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A highly drug resistant malaria "superbug" from western Cambodia is now present in southern Vietnam, leading to alarming failure rates for dihydroartemisinin (DHA)-piperaquine — Vietnam’s national first-line malaria treatment, leading malaria scientists warn.
A common form of dominant human IFNAR1 deficiency impairs IFN-α and -ω but not IFN-β-dependent immunity.
Autosomal recessive deficiency of the IFNAR1 or IFNAR2 chain of the human type I IFN receptor abolishes cellular responses to IFN-α, -β, and -ω, underlies severe viral diseases, and is globally very rare, except for IFNAR1 and IFNAR2 deficiency in Western Polynesia and the Arctic, respectively. We report 11 human IFNAR1 alleles, the products of which impair but do not abolish responses to IFN-α and -ω without affecting responses to IFN-β. Ten of these alleles are rare in all populations studied, but the remaining allele (P335del) is common in Southern China (minor allele frequency ≈2%). Cells heterozygous for these variants display a dominant phenotype in vitro with impaired responses to IFN-α and -ω, but not -β, and viral susceptibility. Negative dominance, rather than haploinsufficiency, accounts for this dominance. Patients heterozygous for these variants are prone to viral diseases, attesting to both the dominance of these variants clinically and the importance of IFN-α and -ω for protective immunity against some viruses.
Detection of Mycoplasma pneumoniae in hospitalized children with pneumonia in Laos
Mycoplasma pneumoniae has been described worldwide as an important cause of community-acquired pneumonia. From December 2013 to December 2014, 461 children admitted to Mahosot Hospital, Vientiane, Laos, with acute respiratory infection were investigated for upper respiratory microorganisms using probe-based real-time polymerase chain reaction (PCR) (FTD33). M. pneumoniae was detected by FTD33 in the upper respiratory tract of three patients, two girls and one boy, 5.7 and 3.9 years old and 13.6 years old, respectively. They presented with clinical features compatible with M. pneumoniae infection. They improved without M. pneumoniae directed therapy. The two girls were also positive for other potential pathogens. The boy had abnormal pulmonary auscultation, and one of the girls had significant anaemia. These results suggest that enhancement of diagnostic systems for M. pneumoniae detection is needed to improve understanding of the epidemiology of M. pneumoniae infection in Laos.
Case Report: Genetic evolution of Burkholderia pseudomallei during treatment leading to antibiotic resistance and disease relapse – a case report.
Background Melioidosis is a significant yet neglected cause of sepsis in tropical regions, particularly in southeast Asia, with poor clinical outcomes. It is a growing threat with an expanding global footprint. The causative organism, Burkholderia pseudomallei, is intrinsically resistant to most first-line empiric antibiotic regimens, but acquired resistance to recommended antibiotics for this infection is uncommon. Nonetheless, the genetic determinants of resistance in this species remain poorly elucidated. Case presentation A 60-year-old farmer presented in septic shock to a hospital in Laos, and B. pseudomallei was grown from blood cultures. Following initial antibiotic treatment with meropenem and co-trimoxazole, his infection relapsed. Several subsequent B. pseudomallei isolates from the patient were resistant to multiple antibiotics, and whole genome sequencing demonstrated that this phenotype was associated with a novel 54-kb genomic deletion. This deletion, on chromosome 1, includes the 5’ end of amrR – which encodes a regulator of an efflux pump known to be important in conferring meropenem resistance – as well as 46 other genes, some of which have not been characterised. Treatment was targeted to the new antibiogram, requiring a further prolonged intravenous course and second-line oral eradication therapy. The patient made a full recovery. Conclusions Mutations in Burkholderia pseudomallei lead to increased virulence and drug resistance. Repeat microbiological sampling of patients who do not make clinical improvement as anticipated is essential, with repeat full antimicrobial susceptibility testing on subsequent isolates. Characterisation of drug-resistant mutants is required to understand mechanisms of resistance and to predict phenotypes from whole genome sequencing.
Molnupiravir or nirmatrelvir-ritonavir plus usual care versus usual care alone in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial.
BackgroundMolnupiravir and nirmatrelvir-ritonavir are oral antivirals that have shown efficacy in preventing disease progression in outpatients with COVID-19. We aimed to evaluate these treatments for patients hospitalised with COVID-19 pneumonia, for whom data on these antivirals are scarce.MethodsThe RECOVERY trial is a randomised, controlled, open-label, adaptive platform trial testing treatments for COVID-19. In this study we report the molnupiravir and nirmatrelvir-ritonavir comparisons from the RECOVERY trial. In each comparison, participants aged 18 years and older were randomly allocated (1:1) to the relevant antiviral (5 days of molnupiravir 800 mg twice daily or 300 mg nirmatrelvir and 100 mg ritonavir twice daily) in addition to usual care, or to usual care alone. The molnupiravir comparison was conducted at 75 hospitals in the UK, two in Nepal, and two in Indonesia; the nirmatrelvir-ritonavir comparison was conducted at 32 hospitals in the UK. Participants could take part in both comparisons. The primary outcome was 28-day mortality, and secondary outcomes were time to discharge alive from hospital and progression to invasive ventilation or death. Analysis was by intention to treat. Both comparisons were stopped because of low recruitment. This study is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.FindingsFrom Jan 24, 2022, to May 24, 2023, 923 participants were recruited to the molnupiravir comparison (445 allocated to molnupiravir and 478 to usual care), and from March 31, 2022, to May 24, 2023, 137 participants were recruited to the nirmatrelvir-ritonavir comparison (68 allocated to nirmatrelvir-ritonavir and 69 to usual care). More than three-quarters of participants were vaccinated and had antispike antibodies at randomisation, and more than two-thirds were receiving other SARS-CoV-2 antivirals. In the molnupiravir comparison, 74 (17%) participants allocated to molnupiravir and 79 (17%) allocated to usual care died within 28 days (hazard ratio [HR] 0·93 [95% CI 0·68-1·28], p=0·66). In the nirmatrelvir-ritonavir comparison, 13 (19%) participants allocated to nirmatrelvir-ritonavir and 13 (19%) allocated to usual care died within 28 days (HR 1·02 [0·47-2·23], p=0·96). In neither comparison was there evidence of any difference in the duration of hospitalisation or the proportion of participants progressing to invasive ventilation or death.InterpretationAdding molnupiravir or nirmatrelvir-ritonavir to usual care was not associated with improvements in clinical outcomes. However, low recruitment meant a clinically meaningful benefit of treatment could not be ruled out, particularly for nirmatrelvir-ritonavir.FundingUK Research and Innovation (UK Medical Research Council), the National Institute for Health and Care Research, and the Wellcome Trust.
Migrant women's experience of antenatal care in an urban and rural setting in north and North-West Thailand: A cross sectional survey
Background: Nearly 50 % of women in low- and middle-income countries fail to obtain adequate antenatal care due to barriers in reaching the health facility. A key element of the quality of care is women's perception of treatment they receive. This study aims to compare the perspectives of urban and rural migrant women from Myanmar in Thailand and the obstacles they face when trying to access care. Methods: From October-2023 to May-2024, a survey was conducted among migrant women, 74 at Sarapee hospital in Chang Mai Province, and 148 at the clinics of Shoklo Malaria Research Unit (SMRU), Tak Province. Questions based on REPRO-Q were used for scoring satisfaction in several domains using a Likert scale ranging from dissatisfied to satisfied. Results: The majority of women in Sarapee and SMRU reported pleasant visits, 86.5 % (64/74), 99.3 % (144/145) respectively. Disrespectful behaviour against migrant women was low and mentioned by 14.9 % (11/74) in Sarapee and 1.4 % (2/148) at SMRU. The women attending care at Sarapee reported significantly lower satisfaction 60.8 % (45/74) on being able to refuse examination or treatment compared to women attending care in SMRU 83.0 % (122/147) P < 0.001. Conclusion: Both urban and rural settings had high rates of perceived pleasant visits and recommending the service to friends, although this could result from hesitancy to give negative feedback. At this critical stage of the life course both institutions can improve, to eliminate experiences of perceived disrespectful behavior.
Temporal correlations between RBD-ACE2 blocking and binding antibodies to SARS-CoV-2 variants in CoronaVac-vaccinated individuals and their persistence in COVID-19 patients.
Antibodies play a crucial role in protection against SARS-CoV-2. Understanding the correlation between binding and functional antibodies is essential to determine whether binding antibody levels can reliably predict neutralizing activity. We assessed antibody responses in 111 individuals vaccinated with the inactivated vaccine CoronaVac and 111 COVID-19 patients in Thailand. Plasma levels of ACE2-blocking antibodies targeting the receptor-binding domain (RBD) of SARS-Co-V2 variants were measured before vaccination and at 14 and 28 days after the second dose using a multiplex surrogate virus neutralization test. Anti-spike and anti-nucleocapsid antibodies were quantified by electrochemiluminescence immunoassay, and anti-RBD IgG by ELISA. After vaccination, blocking, anti-spike, and IgG antibody levels increased but declined rapidly within a month, whereas antibody levels in COVID-19 patients increased and persisted. Blocking and anti-spike antibody correlated at day 14 post-vaccination but not at day 28. In COVID-19 patients, correlations were moderate at day 14, and stronger at day 28. Correlations were weaker for Omicron subvariants than for the ancestral strain and non-Omicron variants. The weak correlation between blocking and anti-RBD IgG suggests binding antibodies might not predict neutralizing activity. These findings highlight the temporal nature of CoronaVac-induced immunity and the need for booster doses and variant-adapted vaccine.
Safety and efficacy of single-dose primaquine to interrupt Plasmodium falciparum malaria transmission in children compared with adults: a systematic review and individual patient data meta-analysis.
BackgroundAdding a single dose of primaquine to artemisinin-based combination therapy (ACT) for the treatment of falciparum malaria can reduce the transmission of Plasmodium falciparum and could limit the spread of artemisinin partial resistance, including in Africa, where the disease burden is greatest. We aimed to compare the safety and efficacy of single-dose primaquine plus ACT between young children (aged <5 years) and older children (aged 5 years to <15 years) and adults (aged ≥15 years), and between low and moderate-to-high transmission areas.MethodsFor this systematic review and individual patient data meta-analysis, we searched PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, WHO Global Index Medicus, OpenGrey.eu, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform, from database inception to April 3, 2024, with no language restrictions. We included prospective studies on efficacy against falciparum malaria that enrolled at least one child younger than 15 years and involved a study group given a single dose of primaquine (≤0·75 mg/kg) plus ACT. Studies involving mass drug administration, healthy volunteers, or patients with severe malaria or mixed (with non-falciparum) infections were excluded. For inclusion in the efficacy analysis, data on transmission potential (as determined by gametocytaemia, infectivity, or both) at enrolment and follow-up (day 3, day 7, or day 14) were required; the safety analysis required data on haemoglobin concentrations or haematocrit values at enrolment and at one or more follow-up visits by day 7, any data on adverse events, or both. After independent screening of the search results by two reviewers, the investigators of eligible studies were invited to contribute individual patient data. We quantified day 7 gametocyte carriage, probability of infecting a mosquito, decreases (>25%) in haemoglobin concentration associated with anaemia, and adverse events until day 28 using regression analyses, with random study-site intercepts to account for clustered data. These analyses were registered with PROSPERO, CRD42021279363 (safety) and CRD42021279369 (efficacy).FindingsOf 5697 records identified by the search, 30 studies were eligible for analysis. Of these, individual patient data were shared for 23 studies, including 6056 patients from 16 countries: 1171 (19·3%) young children (aged <5 years), 2827 (46·7%) older children (aged 5 years to <15 years), and 2058 (34·0%) adults (aged ≥15 years). Adding a single low dose of primaquine (0·2-0·25 mg/kg) to ACTs reduced day 7 gametocyte positivity (adjusted odds ratio [aOR] 0·34, 95% CI 0·22-0·52; p<0·001) and infectivity to mosquitoes over time (aOR per day 0·02, 0·01-0·07, p<0·001). No difference was found in the effect of single low-dose primaquine both on gametocyte positivity in young children compared with older children (1·08, 0·52-2·23; p=0·84) and adults (0·50, 0·20-1·25; p=0·14) and between low-transmission and moderate-to-high transmission settings (1·07, 0·46-2·52; p=0·86), and on infectivity to mosquitoes in young children compared with older children (1·36, 0·07-27·71; p=0·84) and adults (0·31, 0·01-8·84; p=0·50) and between low-transmission and moderate-to-high transmission settings (0·18, 0·01-2·95; p=0·23). Gametocyte clearance was also similar for different ACTs (dihydroartemisinin-piperaquine vs artemether-lumefantrine) when combined with a primaquine target dose of 0·25 mg/kg (1·56, 0·65-3·79; p=0·32 at day 7). However, patients given a primaquine dose of less than 0·2 mg/kg with dihydroartemisinin-piperaquine were more likely to have gametocytaemia than those treated with artemether-lumefantrine (5·68, 1·38-23·48; p=0·016 at day 7). There was no increase in anaemia-associated declines in haemoglobin concentration (>25%) at a primaquine dose of 0·25 mg/kg, regardless of age group, transmission setting, and glucose-6-phosphate dehydrogenase status. The risks of adverse events of grade 2 or higher and of serious adverse events were similar between primaquine and no-primaquine groups, including in young children.InterpretationRegardless of malaria transmission intensity and age group, a single dose of 0·25 mg/kg primaquine is safe and efficacious for reducing P falciparum transmission. These findings underscore the need for primaquine formulations suitable for young children, and also provide supportive evidence to expand the use of single low-dose primaquine in regions with a moderate-to-high transmission rate that are threatened by artemisinin partial resistance.FundingThe EU and the Bill & Melinda Gates Foundation.
Leptospirosis, melioidosis, and rickettsioses in the vicious circle of neglect
The global priorities in the field of infectious diseases are constantly changing. While emerging viral infections have regularly dominated public health attention, which has only intensified after the COVID-19 pandemic, numerous bacterial diseases have previously caused, and continue to cause, significant morbidity and mortality—deserving equal attention. Three potentially life-threatening endemic bacterial diseases (leptospirosis, melioidosis, and rickettsioses) are a huge public health concern especially in low- and middle-income countries. Despite their continued threat, these diseases do not receive proportionate attention from global health organizations and are not even included on the WHO list of neglected tropical diseases (NTDs). This, in turn, has led to a vicious circle of neglect with continued, yet conceivably preventable, hospitalizations and deaths each year especially in the vulnerable population. This is a call from a group of multi-institutional experts on the urgent need to directly address the circle of neglect and raise support in terms of funding, research, surveillance, diagnostics, and therapeutics to alleviate the burden of these 3 diseases.
Experiences, perceptions and ethical considerations of the malaria infection study in Thailand.
BackgroundThailand has made significant progress in malaria control efforts in the past decade, with a decline in the number of reported cases. However, due to cross-border movements over the past 5 years, reported malaria cases in Thailand have risen. The Malaria Infection Study in Thailand (MIST) involves deliberate infection of healthy volunteers with Plasmodium vivax malaria parasites, and the assessment of the efficacy of potential vaccine and drug candidates in order to understand acquired protection against malaria parasites.MethodsThis paper drew from ethics and social science qualitative study called MIST-ETHICS embedded within the MIST studies. MIST-ETHICS aimed to describe and understand the experiences, perceptions and ethical considerations of the MIST studies. Data were obtained from semi-structured interviews and a focus group discussion. A total of 46 participants participated in MIST-ETHICS .ResultsThree major themes emerged: experiences and perceptions of MIST, reasons for joining MIST, and ethical considerations. We found that although compensation was a motivation for participation, this was secondary to it being beneficial to self (health checks; link to health networks; building merit) and others (medical research contribution; altruism). Participants expressed varied opinions regarding the requirement of a university degree as one of the inclusion criteria for MIST.ConclusionsOur study revealed widespread concerns about long-term health effects and safety. Ethical considerations, including obtaining valid informed consent and ensuring participant inclusivitiy, were deem essential. Despite some debate regarding eligibility criteria, most participants agreed that the informed consent process was robust, accompanied by a strong sense of responsibility to contribute to the greater good. We emphasize the importance of continuously gathering participants' feedback for quality control, such as improving information materials to clarify the purpose of initial phases, their contributing to later phases, and the rationale behind each selection criterion.Trial registrationThis manuscript is part of the clinical trials registered under ClinicalTrials.gov IDs NCT04083508 (MIST1) registered on 5 Sep 2019 and NCT05071079 (MIST2) registered on 28 July 2021. However, the manuscript pertains to a qualitative study that does not require trial registration.
Comparing HemoCue® and Quantitative Buffy Coat® and Coulter Counter-measured haemoglobin concentrations in African children with acute uncomplicated malaria: a Bland-Altman analysis.
BackgroundAnaemia is a deleterious consequence of malaria, and its accurate diagnosis is crucial for effective management. However, laboratory methods for measuring haemoglobin (Hb) concentration, like the Coulter Counter and the Quantitative Buffy Coat® (QBC®), are costly and not widely accessible in resource-limited settings. The point-of-care HemoCue® test is a cheaper alternative and suitable in rural areas. The study aimed to determine the level of agreement between Coulter Counter/QBC® vs. HemoCue®-measured Hb concentrations by Bland-Altman analysis.MethodsAs part of a randomized, placebo-controlled trial of single low-dose primaquine in Ugandan and Congolese children with acute uncomplicated Plasmodium falciparum malaria, Hb concentrations were measured on days 0, 3, 7, and 28 using Coulter Counter (Uganda, n = 1880 paired values), QBC® (DR Congo, n = 1984 paired values) and HemoCue® Hb-301™. The predefined clinically acceptable limits were set at ± 0.5 g/dL.ResultsThe Bland-Altman analysis showed that the HemoCue® minus Coulter Counter mean Hb difference was - 0.15 g/dL with lower and upper limits of agreement of - 3.68 g/dL and 3.39 g/dL, respectively. Corresponding HemoCue® minus QBC® values were - 0.23 g/dL, - 1.66 g/dL and 1.22 g/dL. Linear regression of Hb concentration differences vs. mean Hb concentrations showed negative correlations: r = - 0.43 and r = - 0.34 for HemoCue® vs. Coulter Counter and HemoCue® vs. QBC®, respectively.ConclusionsCompared to Coulter and QBC®, mean HemoCue® measured Hb concentrations were lower and, compared to the Coulter or QBC® methods, had an overall tendency to measure lower Hb concentrations with increasing Hb concentrations. Upper and lower limits of agreement were wider than the predefined clinically acceptable limits of ± 0.5 g/dL. HemoCue® should be used with caution in settings where decisions about blood transfusions are made.
Advancing artemisinin resistance monitoring using a high sensitivity ddPCR assay for Pfkelch13 mutation detection in Asia.
The spread of Pfkelch13 mutations in Southeast Asia threatens the effectiveness of artemisinin-based combination therapies (ACTs) for malaria. Previous studies revealed a high prevalence of key mutations, including C580Y, P574L, and R561H, emphasizing the need for the surveillance to combat drug resistance. This study, we developed a droplet digital PCR (ddPCR) assay for the rapid screening of common mutations including P441L, Y493H, P527H, G538V, R539T, I543T, R561H, P574L, C580Y, and A675V. The assay was designed to detect minor populations of mutant strain within multiple infection, offering high sensitivity and specificity using artificial mixtures of mutant and wild-type alleles. Field samples collected in Thailand during 2015-2020 and in 2023 (N = 130) were also analyzed to validate the assay in a real-world setting. The ddPCR assay demonstrated exceptional performance, with 100% sensitivity and 90% specificity. The R539T, R561H, and C580Y mutations were detected in clinical samples collected from several study sites in Thailand. Notably, the R561H mutation was detected in 100% of the P. falciparum isolates from Mae Hong Son, Thailand in 2023, underscoring the assay's utility in identifying critical mutations associated with drug resistance. Moreover, ddPCR can detect multiple parasite populations in clinical samples and can be used to analyze the ratios of wild-type and mutant alleles. These results validate the assay's ability to serve as a powerful tool for the early detection of minor allele frequencies, facilitating the timely implementation of interventions to curb the spread of ACT resistance. The ddPCR assays developed in this study provide a sensitive and specific method for detecting Pfkelch13 mutations, allowing the identification of minor parasite populations with artemisinin resistance. These assays enhance our ability to monitor and respond to malaria drug resistance, offering a crucial tool for early detection and contributing to global malaria elimination efforts.
Bringing the real world into the classroom through team-based live brief projects
Team-based project work in higher education provides opportunities to enhance collaborative learning, to strengthen students' academic skills in a work-related context, and to instil valuable transferable skills that relate to the modern workplace. This chapter explores existing literature on live briefs, their relevance to graduate employability, and how the involvement of external stakeholders can bring real-world experience into the classroom as part of a social constructivist approach to learning. Alongside an analysis of the different approaches documented in the literature, Live Brief examples are presented from a final-year undergraduate Computing and Software Engineering learning context within a higher education Institution based in England. The pedagogical underpinnings, benefits, ethical considerations, and challenges of live briefs are discussed along with other factors such as the value of student-staff-stakeholder partnerships, the importance of collaboration between academia and industry, potential applications of Generative Artificial Intelligence (GenAI), and the power of Social and Emotional Learning (SEL) through engagement with social issues.