Polymorphism analysis of drug resistance markers in Plasmodium falciparum isolates from Benin.

Like most countries in sub-Saharan African countries, Benin continues to bear a heavy malaria burden. In 2014, the National Malaria Control Programme (NMCP) changed its treatment policy, and recommended the use of artemisinin-based combination therapy (ACT) as first-line treatment for uncomplicated Plasmodium falciparum cases. The study presented here was conducted to investigate the impact of current antimalarial drug resistance on the country. Molecular surveillance targeting the Pfcrt, Pfmdr1, Pfkelch13, dhfr, and dhps genes was carried out on samples from patients positive for P. falciparum malaria by microscopy, LAMP and PCR diagnostic test. Molecular analysis was performed using targeted amplicon deep sequencing (TADS). In addition, the frequency of parasites with dual deletion of the histidine-rich protein 2 and 3 genes (pfhrp2 and pfhrp3), known to be responsible of the performance of HRP-based malaria rapid diagnostic tests (HRP-RDT), was estimated. Fifty-three falciparum samples collected at the Saint Jean de Dieu hospital in Tanguiéta, Benin, were tested. No Pfkelch13 validated or candidate artemisinin partial resistant variants were identified. A marked prevalence of Asn51Ile (N51I), Cys59Arg (C59R), and Ser108Asn (S108N) mutant alleles was found in the dhfr gene, representing the most frequent genotype (64%). Five-point mutations were detected in dhps, Ile431Val (I431V), Ser436Ala (S436A), Ala437Gly (A437G), Ala581Gly (A581G), Ala613Ser (A613S) of which the third was the most common (92%). No mutation was identified in dhps Lys540Glu (K540E). The quintuple mutant genotype resulting from the combination of the dhfr triple mutant (51I/59R/108N) with the dhps double mutant 436A/437G was detected at a frequency of 30%. Low levels of mutations in Pfcrt and no mutation at codon 86 in the Pfmdr1 DNA fragment were observed, whereas a high level of Tyr184Phe (Y184F) polymorphism in the Pfmdr1 gene was found. These results could be indicative, over a decade after the implementation of ACT therapy, of the return of chloroquine-sensitive but artemether-lumefantrine resistant falciparum genotypes in Benin. There was no evidence of HRP2 and HRP3 deletions. Data from the present study support the need for routine monitoring of molecular markers of antimalarial drug resistance as part of surveillance activities aimed to make informed treatment policy decisions at the national level.

[Aetiology of intestinal parasites in a sample of students from Mozambique]. / Eziologia delle parassitosi intestinali in un campione di studenti mozambicani: breve indagine conoscitiva.

The purpose of this survey is to assess the prevalence of intestinal parasites in a population of Mozambican students. Ninety five faecal samples were collected at the three schools in Marrere, Mozambique, for a period of about one week. Observations of fresh and Giemsa-stained samples were performed at the laboratory of the Geral de Marrere Hospital; observation after concentration (FEA) was performed later at the Microbiology Laboratory of the S. Maria Nuova Hospital (Reggio Emilia, Italy). The results show a high rate of intestinal parasites among the subjects examined, supported mainly by helminths (Strongyloides stercoralis and Ancylostoma/Necator americanus), and protozoa (Dientamoeba fragilis and Giardia intestinalis). Analysis of data shows that the search for pathogenic parasites with the formalin-ethyl acetate (FEA) stool concentration technique shows higher sensitivity than the observation of fresh samples (60% vs 30%) and in some cases allows the presence of a second or third parasite to be detected. The high rate of parasitosis in endemic areas underlines the importance of lending greater attention to immigrant patients in Italy, due also to the fact that parasitosis is often found in asymptomatic forms.

[Prevalence of intestinal parasitosis in Reggio Emilia (Italy) during 2009]. / Prevalenza delle parassitosi intestinali a Reggio Emilia e provincia nel corso del 2009.

The purpose of this survey is to assess the prevalence of intestinal parasites in Reggio Emilia during 2009. We analyzed 1961 samples from 1503 subjects: a copro-parasitological standard examination was performed in 1416 of the subjects and the scotch-test in the remaining 87. Of the 1503 subjects examined, 111 (7.4%) were positive for one or more parasites. Pathogenic parasites were found in 44 subjects (39.6% of all positive subjects) and non-pathogenic protozoa were found in 67 subjects (60.4% of all positive subjects). The most commonly found species were, of the protozoa, Blastocystis hominis, Dientamoeba fragilis and Giardia intestinalis and, of the helminths, Enterobius vermicularis and Taenia Spp. This epidemiological survey shows the need to pay more attention to immigrants and travellers to endemic areas as potential carriers of major parasitic infections in the community.