[Diversity of Leishmania Strains Isolated from Cutaneous Leishmaniasis Patients in Turkey and its Reflection to Clinics in Mice Model]. / Türkiye'de Kutanöz Leysmanyazis Hastalarindan Elde Edilen Leishmania Izolatlarindaki Farkliliklar ve Bunlarin Fare Modeline Klinik Yansimasi.

Although asexual reproduction has been attributed to Leishmania species, genetic exchange has recently been demonstrated, which helped emerging of hybrid isolates. Situated on the crossroads between three continents, Leishmania hybrids may be present in Turkey. In Turkey, visceral leishmaniasis caused by Leishmania infantum is less common, while cutaneous leishmaniasis (CL) caused by Leishmania tropica and L.infantum could reach 2500 reported cases a year. Our aim was to investigate genetic variability of local Leishmania species and presence of hybrid Leishmania strains in Turkey. Twenty CL patients from Sanliurfa and Hatay, where only L.tropica and both L.tropica and L.infantum cause CL, respectively, were registered equally. All isolates were assessed with real-time polymerase chain reaction (Rt-PCR), isoenzyme analysis, gene sequencing, two-dimensional gel electrophoresis (2D-PAGE) and MALDI-TOF/TOFMS followed by in vivo analyses on mouse model. Identification of differentially expressed proteins was performed. These proteins were confirmed by sequence analysis. All isolates from Sanliurfa were found to be L.tropica which caused cutaneous infection in mice. However, one of 10 isolates from Hatay was found as Leishmania major which caused cutaneous infection. Five isolates were found as L.tropica with Rt-PCR and gene sequencing, one of which had one different protein from the reference L.tropica strain and caused cutaneous infection. Four of the five isolates had five different proteins compared to reference strain and caused both cutaneous and visceral infections. Remaining four isolates showed double melting curves in Rt-PCR, which were concordant with L.tropica and L.infantum. Their sequencing and isoenzyme analyses indicated them as L.infantum. They had six different proteins compared to reference L.infantum strain and caused cutaneous and visceral infections. It is concluded that the isolates with different proteins were hybrid Leishmania species. In the present study, outcomes of the proteomics, genomics, clinical manifestations and tissue tropism on animal models were evaluated together for the first time. In addition to L.tropica and L.infantum, L.major was identified as a causative agent for CL and hybrids of L.infantum/tropica were also shown to be present.

[Determination of Antimony Resistance Mechanism of Leishmania tropica Causing Cutaneous Leishmaniasis in Turkey]. / Türkiye'de Kutanöz Leysmanyazis Etkeni Leishmania tropica'da Antimon Direnç Mekanizmasinin Belirlenmesi.

World Health Organization reported that approximately one billion people are at risk in endemic areas, one million cases of cutaneous leishmaniasis (CL) and approximately 300,000 cases of visceral leishmaniasis (VL) were reported per year in the last five years. The number of deaths due to VL is reported to be approximately 20,000 per year. Approximately 2500 cases/year have been reported as CL, caused by Leishmania tropica and Leishmania infantum, in Turkey. The significant increase observed in many cities mainly in the provinces of Mediterranean and Aegean regions in cases and foci in recent years, suggests that there may be an increase in this infections in the following years as well. In Turkey, the causative agent of CL is L.tropica and meglumine antimoniate is used in the treatment of CL. We aimed to determine antimony resistance genes specific for L.tropica by comparing the gene and protein expressions of antimony-resistant and non-resistant L.tropica strains. L.tropica isolates obtained from 3 CL patients without antimonate resistance from Aegean, Mediterranean and Southeastern regions of Turkey were provided to transform into 3 resistant isolates against meglumine antimony in the laboratory conditions. Gene expression alterations by microarray method; protein profiles by two-dimensional gel electrophoresis (2D-PAGE) and relevant proteins by MALDI-TOF/TOF MS of these isolates were accomplished and compared. L.tropica isolates from 10 CL patients who did not respond to antimony therapy were analyzed for resistance to antimonial compounds and quantitative real-time polymerase chain reaction was performed to detect the expression of genes responsible for resistance development. Moreover, differences in protein expression levels in isolates with and without antimony resistance were determined by comparing protein profiles and identification of proteins with different expression levels was carried out. Enolase, elongation factor-2, heat shock protein 70, tripanthione reductase, protein kinase C and metallo-peptidase proteins have been shown to play roles in L.tropica isolates developing resistance to antimonial compounds and similar expression changes have also been demonstrated in naturally resistant isolates from patients. In conclusion, it was revealed that L.tropica strains in our country may gain resistance to meglumine antimoniate in a short time. It is foreseen that if the patients living in our country or entering the country are treated inadequately and incompletely, there may be new, resistant leishmaniasis foci that may increase the number of resistant strains and cases rapidly.

[Determination of imported malaria cases in Hatay by the use of molecular methods]. / Hatay'da yurt disi kaynakli sitma olgularinin moleküler yöntem kullanarak degerlendirilmesi.

Malaria, being among the most important diseases throughout history, is still an important public health problem among parasitic diseases due to increasing population movements with various reasons such as migration, war and travel. According to WHO data each year 300-350 million people get exposed to malaria, each year 1.5-2.7 million people die from malaria and also 40% of the world's population is still at risk for this disease. According to World Health Organisation (WHO) data, imported cases were not reported since 2013 in our country. However among imported cases Plasmodium falciparum malaria can be observed. The aim of this study wasto draw attention to the imported malaria cases increasing gradually and to the importance of the chemoprophylaxis in terms of malaria before travelling. In the study, male patients who have admitted to Hatay Province Malaria Center or Mustafa Kemal University Infectious Disease Department, ages between 25-60 years, were analyzed. All of the patients have worked abroad before. Patients were mostly from Sudan but there were also patients from endemic regions such as Africa, Nigeria, Pakistan, Mali island. The cases were evaluated according to age, gender and whether they had travel stories in Turkey or abroad. Blood samples taken from the patients were firstly prepared by thin and thick smear preparations and examined microscopically by staining with Giemsa stain method. Samples that were found positive by microscopic examination were impregnated on drying papers and genotyped using nested-PCR. Out of the 30 samples from patients who had traveled to endemic countries before, determined as positive by microscopical examination and genotyped by nested-PCR, 16 of them were identified as P.falciparum, six of them as P.vivax and eight of them as P.falciparum/P.vivax. The study suggested that malaria prophylaxis has to be applied before travelling to endemic countries, in return imported malaria has to be considered one of the first diseases in mind and people who will travel should be informed about this disease before travel.

The evolutionary history of Plasmodium vivax as inferred from mitochondrial genomes: parasite genetic diversity in the Americas.

Plasmodium vivax is the most prevalent human malaria parasite in the Americas. Previous studies have contrasted the genetic diversity of parasite populations in the Americas with those in Asia and Oceania, concluding that New World populations exhibit low genetic diversity consistent with a recent introduction. Here we used an expanded sample of complete mitochondrial genome sequences to investigate the diversity of P. vivax in the Americas as well as in other continental populations. We show that the diversity of P. vivax in the Americas is comparable to that in Asia and Oceania, and we identify several divergent clades circulating in South America that may have resulted from independent introductions. In particular, we show that several haplotypes sampled in Venezuela and northeastern Brazil belong to a clade that diverged from the other P. vivax lineages at least 30,000 years ago, albeit not necessarily in the Americas. We propose that, unlike in Asia where human migration increases local genetic diversity, the combined effects of the geographical structure and the low incidence of vivax malaria in the Americas has resulted in patterns of low local but high regional genetic diversity. This could explain previous views that P. vivax in the Americas has low genetic diversity because these were based on studies carried out in limited areas. Further elucidation of the complex geographical pattern of P. vivax variation will be important both for diversity assessments of genes encoding candidate vaccine antigens and in the formulation of control and surveillance measures aimed at malaria elimination.

Evidence for the transmission of Plasmodium vivax in the Republic of the Congo, West Central Africa.

Plasmodium vivax is not thought to be transmitted in western and central Africa, because of the very high prevalence of the red blood cell Duffy-negative phenotype in local populations, a condition which is thought to confer complete resistance against blood infection with P. vivax. There are, however, persistent reports of travelers returning from this region with P. vivax infections. To investigate whether transmission occurs in this region, the presence of antibodies specific to P. vivax preerythrocytic-stage antigens was assessed in individuals from the Republic of the Congo. A total of 55 (13%) of 409 samples tested by enzyme-linked immunosorbent assay had antibodies to P. vivax-specific antigens.

Molecular identification of Leishmania spp. isolates causes cutaneous leishmaniasis (CL) in Sanliurfa Province, Turkey, where CL is highly endemic.

Cutaneous leishmaniasis (CL) is an important public health problem in Turkey. CL has been most frequently seen in Sanliurfa. There is an expectation of increase in the population of leishmaniasis cases with the influence of Syrian refugees arriving in Turkey. In this study we aimed to diagnosis of CL and identifying of parasite from Leishmania isolates by using ITS 1 PCR RFLP. Samples were collected from 135 CL patients in Sanliurfa. After the specimens were inoculated in medium NNN, the ones which were cultures positive were cultivated in RPMI 1640 followed by PCR-RFLP. Genomic DNA was extracted phenol-chloroform procedure. Samples were examined by using ITS 1 PCR followed by RFLP analysis. Our results indicated that two species, L. tropica (132 samples) and L. major (3 samples), are responsible for cutaneous leishmaniasis in Sanliurfa. Our study is the first scientific study in which it is reported molecular analyses of cutaneous leishmaniasis cases caused by L. major in Sanliurfa in Southestern Anatolia Region. Because CL cases caused by L.major are detected in our study, it is considered that genotyping is important for diagnosis of Leishmania and following change of epidemiology.

Tuberculous sacro-ileitis: two cases and radiological findings.

Infective sacro-ileitis is due to common bacteria, 25% being tuberculosis and 10% brucellosis. Slow progression characterizes joint tuberculosis, an uncommon variant of this disease. The onset is usually insidious, and early diagnosis requires a high index of clinical suspicion. We report two cases with tuberculous sacro-ileitis which initially mimicked brucellosis infiltration. Diagnosis of tuberculosis of the sacroiliac joint was established by fine-needle aspiration of joint and radiological imaging methods such as computerized tomography, magnetic resonance and three-phase bone scan. The current diagnosis and treatment of this condition is discussed based on these cases and a literature review.

Intravitreal taurolidine against experimental Staphylococcus epidermidis endophthalmitis in rabbits.

PURPOSE: Taurolidine is a broad spectrum, non-antibiotic antimicrobial agent, not previously tested against infectious endophthalmitis. The efficacy of intravitreal taurolidine in the treatment of experimental Staphylococcus epidermidis endophthalmitis was evaluated and compared with vancomycin in a rabbit model. METHODS: The right eyes of 34 albino rabbits were infected with an intravitreal inoculum of S. epidermidis (10(5) colony-forming units/0.1 ml). The right eyes of four rabbits (group 7) were not infected and served as uninfected controls. 24 hours after inoculation of bacteria the animals were divided into the following treatment groups: group 1 (7 rabbits) received intravitreal taurolidine at 24 hours and group 2 (7 rabbits) received at 48 hours. Group 3 (7 rabbits) received vancomycin at 24 hours and group 4 (7 rabbits) at 48 hours. Group 5 (3 rabbits) received polyvinylpyrrolidone at 24 hours and group 6 (3 rabbits) at 48 hours. Clinical scoring was performed at 24, 48 and 72 hours. At 72 hours post inoculation, vitreous samples were collected for quantitative microbiological studies and then, the eyes were enucleated for histopathological scorings. RESULTS: The clinical and histopathological examinations revealed significant amelioration of inflammation in eyes treated with taurolidine and vancomycin when compared with polyvinylpyrrolidone. The eyes treated with taurolidine also had significantly lower colony forming units than the eyes treated with polyvinylpyrrolidone and taurolidine rendered many eyes sterile. CONCLUSION: Taurolidine is expected to be a potential agent for treatment of S. epidermidis endophthalmitis.

Epidemiology of hepatitis B in the reproductive-age female farmworkers of southeastern Turkey.

BACKGROUND: There are limited data on the prevalence of the hepatitis B virus (HBV) infection in the agricultural population worldwide. OBJECTIVES: This study aimed to determine the prevalence of HBV infection and associated risk factors in the reproductive-age female farmworker. MATERIALS AND METHODS: This cross-sectional study was conducted between January and April 2013 in southeastern region (SAR) of Turkey. A community-based representative agricultural sample (n = 705) from the agricultural areas of nine provinces of SAR was randomly determined by clustering method using Epi Info software. Questionnaires including demographic information and risk factors of HBV were administered to participants. The presence of HBsAg, anti-HBs, anti-HBc, and anti-HBe antibodies in blood samples were measured by ELISA. RESULTS: The prevalence of the HBsAg, anti-HBs, anti-HBc, anti-HBe antibodies, and seropositivity were 5.7%, 25.9%, 28.9%, 16.4%, and 36.7%, respectively. There was no association between the HBsAg and the size of the household, age, education level, parity, and place of birth while the prevalence of HBsAg was higher in seasonal migratory farmworkers and people living in urban areas and the prevalence of anti-HBs antibody was significantly higher in women ≥ 35 years of age, those with a high parity, and those who gave birth without the assistance of health professionals (P < 0.05). The risk for HBV infection in the seasonal migratory group was 4.3 times higher in comparison to local workers (P = 0.00; OR = 4.3; 95% CI, 2.2-8.4), with a prevalence rate of 11%. CONCLUSIONS: The monitoring of at-risk groups like seasonal migratory farmworkers is necessary to strengthen the healthcare service provided to this population.

[Is the agent of cutaneous leishmaniasis in Sanliurfa changing? First cases of Leishmania major]. / Sanliurfa'da Sark Çibani Etkeni Degisiyor Mu? Ilk Leishmania Major Vakalari.

Today, almost 2 million new leishmaniasis cases are noted annually; 1.5 million of these are cutaneous (CL), and others are visceral leishmaniasis (VL). In Sanliurfa, CL cases caused by Leishmania tropica but not by other agents such as L. infantum and L. major. L. tropica is a unique parasite species in Sanliurfa and is the causative agent of anthroponotic CL (transmitted from human to vector to human). Our aim was to report 3 new CL cases due to L. major ( 2 autochthonous and 1 imported) identified in Sanliurfa. Lesion aspiration samples taken from patients were inoculated into NNN culture. Following successful isolation in NNN, promastigotes were obtained by mass culture using RPMI + 20% FCS medium. Parasites species were identified as L. major using ITS-1 PCR-RFLP analysis. This is the first report of autochthonous CL cases caused by L. major in Sanliurfa, and it is estimated that the number of such cases will increase in this region. Public health measures should be taken for L. major infections, while researchers should plan field studies to identify the vectors and reservoirs of L. major.

[Comparison of direct microcopy and antigen casette tests for the detection of Giardia and Cryptosporidium]. / Giardia ve Cryptosporidium Tanisinda Direkt Mikroskobi ve Antijen Tarama Testlerinin Karsilastirilmasi

OBJECTIVE: The aim of this study was to compare the direct microscopy used for detection of intestinal parasites with antigen casette tests used in diagnosis of giardiasis and crypyosporidiasis. METHODS: Forty-six children who lived in the Sanliurfa Orphanage were enrolled in this study. The stool specimens were taken in the morning and examined by using native-lugol, modified formalin-ethylacetate concentration methods and cellophane tape method on the same day at the Microbiology laboratory of Harran University. Also Kinyoun-acid fast stained preparations were used for the detection of Cryptosporidium. R-biopharm Cryptosporidium/Giardia casette antigen test was used for the determinaton of giardiasis and crytosporidiasis. RESULTS: The mean age of the children enrolled in this study was 8.61±3.45 and the distribution of gender was 24 female (52.2%), 22 male (47.8%), respectively. According to stool examinations, 9 of 46 examples (19.60%) were determined as Giardia intestinalis, Cryptosporidium spp. had never been found. The result of the antigen screening casette test showed 9 of 46 samples (19.60%) were positive for G. intestinalis. Also Cryptosporidium spp. had never been found by the antigen casette test. CONCLUSION: When we compared the results of the direct microscopy and antigen casette tests, we found no significant difference between them for test reliability (p > 0.05). Antigen tests have higher sensitivity (100%) and specifity (100%) than the modified acid-fast staining technique, therefore, it is a preferred reference method . However, an experienced staff working accurately might access the same conclusion. Considering the cost of antigen tests, direct microscopic examination is cheaper, andeasier when it used by an experienced person.

A case of giant hyperkeratotic cutaneous leishmaniasis in the penis.

Cutaneous leishmaniasis is a protozoan disease caused by leishmanias, which results in deformations of the skin. Cutaneous leishmaniasis is endemic in the southeastern parts of Turkey. Cutaneous leishmaniasis is the most common form and is often observed in open regions of the body. Involvement of the penis was rarely reported. In this paper, we present a case of a giant hyperkeratotic form of cutaneous leishmaniasis in the glans penis.

Differentiation of Entamoeba histolytica/Entamoeba dispar by the polymerase chain reaction in stool samples of patients with gastrointestinal symptoms in the Sanliurfa Province.

OBJECTIVE: We aimed to diagnose amebiasis and also identify Entamoeba histolytica (E. histolytica) and Entamoeba dispar (E. dispar) in patients with gastrointestinal symptoms in an endemic region in Turkey. METHODS: Stool samples obtained from 181 patients with gastrointestinal symptoms from the Harran University Hospital of Sanliurfa were examined for the diagnosis of amebiasis by the three methods which are as follows:- In house polymerase chain reaction (PCR) targeting the 135 base pair region located on the small-subunit ribosomal RNA (SSU rRNA) gene to differentiate E. histolytica from E. dispar; and the commercial kit, RIDASCREEN® stool ELISA, that identifies Entamoeba sensu lato antigen and microscopical examination of Trichrome stained smears of stool samples. RESULTS: Positivity for E. histolytica/E. dispar complex was found to be 79 (43.6%) by microscopy versus 83 (45.9%) by PCR out of 181 stool samples. A total of 45 patients were found to be positive by the antigen detection method. PCR and microscopy were both positive in 59 samples. The number of patients infected with E. dispar (39.8%) was found to be higher than E. histolytica (3.3%) while 5 patients (2.8%) had mixed E. histolytica+E. dispar infections according to PCR results. CONCLUSION: Routine diagnosis of amebiasis by a combination of microscopy and antigen detection technique should be complemented with a PCR assay as a reference test for sensitive differentiation of both species.

A real-time ITS1-PCR based method in the diagnosis and species identification of Leishmania parasite from human and dog clinical samples in Turkey.

Human visceral leishmaniasis (VL) caused by L. infantum and cutaneous leishmaniasis (CL) caused by L. tropica and L. infantum have been reported in Turkey. L. infantum is also responsible for canine leishmaniasis (CanL) and it is widely common in the country. The main aim of the present study was to design a real-time PCR method based on the internal transcribed spacer 1 (ITS1) region in the diagnosis of all clinical forms of leishmaniasis in Mediterranean, and to identify the species directly from clinical samples. Totally, 315 clinical specimens, human/canine visceral (blood, bone marrow, lymph node) and cutaneous (lesion aspiration) samples, and 51 Turkish Leishmania isolates typed by isoenzymatic method were included in the study. For optimization, DNA samples of the 34 strains were amplified by conventional ITS1-PCR and then sequenced for designing the primers and probes, allowing the species identification. Following the validation with the isolates, the test was applied on clinical samples and melting temperatures were used for genotyping. A group of PCR products were further sequenced for confirmation and assigning the inter- and intraspecies heterogeneity. The diagnosis of leishmaniasis is successfully achieved by the new real-time PCR method, and the test identified 80.43% of human and canine VL samples as L.infantum and 6.52% as L.tropica; 52.46% of CL samples as L. infantum and 26.90% as L. tropica. In 13.04% of visceral and 20.62% of cutaneous samples, two peaks were observed. However, the higher peak was found to be concordant with the sequencing results in 96.96%, in terms of species identification. The real-time ITS1 PCR assay clearly identified the leishmanial species in 81.58% of all clinical samples. Genotypic variations of Leishmania parasites in Turkey within species and intraspecies were observed, and L. tropica is also found as causative agent of human and canine VL in Turkey.

Status of high-risk oncogenic human papillomavirus subtypes harbored in the prepuce of prepubertal boys.

OBJECTIVE: To evaluate whether the high-risk human papillomavirus (HPV) subtypes that are strongly related to cervical cancer are harbored in the prepuce of the circumcised tissue of prepubertal boys in the period just before active sexual life. METHODS: The present study enrolled 30 healthy boys (age range 4-11 years, mean age 8.1 ± 1.6) who underwent a standard circumcision procedure, with hypospadias repair in 3 patients. All prepuceal samples were studied using real-time polymerase chain reaction and grouped according to HPV subtype prevalence as groups 1 (types 16 and 18), 2 (types 31, 33, 45, 52, and 58), and 3 (types 35, 39, 51, 56, 59, 66, and 68). RESULTS: HPV DNA was reported in 25 (83.3%) of the 30 subjects. All samples showed a negative result for group 2. Although most of the positive findings were for group 3 (25 [83.3%] of 30), a positive result was reported for only 1 subject for group 1 (3.3%). CONCLUSION: The results of the present study have shown that the prepuce harbored the rarest HPV types, including types 35, 39, 51, 56, 59, 66, and 68 in preadolescence boys with a high rate (83%). These findings are in contrast to the common knowledge of HPV prevalence in adults that points to the dominance of HPV subtypes 16 and 18.

[Malaria epidemiology in Bitlis from 1998 to 2008]. / Bitlis Ili'nde 1998-2008 Yillari Arasinda Sitma Epidemiyolojisi.

OBJECTIVE: Malaria is still an important public health problem both in Turkey and the world. In this investigation, the records of patients with malaria that had been detected by the Health Directorship of Bitlis between 1998 and 2008 were examined. METHODS: The retrospective study was performed on data from the Provincial Health Directory. During this 11-year period, a total of 86,951 blood samples were taken by active and pasive surveillance. Thin and thick blood smears stained with Giemsa were examined by immersion objective under microscope. RESULTS: A total of 659 (0.75%) malaria cases were detected. Of these cases, 368 (55.84%) were male and 291 (44.16%) female. It was also observed that the positive cases were found mostly between 1998-2000 and showed an increase between May-September and an important decrease from 2001. Out of the 659 cases of malaria, 599 (90.9%) cases were indigenous, 60 (9.1%) cases were imported and in all cases the determinant was Plasmodium vivax. CONCLUSION: It is hoped that, with this study, the data will contribute to the epidemiology of malaria and its prevention in Bitlis.

Worldwide sequence conservation of transmission-blocking vaccine candidate Pvs230 in Plasmodium vivax.

Pfs230, surface protein of gametocyte/gamete of the human malaria parasite, Plasmodium falciparum, is a prime candidate of malaria transmission-blocking vaccine. Plasmodium vivax has an ortholog of Pfs230 (Pvs230), however, there has been no study in any aspects on Pvs230 to date. To investigate whether Pvs230 can be a vivax malaria transmission-blocking vaccine, we performed evolutionary and population genetic analysis of the Pvs230 gene (pvs230: PVX_003905). Our analysis of Pvs230 and its orthologs in eight Plasmodium species revealed two distinctive parts: an interspecies variable part (IVP) containing species-specific oligopeptide repeats at the N-terminus and a 7.5kb interspecies conserved part (ICP) containing 14 cysteine-rich domains. Pvs230 was closely related to its orthologs, Pks230 and Pcys230, in monkey malaria parasites. Analysis of 113 pvs230 sequences obtained from worldwide, showed that nucleotide diversity is remarkably low in the non-repeat 8-kb region of pvs230 (θπ=0.00118) with 77 polymorphic nucleotide sites, 40 of which results in amino acid replacements. A signature of purifying selection but not of balancing selection was seen on pvs230. Functional and/or structural constraints may limit the level of polymorphism in pvs230. The observed limited polymorphism in pvs230 should ground for utilization of Pvs230 as an effective transmission-blocking vaccine.

The origins of African Plasmodium vivax; insights from mitochondrial genome sequencing.

Plasmodium vivax, the second most prevalent of the human malaria parasites, is estimated to affect 75 million people annually. It is very rare, however, in west and central Africa, due to the high prevalence of the Duffy negative phenotype in the human population. Due to its rarity in Africa, previous studies on the phylogeny of world-wide P. vivax have suffered from insufficient samples of African parasites. Here we compare the mitochondrial sequence diversity of parasites from Africa with those from other areas of the world, in order to investigate the origin of present-day African P. vivax. Mitochondrial genome sequencing revealed relatively little polymorphism within the African population compared to parasites from the rest of the world. This, combined with sequence similarity with parasites from India, suggests that the present day African P. vivax population in humans may have been introduced relatively recently from the Indian subcontinent. Haplotype network analysis also raises the possibility that parasites currently found in Africa and South America may be the closest extant relatives of the ancestors of the current world population. Lines of evidence are adduced that this ancestral population may be from an ancient stock of P. vivax in Africa.

Limited polymorphism of the Plasmodium vivax merozoite surface protein 1 gene in isolates from Turkey.

The 200-kD merozoite surface protein of Plasmodium vivax (PvMSP-1) is one of the leading vaccine candidates against P. vivax malaria. However, the gene encoding PvMSP-1 (pvmsp1) is highly polymorphic and is a major obstacle to effective vaccine development. To further understand polymorphism in pvmsp1, we obtained 30 full-length pvmsp1 sequences from southeastern Turkey. Comparative analysis of sequences from Turkey and other areas showed substantially limited polymorphism. Substitutions were found at 280 and 162 amino acid sites in samples from other regions and those from Turkey, respectively. Eight substitutions were unique to Turkey. In one of them, D/E at position 1706 in the C-terminal 19-kD region, the K/E change at 1709 was the only polymorphism previously known. Limited diversity was also observed in microsatellites. Data suggest a recent population bottleneck in Turkey that may have obscured a signature for balancing selection in the C-terminal 42-kD region, which was otherwise detectable in other areas.

Analysis of naturally acquired antibody responses to the 19-kd C-terminal region of merozoite surface protein-1 of Plasmodium vivax from individuals in Sanliurfa, Turkey.

Plasmodium vivax is the second most prevalent global Plasmodium species causing malaria after P. falciparum. These two Plasmodium spp. co-exist in most endemic areas, apart from west and central Africa, which has only P. falciparum. However, southeastern Turkey is one of the exceptional regions with the sole presence of P. vivax infection, where a thorough epidemiologic survey has not been performed. Here, we report for the first time the identification of naturally acquired antibodies against the 19-kd C-terminal region of the merozoite surface protein-1 of P. vivax (PvMSP1(19)), using ELISA, from residents in the Sanliurfa region of southeastern Turkey. Among the 82 samples from patients with patent P. vivax malaria, 85% of the individuals were sero-reactive to PvMSP1(19). Particularly, 69.5% of the subjects were positive for IgM, 53.6% were positive for IgG (predominantly IgG1 and IgG3), and 7.3% were positive for IgA.