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Current SARS-CoV-2 vaccines are losing efficacy against emerging variants and may not protect against future novel coronavirus outbreaks, emphasizing the need for more broadly protective vaccines. To inform the development of a pan-coronavirus vaccine, we investigated the presence and specificity of cross-reactive antibodies against the spike (S) proteins of human coronaviruses (hCoV) after SARS-CoV-2 infection and vaccination. We found an 11 to 123-fold increase in antibodies binding to SARS-CoV and MERS-CoV as well as a 2 to 4-fold difference in antibodies binding to seasonal hCoVs in COVID-19 convalescent sera compared to pre-pandemic healthy donors, with the S2 subdomain of the S protein being the main target for cross-reactivity. In addition, we detected cross-reactive antibodies to all hCoV S proteins after SARS-CoV-2 S protein immunization in macaques, with higher responses for hCoV more closely related to SARS-CoV-2. These findings support the feasibility of and provide guidance for development of a pan-coronavirus vaccine.

We report dengue virus (DENV) infection in two Dutch tourists who visited Département Var, southern France, in July and August 2020. As some autochthonous dengue cases have occurred in Europe in recent years, awareness among physicians and public health experts about possible intermittent presence of DENV in southern Europe is important to minimise delay in diagnosis and treatment. Quick diagnosis can lead to timely action to contain the spread of vector-borne diseases and minimise transmission.

Since the outbreak of COVID-19, chloroquine has been mentioned as a possible treatment. In vitro studies have shown anti-viral activity of chloroquine against SARS-CoV-2. Recently, the Dutch National Institute for Public Health and the Environment published treatment options for antiviral treatment for COVID-19 where chloroquine was suggested as first choice for off-label treatment, beside remdesivir en lopinavir/ritonavir. In this commentary, we provide a background and history of chloroquine, the evidence for antiviral efficacy of chloroquine and the arguments for off-label use of chloroquine in COVID-19.

In de rubriek Frictie geven wisselende auteurs hun visie op een onderwerp dat discussie oproept, of kijken zij kritisch naar een misverstand of dilemma waar professionals in hun werk tegenaan lopen

Parasite clearance data from 18,699 patients with falciparum malaria treated with an artemisinin derivative in areas of low (n=14,539), moderate (n=2077), and high (n=2083) levels of malaria transmission across the world were analyzed to determine the factors that affect clearance rates and identify a simple in vivo screening measure for artemisinin resistance. The main factor affecting parasite clearance time was parasite density on admission. Clearance rates were faster in high-transmission settings and with more effective partner drugs in artemisinin-based combination treatments (ACTs). The result of the malaria blood smear on day 3 (72 h) was a good predictor of subsequent treatment failure and provides a simple screening measure for artemisinin resistance. Artemisinin resistance is highly unlikely if the proportion of patients with parasite densities of

Little is known about the rate at which genetic variation is generated within intrahost populations of dengue virus (DENV) and what implications this diversity has for dengue pathogenesis, disease severity, and host immunity. Previous studies of intrahost DENV variation have used a low frequency of sampling and/or experimental methods that do not fully account for errors generated through amplification and sequencing of viral RNAs. We investigated the extent and pattern of genetic diversity in sequence data in domain III (DIII) of the envelope (E) gene in serial plasma samples ( n = 49) taken from 17 patients infected with DENV type 1 (DENV-1), totaling some 8,458 clones. Statistically rigorous approaches were employed to account for artifactual variants resulting from amplification and sequencing, which we suggest have played a major role in previous studies of intrahost genetic variation. Accordingly, nucleotide sequence diversities of viral populations were very low, with conservative estimates of the average levels of genetic diversity ranging from 0 to 0.0013. Despite such sequence conservation, we observed clear evidence for mixed infection, with the presence of multiple phylogenetically distinct lineages present within the same host, while the presence of stop codon mutations in some samples suggests the action of complementation. In contrast to some previous studies we observed no relationship between the extent and pattern of DENV-1 genetic diversity and disease severity, immune status, or level of viremia.

Objectives: To explore clinical and virological characteristics and describe the epidemiology of dengue in patients who presented with acute undifferentiated fever (AUF) at primary health centers (PHC) in Binh Thuan Province, Vietnam. Methods: A prospective observational study was conducted from 2001 to 2006 to study the aetiology in AUF patients. Demographic and clinical information was obtained, and dengue polymerase chain reaction (RT-PCR) and serology were performed on a random selection of patients. Results: Three hundred fifty-one serologically confirmed dengue patients including 68 primary and 283 secondary infections were included in this study. In 25% (86/351) dengue virus (DENV) was detected by RT-PCR among which 32 DENV-1, 16 DENV-2, 1 DENV-3 and 37 DENV-4 were identified. The predominant dengue serotype varied by year with seasonal fluctuation: DENV-4 in 2001-2002, DENV-1 and DENV-2 from 2003 to 2006. Primary dengue was more common in children. Higher viraemia levels (P = 0.010) were found in primary infections compared to secondary infections. DENV-1 infected patients had higher viraemia levels than DENV-2 (P = 0.003) and DENV-4 (P

Only anecdotal data are available on the pharmacokinetics (PK) of miltefosine in children suffering from visceral leishmaniasis (VL). While failure rates were higher in children with VL, steady-state concentrations appeared lower than those seen with adults. We hypothesized that the current linear dosage (in milligrams per kilogram of body weight) is too low for children and that a new dosing algorithm based on an appropriate body size model would result in an optimal exposure. A population PK analysis was performed on three historic pooled data sets, including Indian children, Indian adults, and European adults. Linear and allometric scaling of PK parameters by either body weight or fat-free mass (FFM) was evaluated for body size models. Based on the developed PK model, a dosing algorithm for miltefosine in children and adults was proposed and evaluated in silico . The population PK model employing allometric scaling fitted best to the pooled miltefosine data. Allometric scaling by FFM reduced between-subject variability, e.g., for drug clearance, from 49.6% to 32.1%. A new allometric miltefosine dosing algorithm was proposed. Exposure to miltefosine was lower in children than adults receiving 2.5 mg/kg/day: a C max of 18.8 μg/ml was reached by 90% of adults and 66.7% of children. The allometric daily dose resulted in similar levels of exposure to miltefosine for adults and children. The use of a new allometric dosing algorithm for miltefosine in VL patients results in optimal exposure to miltefosine in both adults and children and might improve clinical outcome in children.

To describe patient characteristics and disease spectrum among foreign visitors to Haiti before and after the 2010 earthquake, we used GeoSentinel Global Surveillance Network data and compared 1 year post-earthquake versus 3 years pre-earthquake. Post-earthquake travelers were younger, predominantly from the United States, more frequently international assistance workers, and more often medically counseled before their trip than pre-earthquake travelers. Work-related stress and upper respiratory tract infections were more frequent post-earthquake; acute diarrhea, dengue, and Plasmodium falciparum malaria were important contributors of morbidity both pre- and post-earthquake. These data highlight the importance of providing destination- and disaster-specific pre-travel counseling and post-travel evaluation and medical management to persons traveling to or returning from a disaster location, and evaluations should include attention to the psychological wellbeing of these travelers. For travel to Haiti, focus should be on mosquito-borne illnesses (dengue and P. falciparum malaria) and travelers' diarrhea.

Diagnostic dengue in febrile patients is challenging. Of a total of 459 patients with acute undifferentiated fever, randomly selected from 12 primary health facilities and 1 clinic of the provincial malaria station in southern Vietnam, dengue-specific antibody (Ab) and NS1 Ag enzyme-linked immunosorbent assay (ELISA) (Platelia (TM) Bio-Rad Laboratories, Hercules, Ca 94547. US) were performed on acute (t3) and convalescent (t3 weeks) sera. Polymerase chain reaction (PCR) was used for confirmation. Based on a composite of the NS1 Ag-ELISA, Ab-ELISA, and PCR results. 54 (12%) patients had acute dengue. Positive and negative predictive values were 65% and 98% for the Ab-based diagnosis and 91% and 92% for NS1Ag, respectively. The agreement between Ab- and NS1Ag-based diagnosis was poor (k value, 0.2). Two patients without dengue had detectable NS1Ag on t0 and t3.1 just above the cutoff value and 1 with very high values. For 5 dengue patients, NS1Ag was still detectable at very high levels at t3. Dengue NS1Ag can be used for early diagnosis of dengue; infrequent false-positive results need further clarification. (C) 2009 Elsevier Inc. All rights reserved

A sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for the quantification of miltefosine is presented. A 250 mu L human EDTA plasma aliquot was spiked with miltefosine and extracted by a solid-phase extraction method. Separation was performed on a Gemini C 18 column (150 mm x 2.0 mm I.D., 5 mu m) using an alkaline eluent. Detection was performed by positive ion electrospray ionization followed by triple-quadrupole mass spectrometry. The assay has been validated for miltefosine from 4 to 2000 ng/mL using 250 mu L human EDTA plasma samples. Results from the validation demonstrate that miltefosine can be accurately and precisely quantified in human plasma. At the lowest level, the intra-assay precision was lower than 10.7%, the inter-assay precision was 10.6% and accuracies were between 95.1 and 109%. This assay is successfully used in a clinical pharmacokinetic study with miltefosine. (c) 2008 Elsevier B.V. All rights reserved

A follow-up study was conducted with 23 months interval to investigate the seroepidemiology and persistence of Leptospira IgG antibodies among healthy children in Binh Thuan province, Southern Vietnam. Sera from 262 children (7-13 years of age) were collected and analysed with a commercially available enzyme-linked immunosorbent assay (ELISA) for Leptospira IgG. Seroconversion was observed in 10.4% (22 of 211, 95% CI: 5.6-26.7) of the children, of whom 18 (8.5%) had probably and four (1.9%) had certainly been exposed to Leptospira. Based on the reduction of sero-negatives of 1.9% among children who have been certainly exposed, the annual seroconversion rate, a measure of the incidence rate of Leptospira infections, corresponds to 0.99% (95% CI: 0.39-2.52). In 61% (31 of 51, 95% CI: 47.1-73.0) of the children with past-infection, Leptospira IgG antibodies remain detectable after 2 years. Data from this study indicate that IgG antibody responses against Leptospira may persist at least for 2 years in children without manifestations of leptospirosis. Results of study uncover the true incidence of leptospirosis infection, the dynamics of waxing and waning antibody concentrations and points at a larger burden of clinically non-significant Leptospira infections in Southern Vietnam. This also indicates background reactivity for serological testing and thus serological result of a single serum sample must be carefully interpreted.

OBJECTIVE To study the incidence of asymptomatic primary dengue infections among children and reactivity against other flaviviruses. METHODS A total of 216 children, who had no dengue-specific IgG antibodies during a serosurvey in 2003 were re-examined 23 months later to determine if seroconversion had occurred. Dengue-specific IgG was demonstrated with enzyme-linked immunosorbent assay (ELISA) and reactivity patterns against other flaviviruses were assessed by using immunofluorescence assay (IFA). RESULTS Sixty-six children had seroconverted for dengue virus-specific IgG; the true annual incidence of primary dengue was thus 17.3% (95% CI: 13.8-21.4). Japanese Encephalitis virus (JEV)-specific IgG antibodies were detected by IFA among three (4.6%) samples that showed seroconversion in the dengue ELISA, because of cross-reactivity. CONCLUSION Our findings highlight the high incidence of dengue among Vietnamese children; JEV infections are rare. The true annual incidence of dengue can be estimated with a single cross-sectional seroprevalence survey.

Summary Objective To determine the presence of brucellosis among patients with acute febrile illness at health care facilities in Binh Thuan province, Vietnam. Method A retrospective seroepidemiological study on serum samples collected at 13 not adjacent health care facilities using the Rose Bengal test as a rapid screening test and the Brucella IgM/IgG flow assay as a simple confirmatory test. Result The seroprevalence in the Rose Bengal test among 406 patients presented with acute undifferentiated fever was 14.8%. Seven of the 64 Rose Bengal test positive samples reacted weakly (1+) positive in the Brucella IgM/IgG flow assay. No seroconversion was observed. Conclusions Brucellosis is not a major cause of morbidity in Binh Thuan province.

Summary Objectives To describe the characteristics of patients consulting commune primary healthcare posts for acute undifferentiated fever not being malaria (AUF), and to explore the diagnostic and therapeutic responses of the healthcare workers. Methods All patients presenting with AUF at 12 commune health posts and one clinic at the provincial malaria station, Binh Thuan, a dengue endemic province in southern Vietnam, were included. Record forms were used to fill in patient and diseases characteristics, pre-referral treatment, signs and symptoms, provisional diagnosis and installed treatment, referral and final outcome. Results Two thousand ninety-six patients were included from April 2001 to March 2002. The median delay to attend the health posts was, 0.87 day for >5, 1.15 days for children aged 5–15 years and 1.41 days for adults (P

Early diagnosis and treatment of malaria (EDTM) is a key component of malaria control. The success of EDTM depends on health seeking behaviour and the quality of the health service. This study assessed self-diagnosis, treatment and treatment delay after the introduction of EDTM in 1993. In southern Vietnam EDTM comprises microscopic diagnosis and free treatment with artemisinin derivatives at public health facilities. Until 2001, 1698 questionnaires had been completed by patients participating in randomized treatment trials of uncomplicated malaria. The presumptive self diagnosis 'malaria' increased from 68% in 1993 to 100% in 2001 and self-treatment decreased, from 74% to 8% in 2000 and 24% in 2001. The median (maximum) delay between first symptoms and seeking treatment at a public health facility decreased from 3 (23) to 1.3 (3) days (P

OBJECTIVES To study a new combination, based on dihydroartemisinin and piperaquine (CV8) and atovaquone/proguanil (Malarone) for treatment of uncomplicated falciparum malaria in Vietnam. METHODS Vietnamese adults with falciparum malaria were allocated randomly to treatment with dihydroartemisinin/piperaquine/trimethoprim/primaquine 256/2560/720/40 mg (CV8, n = 84) or Malarone 3000/1200 mg (n = 81), both over 3 days. Patients were followed-up for 28 days. RESULTS All patients recovered rapidly. The mean (95% CI) parasite elimination half-life of CV8 was 6.8 h (6.2-7.4) and of Malarone 6.5 h (6.1-6.9) (P = 0.4). Complete parasite clearance time was 35 (31-39) and 34 h (31-38) (P = 0.9). The 28-day cure rate was 94% and 95%, respectively (odds ratio 0.84, 95% CI 0.18-3.81). No significant side-effects were found. CONCLUSION CV8 and Malarone are effective combinations against multi-drug resistant falciparum malaria. CV8 has the advantage of a low price.

Summary Chloroquine-resistant Plasmodium vivax has not yet occurred in Vietnam. The efficacy of artemisinin forP.vivaxwasnotestablished.Weconductedadouble-blindrandomizedstudyinvolving240inpatientswithP. vivax malaria who received artemisinin (40 mg/kg over 3 days) plus placebo chloroquine (Art) orchloroquine(25 mg/kgover3 days)plusplaceboartemisinin(Chl).Patientswerefollowedupwithweeklyblood smears for 28 days. In each group 113 cases were analysed. All patients recovered rapidly. Themedian (range) parasite clearance time of regimen Art was 24 h (8–72) and of Chl 24 h (8–64; P ¼ 0.3).Parasitesreappearedintwocasesineachgrouponday14,ineightcasesineachgroup(7%)onday16andin 25 (23%) and 18 (16%) cases, respectively, at the end of 4-week follow-up (P ¼ 0.3). The populationparasite clearance curve followed a mono-exponential decline. The parasite reduction ratio per 48 hreproduction cycle was 2.3 · 10 4 for both regimens. We conclude that artemisinin and chloroquine areequallyeffectiveinthetreatmentofP.vivaxinfectionsinVietnam.Reappearanceofparasitesbeforeday16(7%) suggests the emergence of chloroquine resistance. Three days of artemisinin monotherapy does notprevent recrudescence.keywords Plasmodium vivax, artemisinin, chloroquine, Vietnam, drug-resistance, recrudescencecorrespondence P. J. de Vries, Division of Infectious Diseases, Tropical Medicine and AIDS, AcademicMedical Center, F4-217, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.Tel: (+)31 (0)20 5664380; Fax: (+)31 (0)20 6972286; E-mail: p.j.devries@amc.uva.nlIntroductionIn South-east Asia morbidity attributable to Plasmodiumvivax prevails while P. falciparum gradually comes undercontrol by applying artemisinin drugs with other controlmeasures such as insecticide-treated bed nets (Phan et al.1999; Nosten et al. 2000). This trend was also observed inBinh Thuan, a mountainous province in the south ofVietnam (unpublished information, Binh Thuan ProvincialMalaria Station).Chloroquineisthefirst-linedrugfortreatmentofP.vivaxin most areas of the world (World Health Organization1997), although artemisinin and derivatives are also used invarious regimens and they appear to be effective (Nguyenet al. 1993). It was not yet known whether chloroquine-resistantP.vivaxisprevalentinVietnam.Artemisinindrugsare very active against P. vivax but the efficacy has not beenfirmly established. Therefore, this study aimed to establishand compare the efficacy of artemisinin and chloroquine inthe treatment of blood stage infections of P. vivax inVietnam. Based on our own experience in pharmacody-namicmodellingofthetimecourseofP.falciparum,a3-dayregimen of artemisinin should be effective. Longer regimenswere considered to conflict with good patient compliance.MethodsPatient selection and treatmentFrom September 1997 to January 2000, subjects aged15 years or older with a microscopically confirmed P. vivax(asexual stage) infection, presenting at eight primary health

Combinations of artemisinin and quinine for uncomplicated falciparum malaria were studied. A total of 268 patients were randomized to 7 days of quinine at 10 mg/kg of body weight three times a day (Q) or to artemisinin at 20 mg/kg of body weight followed by 3 (AQ3) or 5 (AQ5) days of quinine. Recrudescence rates were 16, 38, and 15% for the Q, AQ3, and AQ5 groups, respectively ( P < 0.001). Recrudescence was associated with shorter parasite clearance time (PCT) and longer treatment after the blood smear had become negative (eradication time). However, classification of patients to outcome—recrudescence or radical cure—was correct in only 77% of patients. The population kinetics of the parasitemia was estimated with nonlinear mixed-effect models. Several models were tested, but the best model was a monoexponential decline of the parasitemia in which the mean parasite elimination half-life was shorter after artemisinin (5.1 h; 95% confidence interval [CI], 4.9 to 5.2 h) than after quinine (8.0 h [95% CI, 7.5 to 8.3 h]). Attempts to simulate the initial increase of the parasitemia did not result in better models with a biologically plausible interpretation. Recrudescence was associated with slower parasite clearance and a higher simulated terminal parasitemia ( P term ). The classification of patients to outcome groups based on P term was correct in 78% of patients. The data suggest that parasite strains with reduced sensitivity to quinine are prevalent in Vietnam, with slower parasite clearance and consequent recrudescence. A single dose of artemisinin induces rapid parasite reduction and lowers the value of P term , but to prevent recrudescence, this should be followed by quinine for at least 3 days after parasite clearance, or 5 days in total.

The first choice for treatment of Clonorchis sinensis infections is praziquantel. Experimental data suggest that artemisinin derivatives are active against C. sinensis. The efficacy of both drugs against clonorchiasis was evaluated in a pilot study in clonorchiasis patients in an endemic area in the North of Vietnam. Twenty-one patients received praziquantel 25 mg/kg o.d. for three days, the regular regimen in that area, and 21 patients were treated with artemisinin 500 mg b.i.d. for 5 days. Faecal egg counts were performed before as well as 6 days and 5 weeks after treatment. In the praziquantel group the faecal egg count decreased significantly from a mean value of 1632 eggs per gram faeces (epg) to 37 epg 5 weeks after treatment (P < 0.01) but, surprisingly, the eradication rate (95% confidence limit) at week 5 was only 29% (11-52%). In the artemisinin-treated group the reduction of the egg count was insignificant: from 1103 to 542 epg (P > 0.05). The proportion of patients (95% c.l.) with C. sinensis eggs in their stool on week 5 was 90% (70-99%) in the artemisinin group and 71% (48-89%) in the praziquantel group (P > 0.05) and the eradication rate (95% c.l.) at week 5 was only 10% (1-30%). With a sensitivity of detection of eggs in stool > 0.89, this implies a statistically significant but clinically unsatisfactory reduction for treatment with praziquantel. Sensitivity is probably less. For artemisinin there was no significant reduction. In conclusion, for human clonorchiasis in the North of Vietnam, the efficacy of praziquantel 25 mg/kg o.d. for 3 days was unsatisfactory and artemisinin for 5 days is not an effective alternative

Study objectives: To establish the value of electrical impedance tomography (EIT) in assessing pulmonary edema in noncardiogenic acute respiratory failure (ARF), as compared to the thermal dye double indicator dilution technique (TDD). Design: Prospective clinical study. Setting: ICU of a general hospital. Patients: Fourteen ARF patients. Interventions: In order to use the TDD to determine the amount of extravascular lung water (EVLW), a fiberoptic catheter was placed in the femoral artery. Measurements and main results: Fourteen consecutive ARF patients receiving mechanical ventilation were measured by EIT and TDD. EIT visualizes the impedance changes caused by the ventilation in two-dimensional image planes. An impedance ratio (IR) of the ventilation-induced impedance changes of a posterior and an anterior part of the lungs was used to indicate the amount of EVLW. For the 29 measurements in 14 patients, a significant correlation between EIT and TDD (r = 0.85; p< 0.001) was found. The EIT reproducibility was good. The diagnostic value of the method was tested by receiver operator characteristic analysis, with 10 mL/kg of EVLW considered as the upper limit of normal. At a cutoff level of the IR of 0.64, the IR had a sensitivity of 93%, a specificity of 87%, and a positive predictive value of 87% for a supranormal amount of EVLW. Follow-up measurements were performed in 11 patients. A significant correlation was found between the changes in EVLW measured with EIT and TDD (r = 0.85; p < 0.005). Conclusion: We conclude that EIT is a noninvasive technique for reasonably estimating the amount of EVLW in noncardiogenic ARF.

The efficacy of the combination of a single oral dose of 500 mg artemisinin with a single 500 mg oral dose of mefloquine (AM) in the treatment of uncomplicated falciparum malaria was compared to mefloquine therapy alone (M) in a double-'blind' randomized study in an endemic area in the south of Viet Nam where single low dose treatment was employed and where mefloquine had been recently introduced. 231 patients, 117 AM and 114 M, were studied. Failure of therapy occurred in 1 AM patient and in 3 M patients. The radical cure rate was 84% for the AM regimen and 65% for the M regimen (P = 0.002). Recrudescence (including an unknown percentage of reinfections) occurred in 15% of AM patients and in 30% of M patients (P = 0.01). The mean parasite clearance time was 40 h (SD = 16) for AM and 60 h (SD = 27) for the M regimen (P = 0.0001). No effect of artemisinin was noted on gametocytes present on admission, but new gametocytes developed less frequently in the AM group. The addition of a single dose of 500 mg artemisinin to 500 mg mefloquine increased the efficacy and reduced the rate of recrudescence, but this regimen was not adequate and, for short course regimens, more doses of artemisinin as well as higher, doses of mefloquine should be studied.

Background Rwanda reported significant reductions in malaria burden following scale up of control intervention from 2005 to 2010. This study sought to; measure malaria prevalence, describe spatial malaria clustering and investigate for malaria risk factors among health-centre-presumed malaria cases and their household members in Eastern Rwanda. Methods A two-stage health centre and household-based survey was conducted in Ruhuha sector, Eastern Rwanda from April to October 2011. At the health centre, data, including malaria diagnosis and individual level malaria risk factors, was collected. At households of these Index cases, a follow-up survey, including malaria screening for all household members and collecting household level malaria risk factor data, was conducted. Results Malaria prevalence among health centre attendees was 22.8%. At the household level, 90 households (out of 520) had at least one malaria-infected member and the overall malaria prevalence for the 2634 household members screened was 5.1%. Among health centre attendees, the age group 5–15 years was significantly associated with an increased malaria risk and a reported ownership of ≥4 bednets was significantly associated with a reduced malaria risk. At the household level, age groups 5–15 and >15 years and being associated with a malaria positive index case were associated with an increased malaria risk, while an observed ownership of ≥4 bednets was associated with a malaria risk-protective effect. Significant spatial malaria clustering among household cases with clusters located close to water- based agro-ecosystems was observed. Conclusions Malaria prevalence was significantly higher among health centre attendees and their household members in an area with significant household spatial malaria clustering. Circle surveillance involving passive case finding at health centres and proactive case detection in households can be a powerful tool for identifying household level malaria burden, risk factors and clustering.

Background Exchange transfusion (ET) has remained a controversial adjunct therapy for the treatment of severe malaria. In order to assess the relative contribution of ET to parasite clearance in severe malaria, all patients receiving ET as an adjunct treatment to parenteral quinine or to artesunate were compared with patients treated with parenteral treatment with quinine or artesunate but who did not receive ET. ET was executed using a standardized manual isovolumetric exchange protocol. Methods All patients in the Rotterdam Malaria Cohort treated for severe P. falciparum malaria at the Institute for Tropical Diseases of the Harbour Hospital between 1999 and 2011 were included in this retrospective follow-up study. Both a two-stage approach and a log-linear mixed model approach were used to estimate parasite clearance times (PCTs) in patients with imported malaria. Severe malaria was defined according to WHO criteria. Results A total of 87 patients with severe malaria was included; 61 received intravenous quinine, whereas 26 patients received intravenous artesunate. Thirty-nine patients received ET as an adjunct treatment to either quinine (n = 23) or artesunate (n = 16). Data from 84 of 87 patients were suitable for estimation of parasite clearance rates. PCTs were significantly shorter after administration of artesunate as compared with quinine. In both models, ET did not contribute significantly to overall parasite clearance. Conclusion Manual exchange transfusion does not significantly contribute to parasite clearance in artesunate-treated individuals. There may be a small effect of ET on parasite clearance under quinine treatment. Institution of ET to promote parasite clearance in settings where artesunate is available is not recommended, at least not with manually executed exchange procedures.

Objective. The objective of our study was to evaluate impedance cardiography (IMP) as a noninvasive method to determine the left ventricular ejection fraction (LVEF).Methods. A total of 24 patients, 8 men and 16 women, aged 45.0 ± 12.9 years, participated in the study. They used cardiotoxic chemotherapeutic drugs or suffered from cardiac failure. LVEF was measured by means of IMP (LVEFimp) and radionuclide ventriculography (LVEFnuc). LVEFimp was calculated in three ways. Capan and colleagues [13] proposed a formula in which LVEF (LVEFCap) can be calculated from the systolic time intervals, namely, left ventricular ejection time and preejection time. Judy and colleagues [14] described a systolic (S) and a diastolic (D) part in the first derivative curve of the impedance signal. The ratio S/D might equal the LVEF (LVEFJud). A new LVEF calculation was introduced (LVEFimp) in this study based on the first derivative of the impedance signal, the thoracic impedance, and heart rate.Results. Mean LVEFCap was 59.9 ± 8.4%, which did not differ from LVEFnuc (59.9 ± 7.1%). However the correlation between both methods was not significant (γ = 0.29). Mean LVEFJud was 63.9 ± 17.4%, which was not significantly different from LVEFnuc, with a fair correlation (γ = 0.55). Mean LVEFimp was 59.2 ± 9.4%, with a better correlation with radionuclide ventriculography (γ = 0.75).Conclusions. The results of this study indicate that the equations that have been used until now can be improved. The new equation provides reliable LVEF values in this group of patients.

Miltefosine is an alkylphosphocholine drug with demonstrated activity against various parasite species and cancer cells as well as some pathogenic bacteria and fungi. For 10 years it has been licensed in India for the treatment of visceral leishmaniasis (VL), a fatal neglected parasitic disease. It is the first and still the only oral drug that can be used to treat VL and cutaneous leishmaniasis (CL). The standard 28 day miltefosine monotherapy regimen is well tolerated, except for mild gastrointestinal side effects, although its teratogenic potential severely hampers its general use in the clinic and roll-out in national elimination programmes. The pharmacokinetics of miltefosine are mainly characterized by its long residence time in the body, resulting in extensive drug accumulation during treatment and long elimination half-lives. At the moment, different combination therapy strategies encompassing miltefosine are being tested in multiple controlled clinical trials in various geographical areas of endemicity, both in South Asia and East Africa. We here review the most salient pre-clinical and clinical pharmacological aspects of miltefosine, its mechanism of action against Leishmania parasites and other pathogens, and provide a systematic overview of the efficacy and safety data from all clinical trials of miltefosine, either alone or in combination, in the treatment of VL and CL.

The aim of this study was to assess the applicability and benefits of the new WHO dengue fever guidelines in clinical practice, for returning travellers.We compared differences in specificity and sensitivity between the old and the new guidelines for diagnosing dengue and assessed the usefulness in predicting the clinical course of the disease. Also, we investigated whether hypertension, diabetes or allergies, ethnicity or high age influenced the course of disease.In our setting, the old classification, compared with the new, had a marginally higher sensitivity for diagnosing dengue. The new classification had a slightly higher specificity and was less rigid. Patients with dengue who had warning signs as postulated in the new classification were admitted more often than those who had no warning signs (RR, 8.09 [1.80-35.48]). We did not find ethnicity, age, hypertension, diabetes mellitus or allergies to be predictive of the clinical course.In our cohort of returned travellers, the new classification system did not differ in sensitivity and specificity from the old system to a clinically relevant degree. The guidelines did not improve identification of severe disease.

Proper chemotherapy is pivotal in the management of visceral leishmaniasis (VL, also known as kala-azar); without an effective treatment this neglected parasitic disease is inevitably fatal [1]. Nevertheless, the few new and safer but more expensive treatment options that were developed in the past decade (i.e., liposomal amphotericin B and miltefosine) remain largely out of reach of the affected rural population who are most in need, mainly the poorest of the poor [2]–[4]. Miltefosine, an alkylphosphocholine drug, is an essential drug in the management of VL as it is the first effective oral treatment option with a reasonable safety profile [5]. Oral miltefosine allows the treatment of VL patients without an extended period of hospital admission and thus puts fewer demands on both patients and health services [6], [7]. Miltefosine is currently preferred for implementation in national VL elimination programmes [8], although the burden of high treatment costs incites the exploration of possibilities for a generic miltefosine product [9]. Unfortunately, the precarious position of VL patients was recently jeopardized as patients in Bangladesh were confronted with a new threat: the emergence of a new miltefosine product containing no active pharmaceutical ingredient [10], [11].

Use of miltefosine in the treatment of visceral leishmaniasis (VL) is hampered by its potential teratogenicity. The duration of adequate contraceptive cover in females of child-bearing potential after cessation of a potentially teratogenic drug therapy remains debated. The objective of this study was to provide a rational approach to suggest durations of contraceptive cover for various miltefosine regimens.A human reproductive safety threshold exposure limit was derived using animal-to-human dose conversion. Pharmacokinetic (PK) data for miltefosine in females are lacking; a previously developed population PK model and a comprehensive anthropometric dataset were used to simulate PK data for Indian female VL patients receiving miltefosine for 5, 7, 10 or 28 days. Probability of supra-threshold miltefosine exposure was used to evaluate adequate durations of post-treatment contraceptive cover for the various regimens.PK data were simulated for 465 treated Indian female VL patients of child-bearing potential with a median age of 25 years (IQR 16-31 years) and median weight of 38 kg (IQR 34-42 kg). From animal reproductive toxicity studies, a human reproductive safety threshold exposure limit was derived of 24.5 μg · day/mL. Probability of 'unprotected' supra-threshold miltefosine exposure was very low (0.2%) for a post-treatment contraceptive cover period of 4 months for the standard 28 day regimen, and of 2 months for the shorter regimens.To our knowledge, this is the first study providing rational suggestions for contraceptive cover for a teratogenic drug based on animal-to-human dose conversion. For the 28 day miltefosine regimen, post-treatment contraceptive cover may be extended to 4 months, whereas for all shorter regimens 2 months may be adequate.

Orphan drugs are drugs used in the treatment of life-threatening or chronic diseases that affect fewer than 1 out of 2000 persons in the European Union. Since the implementation of the European Regulation on Orphan Medicinal Products in 2000, 61 orphan drugs have been brought to market. One-third of these were granted their marketing authorisations based on non-comparative clinical research. Certain orphan drugs for extramural use will be transferred to the performance-based hospital financing system within the next few years. Unapproved orphan drugs are generally not reimbursed. In so-called compassionate use programmes, unauthorised orphan drugs can still become available to patients who do not participate in clinical trials. Compassionate use drugs are made available by the manufacturer.

Background Intravenous (IV) artesunate is the treatment of choice for severe malaria. In Europe, however, no GMP-manufactured product is available and treatment data in European travellers are scarce. Fortunately, artesunate became available in the Netherlands and Belgium through a named patient programme. This is the largest case series of artesunate treated patients with severe malaria in Europe. Methods Hospitalized patients treated with IV artesunate between November 2007 and December 2010 in the Netherlands and Belgium were retrospectively evaluated. Patient characteristics, treatment and clinical outcome were recorded on a standardized form and mortality, parasite clearance times and the occurrence of adverse events were evaluated. Results Of the 68 treated patients, including 55 with severe malaria, two patients died (2/55 = 3.6%). The mean time to 50% parasite clearance (PCT50), 90% and 99% were 4.4 hours (3.9 - 5.2), 14.8 hours (13.0 - 17.2), and 29.5 hours (25.9 - 34.4) respectively. Artesunate was well tolerated. However, an unusual form of haemolytic anaemia was observed in seven patients. The relationship with artesunate remains uncertain. Conclusions Data from the named patient programme demonstrate that IV artesunate is effective and well-tolerated in European travellers lacking immunity. However, increased attention needs to be paid to the possible development of haemolytic anaemia 2-3 weeks after start of treatment. Treatment of IV artesunate should be limited to the period that IV treatment is required and should be followed by a full oral course of an appropriate anti-malarial drug.

Recently, it was revealed that generic miltefosine capsules for the treatment of visceral leishmaniasis, a fatal parasitic disease, were possibly counterfeit products. Here we report on the methods to characterize and identify miltefosine in pharmaceutical products and the procedures that were used to assess the quality of these suspected counterfeit products. Characterization and identification of miltefosine were done with liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), Fourier transform infrared (FT-IR) spectroscopy and near-infrared (NIR) spectroscopy. Moreover, a simple, rapid and inexpensive colorimetric test was developed and evaluated for the detection of miltefosine in pharmaceutical products that can be used in the field. The complementary analytical techniques presented here were able to determine qualitatively or (semi-)quantitatively the presence or absence of miltefosine in pharmaceutical preparations and could identify suspected counterfeit miltefosine capsules. This finding of a suspected counterfeit drug intended to treat a neglected disease in a resource-poor country emphasizes the urgent need to develop more simple inexpensive assays to evaluate drug quality for use in the field.

BACKGROUND: Treatment of HIV/malaria-coinfected patients with antiretroviral therapy (ART) and artemisinin-based combination therapy has potential for drug interactions. We investigated the pharmacokinetics of artemether, dihydroartemisinin and lumefantrine after administration of a single dose of 80/480 mg of artemether/lumefantrine to HIV-infected adults, taken with and without lopinavir/ritonavir. METHODS: A two-arm parallel study of 13 HIV-infected ART-naive adults and 16 HIV-infected adults stable on 400/100 mg of lopinavir/ritonavir plus two nucleoside reverse transcriptase inhibitors (ClinicalTrials.gov, NCT 00619944). Each participant received a single dose of 80/480 mg of artemether/lumefantrine under continuous cardiac function monitoring. Plasma concentrations of artemether, dihydroartemisinin and lumefantrine were measured. RESULTS: Co-administration of artemether/lumefantrine with lopinavir/ritonavir significantly reduced artemether maximum concentration (C(max)) and area under the concentration-time curve (AUC) [median (range): 112 (20-362) versus 56 (17-236) ng/mL, P = 0.03; and 264 (92-1129) versus 151 (38-606) ng · h/mL, P < 0.01]. Dihydroartemisinin C(max) and AUC were not affected [66 (10-111) versus 73 (31-224) ng/mL, P = 0.55; and 213 (68-343) versus 175 (118-262) ng · h/mL P = 0.27]. Lumefantrine C(max) and AUC increased during co-administration [2532 (1071-5957) versus 7097 (2396-9462) ng/mL, P < 0.01; and 41,119 (12,850-125,200) versus 199,678 (71,205-251,015) ng · h/mL, P < 0.01]. CONCLUSIONS: Co-administration of artemether/lumefantrine with lopinavir/ritonavir significantly increases lumefantrine exposure, but decreases artemether exposure. Population pharmacokinetic and pharmacodynamic trials will be highly valuable in evaluating the clinical significance of this interaction and determining whether dosage modifications are indicated.

OBJECTIVES: Co-administration of artemether/lumefantrine with antiretroviral therapy has potential for pharmacokinetic drug interactions. We investigated drug-drug interactions between artemether/lumefantrine and efavirenz or nevirapine. METHODS: We performed a cross-over study in which HIV-infected adults received standard six-dose artemether/lumefantrine 80/480 mg before and at efavirenz or nevirapine steady state. Artemether, dihydroartemisinin, lumefantrine, efavirenz and nevirapine plasma concentrations were measured and compared. RESULTS: Efavirenz significantly reduced artemether maximum concentration (C(max)) and plasma AUC (median 29 versus 12 ng/mL, P

Objective: To measure maternal and fetal hemodynamics during acute malaria in pregnancy. Methods: Time courses of maternal heart rate (MHR), maternal blood pressure (BP), and fetal heart rate (FHR) were performed until 56 days after initiation of anti-malarial treatment with artemether-lumefantrine. Women with malaria were hospitalized for at least 3 days until recovery. Results: Mean baseline characteristics of pregnant women with malaria (n =38) versus pregnant women without malaria (n = 39) were as follows: gestational age (28.8 vs 24.6 weeks: P = 0.006); maximum FHR (165.3 vs 158.3 beats per minute [bpm]; P = 0.054); minimum FHR (137.6 vs 128.7 bpm; P = 0.016); mean BP (74.7 vs 80.9 mm Hg; P = 0.001); pulse pressure (40.3 vs 42.1 mm Hg; P = 0.300): and MHR (107.4 vs 81.3 bpm; P

Parasite loads were quantified in repeated skin biopsies from lesions of 2 patients with Old-World cutaneous leishmaniasis (CL) caused by Leishmania major and L. infantum during and after treatment with miltefosine. Miltefosine induced a rapid therapeutic effect on both infections with an initial decline of parasites of ∼1 log/week for the L. major infection. These observations illustrate the usability of quantifying parasite loads in skin lesions as a pharmacodynamic measure and quantitative descriptor of drug effect for CL supporting clinical assessment., Author Summary The clinical evaluation of the ulcerated lesions in cutaneous leishmaniasis (CL) is both difficult and subjective. As a result, the evaluation of therapeutic efficacy of drugs for CL remains complicated. The relationship between dose and effect of antileishmanial drugs in CL is unclear and a good quantitative descriptor of drug effect has not yet been established. This report describes the use of quantifying the parasite load in repeated full-thickness skin biopsies from lesions of two patients with extensive Old-World CL (Leishmania major and L. infantum) who both were treated with miltefosine to demonstrate the dynamics of parasite clearance within CL lesions. Therapeutic effect of miltefosine was already noticeable directly after start of treatment, with a rapid, log-linear decline in parasite load in the skin biopsies of approximately 1 log/week for the L. major infection. These observations illustrate the applicability of quantifying parasite loads as a pharmacodynamic measure for CL supporting clinical assessment. The methodology described here might enable better evaluation and comparison of standard and new therapeutics in future randomized clinical trials for CL.

Rapid and fast acting anti-malarials are essential to treat severe malaria. Quinine has been the only option for parenteral therapy until recently. While current evidence shows that intravenous artesunate is more effective than quinine in treating severe malaria in endemic countries, some questions remain regarding safety profiles and drug resistance. For imported severe malaria, additional unanswered questions are related to generalizability of the findings from endemic countries and to legal aspects, as there is no Good Manufacturing Practice-conform drug available yet. Here, the implications of existing evidence for the treatment of imported severe malaria are discussed.

Dengue has become a global public health problem and a sensitive diagnostic test for early phase detection can be life saving. An internally controlled, generic real-time PCR was developed and validated by testing serial dilutions of a DENV positive control RNA in the presence of a fixed amount of IC with results showing a good linearity (R2=0.9967) and a LOD of at least1.95×104 copies/mL. Application of the generic PCR on 136 patient samples revealed a sensitivity of 95.8% and specificity of 100%. A newly developed multiplex real-time PCR with serotype-specific probes allowed the serotyping of DENV for 80 out of 92 (87%) generic real-time PCR positive patients. Combined these real-time PCRs offer a convenient diagnostic tool for the sensitive and specific quantification of DENV in clinical specimens with the possibility for serotyping.

Background: This study aims to estimate the age-specific risks of clinical dengue attack (i.e., the risk of symptomatic dengue among the total number of dengue virus (DENV) infections) during primary and secondary infections. Methods: We analyzed two pieces of epidemiological information in Binh Thuan province, southern Vietnam, i.e., age-specific seroprevalence and a community-wide longitudinal study of clinical dengue attack. The latter data set stratified febrile patients with DENV infection by age as well as infection parity. A simple modeling approach was employed to estimate the age-specific risks of clinical dengue attack during primary and secondary infections. Results: Using the seroprevalence data, the force of infection was estimated to be 11.7% (95% confidence intervals (CI): 10.8-12.7) per year. Median age (and the 25-75 percentiles) of dengue fever patients during primary and secondary infections were 12 (9-20) and 20 (14-31) years, respectively. The estimated age-specific risk of clinical dengue increases as a function of age for both primary and secondary infections; the estimated proportion of symptomatic patients among the total number of infected individuals was estimated to be, link_to_subscribed_fulltext

African tick-bite fever (ATBF) is frequently diagnosed in The Netherlands in travelers returning from South Africa. It is caused by Rickettsia africae and diagnosis is based on travel history and clinical presentation and usually confirmed by detecting serum antibodies against rickettsiae of the spotted fever group. However, these typically occur late in the course of the disease, and a mild clinical course or early antibiotic treatment can diminish antibody production. Four travelers presented with (sub)febrile temperatures and eschar(s), several days after returning from South Africa. R. africae DNA was amplified and sequenced from skin biopsies of the eschars of all patients. Initial immunofluorescence assays yielded no immunoglobulin M (IgM)/IgG antibodies directed against spotted fever group rickettsiae; however, serology in the convalescent phase-several weeks after the patients had fully recovered-was positive. ATBF should be considered in travelers returning from South Africa to The Netherlands with febrile illness and (multiple) skin lesions. The diagnosis can be confirmed by (paired) serology; however, polymerase chain reaction and sequencing on skin biopsies could be a (faster and more accurate) confirmatory test. Advantages of molecular methods over serology are species identification and high sensitivity early in the course of the disease

Cutaneous leishmaniasis caused by Leishmania major infection affected 172 (18.3%) of 938 Dutch military troops deployed in northern Afghanistan in 2005. The high attack rate was a result of initial insufficient availability of means of prevention and insufficient adherence to preventive measures. At presentation, the lymphatic system was involved in 24.8%. Treatment with intralesional injections of antimony with or without cryotherapy was satisfactory, but 19.5% of patients received secondary treatment with miltefosine. Six months after treatment, 128 (77.1%) of 166 treated patients were cured, 16 (9.6%) were lost to follow-up, and 22 (13.3%) already experienced cure at six weeks but were not seen at six months. Natural evolution played a role in this observational study, which showed cure of all patients seen at six months. In general, management of cutaneous leishmaniasis was feasible under field conditions.

To investigate the proportion of viral respiratory tract infections among acute undifferentiated fevers (AUFs) at primary health facilities in southern Vietnam during 2001-2005, patients with AUF not caused by malaria were enrolled at twelve primary health facilities and a clinic for malaria control program. Serum was collected on first presentation (t0) and after 3 weeks (t3) for serology. After exclusion of acute dengue infection, acute and convalescent serum samples from 606 patients were using enzyme-linked immunoassays to detect IgA, as well as IgM and IgG antibodies against common respiratory viruses. Paired sera showed the following infections: human parainfluenza virus (HPIV, 4.7%), influenza B virus (FLUBV, 2.2%), influenza A virus (FLUAV, 1.9%) and human respiratory syncytial virus (HRSV, 0.6%). There was no association between type of infection and age, sex or seasonality; some inter-annual differences were observed for influenza. Antibody prevalence, indicative of previous infections, was relatively low: HPV, 56.8%, FLUBV, 12.1%; FLUAV, 5.9% and HRSV, 6.8%.

Background Dengue is a major global public health problem with increasing incidence and geographic spread. The epidemiology is complex with long inter-epidemic intervals and endemic with seasonal fluctuations. This study was initiated to investigate dengue transmission dynamics in Binh Thuan province, southern Vietnam. Methodology Wavelet analyses were performed on time series of monthly notified dengue cases from January 1994 to June 2009 (i) to detect and quantify dengue periodicity, (ii) to describe synchrony patterns in both time and space, (iii) to investigate the spatio-temporal waves and (iv) to associate the relationship between dengue incidence and El Niño-Southern Oscillation (ENSO) indices in Binh Thuan province, southern Vietnam. Principal Findings We demonstrate a continuous annual mode of oscillation and a multi-annual cycle of around 2–3-years was solely observed from 1996–2001. Synchrony in time and between districts was detected for both the annual and 2–3-year cycle. Phase differences used to describe the spatio-temporal patterns suggested that the seasonal wave of infection was either synchronous among all districts or moving away from Phan Thiet district. The 2–3-year periodic wave was moving towards, rather than away from Phan Thiet district. A strong non-stationary association between ENSO indices and climate variables with dengue incidence in the 2–3-year periodic band was found. Conclusions A multi-annual mode of oscillation was observed and these 2–3-year waves of infection probably started outside Binh Thuan province. Associations with climatic variables were observed with dengue incidence. Here, we have provided insight in dengue population transmission dynamics over the past 14.5 years. Further studies on an extensive time series dataset are needed to test the hypothesis that epidemics emanate from larger cities in southern Vietnam., Author Summary Dengue has become a major international public health problem due to increasing geographic distribution and a transition from epidemic transmission with long inter-epidemic intervals to endemic transmission with seasonal fluctuation. Seasonal and multi-annual cycles in dengue incidence vary over time and space. We performed wavelet analyses on time series of monthly notified dengue cases in Binh Thuan province, southern Vietnam, from January 1994 to June 2009. We observed a continuous annual mode of oscillation with a non-stationary 2–3-year multi-annual cycle. We used phase differences to describe the spatio-temporal patterns which suggest that the seasonal wave of infection was either synchronous with all districts or moving away from Phan Thiet district, while the multi-annual wave of infection was moving towards Phan Thiet district. We also found a strong non-stationary association between ENSO indices and climate variables with dengue incidence. We provided insight in dengue population transmission dynamics over the past 14.5 years. Further studies on an extensive time series dataset are needed to test the hypothesis that epidemics emanate from larger cities in southern Vietnam.