Excess mortality in Europe coincides with peaks of COVID-19, influenza and respiratory syncytial virus (RSV), November 2023 to February 2024

Since the end of November 2023, the European Mortality Monitoring Network (EuroMOMO) has observed excess mortality in Europe. During weeks 48 2023-6 2024, preliminary results show a substantially increased rate of 95.3 (95% CI:  91.7-98.9) excess all-cause deaths per 100,000 person-years for all ages. This excess mortality is seen in adults aged 45 years and older, and coincides with widespread presence of COVID-19, influenza and respiratory syncytial virus (RSV) observed in many European countries during the 2023/24 winter season.

Age-dependent influenza infection patterns and subtype circulation in Denmark, in seasons 2015/16 to 2021/22

BackgroundInfluenza was almost absent for 2 years following the implementation of strict public health measures to prevent the spread of SARS-CoV-2. The consequence of this on infections in different age groups is not yet known.AimTo describe the age groups infected with the influenza virus in 2021/22, the first post-pandemic influenza season in Denmark, compared with the previous six seasons, and subtypes circulating therein.MethodsInfection and hospitalisation incidences per season and age group were estimated from data in Danish registries. Influenza virus subtypes and lineages were available from samples sent to the National Influenza Centre at Statens Serum Institut.ResultsTest incidence followed a similar pattern in all seasons, being highest in 0-1-year-olds and individuals over 75 years, and lowest in 7-14-year-olds and young people 15 years to late twenties. When the influenza A virus subtypes A(H3N2) and A(H1N1)pdm09 co-circulated in seasons 2015/16 and 2017/18 to 2019/20, the proportion of A(H1N1)pdm09 was higher in 0-1-year-olds and lower in the over 85-year-olds  compared with the overall proportion of A(H1N1)pdm09 in these seasons. The proportion of A(H3N2) was higher in the over 85 years age group compared with the overall proportion of A(H3N2). The 2016/17 and 2021/22 seasons were dominated by A(H3N2) but differed in age-specific trends, with the over 85 years age group initiating the 2016/17 season, while the 2021/22 season was initiated by the 15-25-year-olds, followed by 7-14-year-olds.ConclusionThe 2021/22 influenza season had a different age distribution compared with pre-COVID-19 pandemic seasons.

Frequency of pleural effusion in dengue patients by severity, age and imaging modality: a systematic review and meta-analysis

BACKGROUND

Identification of pleural effusion (PE) in dengue infection is an objective measure of plasma leakage and may predict disease progression. However, no studies have systematically assessed the frequency of PE in patients with dengue, and whether this differs across age and imaging modality.

METHODS

We searched Pubmed, Embase Web of Science and Lilacs (period 1900-2021) for studies reporting on PE in dengue patients (hospitalized and outpatient). We defined PE as fluid in the thoracic cavity detected by any imaging test. The study was registered in PROSPERO (CRD42021228862). Complicated dengue was defined as hemorrhagic fever, dengue shock syndrome or severe dengue.

RESULTS

The search identified 2,157 studies of which 85 studies were eligible for inclusion. The studies (n = 31 children, n = 10 adults, n = 44 mixed age) involved 12,800 patients (30% complicated dengue). The overall frequency of PE was 33% [95%CI: 29 to 37%] and the rate of PE increased significantly with disease severity (P = 0.001) such that in complicated vs. uncomplicated dengue the frequencies were 48% and 17% (P < 0.001). When assessing all studies, PE occurred significantly more often in children compared to adults (43% vs. 13%, P = 0.002) and lung ultrasound more frequently detected PE than conventional chest X-ray (P = 0.023).

CONCLUSIONS

We found that 1/3 of dengue patients presented with PE and the frequency increased with severity and younger age. Importantly, lung ultrasound demonstrated the highest rate of detection. Our findings suggest that PE is a relatively common finding in dengue and that bedside imaging tools, such as lung ultrasound, potentially may enhance detection.

COVID-19 mortality attenuated during widespread Omicron transmission, Denmark, 2020 to 2022

BackgroundIt sparked considerable attention from international media when Denmark lifted restrictions against COVID-19 in February 2022 amidst widespread transmission of the new SARS-CoV-2 Omicron variant and a steep rise in reported COVID-19 mortality based on the 30-day COVID-19 death count.AimOur aim was to investigate how coincidental infections affected COVID-19 mortality estimates following the introduction of the Omicron variant in late 2021.MethodsWe compared the 30-day COVID-19 death count with the observed mortality using three alternative mortality estimation methods; (i) a mathematical model to correct the 30-day COVID-19 death count for coincidental deaths, (ii) the Causes of Death Registry (CDR) and (iii) all-cause excess mortality.ResultsThere was a substantial peak in the 30-day COVID-19 death count following the emergence of the Omicron variant in late 2021. However, there was also a substantial change in the proportion of coincidental deaths, increasing from 10-20% to around 40% of the recorded COVID-19 deaths. The high number of 30-day COVID-19 deaths was not reflected in the number of COVID-19 deaths in the CDR and the all-cause excess mortality surveillance.ConclusionOur analysis showed a distinct change in the mortality pattern following the introduction of Omicron in late 2021 with a markedly higher proportion of people estimated to have died with, rather than of, COVID-19 compared with mortality patterns observed earlier in the COVID-19 pandemic. Our findings highlight the importance of incorporating alternative mortality surveillance methods to more correctly estimate the burden of COVID-19 as the pandemic continues to evolve.

Early and intense epidemic of respiratory syncytial virus (RSV) in Denmark, August to December 2022

In the autumn of 2022, Denmark witnessed the second out-of-season epidemic of respiratory syncytial virus (RSV) following widespread societal preventive measures implemented against the coronavirus disease (COVID-19) pandemic during 2020 and 2021. Admissions peaked at twice the level of pre-pandemic seasons. Especially infants below 6 months of age were affected, but also adults over 45 years of age. The current epidemic is dominated by RSV subtype B, unlike the major RSV summer epidemic in 2021 dominated by RSV subtype A.

Severe Human Case of Zoonotic Infection with Swine-Origin Influenza A Virus, Denmark, 2021

During routine surveillance at the National Influenza Center, Denmark, we detected a zoonotic swine influenza A virus in a patient who became severely ill. We describe the clinical picture and the genetic characterization of this variant virus, which is distinct from another variant found previously in Denmark.

Potential role of transthoracic echocardiography for screening LV systolic dysfunction in patients with a history of dengue infection. A cross-sectional and cohort study and review of the literature

Background

Dengue virus can affect the cardiovascular system and men may be at higher risk of severe complications than women. We hypothesized that clinical dengue virus (DENV) infection could induce myocardial alterations of the left ventricle (LV) and that these changes could be detected by transthoracic echocardiography.

Methodology/Principal findings

We examined individuals from Acre in the Amazon Basin of Brazil in 2020 as part of the Malaria Heart Study. By questionnaires we collected information on self-reported prior dengue infection. All individuals underwent transthoracic echocardiography, analysis of left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS). We included 521 persons (mean age 40±15 years, 39% men, 50% urban areas) of which 253 (49%) had a history of dengue infection. In multivariable models adjusted for clinical and sociodemographic data, a history of self-reported dengue was significantly associated with lower LVEF (β = -2.37, P < 0.01) and lower GLS (β = 1.08, P < 0.01) in men, whereas no significant associations were found in women (P > 0.05). In line with these findings, men with a history of dengue had higher rates of LV systolic dysfunction (LVEF < 50% = 20%; GLS < 16% = 17%) than those without a history of dengue (LVEF < 50% = 7%; GLS < 16% = 8%; P < 0.01 and 0.06, respectively).

Conclusions/Significance

The findings of this study suggest that a clinical infection by dengue virus could induce myocardial alterations, mainly in men and in the LV, which could be detected by conventional transthoracic echocardiography. Hence, these results highlight a potential role of echocardiography for screening LV dysfunction in participants with a history of dengue infection. Further larger studies are warranted to validate the findings of this study.

Excess all-cause mortality in the USA and Europe during the COVID-19 pandemic, 2020 and 2021

Both the USA and Europe experienced substantial excess mortality in 2020 and 2021 related to the COVID-19 pandemic. Methods used to estimate excess mortality vary, making comparisons difficult. This retrospective observational study included data on deaths from all causes occurring in the USA and 25 European countries or subnational areas participating in the network for European monitoring of excess mortality for public health action (EuroMOMO). We applied the EuroMOMO algorithm to estimate excess all-cause mortality in the USA and Europe during the first two years of the COVID-19 pandemic, 2020-2021, and compared excess mortality by age group and time periods reflecting three primary waves. During 2020-2021, the USA experienced 154.5 (95% Uncertainty Interval [UI]: 154.2-154.9) cumulative age-standardized excess all-cause deaths per 100,000 person years, compared with 110.4 (95% UI: 109.9-111.0) for the European countries. Excess all-cause mortality in the USA was higher than in Europe for nearly all age groups, with an additional 44.1 excess deaths per 100,000 person years overall from 2020-2021. If the USA had experienced an excess mortality rate similar to Europe, there would have been approximately 391 thousand (36%) fewer excess deaths in the USA.

A late sharp increase in influenza detections and low interim vaccine effectiveness against the circulating A(H3N2) strain, Denmark, 2021/22 influenza season up to 25 March 2022

We estimated interim influenza A vaccine effectiveness (VE) following a late sharp rise in cases during an influenza A(H3N2)-dominated 2021/22 season, after lifting COVID-19 restrictions. In children aged 2–6 years offered a live attenuated influenza vaccine, adjusted VE was 62.7% (95% CI: 10.9–84.4) in hospitalised and 64.2% (95% CI: 50.5–74.1) in non-hospitalised children. In non-hospitalised patients aged 7–44 years, VE was 24.8% (95% CI: 12.8–35.2); VE was non-significant in remaining age groups and hospital/non-hospital settings.

Prevalence and Dynamic Changes in Lung Ultrasound Findings among Adults with Uncomplicated Malaria and Controls in the Amazon Basin, Brazil

Malaria patients are at risk of cardiopulmonary complications but diagnosis and management can be difficult in resource-limited settings. B-lines on lung ultrasound (LUS) mark changes in lung density; however, little is known about their role in malaria. We aimed to examine the prevalence of B-lines in adults with malaria at baseline and follow-up compared with controls in the Amazon Basin. We also examined the relationship between B-lines and left ventricular ejection fraction. We performed eight-zone LUS, echocardiography, and blood smears in 94 adults (mean age 40 years, 54% men) with uncomplicated malaria and 449 controls without heart failure, renal insufficiency or lung disease (mean age 41 years, 38% men). Examinations of adults with malaria were repeated after antimalarial treatment, corresponding to a median of 30 days (interquartile range [IQR] 27-39). Adults with malaria suffered from Plasmodium vivax (N = 70, median 2,823 [IQR 598-7,698] parasites/μL) or P. falciparum (N = 24, median 1,148 [IQR 480-3,128] parasites/μL). At baseline, adults with malaria more frequently had ≥ 3 B-lines (summed across eight zones) compared with controls (30% versus 2%, P value < 0.001), indicating higher lung density. When examinations were repeated, only 6% of adults with malaria had ≥ 3 B-lines at follow-up, which was significant lower compared with baseline (median reduction 3 B-line; P value < 0.001). B-lines were not significantly associated with left ventricular ejection fraction in adults with malaria. In conclusion, B-lines detected by LUS were more frequent in adults with uncomplicated malaria compared with controls and decreased after completed antimalarial treatment.

All-cause versus cause-specific excess deaths for estimating influenza-associated mortality in Denmark, Spain, and the United States

BACKGROUND

Seasonal influenza-associated excess mortality estimates can be timely and provide useful information on the severity of an epidemic. This methodology can be leveraged during an emergency response or pandemic.

METHOD

For Denmark, Spain, and the United States, we estimated age-stratified excess mortality for (i) all-cause, (ii) respiratory and circulatory, (iii) circulatory, (iv) respiratory, and (v) pneumonia, and influenza causes of death for the 2015/2016 and 2016/2017 influenza seasons. We quantified differences between the countries and seasonal excess mortality estimates and the death categories. We used a time-series linear regression model accounting for time and seasonal trends using mortality data from 2010 through 2017.

RESULTS

The respective periods of weekly excess mortality for all-cause and cause-specific deaths were similar in their chronological patterns. Seasonal all-cause excess mortality rates for the 2015/2016 and 2016/2017 influenza seasons were 4.7 (3.3-6.1) and 14.3 (13.0-15.6) per 100,000 population, for the United States; 20.3 (15.8-25.0) and 24.0 (19.3-28.7) per 100,000 population for Denmark; and 22.9 (18.9-26.9) and 52.9 (49.1-56.8) per 100,000 population for Spain. Seasonal respiratory and circulatory excess mortality estimates were two to three times lower than the all-cause estimates.

DISCUSSION

We observed fewer influenza-associated deaths when we examined cause-specific death categories compared with all-cause deaths and observed the same trends in peaks in deaths with all death causes. Because all-cause deaths are more available, these models can be used to monitor virus activity in near real time. This approach may contribute to the development of timely mortality monitoring systems during public health emergencies.

Frequency of Electrocardiographic Alterations and Pericardial Effusion in Patients With Uncomplicated Malaria

Studies have proposed that malaria may lead to electrocardiographic (ECG) changes and pericardial inflammation. We aimed to investigate the frequency of ECG alterations, determined by ECG and Holter monitoring, and pericardial effusion in patients with malaria infection. We performed a prospective observational study of adult patients with uncomplicated malaria in Amazonas, Brazil. Peripheral blood smears, ECG, and bedside echocardiography were conducted before antimalarial treatment and repeated at follow-up after completed treatment. We evaluated the diagnostic value of PR-segment depression, PR-segment elevation, and Spodick's sign for detecting pericardial effusion. A subset of patients underwent Holter monitoring at baseline. Among 98 cases of uncomplicated malaria (55% men; mean age 40 years; median parasite density 1,774/µl), 75 had Plasmodium vivax, 22 Plasmodium falciparum, and 1 had mixed infection. At baseline, 17% (n = 17) had PR-segment depression, 12% (n = 12) PR-segment elevation, 3% (n = 2) Spodick's sign, and the prevalence of pericardial effusion was 9% (n = 9). ECG alterations had sensitivities of 22% to 89% and specificities of 88% to 100% for detecting pericardial effusion at baseline. PR-segment depression had the best accuracy (sensitivity 89%, specificity 90%). Of the 25 patients, 4 patients who did not have pericardial effusion, displayed nonsustained ventricular tachycardia, determined by Holter monitoring (median duration 43 hours). Follow-up examination data were obtained for 71 patients (median 31 days), for whom PR-segment depression, elevation, and pericardial effusion had reduced significantly (p <0.05). In conclusion, our findings suggest that ECG alterations may be useful to detect pericardial effusion in malaria and that these findings decrease after completed antimalarial treatment.

Reassortant Influenza A(H1N1)pdm09 Virus in Elderly Woman, Denmark, January 2021

A case of human infection with influenza A(H1N1)pdm09 virus containing a nonstructural gene highly similar to Eurasian avian-like H1Nx swine influenza virus was detected in Denmark in January 2021. We describe the clinical case and report testing results of the genetic and antigenic characterizations of the virus.

Sex-differences in COVID-19 associated excess mortality is not exceptional for the COVID-19 pandemic

Europe experienced excess mortality from February through June, 2020 due to the COVID-19 pandemic, with more COVID-19-associated deaths in males compared to females. However, a difference in excess mortality among females compared to among males may be a more general phenomenon, and should be investigated in none-COVID-19 situations as well. Based on death counts from Eurostat, separate excess mortalities were estimated for each of the sexes using the EuroMOMO model. Sex-differential excess mortality were expressed as differences in excess mortality incidence rates between the sexes. A general relation between sex-differential and overall excess mortality both during the COVID-19 pandemic and in preceding seasons were investigated. Data from 27 European countries were included, covering the seasons 2016/17 to 2019/20. In periods with increased excess mortality, excess was consistently highest among males. From February through May 2020 male excess mortality was 52.7 (95% PI: 56.29; 49.05) deaths per 100,000 person years higher than for females. Increased male excess mortality compared to female was also observed in the seasons 2016/17 to 2018/19. We found a linear relation between sex-differences in excess mortality and overall excess mortality, i.e., 40 additional deaths among males per 100 excess deaths per 100,000 population. This corresponds to an overall female/male mortality incidence ratio of 0.7. In situations with overall excess mortality, excess mortality increases more for males than females. We suggest that the sex-differences observed during the COVID-19 pandemic reflects a general sex-disparity in excess mortality.

Heart failure associated with imported malaria: a nationwide Danish cohort study

AIMS

Despite adequate treatment, recent studies have hypothesized that malaria may affect long-term cardiovascular function. We aimed to investigate the long-term risk of cardiovascular events and death in individuals with a history of imported malaria in Denmark.

METHODS

Using nationwide Danish registries, we followed individuals with a history of malaria for the risk of incident heart failure (HF), myocardial infarction (MI), cardiovascular death and all-cause death (1 January 1994 to 1 January 2017). The population was age- and sex-matched with individuals without a history of malaria from the Danish population (ratio 1:9). We excluded patients with known HF and ischaemic heart disease at inclusion.

RESULTS

We identified 3912 cases with a history of malaria (mean age 33 ± 17 years, 57% male, 41% Plasmodium falciparum infections). The median follow-up was 9.8 years (interquartile range 3.9-16.4 years). Event rates per 1000 person-years for individuals with a history vs. no history of malaria were HF: 1.84 vs. 1.32; MI: 1.28 vs. 1.30; cardiovascular death: 1.40 vs. 1.77; and all-cause death: 5.04 vs. 5.28. In Cox proportional hazards models adjusted for cardiovascular risk factors, concomitant pharmacotherapy, region of origin, household income and educational level, malaria was associated with HF (HR: 1.59 [1.21-2.09], P = 0.001), but not MI (HR: 1.00 [0.72-1.39], P = 1.00), cardiovascular death (HR: 1.00 [0.74-1.35], P = 0.98) or all-cause death (HR 1.11 [0.94-1.30], P = 0.21). Specifically, P. falciparum infection was associated with increased risk of HF (HR: 1.64 [1.14-2.36], P = 0.008).

CONCLUSION

Individuals with a history of imported malaria, specifically P. falciparum, may have an increased risk of incident HF.

Cardiopulmonary alterations by ultrasound in a patient with uncomplicated mixed malaria infection: a case report from the Amazon Basin

BACKGROUND

Information on cardiopulmonary complications in clinical malaria is sparse and diagnosis may be difficult in resource-limited areas due to lack of proper diagnostic tools and access to medical care. A case of pericardial effusion and pulmonary alterations assessed by ultrasound in a patient with uncomplicated mixed malaria infection is described.

CASE PRESENTATION

A previously healthy 23-year-old male from the Amazon Basin was diagnosed with mixed infection of Plasmodium vivax and Plasmodium falciparum by peripheral blood smear. The patient presented with mild malaria symptoms without signs of severe malaria, but reported moderate chest pain and shortness of breath. Laboratory analyses revealed thrombocytopenia and anemia. The electrocardiogram had PR depressions and bedside ultrasound of the cardiopulmonary system showed pericardial effusion (18 mm) accompanied by multiple B-lines in the lungs, identified as vertical artifacts extending from the pleural line. Cardiac biomarkers were normal. The patient was treated according to national guidelines for malaria and suspected pericarditis, respectively. At follow-up on day 5, the pericardial effusion (9mm) and B-lines had markedly decreased. By day 21 the patient was asymptomatic, had completed the treatment, and the electrocardiogram and ultrasound findings had normalized.

CONCLUSIONS

This case report highlight the usefulness of bedside ultrasound to identify cardiopulmonary involvement in patients with uncomplicated malaria and relevant symptoms.

Abrupt termination of the 2019/20 influenza season following preventive measures against COVID-19 in Denmark, Norway and Sweden

Background

In mid-March 2020, a range of public health and social measures (PHSM) against the then new coronavirus disease (COVID-19) were implemented in Denmark, Norway and Sweden.

Aim

We analysed the development of influenza cases during the implementation of PHSM against SARS-CoV-2 in the Scandinavian countries.

Method

Based on the established national laboratory surveillance of influenza, we compared the number of human influenza cases in the weeks immediately before and after the implementation of SARS-CoV-2 PHSM by country. The 2019/20 influenza season was compared with the five previous seasons.

Results

A dramatic reduction in influenza cases was seen in all three countries, with only a 3- to 6-week duration from the peak of weekly influenza cases until the percentage dropped below 1%. In contrast, in the previous nine influenza seasons, the decline from the seasonal peak to below 1% of influenza-positive samples took more than 10 weeks.

Conclusions

The PHSM against SARS-CoV-2 were followed by a dramatic reduction in influenza cases, indicating a wider public health effect of the implemented measures.

Prevalence of Cardiovascular Complications in Malaria: A Systematic Review and Meta-Analysis

Recent studies have suggested that malaria may affect the cardiovascular system. The aim of this systematic review and meta-analysis was to determine the prevalence of cardiovascular complications in symptomatic malaria patients. We searched databases such as Pubmed, Embase, Cochrane, and Web of Science (January 1950-April 2020) for studies reporting on cardiovascular complications in adults and children with malaria. Cardiovascular complications were defined as abnormalities in electrocardiogram (ECG), cardiac biomarkers, and echocardiography on admission or during outpatient examination. Studies of patients with known heart disease or cardiovascular evaluation performed after the start of intravenous antimalarial medication were excluded. The study was registered in International Prospective Register of Systematic Reviews (PROSPERO) (No.: CRD42020167672). The literature search yielded 1,243 studies, and a total of 43 studies with symptomatic malaria patients were included. Clinical studies (n = 12 adults; n = 5 children) comprised 3,117 patients, of which a majority had Plasmodium falciparum (n = 15) and were diagnosed with severe malaria (n = 13). In random-effects models of adults, the pooled prevalence estimate for any cardiovascular complication was 7% (95% CI: 5-9). No meta-analysis was conducted in children, but the range of abnormal ECG was 0-8%, cardiac biomarkers 0-57%, and echocardiography 4-9%. We analyzed 33 cases (n = 10 postmortem), in which the most common cardiovascular pathologies were myocarditis and acute coronary syndrome. All histopathological studies found evidence of parasitized red blood cells in the myocardium. Cardiovascular complications are not uncommon in symptomatic adults and children with malaria. Additional studies investigating malaria and cardiovascular disease are encouraged.

Estimates of mortality attributable to COVID-19: a statistical model for monitoring COVID-19 and seasonal influenza, Denmark, spring 2020

BackgroundTimely monitoring of COVID-19 impact on mortality is critical for rapid risk assessment and public health action.AimBuilding upon well-established models to estimate influenza-related mortality, we propose a new statistical Attributable Mortality Model (AttMOMO), which estimates mortality attributable to one or more pathogens simultaneously (e.g. SARS-CoV-2 and seasonal influenza viruses), while adjusting for seasonality and excess temperatures.MethodsData from Nationwide Danish registers from 2014-week(W)W27 to 2020-W22 were used to exemplify utilities of the model, and to estimate COVID-19 and influenza attributable mortality from 2019-W40 to 2020-W20.ResultsSARS-CoV-2 was registered in Denmark from 2020-W09. Mortality attributable to COVID-19 in Denmark increased steeply, and peaked in 2020-W14. As preventive measures and national lockdown were implemented from 2020-W12, the attributable mortality started declining within a few weeks. Mortality attributable to COVID-19 from 2020-W09 to 2020-W20 was estimated to 16.2 (95% confidence interval (CI): 12.0 to 20.4) per 100,000 person-years. The 2019/20 influenza season was mild with few deaths attributable to influenza, 3.2 (95% CI: 1.1 to 5.4) per 100,000 person-years.ConclusionAttMOMO estimates mortality attributable to several pathogens simultaneously, providing a fuller picture of mortality by COVID-19 during the pandemic in the context of other seasonal diseases and mortality patterns. Using Danish data, we show that the model accurately estimates mortality attributable to COVID-19 and influenza, respectively. We propose using standardised indicators for pathogen circulation in the population, to make estimates comparable between countries and applicable for timely monitoring.

Real-time monitoring shows substantial excess all-cause mortality during second wave of COVID-19 in Europe, October to December 2020

The European monitoring of excess mortality for public health action (EuroMOMO) network monitors weekly excess all-cause mortality in 27 European countries or subnational areas. During the first wave of the coronavirus disease (COVID-19) pandemic in Europe in spring 2020, several countries experienced extraordinarily high levels of excess mortality. Europe is currently seeing another upsurge in COVID-19 cases, and EuroMOMO is again witnessing a substantial excess all-cause mortality attributable to COVID-19.

Excess all-cause mortality during the COVID-19 pandemic in Europe - preliminary pooled estimates from the EuroMOMO network, March to April 2020

A remarkable excess mortality has coincided with the COVID-19 pandemic in Europe. We present preliminary pooled estimates of all-cause mortality for 24 European countries/federal states participating in the European monitoring of excess mortality for public health action (EuroMOMO) network, for the period March–April 2020. Excess mortality particularly affected  ≥ 65 year olds (91% of all excess deaths), but also 45–64 (8%) and 15–44 year olds (1%). No excess mortality was observed in 0–14 year olds.

Plasmodium cynomolgi as Cause of Malaria in Tourist to Southeast Asia, 2018

We report human infection with simian Plasmodium cynomolgi in a tourist from Denmark who had visited forested areas in peninsular Malaysia and Thailand in August and September 2018. Because P. cynomolgi may go unnoticed by standard malaria diagnostics, this malaria species may be more common in humans than was previously thought.

Pacific Island Pharmacovigilance: The Need for a Different Approach

Many Pacific Island countries (PICs) are recipients of funding support from the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund). However, most of these countries cannot be expected to meet Global Fund and World Health Organization (WHO) minimum requirements for a functioning pharmacovigilance (PV) system. We argue that a different approach is required to move PV forward in such countries. Although the long-term aim is to build adequate national PV capacity, we propose an approach in which resources are focused initially towards ensuring a proper system for the reporting of "problems with medicines" such as substandard and counterfeit products. The limited health system resources in these countries require that PV will be supported by some of the organizations also giving funding aid for the supply of medicines.

Excess all-cause and influenza-attributable mortality in Europe, December 2016 to February 2017

Since December 2016, excess all-cause mortality was observed in many European countries, especially among people aged ≥ 65 years. We estimated all-cause and influenza-attributable mortality in 19 European countries/regions. Excess mortality was primarily explained by circulation of influenza virus A(H3N2). Cold weather snaps contributed in some countries. The pattern was similar to the last major influenza A(H3N2) season in 2014/15 in Europe, although starting earlier in line with the early influenza season start.

The Impact of Introducing Malaria Rapid Diagnostic Tests on Fever Case Management: A Synthesis of Ten Studies from the ACT Consortium

Since 2010, the World Health Organization has been recommending that all suspected cases of malaria be confirmed with parasite-based diagnosis before treatment. These guidelines represent a paradigm shift away from presumptive antimalarial treatment of fever. Malaria rapid diagnostic tests (mRDTs) are central to implementing this policy, intended to target artemisinin-based combination therapies (ACT) to patients with confirmed malaria and to improve management of patients with nonmalarial fevers. The ACT Consortium conducted ten linked studies, eight in sub-Saharan Africa and two in Afghanistan, to evaluate the impact of mRDT introduction on case management across settings that vary in malaria endemicity and healthcare provider type. This synthesis includes 562,368 outpatient encounters (study size range 2,400-432,513). mRDTs were associated with significantly lower ACT prescription (range 8-69% versus 20-100%). Prescribing did not always adhere to malaria test results; in several settings, ACTs were prescribed to more than 30% of test-negative patients or to fewer than 80% of test-positive patients. Either an antimalarial or an antibiotic was prescribed for more than 75% of patients across most settings; lower antimalarial prescription for malaria test-negative patients was partly offset by higher antibiotic prescription. Symptomatic management with antipyretics alone was prescribed for fewer than 25% of patients across all scenarios. In community health worker and private retailer settings, mRDTs increased referral of patients to other providers. This synthesis provides an overview of shifts in case management that may be expected with mRDT introduction and highlights areas of focus to improve design and implementation of future case management programs.

[Climate change, floods and health intervention]

Climate change and variability are considered some of the biggest threats to human health in the 21st century. Extreme weather events such as floods and storms are examples of natural hazards resulting in highest number of disasters and with considerable mortality and morbidity among vulnerable communities. A coordinated, well-planned management of health interventions must be taken for timely action in the response, recovery, prevention and preparedness phases of disasters. Roles and responsibilities of international as well as national organizations and authorities are discussed.

Impact of introduction of rapid diagnostic tests for malaria on antibiotic prescribing: analysis of observational and randomised studies in public and private healthcare settings

Objectives To examine the impact of use of rapid diagnostic tests for malaria on prescribing of antimicrobials, specifically antibiotics, for acute febrile illness in Africa and Asia.Design Analysisof nine preselected linked and codesigned observational and randomised studies (eight cluster or individually randomised trials and one observational study).Setting Public and private healthcare settings, 2007-13, in Afghanistan, Cameroon, Ghana, Nigeria, Tanzania, and Uganda.Participants 522 480 children and adults with acute febrile illness.Interventions Rapid diagnostic tests for malaria.Main outcome measures Proportions of patients for whom an antibiotic was prescribed in trial groups who had undergone rapid diagnostic testing compared with controls and in patients with negative test results compared with patients with positive results. A secondary aim compared classes of antibiotics prescribed in different settings.Results Antibiotics were prescribed to 127 052/238 797 (53%) patients in control groups and 167 714/283 683 (59%) patients in intervention groups. Antibiotics were prescribed to 40% (35 505/89 719) of patients with a positive test result for malaria and to 69% (39 400/57 080) of those with a negative result. All but one study showed a trend toward more antibiotic prescribing in groups who underwent rapid diagnostic tests. Random effects meta-analysis of the trials showed that the overall risk of antibiotic prescription was 21% higher (95% confidence interval 7% to 36%) in intervention settings. In most intervention settings, patients with negative test results received more antibiotic prescriptions than patients with positive results for all the most commonly used classes: penicillins, trimethoprim-sulfamethoxazole (one exception), tetracyclines, and metronidazole.Conclusions Introduction of rapid diagnostic tests for malaria to reduce unnecessary use of antimalarials-a beneficial public health outcome-could drive up untargeted use of antibiotics. That 69% of patients were prescribed antibiotics when test results were negative probably represents overprescription.This included antibiotics from several classes, including those like metronidazole that are seldom appropriate for febrile illness, across varied clinical, health system, and epidemiological settings. It is often assumed that better disease specific diagnostics will reduce antimicrobial overuse, but they might simply shift it from one antimicrobial class to another. Current global implementation of malaria testing might increase untargeted antibiotic use and must be examined.

Improving prescribing practices with rapid diagnostic tests (RDTs): synthesis of 10 studies to explore reasons for variation in malaria RDT uptake and adherence

OBJECTIVES

The overuse of antimalarial drugs is widespread. Effective methods to improve prescribing practice remain unclear. We evaluated the impact of 10 interventions that introduced rapid diagnostic tests for malaria (mRDTs) on the use of tests and adherence to results in different contexts.

DESIGN

A comparative case study approach, analysing variation in outcomes across different settings.

SETTING

Studies from the ACT Consortium evaluating mRDTs with a range of supporting interventions in 6 malaria endemic countries. Providers were governmental or non-governmental healthcare workers, private retail sector workers or community volunteers. Each study arm in a distinct setting was considered a case.

PARTICIPANTS

28 cases from 10 studies were included, representing 148 461 patients seeking care for suspected malaria.

INTERVENTIONS

The interventions included different mRDT training packages, supervision, supplies and community sensitisation.

OUTCOME MEASURES

Analysis explored variation in: (1) uptake of mRDTs (% febrile patients tested); (2) provider adherence to positive mRDTs (% Plasmodium falciparum positive prescribed/given Artemisinin Combination Treatment); (3) provider adherence to negative mRDTs (% P. falciparum negative not prescribed/given antimalarial).

RESULTS

Outcomes varied widely across cases: 12-100% mRDT uptake; 44-98% adherence to positive mRDTs; 27-100% adherence to negative mRDTs. Providers appeared more motivated to perform well when mRDTs and intervention characteristics fitted with their own priorities. Goodness of fit of mRDTs with existing consultation and diagnostic practices appeared crucial to maximising the impact of mRDTs on care, as did prior familiarity with malaria testing; adequate human resources and supplies; possible alternative treatments for mRDT-negative patients; a more directive intervention approach and local preferences for ACTs.

CONCLUSIONS

Basic training and resources are essential but insufficient to maximise the potential of mRDTs in many contexts. Programme design should respond to assessments of provider priorities, expectations and capacities. As mRDTs become established, the intensity of supporting interventions required seems likely to reduce.

The Utility of Malaria Rapid Diagnostic Tests as a Tool in Enhanced Surveillance for Malaria Elimination in Vanuatu

BACKGROUND

As part of efforts to eliminate malaria, Vanuatu has piloted the implementation of enhanced malaria surveillance and response strategies since 2011. This involves passive case detection (PCD) in health facilities, proactive case detection (Pro-ACD) and reactive case detection (Re-ACD) in communities using malaria rapid diagnostic tests (RDTs). While RDTs improve case management, their utility for detection of malaria infections in ACDs in this setting is unclear.

METHODS

The utility of malaria RDTs as diagnostic tools was evaluated in PCD, in five rounds of Pro-ACDs and five rounds of Re-ACDs conducted in Tafea and Torba Provinces between 2011 and 2014. The number of malaria infections detected by RDTs was compared to that detected by PCR from collected used-RDTs.

RESULTS

PCD in Tafea Province (2013) showed a RDT-positive rate of 0.21% (2/939) and a PCR-positive rate of 0.44% (2/453), indicating less than 1% of suspected malaria cases in Tafea Province were due to malaria. In Pro-ACDs conducted in Tafea and Torba Provinces, RDT-positive rates in 2013 and 2014 were 0.14% (3/2145) and 0% (0/2823), respectively, while the corresponding PCR-positive rates were 0.72% (9/1242) and 0.79% (9/1141). PCR identified villages in both provinces appearing to be transmission foci with a small number of low-density infections, mainly P. falciparum infections. In five rounds of Re-ACD, RDTs did not identify any additional infections while PCR detected only one among 173 subjects screened.

CONCLUSIONS

PCD and Pro-ACDs demonstrate that both Tafea and Torba Provinces in Vanuatu has achieved very low malaria prevalence. In these low-transmission areas, conducting Pro-ACD and Re-ACDs using RDTs appears not cost-effective and may have limited impact on interrupting malaria transmission due to the small number of infections identified by RDTs and considerable operational resources invested. More sensitive, field deployable and affordable diagnostic tools will improve malaria surveillance in malaria elimination settings.

Performance of Interferon-Gamma and IP-10 Release Assays for Diagnosing Latent Tuberculosis Infections in Patients with Concurrent Malaria in Tanzania

Interferon-gamma (IFN-γ) release assays (IGRAs) are used to detect cellular immune recognition of Mycobacterium tuberculosis The chemokine IFN-γ-inducible protein 10 (IP-10) is an alternative diagnostic biomarker to IFN-γ. Several conditions interfere with IGRA test performance. We aimed to assess the possible influence of Plasmodium falciparum infection on the IGRA test QuantiFERON-TB GOLD® In-Tube (QFT) test and an in-house IP-10 release assay. In total, 241 Tanzanian adults were included; 184 patients with uncomplicated malaria (88 human immunodeficiency virus [HIV] coinfected) and 57 HIV-infected patients without malaria infection. Malaria was treated with artemether-lumefantrine (Coartem®). QFT testing was performed before initiation of malaria treatment and at days 7 and 42. In total, 172 patients completed follow-up. IFN-γ and IP-10 was measured in QFT supernatants. We found that during malaria infection IFN-γ and IP-10 levels in the unstimulated samples were elevated, mitogen responsiveness was impaired, and CD4 cell counts were decreased. These alterations reverted after malaria treatment. Concurrent malaria infection did not affect QFT test results, whereas there were more indeterminate IP-10 results during acute malaria infection. We suggest that IGRA and IP-10 release assay results of malaria patients should be interpreted with caution and that testing preferably should be postponed until after malaria treatment.

Challenges and key research questions for yaws eradication

Yaws is endemic in west Africa, southeast Asia, and the Pacific region. To eradicate yaws by 2020, WHO has launched a campaign of mass treatment with azithromycin. Progress has been made towards achievement of this ambitious goal, including the validation of point-of-care and molecular diagnostic tests and piloting of the strategy in several countries, including Ghana, Vanuatu, and Papua New Guinea. Gaps in knowledge need to be addressed to allow refinement of the eradication strategy. Studies exploring determinants of the spatial distribution of yaws are needed to help with the completion of baseline mapping. The finding that Haemophilus ducreyi causes lesions similar to yaws is particularly important and further work is needed to assess the effect of azithromycin on these lesions. The integration of diagnostic tests into different stages of the eradication campaign needs investigation. Finally, studies must be done to inform the optimum mass-treatment strategy for sustainable interruption of transmission.

"Every drug goes to treat its own disease…" - a qualitative study of perceptions and experiences of taking anti-retrovirals concomitantly with anti-malarials among those affected by HIV and malaria in Tanzania

Background

Little is known about how people living with human immunodeficiency virus (HIV) experience malaria and the concomitant use of anti-malarial treatments with anti-retrovirals (ARVs). An understanding of how patients make sense of these experiences is important to consider in planning and supporting the clinical management and treatment for co-infected individuals.

Methods

A qualitative study was conducted in Tanzania alongside a clinical trial of concomitant treatment for HIV and malaria co-infection. Focus group discussions were held with people receiving treatment for HIV and/or malaria, and in-depth interviews with health workers responsible for HIV care and members of the clinical trial team. Data were analysed inductively to identify themes and develop theoretical narratives.

Results

Results suggest that people living with HIV perceived malaria to be more harmful to them due to their compromised immune status but saw the disease as unavoidable. For those enrolled in the clinical controlled study, taking anti-malarials together with ARVs was largely seen as unproblematic, with health workers’ advice and endorsement of concomitant drug taking influential in reported adherence. However, perceptions of drug strength appeared to compel some people not enrolled in the clinical study to take the drugs at separate times to avoid anticipated harm to the body.

Conclusions

Management of HIV and malaria concurrently often requires individuals to cross the domains of different disease programmes. In the context of a trial concerned with both diseases, patients experienced the support of clinicians in guiding and reassuring them about when and how to take drugs concomitantly. This points towards the need to continue to strive for integrated care for patients with HIV.

Molecular differentiation of Treponema pallidum subspecies in skin ulceration clinically suspected as yaws in Vanuatu using real-time multiplex PCR and serological methods

We developed a TaqMan-based real-time quadriplex polymerase chain reaction (PCR) to simultaneously detect Treponema pallidum subspecies pallidum, T. pallidum subsp. pertenue, and T. pallidum subsp. endemicum, the causative agents of venereal syphilis, yaws, and bejel, respectively. The PCR assay was applied to samples from skin ulcerations of clinically presumptive yaws cases among children on Tanna Island, Vanuatu. Another real-time triplex PCR was used to screen for the point mutations in the 23S rRNA genes that have previously been associated with azithromycin resistance in T. pallidum subsp. pallidum strains. Seropositivity by the classical syphilis serological tests was 35.5% among children with skin ulcerations clinically suspected with yaws, whereas the presence of T. pallidum subsp. pertenue DNA was only found in lesions from 15.5% of children. No evidence of T. pallidum subsp. pertenue infection, by either PCR or serology was found in ∼59% of cases indicating alternative causes of yaws-like lesions in this endemic area.

The practice of 'doing' evaluation: lessons learned from nine complex intervention trials in action

Background

There is increasing recognition among trialists of the challenges in understanding how particular ‘real-life’ contexts influence the delivery and receipt of complex health interventions. Evaluations of interventions to change health worker and/or patient behaviours in health service settings exemplify these challenges. When interpreting evaluation data, deviation from intended intervention implementation is accounted for through process evaluations of fidelity, reach, and intensity. However, no such systematic approach has been proposed to account for the way evaluation activities may deviate in practice from assumptions made when data are interpreted.

Methods

A collective case study was conducted to explore experiences of undertaking evaluation activities in the real-life contexts of nine complex intervention trials seeking to improve appropriate diagnosis and treatment of malaria in varied health service settings. Multiple sources of data were used, including in-depth interviews with investigators, participant-observation of studies, and rounds of discussion and reflection.

Results and discussion

From our experiences of the realities of conducting these evaluations, we identified six key ‘lessons learned’ about ways to become aware of and manage aspects of the fabric of trials involving the interface of researchers, fieldworkers, participants and data collection tools that may affect the intended production of data and interpretation of findings. These lessons included: foster a shared understanding across the study team of how individual practices contribute to the study goals; promote and facilitate within-team communications for ongoing reflection on the progress of the evaluation; establish processes for ongoing collaboration and dialogue between sub-study teams; the importance of a field research coordinator bridging everyday project management with scientific oversight; collect and review reflective field notes on the progress of the evaluation to aid interpretation of outcomes; and these approaches should help the identification of and reflection on possible overlaps between the evaluation and intervention.

Conclusion

The lessons we have drawn point to the principle of reflexivity that, we argue, needs to become part of standard practice in the conduct of evaluations of complex interventions to promote more meaningful interpretations of the effects of an intervention and to better inform future implementation and decision-making.

How experiences become data: the process of eliciting adverse event, medical history and concomitant medication reports in antimalarial and antiretroviral interaction trials

Background

Accurately characterizing a drug’s safety profile is essential. Trial harm and tolerability assessments rely, in part, on participants’ reports of medical histories, adverse events (AEs), and concomitant medications. Optimal methods for questioning participants are unclear, but different methods giving different results can undermine meta-analyses. This study compared methods for eliciting such data and explored reasons for dissimilar participant responses.

Methods

Participants from open-label antimalarial and antiretroviral interaction trials in two distinct sites (South Africa, n = 18 [all HIV positive]; Tanzania, n = 80 [86% HIV positive]) were asked about ill health and treatment use by sequential use of (1) general enquiries without reference to particular conditions, body systems or treatments, (2) checklists of potential health issues and treatments, (3) in-depth interviews. Participants’ experiences of illness and treatment and their reporting behaviour were explored qualitatively, as were trial clinicians’ experiences with obtaining participant reports. Outcomes were the number and nature of data by questioning method, themes from qualitative analyses and a theoretical interpretation of participants’ experiences.

Results

There was an overall cumulative increase in the number of reports from general enquiry through checklists to in-depth interview; in South Africa, an additional 12 medical histories, 21 AEs and 27 medications; in Tanzania an additional 260 medical histories, 1 AE and 11 medications. Checklists and interviews facilitated recognition of health issues and treatments, and consideration of what to report. Information was sometimes not reported because participants forgot, it was considered irrelevant or insignificant, or they feared reporting. Some medicine names were not known and answers to questions were considered inferior to blood tests for detecting ill health. South African inpatient volunteers exhibited a “trial citizenship”, working to achieve researchers’ goals, while Tanzanian outpatients sometimes deferred responsibility for identifying items to report to trial clinicians.

Conclusions

Questioning methods and trial contexts influence the detection of adverse events, medical histories and concomitant medications. There should be further methodological work to investigate these influences and find appropriate questioning methods.

G6PD testing in support of treatment and elimination of malaria: recommendations for evaluation of G6PD tests

Malaria elimination will be possible only with serious attempts to address asymptomatic infection and chronic infection by both Plasmodium falciparum and Plasmodium vivax. Currently available drugs that can completely clear a human of P. vivax (known as "radical cure"), and that can reduce transmission of malaria parasites, are those in the 8-aminoquinoline drug family, such as primaquine. Unfortunately, people with glucose-6-phosphate dehydrogenase (G6PD) deficiency risk having severe adverse reactions if exposed to these drugs at certain doses. G6PD deficiency is the most common human enzyme defect, affecting approximately 400 million people worldwide.Scaling up radical cure regimens will require testing for G6PD deficiency, at two levels: 1) the individual level to ensure safe case management, and 2) the population level to understand the risk in the local population to guide Plasmodium vivax treatment policy. Several technical and operational knowledge gaps must be addressed to expand access to G6PD deficiency testing and to ensure that a patient's G6PD status is known before deciding to administer an 8-aminoquinoline-based drug.In this report from a stakeholder meeting held in Thailand on October 4 and 5, 2012, G6PD testing in support of radical cure is discussed in detail. The focus is on challenges to the development and evaluation of G6PD diagnostic tests, and on challenges related to the operational aspects of implementing G6PD testing in support of radical cure. The report also describes recommendations for evaluation of diagnostic tests for G6PD deficiency in support of radical cure.

Active case detection for malaria elimination: a survey among Asia Pacific countries

Background

Moving from malaria control to elimination requires national malaria control programmes to implement strategies to detect both symptomatic and asymptomatic cases in the community. In order to do this, malaria elimination programmes follow up malaria cases reported by health facilities to carry out case investigations that will determine the origin of the infection, whether it has been imported or is due to local malaria transmission. If necessary, the malaria programme will also carry out active surveillance to find additional malaria cases in the locality to prevent further transmission. To understand current practices and share information on malaria elimination strategies, a survey specifically addressing country policies on case investigation and reactive case detection was carried out among fourteen countries of the Asia Pacific Malaria Elimination Network (APMEN).

Methods

A questionnaire was distributed to the malaria control programme managers amongst 14 countries in the Asia Pacific who have national or sub-national malaria elimination goals.

Results

Results indicate that there are a wide variety of case investigation and active case detection activities employed by the 13 countries that responded to the survey. All respondents report conducting case investigation as part of surveillance activities. More than half of these countries conduct investigations for each case. Over half aim to accomplish the investigation within one to two days of a case report. Programmes collect a broad array of demographic data during investigation procedures and definitions for imported cases are varied across respondents. Some countries report intra-national (from a different province or district) importation while others report only international importation (from a different country). Reactive case detection in respondent countries is defined as screening households within a pre-determined radius in order to identify other locally acquired infections, whether symptomatic or asymptomatic. Respondents report that reactive case detection can be triggered in different ways, in some cases with only a single case report and in others if a defined threshold of multiple cases occurs. The spatial range of screening conducted varies from a certain number of households to an entire administrative unit (e g, village). Some countries target symptomatic people whereas others target all people in order to detect asymptomatic infections. The majority of respondent programmes collect a range of information from those screened for malaria, similar to the range of information collected during case investigation.

Conclusion

Case investigation and reactive case detection are implemented in the malaria elimination programmes in the Asia Pacific, however practices vary widely from country to country. There is little evidence available to support countries in deciding which methods to maintain, change or adopt for improved effectiveness and efficiency. The development and use of common evaluation metrics for these activities will allow malaria programmes to assess performance and results of resource-intensive surveillance measures and may benefit other countries that are considering implementing these activities.

Determinants of malaria program expenditures during elimination: case study evidence from select provinces in the Philippines

...Even though eliminating malaria from the endemic margins is a part of the Global Malaria Action Plan, little guidance exists on what resources are needed to transition from controlling malaria to eliminating it. Using Philippines as an example, this study aimed to (1) estimate the financial resources used by sub-national malaria programs in different phases during elimination and (2) understand how different environmental and organizational factors may influence expenditure levels and spending proportions. The Philippines provides an opportunity to study variations in sub-national programs because its epidemiological and ecological diversity, devolved health system, and progressive elimination strategy all allow greater flexibility for lower-level governments to direct activities, but also create challenges for coordination and resource mobilization. Through key informant interviews and archival record retrieval in four selected provinces chosen based on eco-epidemiological variation, expenditures associated with provincial malaria programs were collected for selected years (mid-1990s to 2010). Results show that expenditures per person at risk per year decrease as programs progress from a state of controlled low-endemic malaria to elimination to prevention of reintroduction regardless of whether elimination was deliberately planned. However, wide variation across provinces were found: expenditures were generally higher if mainly financed with donor grants, but were moderated by the level of economic development, the level of malaria transmission and receptivity, and the capacity of program staff. Across all provinces, strong leadership appears to be a necessary condition for maintaining progress and is vital in controlling outbreaks. While sampled provinces and years may not be representative of other sub-national malaria programs, these findings suggest that the marginal yearly cost declines with each phase during elimination.

‘… in the project they really care for us’: Meaning and experiences of participating in a clinical study of first-line treatment for malaria and HIV in Tanzanian adults

Critiques of biomedical research in low-resource settings typically centre on clinical trials and the ‘dissymmetries of power’ between the researched and those benefiting from the products of research. It is important to extend this critical lens to other forms of global health research. We conducted a qualitative study in Tanzania to explore meaning and experiences of participating in a clinical observational study evaluating the safety and efficacy of current practice for treating HIV and malaria co-infection. Focus group discussions and in-depth interviews were undertaken with 124 study participants, study staff and health workers. Participants' understanding of the study's research aims was limited, but the practice of participation – engaging with research staff and materials – appeared to facilitate interpretations of the study's value, conceptualised as a ‘service’. For those peripheral to the study, however, interpretations of it reflected existing suspicions of experimental research. Our findings indicate the importance of considering the expectations, roles and responsibilities constructed through the practice of participation in different types of research, and how they relate to legacies of research. Understanding how networks of research practice intersect local social and historical contexts can extend discussions of collaboration and engagement with research in low-resource settings.

Review of key knowledge gaps in glucose-6-phosphate dehydrogenase deficiency detection with regard to the safe clinical deployment of 8-aminoquinoline treatment regimens: a workshop report

The diagnosis and management of glucose-6-phosphate dehydrogenase (G6PD) deficiency is a crucial aspect in the current phases of malaria control and elimination, which will require the wider use of 8-aminoquinolines for both reducing Plasmodium falciparum transmission and achieving the radical cure of Plasmodium vivax. 8-aminoquinolines, such as primaquine, can induce severe haemolysis in G6PD-deficient individuals, potentially creating significant morbidity and undermining confidence in 8-aminoquinoline prescription. On the other hand, erring on the side of safety and excluding large numbers of people with unconfirmed G6PD deficiency from treatment with 8-aminoquinolines will diminish the impact of these drugs. Estimating the remaining G6PD enzyme activity is the most direct, accessible, and reliable assessment of the phenotype and remains the gold standard for the diagnosis of patients who could be harmed by the administration of primaquine. Genotyping seems an unambiguous technique, but its use is limited by cost and the large range of recognized G6PD genotypes. A number of enzyme activity assays diagnose G6PD deficiency, but they require a cold chain, specialized equipment, and laboratory skills. These assays are impractical for care delivery where most patients with malaria live. Improvements to the diagnosis of G6PD deficiency are required for the broader and safer use of 8-aminoquinolines to kill hypnozoites, while lower doses of primaquine may be safely used to kill gametocytes without testing. The discussions and conclusions of a workshop conducted in Incheon, Korea in May 2012 to review key knowledge gaps in G6PD deficiency are reported here.

A high-resolution geospatial surveillance-response system for malaria elimination in Solomon Islands and Vanuatu

Background

A high-resolution surveillance-response system has been developed within a geographic information system (GIS) to support malaria elimination in the Pacific. This paper examines the application of a GIS-based spatial decision support system (SDSS) to automatically locate and map the distribution of confirmed malaria cases, rapidly classify active transmission foci, and guide targeted responses in elimination zones.

Methods

Customized SDSS-based surveillance-response systems were developed in the three elimination provinces of Isabel and Temotu, Solomon Islands and Tafea, Vanuatu. Confirmed malaria cases were reported to provincial malaria offices upon diagnosis and updated into the respective SDSS as part of routine operations throughout 2011. Cases were automatically mapped by household within the SDSS using existing geographical reconnaissance (GR) data. GIS queries were integrated into the SDSS-framework to automatically classify and map transmission foci based on the spatiotemporal distribution of cases, highlight current areas of interest (AOI) regions to conduct foci-specific targeted response, and extract supporting household and population data. GIS simulations were run to detect AOIs triggered throughout 2011 in each elimination province and conduct a sensitivity analysis to calculate the proportion of positive cases, households and population highlighted in AOI regions of a varying geographic radius.

Results

A total of 183 confirmed cases were reported and mapped using the SDSS throughout 2011 and used to describe transmission within a target population of 90,354. Automatic AOI regions were also generated within each provincial SDSS identifying geographic areas to conduct response. 82.5% of confirmed cases were automatically geo-referenced and mapped at the household level, with 100% of remaining cases geo-referenced at a village level. Data from the AOI analysis indicated different stages of progress in each province, highlighting operational implications with regards to strategies for implementing surveillance-response in consideration of the spatiotemporal nature of cases as well as logistical and financial constraints of the respective programmes.

Conclusions

Geospatial systems developed to guide Pacific Island malaria elimination demonstrate the application of a high resolution SDSS-based approach to support key elements of surveillance-response including understanding epidemiological variation within target areas, implementing appropriate foci-specific targeted response, and consideration of logistical constraints and costs.

Prevalence of single nucleotide polymorphisms in the Plasmodium falciparum multidrug resistance gene (Pfmdr-1) in Korogwe District in Tanzania before and after introduction of artemisinin-based combination therapy

Tanzania implemented artemether-lumefantrine (AL) as the first-line treatment for uncomplicated malaria in November of 2006 because of resistance to sulfadoxine-pyrimethamine. AL remains highly efficacious, but widespread use may soon facilitate emergence of artemisinin tolerance/resistance, which initially may be detected at the molecular level as temporal changes in the frequency of single nucleotide polymorphisms (SNPs) in the Pfmdr-1 gene associated with AL resistance. In Tanzania, 830 Plasmodium falciparum-positive samples collected between 2003 and 2010 were examined for SNPs of Pfmdr-1 at codons 86, 184, and 1246. Both the N86 and 184F increased from 2006 to 2010 (logistic regression; N86: odds ratio [95% confidence interval] = 1.35 [1.07-1.71], P = 0.01; 184F: odds ratio = 1.42 [1.07-1.88], P = 0.02), and no change was found for D1246 (odds ratio = 1.01 [0.80-1.28], P = 0.9). The observed changes may be because of introduction of AL, and if so, this finding gives cause for concern and argues for continued surveillance of these molecular markers.

A spatial decision support system for guiding focal indoor residual interventions in a malaria elimination zone

A customized geographical information system (GIS) has been developed to support focal indoor residual spraying (IRS) operations as part of a scaled-up campaign to progressively eliminate malaria in Vanuatu. The aims of the GISbased spatial decision support system (SDSS) were to guide the planning, implementation and assessment of IRS at the household level. Additional aims of this study were to evaluate the user acceptability of a SDSS guiding IRS interventions. IRS was conducted on Tanna Island, Republic of Vanuatu between 26 October and 5 December 2009. Geo-referenced household information provided a baseline within the SDSS. An interactive mapping interface was used to delineate operation areas, extract relevant data to support IRS field teams. In addition, it was used as a monitoring tool to assess overall intervention coverage. Surveys and group discussions were conducted during the operations to ascertain user acceptability. Twenty-one operation areas, comprising a total of 187 settlements and 3,422 households were identified and mapped. A total of 3,230 households and 12,156 household structures were sprayed, covering a population of 13,512 individuals, achieving coverage of 94.4% of the households and 95.7% of the population. Village status maps were produced to visualize the distribution of IRS at the sub-village level. One hundred percent of survey respondents declared the SDSS a useful and effective tool to support IRS. The GIS-based SDSS adopted in Tanna empowered programme managers at the provincial level to implement and asses the IRS intervention with the degree of detail required for malaria elimination. Since completion, SDSS applications have expanded to additional provinces in Vanuatu and the neighbouring Solomon Islands supporting not only specific malaria elimination and control interventions, but also the broader public health sector in general.

Using rapid diagnostic tests as source of malaria parasite DNA for molecular analyses in the era of declining malaria prevalence

Background

Malaria prevalence has recently declined markedly in many parts of Tanzania and other sub-Saharan African countries due to scaling-up of control interventions including more efficient treatment regimens (e.g. artemisinin-based combination therapy) and insecticide-treated bed nets. Although continued molecular surveillance of malaria parasites is important to early identify emerging anti-malarial drug resistance, it is becoming increasingly difficult to obtain parasite samples from ongoing studies, such as routine drug efficacy trials. To explore other sources of parasite DNA, this study was conducted to examine if sufficient DNA could be successfully extracted from malaria rapid diagnostic tests (RDTs), used and collected as part of routine case management services in health facilities, and thus forming the basis for molecular analyses, surveillance and quality control (QC) testing of RDTs.

Methods

One hyper-parasitaemic blood sample (131,260 asexual parasites/μl) was serially diluted in triplicates with whole blood and blotted on RDTs. DNA was extracted from the RDT dilution series, either immediately or after storage for one month at room temperature. The extracted DNA was amplified using a nested PCR method for Plasmodium species detection. Additionally, 165 archived RDTs obtained from ongoing malaria studies were analysed to determine the amplification success and test applicability of RDT for QC testing.

Results

DNA was successfully extracted and amplified from the three sets of RDT dilution series and the minimum detection limit of PCR was <1 asexual parasite/μl. DNA was also successfully amplified from (1) 70/71 (98.6%) archived positive RDTs (RDTs and microscopy positive) (2) 52/63 (82.5%) false negative RDTs (negative by RDTs but positive by microscopy) and (3) 4/24 (16.7%) false positive RDTs (positive by RDTs but negative by microscopy). Finally, 7(100%) negative RDTs (negative by RDTs and microscopy) were also negative by PCR.

Conclusion

This study showed that DNA extracted from archived RDTs can be successfully amplified by PCR and used for detection of malaria parasites. Since Tanzania is planning to introduce RDTs in all health facilities (and possibly also at community level), availability of archived RDTs will provide an alternative source of DNA for genetic studies such as continued surveillance of parasite resistance to anti-malarial drugs. The DNA obtained from RDTs can also be used for QC testing by detecting malaria parasites using PCR in places without facilities for microscopy.

Insect cells are superior to Escherichia coli in producing malaria proteins inducing IgG targeting PfEMP1 on infected erythrocytes

BACKGROUND

The PFD1235w Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigen is associated with severe malaria in children and can be expressed on the surface of infected erythrocytes (IE) adhering to ICAM1. However, the exact three-dimensional structure of this PfEMP1 and its surface-exposed epitopes are unknown. An insect cell and Escherichia coli based system was used to express single and double domains encoded by the pfd1235w var gene. The resulting recombinant proteins have been evaluated for yield and purity and their ability to induce rat antibodies, which react with the native PFD1235w PfEMP1 antigen expressed on 3D7PFD1235w-IE. Their recognition by human anti-malaria antibodies from previously infected Tanzanian donors was also analysed.

METHODS

The recombinant proteins were run on SDS-PAGE and Western blots for quantification and size estimation. Insect cell and E. coli-produced recombinant proteins were coupled to a bead-based Luminex assay to measure the plasma antibody reactivity of 180 samples collected from Tanzanian individuals. The recombinant proteins used for immunization of rats and antisera were also tested by flow cytometry for their ability to surface label 3D7PFD1235w-IE.

RESULTS

All seven pAcGP67A constructs were successfully expressed as recombinant protein in baculovirus-infected insect cells and subsequently produced to a purity of 60-97% and a yield of 2-15 mg/L. By comparison, only three of seven pET101/D-TOPO constructs expressed in the E. coli system could be produced at all with purity and yield ranging from 3-95% and 6-11 mg/L. All seven insect cell, but only two of the E. coli produced proteins induced antibodies reactive with native PFD1235w expressed on 3D7PFD1235w-IE. The recombinant proteins were recognized in an age- and transmission intensity-dependent manner by antibodies from 180 Tanzanian individuals in a bead-based Luminex assay.

CONCLUSIONS

The baculovirus based insect cell system was distinctly superior to the E. coli expression system in producing a larger number of different recombinant PFD1235w protein domains and these were significantly easier to purify at a useful yield. However, proteins produced in both systems were able to induce antibodies in rats, which can recognize the native PFD1235w on the surface of IE.

Distinct patterns of blood-stage parasite antigens detected by plasma IgG subclasses from individuals with different level of exposure to Plasmodium falciparum infections

Background

In endemic regions naturally acquired immunity against Plasmodium falciparum develops as a function of age and exposure to parasite infections and is known to be mediated by IgG. The targets of protective antibodies remain to be fully defined. Several immunoepidemiological studies have indicated an association of cytophilic anti-parasite IgG with protection against malaria. It has been hypothesized that the initial antibody responses against parasite antigens upon first few Plasmodium falciparum infections is dominated by non-protective IgG2/IgG4 and IgM antibodies, which then gradually develop into protective response dominated by cytophilic IgG1 and IgG3 antibodies.

Methods

Naturally occurring IgG antibodies against P. falciparum blood-stage antigens were analysed from plasma samples collected from four groups of individuals differing in age and level of exposure to P. falciparum infections. Western Blot profiling of blood-stage parasite antigens displaying reactivity with individual plasma samples in terms of their subclass specificities was conducted. Parasite antigens detected by IgG were grouped based on their apparent molecular sizes resolved by SDS-PAGE as high molecular weight (≥ 70 kDa) or low molecular weight (< 70 kDa). The number of discernable low molecular weight parasite antigens detected by different IgG subclass antibodies from each plasma sample was recorded. Using Wilcoxons rank sum test these reactivities were compared amongst groups of individuals with different levels of exposure to P. falciparum infections.

Results

IgG4 and IgM antibodies in plasma samples from all groups detected very few parasite antigens. IgG2 antibodies from all groups detected a common pattern of high molecular weight parasite antigens. Cytophilic IgG subclasses in plasma samples from individuals with higher levels of exposure to P. falciparum infections distinctly detected higher numbers of low molecular weight parasite antigens.

Conclusions

In the present study, there was no evidence for switching of antibody responses from non-cytophilic to cytophilic subclasses against blood-stage parasite antigens as a likely mechanism for induction of protective immunity against malaria.