• Parasites, Hosts and Diseases
• /
• 제53권1호
• /
• pp.43-49
• /
• 2015

The aim of the study was to explore the possible molecular markers of chloroquine resistance in Plasmodium vivax isolates in Thailand. A total of 30 P. vivax isolates were collected from a malaria endemic area along the Thai-Myanmar border in Mae Sot district of Thailand. Dried blood spot samples were collected for analysis of Pvmdr1 and Pvcrt-o polymorphisms. Blood samples ($100{\mu}l$) were collected by finger-prick for in vitro chloroquine susceptibility testing by schizont maturation inhibition assay. Based on the cut-off $IC_{50}$ of 100 nM, 19 (63.3%) isolates were classified as chloroquine resistant P. vivax isolates. Seven non-synonymous mutations and 2 synonymous were identified in Pvmdr1 gene. Y976F and F1076L mutations were detected in 7 (23.3%) and 16 isolates (53.3%), respectively. Analysis of Pvcrt-o gene revealed that all isolates were wild-type. Our results suggest that chloroquine resistance gene is now spreading in this area. Monitoring of chloroquine resistant molecular markers provide a useful tool for future control of P. vivax malaria.

• Parasites, Hosts and Diseases
• /
• 제52권5호
• /
• pp.557-564
• /
• 2014

The vir genes are antigenic genes and are considered to be possible vaccine targets. Since India is highly endemic to Plasmodium vivax, we sequenced 5 different vir genes and investigated DNA sequence variations in 93 single-clonal P. vivax isolates. High variability was observed in all the 5 vir genes; the vir 1/9 gene was highly diverged across Indian populations. The patterns of genetic diversity do not follow geographical locations, as geographically distant populations were found to be genetically similar. The results in general present complex genetic diversity patterns in India, requiring further in-depth population genetic and functional studies.

• Parasites, Hosts and Diseases
• /
• 제52권6호
• /
• pp.621-629
• /
• 2014

Malaria is one of the most widespread infectious diseases of tropical countries with an estimated 207 million cases globally. In India, there are endemic pockets of this disease, including Aligarh. Hundreds of Plasmodium falciparum and P. vivax cases with severe pathological conditions are recorded every year in this district. The aim of this study is to find out changes in liver enzymes and kidney markers. Specific diagnosis for P. falciparum and P. vivax was made by microscopic examination of Giemsa stained slides. Clinical symptoms were observed in both of these infections. Liver enzymes, such as AST, ALT, and ALP, and kidney function markers, such as creatinine and urea, were estimated by standard biochemical techniques. In Aligarh district, P. vivax, P. falciparum, and mixed infections were 64%, 34%, and 2%, respectively. In case of P. falciparum infection, the incidences of anemia, splenomegaly, renal failure, jaundice, and neurological sequelae were higher compared to those in P. vivax infection. Recrudescence and relapse rates were 18% and 20% in P. falciparum and P. vivax infections, respectively. Liver dysfunctions and renal failures were more common in P. falciparum patients, particularly in elderly patients. Artesunate derivatives must, therefore, be introduced for the treatment of P. falciparum as they resist to chloroquine as well as sulfadoxine-pyrimethamine combinations.

• Pediatric Infection and Vaccine
• /
• 제10권2호
• /
• pp.200-207
• /
• 2003

목 적 : 말라리아는 국내에서 1970년대 말에 소멸된 것으로 알려져 있었으나, 1993년 비무장지대에 근무하던 군인에서 첫 환자가 발생한 이후, 지속적으로 증가되어 2000년에는 4,142명, 2001년에는 2,556명, 2002년에는 1,797명의 말라리아 환자가 보고되었다. 1999년부터는 민간인의 비율이 점차 증가되고 있고, 토착형 말라리아 환자가 늘어남에 따라 국내에 존재하는 매개숙주(중국 얼룩날개 모기)에 의해 주민간에 전파될 가능성도 높아진다. 저자들은 말초혈액 도말 검사 및 말라리아 항체 검사에서 말라리아로 확진된 소아 환자 13명을 조사하여 역학적 분석 및 임상적 특성을 알아보고자 하였다. 방 법 : 2000년 1월부터 2003년 8월까지 일산백병원에 내원한 소아 환자 중 말초혈액 도말 검사 및 말라리아 항체 검사로 확진된 15세 이하의 소아 환자 13명에 대하여 의무기록을 후향적으로 조사하였다. 결 과 : 13례 모두 토착형 말라리아 감염이었고, 원인 원충은 삼일열 말라리아(Plasmodium vivax)였다. 13례 중 남아와 여아의 비율은 9 : 4이었고, 발병 당시 평균 연령은 $9.5{\pm}3.6$세였다. 지역별로는 13례 중 9례가 일산 시내였으며, 11례의 발병 시기가 6~8월로 여름에 주로 발생했다. 13례 중 2례만이 3일 주기의 발작적인 발열을 보였고 나머지 11례는 지속적인 발열 및 불규칙한 발열 양상을 보였다. 혈소판 감소증은 가장 두드러진 소견으로 13례 중 12례에서 동반되었으며, 3례에서는 범혈구 감소증을 보였다. 신생아를 제외한 12례에서 hydroxychloroquine과 primaquine을 투약했고, 이후 시행한 혈액 도말 검사상 더 이상의 원충은 발견되지 않았고 혈액학적 이상 소견 역시 호전되었다. 결 론 : 저자들이 경험한 소아 말라리아 환아는 모두 Plasmodium vivax에 의해 발병되고 일부 환아는 유행외 지역에서 발병된 것으로 보아 이 원충에 의한 토착화의 확산을 추정할 수 있었다. 또한 전형적 삼일열 말라리아의 발열 양상이 없다하여도 혈소판 감소증 소견이 동반된 발열 환아에서 이 질환을 의심하여야 하며 말라리아 항체 검사가 선별 검사로 유용한 것으로 추정된다.

• Parasites, Hosts and Diseases
• /
• 제37권3호
• /
• pp.129-143
• /
• 1999

Plasmodium vivax malaria, which was highly prevalent in the Republic of Korea, disappeared rapidly since 1970s. However, malaria re-emerged with the first occurrence of a patient in 1993 near the demilitarizd zone (DMZ), the border between South Korea and North Korea. Thereafter, the number of cases increased exponentially year after year, totaling 6,142 cases (6,249 if United States Army personnels were included) by the end of 1998. Interestingly enough, the majority of cases (3,743; 61%) was soldiers aged 20-25, camping around the northern parts of Kyonggi-do or Gangwon-do (Province) just facing the DMZ. Among 2.399 civilian cases, 1,144(47.%) were those who Provinces. The re-emerging malaria characteristically revealed a combination type of short and long incubation periods with predominance of the long type. The course of illness was relatively mild, and the treatment was successful in most patients. Vector mosquitoes are Anopheles sinensis and possibly A. yatsushiroensis. Wide-scale preventive and control measures should be operated to eradicate this re-emerging disease. It has been suggested by many authors that the initial source of the re-emerging malaria was infected mosquitoes which had flown from the northern part of the DMZ.

• Pediatric Infection and Vaccine
• /
• 제4권2호
• /
• pp.282-287
• /
• 1997

Malaria due to Plasmodium vivax had been known as an indigenous protozoan disease in Korea. However, massive use of insecticides and improvement of sanitation for several decades have led to rapid reduction of malaria incidence, then it was recognized to have been almost eradicated in recent years. However in 1993, one case was reported in Phajoo, Kyungki-do, and then, reported cases have been increasing annually. Recently we encountered one case of malaria in a 3 year old male child living in Dorim-dong, Seoul, who had never been abroad and had no history of transfusion, drug abuse, and travel to endemic area in Korea. He had characteristic fever, chill and splenomegaly and was confirmed as Plasmodium vivax malaria with peripheral blood smear finding. He was successfully treated with hydroxy chloroquine and primaquine. We report this case with brief review of related literature.

• Parasites, Hosts and Diseases
• /
• 제59권6호
• /
• pp.595-605
• /
• 2021

An understanding of the knowledges, attitudes and perceptions of different populations is key for public health policy makers. Here, a survey was performed on knowledge, attitudes, and perceptions about malaria diagnosis, prevention, control, and treatment. The 407 survey participants included both uninfected inhabitants and patients from 2 cities (Gimpo- and Paju-si) of Northern Gyeonggi-do, known as high-risk areas for vivax malaria. We used community-based study design and non-probability sampling method using the primary data. Association between variables were tested using χ²-tests. In general, the information on malaria reported by the participants in this study was unsystematic and included inaccurate details. The knowledge of malaria symptoms, identified as headache, chills and fever, was high, but the surveyed community lacks knowledge of the specific medications used for malaria treatment, with a large number of respondents having no knowledge of any form of medication. Survey questions with high correct answer rates included questions about easy treatment of malaria in Korea, the high daytime activity of malaria-borne mosquitoes, and the infection risk posed by outdoor activities. However, a large portion of the respondents was unable to provide simple medical and biological information about the disease. This study aimed to comprehensively evaluate the knowledge, attitude, and practical behavior of the surveyed community with respect to malaria and the implications reported here could be applicable to other malaria endemic areas in Korea.

• Parasites, Hosts and Diseases
• /
• 제41권4호
• /
• pp.203-207
• /
• 2003

An ELISA was developed for the diagnosis of vivax malaria using multiple stage-specific recombinant antigens of Plasmodium vivax. The DNA from the whole blood of a malaria patient was used as template to amplify the coding regions for the antigenic domains of circumsporozoite protein (CSP-1), merozoite surface protein (MSP-1), apical merozoite antigen (AMA-1), serine repeat antigen (SERA), and exported antigen (EXP-1). Each amplified DNA fragment was inserted into pQE30 plasmid to induce the expression of His-tagged protein in Escherichia coli (M15 strain) by IPTG. His-tagged proteins were purified by Ni-NTA metal-affinity chromatography and used as antigens for ELISA with patient sera that were confirmed previously by blood smear examinations. When applied to patient sera, 122 (80.3%) out of 152 vivax malaria cases reacted to at least one antigen, while no reactions were observed with 128 uninfected serum samples. We applied this ELISA to the screening of 3,262 civilian residents in endemic regions near the DMZ, which resulted in 236 positively detected (7.2%) cases. This method can be applied to serological diagnosis and mass screening in endemic regions, or can be used as a safety test for transfusion blood in endemic areas.

• Parasites, Hosts and Diseases
• /
• 제44권3호
• /
• pp.221-228
• /
• 2006

We conducted a study to compare the safety and tolerability of anti-relapse drugs elubaquine and primaquine against Plasmodium vivax malaria. After standard therapy with chloroquine, 30 mg/kg given over 3 days, 141 patients with P. vivax infection were randomized to receive primaquine or elubaquine. The 2 treatment regimens were primaquine 30 mg once daily for 7 days (group A, n = 71), and elubaquine 25 mg once daily for 7 days (group B, n = 70). All patients cleared parasitemia within 7 days after chloroquine treatment. Among patients treated with primaquine, one patient relapsed on day 26; no relapse occurred with elubaquine treatement. Both drugs were well tolerated. Adverse effects occurred only in patients with G6PD deficiency who were treated with primaquine (group A, n = 4), whose mean hematocrit fell significantly on days 7,8 and 9 (P= 0.015, 0.027, and 0.048, respectively). No significant change in hematocrit was observed in patients with G6PD deficiency who were treated with elubaquine (group B, n = 3) or in patients with normal G6PD. In conclusion, elubaquine, as anti-relapse therapy for P. vivax malaria, was as safe and well tolerated as primaquine and did not cause clinically significant hemolysis.

• Parasites, Hosts and Diseases
• /
• 제53권2호
• /
• pp.169-175
• /
• 2015

The relationship between anti-Plasmodium vivax circumsporozoite protein (CSP) antibody levels and the prevalence of malaria in epidemic areas of South Korea was evaluated. Blood samples were collected from inhabitants of Gimpo-si (city), Paju-si, and Yeoncheon-gun (county) in Gyeonggi-do (province), as well as Cheorwon-gun in Gangwon-do from November to December 2004. Microscopic examinations were used to identify malaria parasites. ELISA was used to quantitate anti-circumsporozoite protein (CSP) antibodies against P. vivax. A total of 1,774 blood samples were collected. The overall CSP-ELISA-positive rate was 7.7% (n=139). The annual parasite incidences (APIs) in these areas gradually decreased from 2004 to 2005 (1.09 and 0.80, respectively). The positive rate in Gimpo (10.4%, 44/425) was the highest identified by CSP-ELISA. The highest API was found in Yeoncheon, followed by Cheorwon, Paju, and Gimpo in both years. The positive rates of CSP-ELISA were closely related to the APIs in the study areas. These results suggest that seroepidemiological studies based on CSP may be helpful in estimating the malaria prevalence in certain areas. In addition, this assay can be used to establish and evaluate malaria control and eradication programs in affected areas.