Juan Cuadros

Imported Falciparum Malaria in Europe: Sentinel Surveillance Data from the European Network on Surveillance of Imported Infectious Diseases

Malaria continues to have a high morbidity rate associated among European travelers. Thorough recording of epidemiological and clinical aspects of imported malaria has been helpful in the detection of new outbreaks and areas of developing drug resistance. Sentinel surveillance of data collected prospectively since 1999 has begun within TropNetEurop, a European network focusing on imported infectious diseases. TropNetEurop appears to cover approximately 10% of all patients with malaria seen in Europe. Reports of 1659 immigrants and European patients with Plasmodium falciparum malaria were analyzed for epidemiological information and data on clinical features. Regional data were quite diverse, reflecting local patterns of immigration and international travel. By far, the most infections were imported from West Africa. Europeans had more clinical complications; consequently, all deaths occurred in this group. Compared with European standards, the mortality rate was low (0.6% in Europeans). Data from TropNetEurop member sites can contribute to our understanding of the epidemiological and clinical findings regarding imported falciparum malaria.

Age as a Risk Factor for Severe Manifestations and Fatal Outcome of Falciparum Malaria in European Patients: Observations from TropNetEurop and SIMPID Surveillance Data

Previous studies have indicated that age is a risk factor for severe falciparum malaria in nonimmune patients. The objectives of this study were to reevaluate previous findings with a larger sample and to find out how strongly clinical outcomes for elderly patients differ from those for younger patients. Results of adjusted analyses indicated that the risks of death due to falciparum malaria, of experiencing cerebral or severe disease in general, and of hospitalization increased significantly with each decade of life. The case-fatality rate was almost 6 times greater among elderly patients than among younger patients, and cerebral complications occurred 3 times more often among elderly patients. Antimalarial chemoprophylaxis was significantly associated with a lower case-fatality rate and a lower frequency of cerebral complications. Women were more susceptible to cerebral complications than were men. Our study provides evidence that falciparum malaria is more serious in older patients and demonstrates that clinical surveillance networks are capable of providing quality data for investigation of rare events or diseases.

Screening for Mutations Related to Atovaquone/ Proguanil Resistance in Treatment Failures and Other Imported Isolates of Plasmodium falciparum in Europe

BACKGROUNDnTwo single-point mutations of the Plasmodium falciparum cytochrome b gene (Tyr268Asn and Tyr268Ser) were recently reported in cases of atovaquone/proguanil (Malarone) treatment failure. However, little is known about the prevalence of codon-268 mutations and their quantitative association with treatment failure.nnnMETHODSnWe set out to assess the prevalence of codon-268 mutations in P. falciparum isolates imported into Europe and to quantify their association with atovaquone/proguanil treatment failure. Isolates of P. falciparum collected by the European Network on Imported Infectious Disease Surveillance between April 2000 and August 2003 were analyzed for codon-268 mutations, by use of polymerase chain reaction-restriction fragment-length polymorphism.nnnRESULTSnWe successfully screened 504 samples for the presence of either Tyr268Ser or Tyr268Asn. One case of Ser268 and no cases of Asn268 were detected. Therefore, we can be 95% confident that the prevalence of Ser268 in the European patient pool does not exceed 0.96% and that Asn268 is less frequent than 0.77%. In 58 patients treated with atovaquone/proguanil, Tyr268Ser was present in 1 of 5 patients with treatment failure but in 0 of 53 successfully treated patients.nnnCONCLUSIONSnTyr268Ser seems to be a sufficient, but not a necessary, cause for atovaquone/proguanil treatment failure. The prevalence of both codon-268 mutations is currently unlikely to be >1% in the European patient pool.

Plasmodium ovale Malaria Acquired in Central Spain

We describe a case of locally acquired Plasmodium ovale malaria in Spain. The patient was a Spanish woman who had never traveled out of Spain and had no other risk factors for malaria. Because patients with malaria may never have visited endemic areas, occasional transmission of malaria to European hosts is a diagnostic and clinical challenge.

Molecular surveillance of drug resistance through imported isolates of Plasmodium falciparum in Europe

BackgroundResults from numerous studies point convincingly to correlations between mutations at selected genes and phenotypic resistance to antimalarials in Plasmodium falciparum isolates. In order to move molecular assays for point mutations on resistance-related genes into the realm of applied tools for surveillance, we investigated a selection of P. falciparum isolates that were imported during the year 2001 into Europe to study the prevalence of resistance-associated point mutations at relevant codons. In particular, we tested for parasites which were developing resistance to antifolates and chloroquine. The screening results were used to map the prevalence of mutations and, thus, levels of potential drug resistance in endemic areas world-wide.Results337 isolates have been tested so far. Prevalence of mutations that are associated with resistance to chloroquine on the pfcrt and pfmdr genes of P. falciparum was demonstrated at high levels. However, the prevalence of mutations associated with resistance to antifolates at the DHFR and DHPS genes was unexpectedly low, rarely exceeding 60% in endemic areas.ConclusionsConstant screening of imported isolates will enable TropNetEurop to establish a screening tool for emerging resistance in endemic areas.

Molecular surveillance of the antifolate-resistant mutation I164L in imported african isolates of Plasmodium falciparum in Europe: sentinel data from TropNetEurop

BackgroundMalaria parasites that carry the DHFR-mutation I164L are not only highly resistant to sulfadoxine-pyrimethamine but also to the new antimalarial drug chlorproguanil-dapsone. The spread of this mutation in Africa would result in a public health disaster since there is a lack of effective alternatives that are both affordable and safe. Up to now, this mutation has only been described in Asian and Latin-American countries. The objective of this study was to assess the prevalence of this mutation in African isolates of Plasmodium falciparum that have been imported into Europe through travellers.MethodsTropNetEurop is a network for the surveillance of travel-associated diseases and seems to cover approximately 12% of all malaria cases imported into Europe. Within this network we screened 277 imported African isolates of P. falciparum with the help of PCR- and enzyme-digestion-methods for the antifolate-resistant mutation I164L.ResultsThe I164L mutation was not detected in any of the isolates tested.DiscussionContinuous molecular surveillance of mutations in P. falciparum, as it is practised within TropNetEurop, is an essential tool for the understanding and early detection of the spread of antimalarial drug resistance in Africa.

El laboratorio de microbiología ante las enfermedades parasitarias importadas

Imported parasitosis represents an increasingly frequent diagnostic challenge for microbiology laboratories. A surge in immigration and international travel has led to a rise in the number of imported cases of parasitosis, and this trend is expected to continue in the future. The present article addresses this challenge by reviewing recommended diagnostic approaches and tests. Currently, microscopy is always recommended when analysing blood samples for parasites. If malaria is suspected, rapid antigen testing (including at least HRP2 antigen) should also be performed. The work-up for suspected leishmaniasis should include serology, culture, and in selected cases detection of antigen in urine. In suspected Chagas disease, two different serological tests should be performed. PCR for blood protozoa is highly sensitive, although it cannot be used to rule out Chagas disease, since this condition may be present without parasitemia. Accurate diagnosis of intestinal amebiasis usually requires PCR or antigen detection tests. In helminthiasis, traditional microscopy may need to be complemented with other tests, such as agar plate culture for strongyloidiasis, Og4C3 antigen detection for bancroftian filariasis, and antibody detection test for filariasis and schistosomiasis.

Travelers' Diarrhea in Children at Risk: An Observational Study From a Spanish Database.

Background: Gastrointestinal symptoms are a common cause of consultation about children traveling to or coming from developing countries. The aim of this study was to identify the risk factors associated with gastrointestinal syndrome in children who travel. Methods: A prospective observational analytical and multicenter study was performed within +Redivi, a Spanish Tropical Medicine network on imported infections, from January 2009 to December 2013. All participants aged 16 years and younger were included in the analysis. Ethical approval was obtained from all the participating centers. Results: A total of 606 children ⩽16 years of age were registered in the +Redivi database during the study period. Median age was 8.7 years (interquartile range, 4.4–12.4 years), 65.8% (399/606) were immigrants, 90% were >2 years old and 54% were male. Median travel duration, excluding immigrants, was 50 days (interquartile range, 30–150 days). Children with gastrointestinal symptoms represented 13.5% (82/606) of total consultations. A significant association was found in bivariate analysis between gastrointestinal disorder and age <2 years (P < 0.01) and travel duration (P = 0.046). Immigrants had less gastrointestinal disorders than tourists (P < 0.05). The most prevalent infection was protozoan in 23.4% (142/606), and Giardia intestinalis was the most common pathogen in 10.1% (61/606) of total children. Independent risk factors for gastrointestinal symptoms were tourist and traveler child visiting friends and relatives (P = 0.03), travel duration <90 days (P = 0.008) and bacterial cause (P < 0.001). Conclusions: Traveling children who developed a gastrointestinal syndrome represented 13.5% of the total pediatric consultations in +Redivi. Independent risk factors were tourist or traveler visiting friends and relatives, travel duration <90 days and bacterial infection. G. intestinalis was the most common infectious agent causing a gastrointestinal disorder in the traveler children.

LAMP kit for diagnosis of non-falciparum malaria in Plasmodium ovale infected patients

BackgroundMicroscopy and rapid diagnosis tests have a limited sensitivity in diagnosis of malaria by Plasmodium ovale. The LAMP kit (LoopAMP®) can be used in the field without special equipment and could have an important role in malaria control programmes in endemic areas and for malaria diagnosis in returned travellers. The performance of the Pan primer of the kit in detecting malaria by P. ovale was compared with the results of standard nPCR in samples of patients returning from P. ovale endemic areas.MethodsPlasmodium ovale positive samples (29, tested by PCR and/or microscopy) and malaria negative specimens (398, tested by microscopy and PCR) were collected in different hospitals of Europe from June 2014 to March 2016 and frozen at −20xa0°C. Boil and spin method was used to extract DNA from all samples and amplification was performed with LoopAMP® MALARIA kit (Eiken Chemical, Japan) in an automated turbidimeter (Eiken 500). The results of LAMP read by turbidimetry and with the naked eye were compared.ResultsThe kit showed a sensitivity of 100% and a specificity of 97.24% with positive and negative predictive values of 72.5 and 100%, respectively. Naked eyed readings were in accordance with turbidimetry readings (sensitivity, 92.5%, specificity, 98.96% and positive and negative predictive values, respectively, 90.24 and 99.22%). The limit of detection of LAMP assay for P. ovale was between 0.8 and 2 parasites/µl.ConclusionsThe Pan primer of the Malaria kit LoopAMP® can detect P. ovale at very low-levels and showed a predictive negative value of 100%. This tool can be useful in malaria control and elimination programmes and in returned travellers from P. ovale endemic areas. Naked eye readings are equivalent to automated turbidimeter readings in specimens obtained with EDTA.

Aspergillus tamarii keratitis in a contact lens wearer

Keratitis produced by Aspergillus tamarii has been previously described associated to an ocular injury. We report a case in a contact lens wearer with a history of previous bilateral myopic LASIK ablation, bilateral intracorneal rings and vitrectomy and scleral buckling in his left eye. The fungus could be quickly identified combining phenotype, microscopy and mass spectrometry. Treatment with intravenous amphotericin, oral voriconazole, and topical amphotericin and natamycin and voriconazole was needed for corneal preservation.