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1.
Lancet Infect Dis ; 22(3): 377-389, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1839424

ABSTRACT

BACKGROUND: WHO recently approved a partially effective vaccine that reduces clinical malaria in children, but increased vaccine activity is required to pursue malaria elimination. A phase 1 clinical trial was done in Mali, west Africa, to assess the safety, immunogenicity, and protective efficacy of a three-dose regimen of Plasmodium falciparum sporozoite (PfSPZ) Vaccine (a metabolically active, non-replicating, whole malaria sporozoite vaccine) against homologous controlled human malaria infection (CHMI) and natural P falciparum infection. METHODS: We recruited healthy non-pregnant adults aged 18-50 years in Donéguébougou, Mali, and surrounding villages (Banambani, Toubana, Torodo, Sirababougou, Zorokoro) for an open-label, dose-escalation pilot study and, thereafter, a randomised, double-blind, placebo-controlled main trial. Pilot study participants were enrolled on an as-available basis to one group of CHMI infectivity controls and three staggered vaccine groups receiving: one dose of 4·5 × 105, one dose of 9 × 105, or three doses of 1·8 × 106 PfSPZ via direct venous inoculation at approximately 8 week intervals, followed by homologous CHMI 5 weeks later with infectious PfSPZ by direct venous inoculation (PfSPZ Challenge). Main cohort participants were stratified by village and randomly assigned (1:1) to receive three doses of 1·8 × 106 PfSPZ or normal saline at 1, 13, and 19 week intervals using permuted block design by the study statistician. The primary outcome was safety and tolerability of at least one vaccine dose; the secondary outcome was vaccine efficacy against homologous PfSPZ CHMI (pilot study) or against naturally transmitted P falciparum infection (main study) measured by thick blood smear. Combined artesunate and amodiaquine was administered to eliminate pre-existing parasitaemia. Outcomes were analysed by modified intention to treat (mITT; including all participants who received at least one dose of investigational product; safety and vaccine efficacy) and per protocol (vaccine efficacy). This trial is registered with ClinicalTrials.gov, number NCT02627456. FINDINGS: Between Dec 20, 2015, and April 30, 2016, we enrolled 56 participants into the pilot study (five received the 4·5 × 105 dose, five received 9 × 105, 30 received 1·8 × 106, 15 were CHMI controls, and one withdrew before vaccination) and 120 participants into the main study cohort with 60 participants assigned PfSPZ Vaccine and 60 placebo in the main study. Adverse events and laboratory abnormalities post-vaccination in all dosing groups were few, mainly mild, and did not differ significantly between vaccine groups (all p>0·05). Unexpected severe transaminitis occured in four participants: one participant in pilot phase that received 1·8 × 106 PfSPZ Vaccine, one participant in main phase that received 1·8 × 106 PfSPZ Vaccine, and two participants in the main phase placebo group. During PfSPZ CHMI, approximately 5 weeks after the third dose of 1·8 × 106 PfSPZ, none of 29 vaccinees and one of 15 controls became positive on thick blood smear; subsequent post-hoc PCR analysis for submicroscopic blood stage infections detected P falciparum parasites in none of the 29 vaccine recipients and eight of 15 controls during CHMI. In the main trial, 32 (58%) of 55 vaccine recipients and 42 (78%) of 54 controls became positive on thick blood smear during 24-week surveillance after vaccination. Vaccine efficacy (1-hazard ratio) was 0·51 per protocol (95% CI 0·20-0·70; log-rank p=0·0042) and 0·39 by mITT (0·04-0·62; p=0·033); vaccine efficacy (1-risk ratio) was 0·24 per-protocol (0·02-0·41; p=0·031) and 0·22 mITT (0·01-0·39; p=0·041). INTERPRETATION: A three-dose regimen of PfSPZ Vaccine was safe, well tolerated, and conferred 51% vaccine efficacy against intense natural P falciparum transmission, similar to 52% vaccine efficacy reported for a five-dose regimen in a previous trial. FUNDING: US National Institute of Allergy and Infectious Diseases, National Institutes of Health, Sanaria. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Subject(s)
Malaria Vaccines , Malaria, Falciparum , Malaria , Adolescent , Adult , Animals , Child , Double-Blind Method , Humans , Malaria/drug therapy , Malaria, Falciparum/drug therapy , Mali , Middle Aged , Pilot Projects , Plasmodium falciparum , Seasons , Sporozoites , Young Adult
2.
Malar J ; 21(1): 121, 2022 Apr 12.
Article in English | MEDLINE | ID: covidwho-1789122

ABSTRACT

Malaria is one of the most serious infectious diseases affecting predominantly low- and middle-income countries, where pregnant women are among the populations at risk. There are limited options to prevent or treat malaria in pregnancy, particularly in the first trimester, and existing ones may not work optimally in areas where the threat of drug resistance is rising. As malaria elimination is a key goal of the global health community, the inclusion of pregnant women in the adult population to protect from malaria will be key to achieving success. New, safe, and effective options are needed but it can take decades of evidence-gathering before a medicine is recommended for use in pregnancy. This is because pregnant women are typically not included in pre-registration clinical trials due to fear of causing harm. Data to support dosing and safety in pregnancy are subsequently collected in post-licensure studies. There have been growing calls in recent years that this practice needs to change, amplified by the COVID-19 pandemic and increasing public awareness that newly developed medicines generally cannot be administered to pregnant women from the onset. The development of new anti-malarials should ensure that data informing their use in pregnancy and breastfeeding are available earlier. To achieve this, a mindset change and a different approach to medications for pregnant women are needed. Changes in non-clinical, translational, and clinical approaches in the drug development pathway, in line with recent recommendations from the regulatory bodies are proposed in this Comment. The new approach applies to any malaria-endemic region, regardless of the type of Plasmodium responsible for malaria cases. By incorporating intentional and systematic data collection from pre-registration stages of development through post-licensure, it will be possible to inform on the benefit/risk balance of a new anti-malarial earlier and help ensure that the needs of pregnant individuals are addressed in a more timely and equitable manner in the future.


Subject(s)
Antimalarials , COVID-19 , Malaria , Adult , Antimalarials/therapeutic use , Drug Development , Female , Humans , Malaria/drug therapy , Malaria/epidemiology , Malaria/prevention & control , Pandemics , Pregnancy , Pregnant Women
3.
OMICS ; 26(4): 179-188, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1784298

ABSTRACT

Coronavirus disease 2019 (COVID-19) is a systemic disease, impacting multiple organs in the human body. But COVID-19 also impacts other diseases of relevance to public and planetary health. To understand and respond to the COVID-19 pandemic, we need an intersectional conceptual lens and systems thinking. For example, the strain on health care systems due to COVID-19 has adversely impacted global malaria elimination programs. With many epidemiological, clinical, and biological parallels documented, we examined in this study the scenario of malaria and COVID-19 syndemic in India. The disruptive influence of COVID-19 on the National Framework for Malaria Elimination (NFME), impact of unintended chemoprophylaxis, population genetic influences, and the shifting patterns of epidemiology are compared. Importantly, a time series analysis forecasted the burden of malaria increasing in the upcoming years. Although reported malaria cases showed a decline in 2020 compared to the previous years, an increase in cases was documented in 2021, with nine states reporting an increase up to July 2021. Pandemics often cause crosscutting disruptions in health care. Reshaping the priorities of the malaria elimination program and a diligent implementation of the priorities in the NFME would, therefore, be well-advised: (1) vector control, (2) antimalarial therapy recommendations, (3) monitoring drug resistance, (4) prevention of the spread of asymptomatic disease-causing low-density transmission, and (5) large-scale testing measures. In conclusion, the findings from the present study inform future comparative studies in other world regions to better understand the broader, systemic, temporal, and spatial impacts of the COVID-19 pandemic on existing and future diseases across public health systems and services.


Subject(s)
Antimalarials , COVID-19 , Malaria , Antimalarials/therapeutic use , COVID-19/epidemiology , Humans , Malaria/epidemiology , Malaria/prevention & control , Pandemics/prevention & control , Population Surveillance
4.
Front Public Health ; 9: 742378, 2021.
Article in English | MEDLINE | ID: covidwho-1775900

ABSTRACT

Despite the scale-up of vector control, diagnosis and treatment, and health information campaigns, malaria persists in the forested areas of South-Central Vietnam, home to ethnic minority populations. A mixed-methods study using an exploratory sequential design was conducted in 10 Ra-glai villages in Bac Ai district of Ninh Thuan province to examine which social factors limited the effectiveness of the national malaria elimination strategy in the local setting. Territorial arrangements and mobility were found to directly limit the effectiveness of indoor residual spraying and long-lasting insectidical treated nets (LLINs). Households (n=410) were resettled in the "new villages" by the government, where they received brick houses (87.1%) and sufficient LLINs (97.3%). However, 97.6% of households went back to their "old villages" to continue slash-and-burn agriculture. In the old village, 48.5% of households lived in open-structured plot huts and only 5.7% of them had sufficient LLIN coverage. Household representatives believed malaria could be cured with antimalarials (57.8%), but also perceived non-malarial medicines, rituals, and vitamin supplements to be effective against malaria. Household members (n = 1,957) used public health services for their most recent illness (62.9%), but also reported to buy low-cost medicines from the private sector to treat fevers and discomfort as these were perceived to be the most cost-effective treatment option for slash-and-burn farmers. The study shows the relevance of understanding social factors to improve the uptake of public health interventions and calls for contextually adapted strategies for malaria elimination in ethnic minority populations in Vietnam and similar settings.


Subject(s)
Malaria , Humans , Malaria/drug therapy , Malaria/prevention & control , Minority Groups , Vietnam/epidemiology
5.
BMJ Open ; 12(3): e053922, 2022 Mar 31.
Article in English | MEDLINE | ID: covidwho-1774956

ABSTRACT

OBJECTIVES: Malaria is a vector-borne disease that remains a serious public health problem due to its climatic sensitivity. Accurate prediction of malaria re-emergence is very important in taking corresponding effective measures. This study aims to investigate the impact of climatic factors on the re-emergence of malaria in mainland China. DESIGN: A modelling study. SETTING AND PARTICIPANTS: Monthly malaria cases for four Plasmodium species (P. falciparum, P. malariae, P. vivax and other Plasmodium) and monthly climate data were collected for 31 provinces; malaria cases from 2004 to 2016 were obtained from the Chinese centre for disease control and prevention and climate parameters from China meteorological data service centre. We conducted analyses at the aggregate level, and there was no involvement of confidential information. PRIMARY AND SECONDARY OUTCOME MEASURES: The long short-term memory sequence-to-sequence (LSTMSeq2Seq) deep neural network model was used to predict the re-emergence of malaria cases from 2004 to 2016, based on the influence of climatic factors. We trained and tested the extreme gradient boosting (XGBoost), gated recurrent unit, LSTM, LSTMSeq2Seq models using monthly malaria cases and corresponding meteorological data in 31 provinces of China. Then we compared the predictive performance of models using root mean squared error (RMSE) and mean absolute error evaluation measures. RESULTS: The proposed LSTMSeq2Seq model reduced the mean RMSE of the predictions by 19.05% to 33.93%, 18.4% to 33.59%, 17.6% to 26.67% and 13.28% to 21.34%, for P. falciparum, P. vivax, P. malariae, and other plasmodia, respectively, as compared with other candidate models. The LSTMSeq2Seq model achieved an average prediction accuracy of 87.3%. CONCLUSIONS: The LSTMSeq2Seq model significantly improved the prediction of malaria re-emergence based on the influence of climatic factors. Therefore, the LSTMSeq2Seq model can be effectively applied in the malaria re-emergence prediction.


Subject(s)
Deep Learning , Malaria, Falciparum , Malaria , China/epidemiology , Climate Change , Humans , Malaria/epidemiology
6.
Malar J ; 21(1): 103, 2022 Mar 24.
Article in English | MEDLINE | ID: covidwho-1759754

ABSTRACT

BACKGROUND: Seasonal malaria chemoprevention (SMC) is a WHO-recommended intervention for children aged 3-59 months living in areas of high malaria transmission to provide protection against malaria during the rainy season. Operational guidelines were developed, based on WHO guidance, to support countries to mitigate the risk of coronavirus disease 2019 (COVID-19) transmission within communities and among community distributors when delivering SMC. METHODS: A cross-sectional study to determine adherence to infection prevention and control (IPC) measures during two distribution cycles of SMC in Nigeria, Chad and Burkina Faso. Community distributors were observed receiving equipment and delivering SMC. Adherence across six domains was calculated as the proportion of indications in which the community distributor performed the correct action. Focus group discussions were conducted with community distributors to understand their perceptions of the IPC measures and barriers and facilitators to adherence. RESULTS: Data collectors observed community distributors in Nigeria (n = 259), Burkina Faso (n = 252) and Chad (n = 266) receiving IPC equipment and delivering SMC. Adherence to IPC indications varied. In all three countries, adherence to mask use was the highest (ranging from 73.3% in Nigeria to 86.9% in Burkina Faso). Adherence to hand hygiene for at least 30 s was low (ranging from 3.6% in Nigeria to 10.3% in Burkina Faso) but increased substantially when excluding the length of time spent hand washing (ranging from 36.7% in Nigeria to 61.4% in Burkina Faso). Adherence to safe distancing in the compound ranged from 5.4% in Chad to 16.4% in Nigeria. In Burkina Faso and Chad, where disinfection wipes widely available compliance with disinfection of blister packs for SMC was low (17.4% in Burkina Faso and 16.9% in Chad). Community distributors generally found the IPC measures acceptable, however there were barriers to optimal hand hygiene practices, cultural norms made social distancing difficult to adhere to and caregivers needed assistance to administer the first dose of SMC. CONCLUSION: Adherence to IPC measures for SMC delivery during the COVID-19 pandemic varied across domains of IPC, but was largely insufficient, particularly for hand hygiene and safe distancing. Improvements in provision of protective equipment, early community engagement and adaptations to make IPC measures more feasible to implement could increase adherence.


Subject(s)
Antimalarials , COVID-19 , Malaria , Antimalarials/therapeutic use , Burkina Faso/epidemiology , COVID-19/prevention & control , Chad , Chemoprevention , Child , Child, Preschool , Cross-Sectional Studies , Humans , Infant , Malaria/prevention & control , Nigeria/epidemiology , Pandemics/prevention & control , Seasons
9.
Int J Environ Res Public Health ; 19(6)2022 03 16.
Article in English | MEDLINE | ID: covidwho-1742478

ABSTRACT

According to the latest World Health Organization malaria report, 95% of 241 million global malaria cases and 96% of 627,000 malaria deaths that were recorded in 2020 occurred in Africa. Compared to 2019, 14 million more cases and 69,000 more malaria deaths were recorded, mainly because of disruptions to medical services during the COVID-19 pandemic. The aim of this study was to assess the prevalence of asymptomatic malaria cases in children and adults living in the Dzanga Sangha region in the Central African Republic (CAR) during the COVID-19 pandemic. Rapid immunochromatographic assays for the qualitative detection of Plasmodium species (P. falciparum, P. vivax, P. ovale/P. malariae) circulating in whole blood samples were used. A screening was performed in the group of 515 patients, 162 seemingly healthy children (aged 1-15) and 353 adults, all inhabiting the villages in the Dzanga Sangha region (southwest CAR) between August and September 2021. As much as 51.2% of asymptomatic children and 12.2% of adults had a positive result in malaria rapid diagnostic tests (mRDTs). Our findings demonstrated a very high prevalence of asymptomatic malaria infections in the child population. Limited access to diagnostics, treatment and prevention of malaria during the global COVID-19 pandemic and less medical assistance from developed countries may be one of the factors contributing to the increase in the prevalence of disease in Africa.


Subject(s)
COVID-19 , Malaria , Adolescent , Adult , COVID-19/epidemiology , Central African Republic/epidemiology , Child , Child, Preschool , Humans , Infant , Malaria/epidemiology , Pandemics , Plasmodium falciparum
11.
Int J Environ Res Public Health ; 19(5)2022 02 23.
Article in English | MEDLINE | ID: covidwho-1736891

ABSTRACT

The conventional paper-based system for malaria surveillance is time-consuming, difficult to track and resource-intensive. Few digital platforms are in use but wide-scale deployment and acceptability remain to be seen. To address this issue, we created a malaria surveillance mobile app that offers real-time data to stakeholders and establishes a centralised data repository. The MoSQuIT app was designed to collect data from the field and was integrated with a web-based platform for data integration and analysis. The MoSQuIT app was deployed on mobile phones of accredited social health activists (ASHA) working in international border villages in the northeast (NE) Indian states of Assam, Tripura and Arunachal Pradesh for 20 months in a phased manner. This paper shares the challenges and opportunities associated with the use of MoSQuIT for malaria surveillance. MoSQuIT employs the same data entry formats as the NVBDCP's malaria surveillance programme. Using this app, a total of 8221 fever cases were recorded, which included 1192 (14.5%) cases of P. falciparum malaria, 280 (3.4%) cases of P. vivax malaria and 52 (0.6%) mixed infection cases. Depending on network availability, GPS coordinates of the fever cases were acquired by the app. The present study demonstrated that mobile-phone-based malaria surveillance facilitates the quick transmission of data from the field to decision makers. Geospatial tagging of cases helped with easy visualisation of the case distribution for the identification of malaria-prone areas and potential outbreaks, especially in hilly and remote regions of Northeast India. However, to achieve the full operational potential of the system, operational challenges have to be overcome.


Subject(s)
Malaria, Falciparum , Malaria, Vivax , Malaria , Mobile Applications , Telemedicine , Fever , Humans , India/epidemiology , Malaria/epidemiology , Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology
13.
Biosensors (Basel) ; 12(2)2022 Feb 11.
Article in English | MEDLINE | ID: covidwho-1715106

ABSTRACT

Despite being preventable and treatable, malaria still puts almost half of the world's population at risk. Thus, prompt, accurate and sensitive malaria diagnosis is crucial for disease control and elimination. Optical microscopy and immuno-rapid tests are the standard malaria diagnostic methods in the field. However, these are time-consuming and fail to detect low-level parasitemia. Biosensors and lab-on-a-chip devices, as reported to different applications, usually offer high sensitivity, specificity, and ease of use at the point of care. Thus, these can be explored as an alternative for malaria diagnosis. Alongside malaria infection inside the human red blood cells, parasites consume host hemoglobin generating the hemozoin crystal as a by-product. Hemozoin is produced in all parasite species either in symptomatic and asymptomatic individuals. Furthermore, hemozoin crystals are produced as the parasites invade the red blood cells and their content relates to disease progression. Hemozoin is, therefore, a unique indicator of infection, being used as a malaria biomarker. Herein, the so-far developed biosensors and lab-on-a-chip devices aiming for malaria detection by targeting hemozoin as a biomarker are reviewed and discussed to fulfil all the medical demands for malaria management towards elimination.


Subject(s)
Hemeproteins , Malaria , Biomarkers , Erythrocytes/parasitology , Erythrocytes/physiology , Hemeproteins/metabolism , Humans , Malaria/blood , Malaria/diagnosis , Malaria/parasitology
15.
BMC Public Health ; 22(1): 373, 2022 02 21.
Article in English | MEDLINE | ID: covidwho-1700500

ABSTRACT

BACKGROUND: Despite efforts to avert the negative effects of malaria, there remain barriers to the uptake of prevention measures, and these have hindered its eradication. This study explored the factors that influence uptake of malaria prevention strategies among pregnant women and children under-five years and the impact of COVID-19 in a malaria endemic rural district in Uganda. METHODS: This was a qualitative case study that used focus group discussions, in-depth interviews, and key informant interviews involving pregnant women, caregivers of children under-five years, traditional birth attendants, village health teams, local leaders, and healthcare providers to explore malaria prevention uptake among pregnant women and children under-five years. The interviews were audio-recorded, transcribed and data were analyzed using thematic content approach. RESULTS: Seventy-two participants were enrolled in the Focus Group Discussions, 12 in the in-depth interviews, and 2 as key informants. Pregnant women and caregivers of children under-five years were able to recognize causes of malaria, transmission, and symptoms. All participants viewed malaria prevention as a high priority, and the use of insecticide-treated mosquito bed nets (ITNs) was upheld. Participants' own experiences indicated adverse effects of malaria to both pregnant women and children under-five. Home medication and the use of local herbs were a common practice. Some participants didn't use any of the malaria prevention methods due to deliberate refusal, perceived negative effects of the ITNs, and family disparity. The Corona Virus Disease-2019 (COVID-19) control measures did not abate the risk of malaria infection but these were deleterious to healthcare access and the focus of malaria prevention. CONCLUSIONS: Although pregnant women and caregivers of children under-five years recognized symptoms of malaria infection, healthcare-seeking was not apt as some respondents used alternative approaches and delayed seeking formal healthcare. It is imperative to focus on the promotion of malaria prevention strategies and address drawbacks associated with misconceptions about these interventions, and promotion of health-seeking behaviors. As COVID-19 exacerbated the effect of malaria prevention uptake and healthcare seeking, it's critical to recommit and integrate COVID-19 prevention measures in normative living and restrict future barriers to healthcare access.


Subject(s)
COVID-19 , Malaria , Caregivers , Child , Female , Health Knowledge, Attitudes, Practice , Humans , Malaria/drug therapy , Malaria/epidemiology , Malaria/prevention & control , Pandemics , Pregnancy , Pregnant Women , Rural Population , SARS-CoV-2 , Uganda/epidemiology
16.
Malar J ; 21(1): 48, 2022 Feb 14.
Article in English | MEDLINE | ID: covidwho-1686016

ABSTRACT

BACKGROUND: Rwanda has achieved impressive reductions in malaria morbidity and mortality over the past two decades. However, the disruption of essential services due to the current Covid-19 pandemic can lead to a reversal of these gains in malaria control unless targeted, evidence-based interventions are implemented to mitigate the impact of the pandemic. The extent to which malaria services have been disrupted has not been fully characterized. This study was conducted to assess the impact of Covid-19 on malaria services in Rwanda. METHODS: A mixed-methods study was conducted in three purposively selected districts in Rwanda. The quantitative data included malaria aggregated data reported at the health facility level and the community level. The data included the number of malaria tests, uncomplicated malaria cases, severe malaria cases, and malaria deaths. The qualitative data were collected using focus group discussions with community members and community health workers, as well as in-depth interviews with health care providers and staff working in the malaria programme. Interrupted time series analysis was conducted to compare changes in malaria presentations between the pre-Covid-19 period (January 2019 to February 2020) and Covid-19 period (from March 2020 to November 2020). The constant comparative method was used in qualitative thematic analysis. RESULTS: Compared to the pre-Covid-19 period, there was a monthly reduction in patients tested in health facilities of 4.32 per 1000 population and a monthly increase in patients tested in the community of 2.38 per 1000 population during the Covid-19 period. There was no change in the overall presentation rate for uncomplicated malaria. The was a monthly reduction in the proportion of severe malaria of 5.47 per 100,000 malaria cases. Additionally, although healthcare providers continued to provide malaria services, they were fearful that this would expose them and their families to Covid-19. Covid-19 mitigation measures limited the availability of transportation options for the community to seek care in health facilities and delayed the implementation of some key malaria interventions. The focus on Covid-19-related communication also reduced the amount of health information for other diseases provided to community members. CONCLUSION: The Covid-19 pandemic resulted in patients increasingly seeking care in the community and poses challenges to maintaining delivery of malaria services in Rwanda. Interventions to mitigate these challenges should focus on strengthening programming for the community and home-based care models and integrating malaria messages into Covid-19-related communication. Additionally, implementation of the interrupted interventions should be timed and overlap with the malaria transmission season to mitigate Covid-19 consequences on malaria.


Subject(s)
COVID-19 , Malaria , Community Health Workers , Humans , Malaria/epidemiology , Malaria/prevention & control , Pandemics , Rwanda/epidemiology , SARS-CoV-2
17.
Anal Bioanal Chem ; 414(8): 2607-2618, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1653432

ABSTRACT

The lateral flow assay (LFA) is one of the most popular technologies on the point-of-care diagnostics market due to its low cost and ease of use, with applications ranging from pregnancy to environmental toxins to infectious disease. While the use of these tests is relatively straightforward, significant development time and effort are required to create tests that are both sensitive and specific. Workflows to guide the LFA development process exist but moving from target selection to an LFA that is ready for field testing can be labor intensive, resource heavy, and time consuming. To reduce the cost and the duration of the LFA development process, we introduce a novel development platform centered on the flexibility, speed, and throughput of an automated robotic liquid handling system. The system comprises LFA-specific hardware and software that enable large optimization experiments with discrete and continuous variables such as antibody pair selection or reagent concentration. Initial validation of the platform was demonstrated during development of a malaria LFA but was readily expanded to encompass development of SARS-CoV-2 and Mycobacterium tuberculosis LFAs. The validity of the platform, where optimization experiments are run directly on LFAs rather than in solution, was based on a direct comparison between the robotic system and a more traditional ELISA-like method. By minimizing hands-on time, maximizing experiment size, and enabling improved reproducibility, the robotic system improved the quality and quantity of LFA assay development efforts.


Subject(s)
COVID-19/diagnosis , Immunoassay/instrumentation , Malaria/diagnosis , Point-of-Care Testing , Tuberculosis/diagnosis , COVID-19 Serological Testing/economics , COVID-19 Serological Testing/instrumentation , Equipment Design , Humans , Immunoassay/economics , Mycobacterium tuberculosis/isolation & purification , Plasmodium/isolation & purification , Point-of-Care Testing/economics , Reproducibility of Results , SARS-CoV-2/isolation & purification , Sensitivity and Specificity , Time Factors
18.
Emerg Infect Dis ; 28(2): 440-444, 2022 02.
Article in English | MEDLINE | ID: covidwho-1650669

ABSTRACT

Inhabitants of the Greater Mekong Subregion in Cambodia are exposed to pathogens that might influence serologic cross-reactivity with severe acute respiratory syndrome coronavirus 2. A prepandemic serosurvey of 528 malaria-infected persons demonstrated higher-than-expected positivity of nonneutralizing IgG to spike and receptor-binding domain antigens. These findings could affect interpretation of large-scale serosurveys.


Subject(s)
COVID-19 , Malaria , Antibodies, Viral , Cambodia/epidemiology , Humans , Malaria/epidemiology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
19.
BMC Infect Dis ; 22(1): 78, 2022 Jan 22.
Article in English | MEDLINE | ID: covidwho-1643116

ABSTRACT

BACKGROUND: Despite reports of malaria and coronavirus diseases 2019 (COVID-19) co-infection, malaria-endemic regions have so far recorded fewer cases of COVID-19 and deaths from COVID-19, indicating a probable protection from the poor outcome of COVID-19 by malaria. On the contrary, other evidence suggests that malaria might contribute to the death caused by COVID-19. Hence, this paper reviewed existing evidence hypothesizing poor outcome or protection of COVID-19 patients when co-infected with malaria. METHODS: PRISMA guidelines for systematic review were employed in this study. Published articles from December 2019 to May 2021on COVID-19 and malaria co-infection and outcome were systematically searched in relevant and accessible databases following a pre-defined strategy. Studies involving human, in vivo animal studies, and in vitro studies were included. RESULTS: Twenty three (23) studies were included in the review out of the 3866 records identified in the selected scientific databases. Nine (9) papers reported on co-infection of COVID-19 and malaria. Five (5) papers provided information about synergism of malaria and COVID-19 poor prognosis, 2 papers reported on syndemic of COVID-19 and malaria intervention, and 7 studies indicated that malaria protects individuals from COVID-19. CONCLUSIONS: Low incidence of COVID-19 in malaria-endemic regions supports the hypothesis that COVID-19 poor prognosis is prevented by malaria. Although further studies are required to ascertain this hypothesis, cross-immunity and common immunodominant isotopes provide strong evidence to support this hypothesis. Also, increase in co-inhibitory receptors and atypical memory B cells indicate synergy between COVID-19 and malaria outcome, though, more studies are required to make a definite conclusion.


Subject(s)
COVID-19 , Coinfection , Malaria , Africa/epidemiology , Animals , Coinfection/epidemiology , Humans , Incidence , Malaria/complications , Malaria/epidemiology , SARS-CoV-2
20.
Malar J ; 20(1): 475, 2021 Dec 20.
Article in English | MEDLINE | ID: covidwho-1635854

ABSTRACT

BACKGROUND: In March 2020, the government of Uganda implemented a strict lockdown policy in response to the COVID-19 pandemic. Interrupted time series analysis (ITSA) was performed to assess whether major changes in outpatient attendance, malaria burden, and case management occurred after the onset of the COVID-19 epidemic in rural Uganda. METHODS: Individual level data from all outpatient visits collected from April 2017 to March 2021 at 17 facilities were analysed. Outcomes included total outpatient visits, malaria cases, non-malarial visits, proportion of patients with suspected malaria, proportion of patients tested using rapid diagnostic tests (RDTs), and proportion of malaria cases prescribed artemether-lumefantrine (AL). Poisson regression with generalized estimating equations and fractional regression was used to model count and proportion outcomes, respectively. Pre-COVID trends (April 2017-March 2020) were used to predict the'expected' trend in the absence of COVID-19 introduction. Effects of COVID-19 were estimated over two six-month COVID-19 time periods (April 2020-September 2020 and October 2020-March 2021) by dividing observed values by expected values, and expressed as ratios. RESULTS: A total of 1,442,737 outpatient visits were recorded. Malaria was suspected in 55.3% of visits and 98.8% of these had a malaria diagnostic test performed. ITSA showed no differences between observed and expected total outpatient visits, malaria cases, non-malarial visits, or proportion of visits with suspected malaria after COVID-19 onset. However, in the second six months of the COVID-19 time period, there was a smaller mean proportion of patients tested with RDTs compared to expected (relative prevalence ratio (RPR) = 0.87, CI (0.78-0.97)) and a smaller mean proportion of malaria cases prescribed AL (RPR = 0.94, CI (0.90-0.99)). CONCLUSIONS: In the first year after the COVID-19 pandemic arrived in Uganda, there were no major effects on malaria disease burden and indicators of case management at these 17 rural health facilities, except for a modest decrease in the proportion of RDTs used for malaria diagnosis and the mean proportion of malaria cases prescribed AL in the second half of the COVID-19 pandemic year. Continued surveillance will be essential to monitor for changes in trends in malaria indicators so that Uganda can quickly and flexibly respond to challenges imposed by COVID-19.


Subject(s)
Ambulatory Care , COVID-19/epidemiology , Malaria/epidemiology , Chronic Disease Indicators , Humans , Infection Control , Interrupted Time Series Analysis , Malaria/diagnosis , Malaria/therapy , Malaria/transmission , Rural Health , Uganda/epidemiology
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