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Schistosomiasis remains one of the most prevalent parasitic diseases worldwide and the infection is frequently found in travelers and migrants. The European Network for Tropical Medicine and Travel Health conducted a sentinel surveillance study on imported schistosomiasis between 1997 and 2010. This report summarizes epidemiological and clinical data from 1,465 cases of imported schistosomiasis. Direct pathogen detection and serology were the main diagnostic tools applied. Of these, 486 (33%) cases were identified among European travelers, 231 (16%) among long-term expatriates, and 748 (51%) among non-European immigrants. Overall, only 18.6% of travelers had received pretravel advice; 95% of infections were acquired in the African region. On species level, Schistosoma mansoni was identified in 570 (39%) and Schistosoma haematobium in 318 (22%) cases; 57.5% of patients were symptomatic. Acute symptoms were reported in 27% of patients leading to earlier presentation within 3 months. Praziquantel was used in all patients to treat schistosomiasis. Many infections were detected in asymptomatic patients. In 47.4% of asymptomatic patients infection was detected by microscopy and in 39% by serology or antigen testing. Schistosomiasis remains a frequent infection in travelers and migrants to Europe. Travelers should be made aware of the risk of schistosomiasis infection when traveling to sub-Saharan Africa. Posttravel consultations particularly for returning expatriates are useful given the high potential for detecting asymptomatic infections.

Circumsporozoite protein (CSP) is one of the stage specific antigens, which is used for the development of vaccines and to investigate the genetic diversity in Plasmodium falciparum malaria parasite. Polymerase chain reaction was used for typing of CSP genes on 67 positive falciparum malaria patients from Sistan and Baluchistan Province of Iran. Three fragments were detected for CSP gene. Twenty, 38 and 4 samples showed 700, 750 and 800 bp fragments, respectively. Sequences of some samples were aligned and compared with P.falciparum csp gene in gene bank. While the falciparum malaria endemic region of Iran is classified in low to moderate group but, extensive polymorphism was observed in the samples that could be taken into account in designing malaria vaccine.

"nBackground: The erythrocyte binding antigen 175 kDa (EBA-175) gene is located on chromosome 7. It encodes protein that binds to specific receptor glycophorin A on the erythrocyte surface during inva­sion. It has a dimorphic nature (FCR3 and CAMP). This study was designed to determine the distribu­tion of EBA-175 alleles of Plasmodium falciparum in the southeast of Iran"nMethods: We used the nested PCR method with specific primers, which improves the two fragments of the EBA-175 gene. Sixty eight microscopically positive blood samples were collected from the in­fected falciparum malaria subjects in the southeast of Iran."nResults: In this study which marks the first one in Iran, CAMP strains (714 bp) and FCR-3 strains (795 bp) were found in 14 (37.8%) and 23 (62.2%) in the originally Iranian subjects and in 10 (32.3%) and 19 (61.3%) Pakistani infected migrants respectively. Two migrant cases (6.4%) had mix CAMP/FCR-3 infection."nConclusion: The two fragments of dimorphic EBA-175 gene were observed and the FCR-3 allele was more prevalent in Iran. There was no significant correlation between one of the EBA-175 alleles and the subject group in the mentioned region. This distributional pattern should be considered in design­ing to control P. falciparum malaria in the region.

The problem of computing optimal network tolls that induce a Nash equilibrium of minimum total cost has been studied intensively in the literature, but mostly under the assumption that these tolls are unrestricted. Here we consider this problem under the more realistic assumption that the tolls have to respect some given upper bound restrictions on the arcs. The problem of taxing subnetworks optimally constitutes an important special case of this problem. We study the restricted network toll problem for both non-atomic and atomic (unweighted and weighted) players; our studies are the first that also incorporate heterogeneous players, i.e., players with different sensitivities to tolls. For non-atomic and heterogeneous players, we prove that the problem is NP-hard even for single-commodity networks and affine latency functions. We therefore focus on parallel-arc networks and give an algorithm for optimally taxing subnetworks with affine latency functions. For weighted atomic players, the problem is NP-hard already for parallel-arc networks and linear latency functions, even if players are homogeneous. In contrast, for unweighted atomic and homogeneous players, we develop an algorithm to compute optimal restricted tolls for parallel-arc networks and arbitrary (standard) latency functions. Similarly, for unweighted atomic and heterogeneous players, we derive an algorithm for optimally taxing subnetworks for parallel-arc networks and arbitrary (standard) latency functions. The key to most of our results is to derive (combinatorial) characterizations of flows that are inducible by restricted tolls. These characterizations might be of independent interest.