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The Medici family was a powerful family from Florence, Italy, that gained prominence under Cosimo de' Medici in the early 15th century (1). Dynastic power granted Medici family members a [...]

Abstract Background In Jimma Zone, Ethiopia, the first-line treatment of uncomplicated falciparum malaria has been changed from sulphadoxine-pyrimethamine (SP) to artemether-lumefantrine (AL) in 2006. The objective of this study was to assess the effectiveness of AL in Jimma Zone two to three years after its broad introduction. Methods An open-label, single-arm, 42-day study of AL against falciparum malaria was conducted in four areas with moderate transmission in Jimma Zone between November 2008 and January 2009 and between August and December 2009. Patients (one-81 years) with uncomplicated Plasmodium falciparum mono-infection were consecutively enrolled. Follow-up visits were at day 2, 3, 7, 28 and 42 or any other day if symptoms reoccurred. Primary and secondary endpoints were PCR-corrected and uncorrected cure rates (molecular differentiation between recrudescence and re-infection) on days 28 and 42. Other secondary endpoints were gametocytaemia at day 7 and day 28, parasitaemia at day 2 and 3, and re-infection rates at day 28 and day 42. Results Of 348 enrolled patients, 313 and 301 completed follow-up at day 28 and at day 42, respectively. No early treatment failure occurred. For per protocol analysis, PCR-uncorrected cure rates at day 28 and 42 were 99.1% (95% CI 98.0-100.0) and 91.1% (95% CI 87.9-94.3), respectively. PCR-corrected cure rates at day 28 and 42 were 99.4% (95% CI 98.5-100.0) and 94.7% (95% CI 92.2-97.2), respectively. PCR-corrected cure rate at day 42 for children ≤5 years was 90.6% (95% CI 82.4-98.7) only. Adverse events were in general mild to moderate. Incidence of new infections was 3.4% during 42 days, no new infections with Plasmodium vivax were observed. Microscopically detected gametocytaemia was reduced by 80% between day 0 and day 7. Conclusion In general, AL was effective and well tolerated in Jimma Zone, Ethiopia. However, the PCR-corrected recrudescence rate per-protocol at day 42 for children ≤5 years was 9.4%. Therefore, further development should be monitored on a regular basis as recommended by WHO.

Abstract Background Real-time quantitative nucleic acid sequence-based amplification (QT-NASBA) is a sensitive method for detection of sub-microscopic gametocytaemia by measuring gametocyte-specific mRNA. Performing analysis on fresh whole blood samples is often not feasible in remote and resource-poor areas. Convenient methods for sample storage and transport are urgently needed. Methods Real-time QT-NASBA was performed on whole blood spiked with a dilution series of purified in-vitro cultivated gametocytes. The blood was either freshly processed or spotted on filter papers. Gametocyte detection sensitivity for QT-NASBA was determined and controlled by microscopy. Dried blood spot (DBS) samples were subjected to five different storage conditions and the loss of sensitivity over time was investigated. A formula to approximate the loss of Pfs25-mRNA due to different storage conditions and time was developed. Results Pfs25-mRNA was measured in time to positivity (TTP) and correlated well with the microscopic counts and the theoretical concentrations of the dilution series. TTP results constantly indicated higher amounts of RNA in filter paper samples extracted after 24 hours than in immediately extracted fresh blood. Among investigated storage conditions freezing at −20°C performed best with 98.7% of the Pfs25-mRNA still detectable at day 28 compared to fresh blood samples. After 92 days, the RNA detection rate was only slightly decreased to 92.9%. Samples stored at 37°C showed most decay with only 64.5% of Pfs25-mRNA detectable after one month. The calculated theoretical detection limit for 24 h-old DBS filter paper samples was 0.0095 (95% CI: 0.0025 to 0.0380) per μl. Conclusions The results suggest that the application of DBS filter papers for quantification of Plasmodium falciparum gametocytes with real-time QT-NASBA is practical and recommendable. This method proved sensitive enough for detection of sub-microscopic densities even after prolonged storage. Decay rates can be predicted for different storage conditions as well as durations.

Abstract Background The emergence of drug resistance is a major problem in malaria control. Combination of molecular genotyping and characterization of mutations or single nucleotide polymorphisms (SNPs) correlated with drug resistance can provide information for subsequent surveillance of existing and developing drug resistance patterns. The introduction of artemether/lumefantrine (AL) as first-line treatment, never used before in Ethiopia, allowed the collection of baseline data of molecular polymorphisms before a selection due to AL could occur. Method 97 patients with uncomplicated falciparum malaria were recruited from April to June 2006 and treated with either AL, quinine (Q) or atovaquone/proguanil (AP) in Jimma University Hospital, Ethiopia. Mutations or SNPs associated with resistance to these drugs were analysed by RFLP (pfdhfr, pfmdr1) and sequencing of the target genes (pfcytb, pfserca ). Results SNPs previously reported to be associated with resistance to the study drugs were identified in recrudescent and treatment sensitive isolates. A total of seven recrudescences were obtained. The pfmdr1 N86Y mutation was found in 84.5% of isolates. The triple mutation 51I,59R,108N of the pfdhfr gene occured in high frequency (83.3%) but no pfcytb mutation was detected. Sequencing showed a variety of previously described and new mutations in the pfserca gene. Conclusion The prevalence of mutations was in accordance with the expected patterns considering recent drug regimens. The broad introduction of AL and the cessation of former drug regimens might probably change the current distribution of polymorphisms, possibly leading to decreased sensitivity to AL in future. Continuous surveillance of molecular patterns in this region is, therefore, recommended.

Abstract Background Between 10,000 and 12,000 cases of imported malaria are notified in the European Union each year. Despite an excellent health care system, fatalities do occur. In case of advanced autolysis, the post-mortem diagnostic is impaired. Quicker diagnosis could be achieved by using rapid diagnostic malaria tests. Methods In order to evaluate different methods for the post-mortem diagnosis of Plasmodium falciparum malaria in non-immunes, a study was performed on the basis of forensic autopsies of corpses examined at variable intervals after death in five cases of fatal malaria (with an interval of four hours to five days), and in 20 cases of deaths unrelated to malaria. Detection of parasite DNA by PCR and an immunochromatographic test (ICT) based upon the detection of P. falciparum histidine-rich protein 2 (PfHRP2) were compared with the results of microscopic examination of smears from cadaveric blood, histopathological findings, and autopsy results. Results In all cases of fatal malaria, post-mortem findings were unsuspicious for the final diagnosis, and autoptic investigations, including histopathology, were only performed because of additional information by police officers and neighbours. Macroscopic findings during autopsy were unspecific. Histopathology confirmed sequestration of erythrocytes and pigment in macrophages in most organs in four patients (not evaluable in one patient due to autolysis). Microscopy of cadaveric blood smears revealed remnants of intraerythrocytic parasites, and was compromised or impossible due to autolysis in two cases. PCR and ICT performed with cadaveric blood were positive in all malaria patients and negative in all controls. Conclusion In non-immune fatalities with unclear anamnesis, ICT can be recommended as a sensitive and specific tool for post-mortem malaria diagnosis, which is easier and faster than microscopy, and also applicable when microscopic examination is impossible due to autolysis. PCR is more expensive and time-consuming, but may be used as confirmatory test. In highly endemic areas where asymptomatic parasitaemia is common, confirmation of the diagnosis of malaria as the cause of death has to rely on histopathological findings.

Abstract Background Due to increasing drug resistance, artemisinin-based combination chemotherapy (ACT) has become the first-line treatment of falciparum malaria in many endemic countries. However, irreversible ototoxicity associated with artemether/lumefantrine (AL) has been reported recently and suggested to be a serious limitation in the use of ACT. The aim of the study was to compare ototoxicity, tolerability, and efficacy of ACT with that of quinine and atovaquone/proguanil in the treatment of uncomplicated falciparum malaria. Methods Ninety-seven patients in south-west Ethiopia with slide-confirmed malaria were randomly assigned to receive either artemether/lumefantrine or quinine or atovaquone/proguanil and followed-up for 90 days. Comprehensive audiovestibular testing by pure tone audiometry (PTA), transitory evoked (TE) and distortion product (DP) otoacoustic emissions (OAE) and brain stem evoked response audiometry (BERA) was done before enrolment and after seven, 28 and 90 days. Results PTA and DP-OAE levels revealed transient significant cochlear hearing loss in patients treated with quinine but not in those treated with artemether/lumefantrine or atovaquone/proguanil. TE-OAE could be elicited in all examinations, except for three patients in the Q group on day 7, who suffered a transient hearing loss greater than 30 dB. There was no evidence of drug-induced brain stem lesions by BERA measurements. Conclusion There was no detrimental effect of a standard oral regimen of artemether/lumefantrine on peripheral hearing or brainstem auditory pathways in patients with uncomplicated falciparum malaria. In contrast, transient hearing loss is common after quinine therapy and due to temporary outer hair cell dysfunction.

Abstract Background In Tanzania, drug-resistant malaria parasites are an increasing public health concern. Because of widespread chloroquine (CQ) resistance Tanzania changed its first line treatment recommendations for uncomplicated malaria from CQ to sulfadoxine-pyrimethamine (SP) in 2001. Loss of SP sensitivity is progressing rapidly. SP resistance is associated with mutations in the dihydrofolate reductase (pfdhfr) and dihydropteroate synthase (pfdhps) genes. Methods In samples from 86 patients with uncomplicated Plasmodium falciparum malaria from Mbeya and Matema, Mbeya region, south-western Tanzania, the occurrence of mutations was investigated in the pfcrt and pfmdr1 genes which are associated with CQ resistance and in pfdhfr and pfdhps, conferring SP resistance, as well in cytb which is linked to resistance to atovaquone. Results Pfcrt T76 occurs in 50% and pfmdr1 Y86 in 51.7%. Pfdhfr triple mutations coexisting with pfdhps double mutations were detected in 64.3% of the P. falciparum isolates. This quintuple mutation is seen as a possible predictive molecular marker for SP treatment failure. Mutations of the cytb gene were not detected. Conclusion These findings of a high prevalence of mutations conferring SP resistance correspond to data of in vivo SP efficacy studies in other regions of Tanzania and underline the recommendation of changing first-line treatment to artemisinin-based combination therapy.

Background The purpose of this exploratory study was to evaluate different accelerated tick-borne encephalitis (TBE) vaccine schedules for last-minute travellers. Methods In a single-centre, open-label pilot study, 77 TBE-naïve Belgian soldiers were randomized to one of the following five schedules with FSME-Immun®: group 1 ('classical accelerated' schedule) received one intramuscular (IM) dose at Day 0 and Day 14, group 2 two IM doses at Day 0, group 3 two intradermal (ID) doses at Day 0, group 4 two ID doses at Day 0 and Day 7 and group 5 two ID doses at Day 0 and Day 14. The last dose(s) of the primary vaccination scheme were given after 1 year: IM (1 dose) or ID (2 doses). TBE virus neutralizing antibodies were measured in a plaque reduction neutralization test (PRNT90 and 50) at Days 0, 14, 21, 28, Months 3, 6, 12 and 12+21 days. Seropositivity was defined as neutralizing antibody titres ≥10. Results The median age was 19–19.5 years in each group. Median time to seropositivity up to Day 28 was shortest for PRNT90 in ID-group 4 and for PRNT50 in all ID groups. Seroconversion until Day 28 peaked highest for PRNT90 in ID-group 4 (79%) and for PRNT50 in ID-groups 4 and 5 (both 100%). Seropositivity after the last vaccination after 12 months was high in all groups. Previous yellow fever vaccination was reported in 16% and associated with lower geometric mean titres of TBE-specific antibodies at all-time points. The vaccine was generally well tolerated. However, mild to moderate local reactions occurred in 73–100% of ID compared with 0–38% of IM vaccinations, and persistent discolouration was observed in nine ID vaccinated individuals. Conclusion The accelerated two-visit ID schedules might offer a better immunological alternative to the recommended classical accelerated IM schedule, but an aluminium-free vaccine would be preferable. [ABSTRACT FROM AUTHOR]

Objective: The available epidemiological and clinical evidence from the currently ongoing monkeypox (MPX) outbreak in non-endemic areas suggests an important factor of sexual transmission. However, limited information on the behaviour and experiences of individuals with an MPX infection has to date been provided. We aimed to describe the initial phase of the MPX outbreak in Belgium, and to provide a more in-depth description of sexual behaviour and transmission contexts.Methods: We used routine national surveillance data of 139 confirmed MPX cases with date of symptom onset until 19 June 2022, complemented with 12 semistructured interviews conducted with a subsample of these cases.Results: Sexualised environments, including large festivals and cruising venues for gay men, were the suspected exposure setting for the majority of the cases in the early outbreak phase. In-depth narratives of sexual behaviour support the hypothesis of MPX transmission through close physical contact during sex. Despite awareness of the ongoing MPX outbreak, low self-perceived risk of MPX acquisition and confusing initial signs and symptoms for other STIs or skin conditions delayed early detection of an MPX infection. In addition, we describe relevant contextual factors beyond individual behaviour, related to sexual networks, interpersonal interactions and health systems. Some of these factors may complicate early MPX detection and control efforts.Conclusion: Our results highlight the role of sexual contact and networks in the transmission of MPX during the early phase of the outbreak in Belgium. Risk communication messages should consistently and transparently state the predominant sexual transmission potential of MPX virus, and prevention and control measures must be adapted to reflect multilevel factors contributing to MPX transmission risk. [ABSTRACT FROM AUTHOR]

To the Editor: Studies conducted in Malaysia have raised questions about Plasmodium knowlesi as the fifth human pathogenic malaria parasite (1,2); additional cases of P. knowlesi malaria have subsequently been [...]