2012].

In this paper, the granted projects of the National Institute of Parasitic Diseases (NIPD), China CDC, was analyzed. The results showed that from 2002 to 2012, 126 projects were granted to NIPD. 28.6% (36/126) of the projects were at the national level; 27% (34/126) were at provincial and ministrerial level. International cooperation projects and those supported by state key laboratory and enterprises accounted for 28.6% (36/126) and 15.8% (20/126), respectively. 94 projects belonged to applied researches and 32 belonged to basic researches. Most project leaders were young and middle-aged researchers with senior professional titles.

[Geographical distribution of echinococcosis among children in Qinghai Province].

OBJECTIVE: To analyze the epidemiological status of echinococcosis among children in three different zones of Qinghai Province. METHODS: B-ultrasound and ELISA were used in the survey to evaluate echinococcus infection among 6 to 15 year old children in the three zones, namely, Qinghai southern plateau, Qilian mountain-Hehuang valley and Chaidamu basin. RESULTS: The prevalence of echinococcus infection scanned by B-ultrasound and sera positive rate detected by ELISA in children were 1.5% (320/20 730) and 6.5% (1024/15 762) respectively, and the prevalence of cystic echinococcosis and alveolar echinococcosis by ultrasound were 1.0% (206/20730) and 0.6% (114/20730), respectively. The prevalence and sera positive rate were 9.5% (707/7 453) and 2.3% (269/11 618) in Qinghai southern plateau, 3.8%(289/7 544) and 0.6% (50/8 275) in Qilian mountain-Hehuang valley, and 3.7% (28/765) and 0.1% (1/837) in Chaidamu basin, respectively. The southern plateau showed the highest prevalence, with a significant statistical difference among the three areas (P < 0.01). The prevalence of alveolar echinococcosis was 1.0% (114/11 618) in the southern plateau, but no alveolar echinococcosis patients were found in other two areas. Correlation analysis showed that the prevalence increased with the altitude (r(s-e) = 0.96, P < 0.05, R2 = 0.93; r(p-e) = 0.82, P < 0.05, R2 = 0.67). CONCLUSION: The prevalence of echinococcosis among children shows an apparent geographical difference in Qinghai Province.

Strengthening capacity-building in malaria and schistosomiasis control under China-Africa cooperation: Assessing a case study of Burkina Faso.

Malaria and schistosomiasis are highly prevalent in Burkina Faso, whereas China has successfully eliminated malaria as well as schistosomiasis as a public health problem. To implement the China-Africa health cooperation initiative, a series of activities were launched since 2019 to enhance understanding and cooperation among malaria and schistosomiasis professionals in China and Burkina Faso. This study described the achievements of the First Virtual Symposium of China-Burkina Faso Cooperation on Schistosomiasis and Malaria Control. Pre- and post-test questionnaires were employed to study the knowledge changes of participants regarding malaria and schistosomiasis control and elimination, explore capacity-building priorities, and identify potential challenges. Chi-squared statistics were used to compare the differences between sub-groups, and p value < 0.05 was considered statistically significant. Participants ranked their preferences for challenges and capacity-building priorities in future cooperation. The responses of participants from both China and Burkina Faso indicated effective improvement in their general knowledge about the diseases whereas the improvement in professional knowledge on malaria and schistosomiasis was limited. The total correct response rate increased from 54.08% to 66.78%. Chinese participants had better schistosomiasis knowledge than Burkina Faso participants did, but the same result was not found for malaria. Diseases control strategies, surveillance and response system, and diagnostics techniques were identified as the top three priorities for future capacity building. Participants from China and Burkina Faso shared almost the same views about challenges except with respect to pathogens, which the former saw as a major challenge and the latter did not. The study findings will help policymakers, health managers, and researchers to understand the future cooperation between Burkina Faso and China on malaria and schistosomiasis.

[Cloning, expression and immunodiagnostic evaluation of antigen EPC1 from Echinococcus granulosus].

OBJECTIVE: To clone and express EPCl gene of Echinococcus granulosus, and investigate its immunogenicity and diagnostic value. METHODS: Total RNA was extracted from hydatid cyst protoscoleces and EPC1 gene of Echinococcus granulosus was amplified by RT-PCR. The PCR product was cloned into pGEM-T vector, and then subcloned into the prokaryotic expression vector PET28a(+). The positive recombinants were transformed into Escherichia coli BL21 (DE3), and followed by expression of the protein induced by IPTG. The recombinant protein was identified by SDS-PAGE and Western blotting, and used to establish ELISA. Serum samples from patients with cystic echinococcosis (60 cases), alve-olar echinococcosis (37 cases), cysticercosis (16 cases), clonorchiasis sinensis (7 cases), schistosomiasis japonica (4 cases) and healthy persons (33 cases) were examined. RESULTS: The recombinant plasmid PET28a-EgEPC1 was identified by restriction enzyme digestion and sequencing. SDS-PAGE result showed that the recombinant containing recombinant plasmid PET28a-EgEPC1 expressed a soluble fission protein of EgEPC1 (about M, 11 000). The protein was recognized by pool sera of cystic echinococcosis patients. The overall sensitivity and specificity of diagnosis by ELISA for cystic echinococcosis were 78.3% (47/60), and 98.3% (59/60), respectively. The cross reaction with sera of alveolar echinococcosis was 40.5% (15/37). CONCLUSION: The recombinant EgEPC1 antigen has diagnostic value in cystic echinococcosis.

Advances in research on echinococcoses epidemiology in China.

Echinococcoses are serious zoonotic diseases in China's vast, western and north-western pastoral areas that has one of the highest prevalence in the world. The two most common forms, cystic echinococcosis (CE) and alveolar echinococcosis (AE), are co-epidemic in some areas causing a grave threat to people's health and economic development. Echinococcus spp. are transmitted through domestic, sylvatic and mixed cycles involving many kinds of host. Successful transmission requires a favourable environment for the growth of the parasites and survival of their eggs, while the unique customs and religious beliefs in the endemic areas pose a challenge to the prevention and control of these parasites. Based on previous epidemiological studies, this paper reviews the particular factors affecting the transmission of Echinococcus parasites in China, with a focus on biological (parasite genotype and the species, age, sex and density of hosts), environmental (landscape and climate) and social (age, gender, ethnicity, education, occupation, life style, cultural customs, living conditions and hygiene practices of humans in the endemic areas). These three factors interact with each other and jointly determine the parasites' transmission intensity, the study of which supports the formulation of the strategies and measures that are significant for control of these infections.

Assessment of China's contributions to the Regional Network for Asian Schistosomiasis and Other Helminth Zoonoses: a questionnaire survey.

BACKGROUND: The Regional Network for Asian Schistosomiasis and Other Helminth Zoonoses (RNAS+) was established in 1998, which has developed close partnerships with Asian countries endemic for schistosomiasis and other helminthiasis in Asia. RNAS+ has provided an ideal regional platform for policy-makers, practitioners and researchers on the prevention, control and research of parasitic diseases in Asian countries. China, one of the initiating countries, has provided significant technical and financial support to the regional network. However, its roles and contributions have not been explored so far. The purpose of this study was to assess China's contributions on the supporting of RNAS+ development. METHODS: An assessment research framework was developed to evaluate China's contributions to RNAS+ in four aspects, including capacity building, funding support, coordination, and cooperation. An anonymous web-based questionnaire was designed to acquire respondents' basic information, and information on China's contributions, challenges and recommendations for RNAS+development. Each participant scored from 0 to 10 to assess China's contribution: "0" represents no contribution, and "10" represents 100% contribution. Participants who included their e-mail address in the 2017-2019 RNAS+ annual workshops were invited to participate in the assessment. RESULTS: Of 71 participants enrolled, 41 responded to the survey. 37 (37/41, 90.24%) of them were from RNAS+ member countries, while the other 4 (4/41, 9.76%) were international observers. Most of the respondents (38/41, 92.68%) were familiar with RNAS+. Respondents reported that China's contributions mainly focused on improving capacity building, providing funding support, coordination responsibility, and joint application of cooperation programs on RNAS+ development. The average scores of China's contributions in the above four fields were 8.92, 8.64, 8.75, and 8.67, respectively, with an overall assessment score of 8.81 (10 for a maximum score). The challenge of RNAS+ included the lack of sustainable funding, skills, etc. and most participants expressed their continual need of China's support. CONCLUSIONS: This survey showed that China has played an important role in the development of RNAS+ since its establishment. This network-type organization for disease control and research can yet be regarded as a great potential pattern for China to enhance regional cooperation. These findings can be used to promote future cooperation between China and other RNAS+ member countries.

[Analysis on the award-winning research achievements by the National Institute of Parasitic Diseases].

OBJECTIVE: To evaluate the predominance, characteristic and shortage of the scientific activities at the National Institute of Parasitic Diseases (NIPD), through analysis on its award-winning research achievements. METHODS: Information was collected on the award-winning research achievements by the Institute in the last 45 years. Time trend, disease category, subject, award type, award grade, award level and project property of the award-winning research achievements were analyzed by using SPSS11.0 software. RESULTS: Totally, 78 research achievements were awarded 128 times in the last 45 years. 43.6% awards were at province and ministry level; 23.1% awards were at nation level. Awards involved in schistosomiasis, malaria, and kala-azar accounted for 33.3%, 28.2% and 12.8%, respectively. As for subject, preventive medicine, pharmacy and biology accounted for 28.2%, 18.0% and 16.7%, respectively; 82.1% of the awards belonged to applied researches. CONCLUSION: NIPD has a strong capacity in scientific research. To get more achievements in future, it is essential to closely integrate the experiment research to disease control.

From parasitic disease control to global health: New orientation of the National Institute of Parasitic Diseases, China CDC.

As the only specialized institution for research and control of parasitic diseases at the national level in China for almost 70 years, the National Institute of Parasitic Diseases (NIPD) at the Chinese Center for Disease Control and Prevention (China CDC) has been instrumental in supporting the remarkable progress from high prevalence to transmission interruption or low endemicity of several diseases, lymphatic filariasis, malaria and schistosomiasis in particular. This has taken place through technical guidance, emergency response and scientific research as well as providing technical service, education, training, health promotion and international cooperation. With China's increasing involvement in international cooperation and the increased risk for (re)emerging tropical diseases in mind, the Chinese Government designated in 2017 a new Chinese Center for Tropical Disease Research to NIPD. Responding to the expanded responsibilities, the institute is scaling up its activities in several ways: from parasitic diseases to the wider area of tropical diseases; from disease control to disease elimination; from biological research to policy evidences accumulation; and from public health to global health. Based on this new vision and China's previous accomplishments in the areas mentioned, the institute is in a position to move forward with respect to global health and equitable development according to the central principles of the United Nations' Sustainable Development Goals.

A path to cooperation between China and Mongolia towards the control of echinococcosis under the Belt and Road Initiative.

Health is the core of development. Health cooperation between countries plays a pivotal role under the Belt and Road Initiative (B&R). In 2013, China launched its B&R to improve the international cooperation of which health was an important component. As one of the neglected zoonotic diseases, echinococcosis has become a public health concern and is on top of the government agenda among neglected zoonosis in Mongolia. The transmission of the disease involves animal husbandry, and its characteristics determine the prevention and control of such diseases which requires cross-sector collaboration and comprehensive prevention and control strategies. Taking echinococcosis as an entry point and adopting a 'Mongolia-led, China-supported, and results-sharing' approach to public health cooperation will not only contribute to the advancement of Mongolia's national health coverage, but also promoting China's capacity to engage in global health. In this way, it contributes to meeting the sustainable development goals, especially goal 3, target 3.3: by 2030, end the epidemics of AIDS, tuberculosis, malaria and neglected tropical diseases and combat hepatitis, water-borne diseases and other communicable diseases. This paper provides an overview on how the cooperation between China and Mongolia under the context of B&R was initiated, planned and moved forward to implementation. The experience may provide a good model and inform policy and practice for other bilateral cooperations.

Multiplex PCR and oligonucleotide microarray for detection of single-nucleotide polymorphisms associated with Plasmodium falciparum drug resistance.

Drug resistance in Plasmodium falciparum is a serious public health threat in the countries where this organism is endemic. Since resistance has been associated with specific single-nucleotide polymorphisms (SNPs) in parasite genes, molecular markers are becoming useful surrogates for monitoring the emergence and dispersion of drug resistance. In this study, a multiplex PCR (mPCR) and oligonucleotide microarray method was developed for the detection of these SNPs in genes encoding chloroquine resistance transporter (Pfcrt), multidrug resistance 1 (Pfmdr1), dihydrofolate reductase (Pfdhfr), dihydropteroate synthetase (Pfdhps), and ATPase 6 (PfATPase6) of P. falciparum. The results show that DNA microarray technology, combined with mPCR, is a promising and time-saving tool that supports conventional detection methods, allowing sensitive, accurate, simultaneous analysis of the SNPs associated with drug resistance in P. falciparum.

[Multiplex PCR for analysis of the Plasmodium falciparum drug resistance molecular markers].

OBJECTIVE: To develop a multiplex PCR protocol for amplification of five Plasmodium falciparum drug resistance related genes, thereby facilitate the rapid and high throughput analysis of the drug resistance molecular markers. METHODS: Five pairs of primers were designed according to the reference sequences by using Primer Premier 5.0 and Oligo 6.0 software. Drug resistance related genes, including P. falciparum chloroquine resistance transporter (Pfcrt), multi-drug resistance 1 (Pfmdr1), dihydropteroate synthetase (Pfdhps), dihydrofolate reductase (Pfdhfr) and sarco/endoplasmic reticulum Ca2+-ATPase (PfATPase6), were amplified by single-tube multiplex PCR using Hot Start Taq DNA Polymerase among negative controls (P. vivax, P. berghei, P. cynomolgi, Leishmania donovani, Cryptosporidium andersoni), blank control (using H2O as template), as well as P. falciparum laboratory isolates (3D7, Dd2, HB3, FCC1/HN and CMH/YN) and field samples (collected from Yunnan, Hainan of China and Myanmar). After amplification, the PCR products were analyzed by agarose gel electrophoresis. The sequencing results were aligned to the reference sequence using BLAST. RESULTS: Five expected bands at 315, 437, 514, 594 and 770 bp were obtained with no additional or nonspecific products in P. falciparum laboratory isolates and field samples. The sequencing results were identical with the reference sequence except the polymorphism sites, and exhibited more than 98.5% homology. The multiplex amplification was performed successfully starting from 0.1 ng of DNA template. No band was observed in negative controls and blank control. CONCLUSION: The present study establishes a method to amplify five Plasmodium falciparum drug resistance related genes harboring 21 SNPs by one-tube reaction. The multiplex PCR protocol showing high specificity and sensitivity is more convenient and efficient in analyzing the P. falciparum drug resistance molecular markers as compared with traditional nested PCR.

New insights on serodiagnosis of trichinellosis during window period: early diagnostic antigens from Trichinella spiralis intestinal worms.

The clinical diagnosis of trichinellosis is difficult because its clinical manifestations are nonspecific. Detection of anti-Trichinella IgG by ELISA using T. spiralis muscle larval excretory-secretory (ES) antigens is the most commonly used serological method for diagnosis of trichinellosis, but the main disadvantage is false negativity during the early stage of infection. There is an obvious window period between Trichinella infection and antibody positivity.During the intestinal stage of Trichinella infection, the ES antigens of intestinal worms (intestinal infective larvae and adults) are exposed to host's immune system at the earliest time and elicit the production of specific anti-Trichinella antibodies. Anti-Trichinella IgG antibodies in infected mice were detectable by ELISA with ES antigens of intestinal worms as soon as 8-10 days post infection (dpi), but ELISA with muscle larval ES antigens did not permit detection of infected mice before 12 dpi. Therefore, the new early antigens from T. spiralis intestinal worms should be screened, identified and characterized for early serodiagnosis of trichinellosis.

Spatial analysis of visceral leishmaniasis in the oases of the plains of Kashi Prefecture, Xinjiang Uygur Autonomous Region, China.

BACKGROUND: Kashi Prefecture of Xinjiang is one of the most seriously affected areas with anthroponotic visceral leishmaniasis in China. A better understanding of space distribution features in this area was needed to guide strategies to eliminate visceral leishmaniasis from highly endemic areas. We performed a spatial analysis using the data collected in Bosh Klum Township in Xinjiang China. METHODS: Based on the report of endemic diseases between 1990 and 2005, three villages with a high number of visceral leishmaniasis cases in Bosh Klum Township were selected. We conducted a household survey to collect the baseline data of kala-azar patients using standard case definitions. The geographical information was recorded with GIS equipment. A binomial distribution fitting test, runs test, and Scan statistical analysis were used to assess the space distribution of the study area. RESULTS: The result of the binomial distribution fitting test showed that the distribution of visceral leishmaniasis cases in local families was inconsistent (χ(2) = 53.23, P < 0.01). The results of runs test showed that the distribution of leishmaniasis infected families along the channel was not random in the group of more than five infected families. The proportion of this kind of group in all infected families was 63.84 % (113 of 177). In the Scan statistical analysis, spatial aggregation was analyzed by poisson model, which found 3 spatial distribution areas 1) Zone A was located in a center point of 76.153447°E, 39.528477°N within its 1.11 mile radius, where the cumulative life-incidence of leishmaniasis was 1.95 times as high as that in surrounding areas (P < 0.05); 2) Zone B was located in a center point of 76.111968°E, 39.531895°N within its 0.54 mile radius, where the cumulative life-incidence of leishmaniasis was 1.82 times as high as that in surrounding areas (P < 0.01); and 3) Zone C was located in a center point of 76.195427°E, 39.563835°N within its 0.68 mile radius, where the cumulative life-incidence of leishmaniasis was 1.31 times as high as that in surrounding areas (P < 0.05). CONCLUSIONS: The spatial distribution of visceral leishmaniasis-infected families was clustered. Thus, the proper use of this finding would be an improvement in highly endemic areas, which could help identify the types of endemic areas and population at high risk and carry out appropriate measures to prevent and control VL in this area as well.

[The point mutations in Pfcrt and Pfmdr1 genes in Plasmodium falciparum isolated from Hainan Province].

OBJECTIVE: To evaluate the point mutations in Pfcrt and Pfmdr1 genes in Plasmodium falciparum isolated from Hainan Province. METHODS: Nested polymerase chain reaction and restriction fragment length polymorphism were used to detect the point mutations at codon 76 of Pfcrt and at codon 86, 1246 of Pfmdr1 in P. falciparum isolates. Chloroquine resistance was measured by the in vitro microtest recommended by WHO. RESULTS: In 36 samples tested, 28 were successfully amplified for Pfcrt, 64.3% of them carried mutant allele at codon 76, 21.4% with wild allele K76 and 14.3% with mixed allele mutation. While for Pfmdr1, 3.4% isolates displayed the 86Y mutation, 89.7% with wild allele N86 and 6.9% with the mixed alleles in 29 isolates which were amplified successfully for N86Y. No point mutation in Pfmdr1 at codon 1246 was found in 13 isolates from the total 36 samples. By the in vitro test, 72.2% (26/36) showed resistance to chloroquine. The 76T and 86Y mutant alleles were present in both in vitro susceptible and resistant isolates. There was a significant difference between susceptible and resistant isolates carrying 76T mutant codon (P < 0.05), but no significant difference was found in Pfmdr1 (P < 0.05). CONCLUSION: There is a significant difference of the 76T prevalence in Pfcrt gene between the susceptible isolate and resistant one of P. falciparum to chloroquine in vitro. The Pfcrt 76T may be used as a predictive marker for chloroquine resistance surveillance.