Malaria epidemiology and anti-malarial drug efficacy in Guinea: a review of clinical and molecular studies

Malaria is one of the leading causes of mortality and morbidity in Guinea. The entire country is considered at risk of the disease. Transmission occurs all year round with peaks occurring from July through October with Plasmodium falciparum as the primary parasite species. Chloroquine (CQ) was the first-line drug against uncomplicated P. falciparum in Guinea until 2005, prior to the adoption of artemisinin-based combination therapy (ACT). In this review, data on therapeutic efficacy of CQ and artemisinin-based combinations reported in published literature is summarized. Against CQ, a failure rate of 27% (12/44) was reported in a study in 1992; a median failure rate of 15.6% [range: 7.7–28.3; 8 studies] was observed during 1996–2001, and 81% (17/21) of the patients failed to clear parasitaemia in a study conducted in 2007. For artemisinin-based combinations, three published studies were identified (1495 patients; 2004–2016); all three studies demonstrated day 28 polymerase chain reaction corrected efficacy > 95%. One study characterized kelch-13 mutations (389 tested; samples collected in 2016) with no evidence of mutations currently known to be associated with artemisinin resistance. The impact of the ongoing COVID-19 pandemic and widespread usage of counterfeit medicines are immediate challenges to malaria control activities in Guinea.

Life-cycle mediated effects of urbanization on parasite communities in the estuarine fish, Fundulus heteroclitus

This study examined the relationship between urbanization and parasite community structure in the estuarine fish, Fundulus heteroclitus. We measured landscape and physicochemical factors associated with urbanization at 6 sites from 4 collection periods. Concurrently, we quantified the metazoan parasite community in F. heteroclitus collected at those sites, with 105 fish studied per site during the 4 collection periods. Parasite community composition differed between sites. Variation in the prevalence and intensity of infection of two indirect life-cycle parasites, Lasiocotus minutus and Glossocercus caribaensis, were the primary parasite species that determined this pattern. Sediment potassium and aquatic osmium were the most important physicochemical factors in structuring parasite communities, and habitat dominance was the most important landscape factor. Our data supports the hypothesis that urbanization, acting at both landscape and physicochemical scales, can have a significant impact on parasite community structure. This, however, varied by parasite life history: there was little effect of urbanization on the prevalence and intensity of direct life-cycle parasites, but significant variation was dedicated for indirect life-cycle parasites. This study demonstrates how anthropogenically driven landscape change influences fine-scale parasite population dynamics.

The first detection of nematodes Ashworthius sidemi in elk Alces alces (L.) in Poland and remarks of ashworthiosis foci limitations

Ashworthius sidemi, a nematode belonging to the family of Trichostrongylidae, is a primary parasite of the Asian deer, mainly sika deer (Cervus nippon), with which it was introduced to Ukraine, as well as Slovakia, the Czech Republic and France. Migrating red deer carried this parasite from neighboring countries to Polish territory. Until now, in Poland, this parasite has been recorded in European bison, red deer, roe deer and fallow deer. As a result of post-mortem examinations of 10 elk, 2 of them from the Augustów Forest and Biebrza Marshes, A. sidemi were found in abomasa for the first time in Poland. The intensity of the invasions was 120 and 7 specimens, respectively. This finding of Ashworthius sidemi in elk indicates a further expansion of the focus of ashworthiosis in BiaŁowieża towards the north into the Biebrza Marshes and the Augustowska Forest. The growth of the elk population and their tendency for long distance migrations can contribute to the spread of the parasitosis in much greater distances than deer. On the basis of our own research and data from the literature, the current spread of ashworthiosis in Poland is discussed.

INTRODUCTION, PERMANENT ESTABLISHMENT, AND DISPERSAL IN EASTERN CANADA OF OLESICAMPE GENICULATAE QUEDNAU AND LIM (HYMENOPTERA: ICHNEUMONIDAE), AN IMPORTANT BIOLOGICAL CONTROL AGENT OF THE MOUNTAIN ASH SAWFLY, PRISTIPHORA GENICULATA (HARTIG) (HYMENOPTERA: TENTHREDINIDAE)

From 1976 to 1978, 1300 mated females of Olesicampe geniculatae Quednau and Lim were released near Quebec City during a severe infestation of the mountain ash sawfly, Pristiphora geniculata (Hartig). Both cage and open releases were made. The interactions among the mountain ash sawfly, the imported primary parasite O. geniculatae, and the indigenous hyperparasite Mesochorus globulator (Thunb.), and the effect of O. geniculatae on the host population during and after the establishment phase, are reported. In 1984, O. geniculatae was recovered from all over southern Quebec. Parasitism ranged from 6 to 94%. Concurrently, infestation levels by the mountain ash sawfly declined significantly, and since 1985, the insect has almost disappeared in Quebec. With an annual spread of about 50 km per year after successful establishment, O. geniculatae now covers an area 1000 km in diameter. No major infestation by the mountain ash sawfly has been recorded in Quebec during the past 7 years. The introduction of O. geniculatae is rated as a complete success in classical biological control.

Parasitization of Larvae of Paropsis Atomaria Ol. (Coleoptera: Chrysomelidae) in the Australian Capital Territory.

Parasites of the larvae of the eucalypt-defoliating chrysomelid Paropsis atomaria Ol. in the Australian Capital Territory, Australia, in 1975-77 included the hymenopteran primary parasite Eadya paropsidis Huddleston & Short, the hyperparasites Perilampus tasmanicus Cam. and Mesochorus sp., and the tachinids Anagonia anguliventris (Mall.) (Froggattimyia anguliventris), F. tillyardi Mall. and Paropsivora sp. For the December-January 1st-generation larvae of Paropsis atomaria in 1976-77, E. paropsidis achieved an average 49% parasitism, and the tachinids 19%; the two kinds of parasites occurred together in 18% of parasitised larvae. Planidia of Perilampus tasmanicus attacked an average of 68% of the tachinid larvae and 70% of the larvae of E. paropsidis. Mesochorus occurred only in tachinid larvae, with a mean parasitism of 35% over the season, but it was not found after early January; multiparasitism with P. tasmanicus was found in 24% of parasitised tachinids. The number of progeny of the primary parasites deposited in one chrysomelid larva rarely exceeded 5 for tachinids and 6 for E. paropsidis. This occurred whether the parasites were intra- or interspecifically competing. The exceptionally high reproductive capacity of P. tasmanicus was related to poor survival: up to 50 planidia were found inside a single chrysomelid larva, in a phoretic relationship awaiting primary parasite larvae.