Pregnancy and malaria: the perfect storm

Assessment of uptake of sulphadoxine-pyrimethamine for intermittent preventive treatment among pregnant women in Osun State, Nigeria

BACKGROUND

About 32 million pregnant women are at the risk of malaria infection yearly in malaria-endemic sub-Saharan Africa. To mitigate the risks associated with malaria in pregnancy, the WHO recommends ≥3 doses of intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP), covering from the second trimester of pregnancy until delivery.

METHODS

This cross-sectional study assessed the uptake and extent of adherence with IPTp-SP among pregnant women in Osun State, Nigeria, from October 2020 to March 2021. Assessment of the uptake was done by extracting information from the validated case report forms. Venous blood samples were obtained to assess the levels of sulphadoxine in plasma through HPLC-UV.

RESULTS

In total, 49.24%, 38.17% and 12.58% of the study participants obtained 1, 2 and ≥3 doses of IPTp-SP, respectively. In assessing the extent of adherence, 46.67% obtained their last dose within 28 d before sample collection. Uptake of IPTp-SP is not associated with gravidity (p=0.603), but is weakly associated with the age of the study participants (p=0.04). The median (IQR) plasma sulphadoxine concentration was 10.6248 (2.8124-27.1242) ug/mL.

CONCLUSIONS

Utilisation of the intervention is still very low and adherence appears to be inadequate among the study population, suggesting that more advocacy on the IPTp-SP strategy and the implementation of directly observed therapy is necessary.

Placental malaria and adverse pregnancy outcomes in Majang Zone of Gambella Region, Southwest Ethiopia: a histopathological and molecular study

BACKGROUND

Placental malaria (PM) is characterized by Plasmodium parasite sequestration in the placenta. It is responsible for various adverse pregnancy outcomes, including maternal anaemia and low birth weight (LBW). This study aimed to assess prevalence and risk factors of PM, and gestational malaria (GM), together with the prevalence of congenital malaria (CM), maternal anaemia, and LBW among parturient women attending delivery ward of Metti Health Centre (Metti HC) in Majang Zone of Gambella Region, Southwest Ethiopia.

METHODS

A cross-sectional study involving 180 parturient women attending delivery ward of Metti HC was conducted from November 2022-March 2023. Sociodemographic, obstetric, and anti-malarial intervention data were collected. Capillary, placental and cord blood, and placental biopsy were collected to diagnose malaria using rapid diagnostic test (RDT), microscopy, quantitative polymerase chain reaction (qPCR), and histopathology. Haemoglobin concentration and blood group of the mother and weight of the newborn were determined. Statistical analyses were done by SPSS Version 26.0. Multivariable logistic regression analysis and Chi-square test were done to identify risk factors. Results were presented in text, tables and graphs.

RESULTS

The prevalence of GM, PM, CM, maternal anaemia, and LBW was 24.4% (95% CI 18.1-30.1), 34.4% (95% CI 27.4-41.4), 5.0% (95% CI 2.4-8.8), 41.7% (95% CI 34.6-49.0) and 27.8% (95% CI 21.6-34.6), respectively. Risk factors of GM were: presence of malaria history within the previous year (AOR: 5.10; 95% CI 1.64-15.83), lack of indoor residual spray (IRS) within the previous year (AOR: 2.98; 95% CI 1.05-8.45), and lack of antenatal care (ANC) contact during the index pregnancy (AOR: 3.96; 95% CI 1.44-10.87). Risk factors of PM were: presence of malaria history within the previous year (AOR: 2.98; 95% CI 1.05-8.45), and lack of ANC contact during the index pregnancy (AOR: 4.83; 95% CI 1.91-12.18). The risk of CM (p < 0.001), maternal anaemia (p < 0.001) and LBW (p < 0.001) increased with GM and PM.

CONCLUSION

There is high prevalence of GM, PM, maternal anaemia, and LBW in the study area. The presence of GM and PM increased the risk of maternal anaemia, CM, and LBW. The identified risk factors should be considered to mitigate malaria among parturient women and its adverse outcomes.

Chemoprevention of malaria with long-acting oral and injectable drugs: an updated target product profile

Malaria is preventable, but the burden of disease remains high with over 249 million cases and 608,000 deaths reported in 2022. Historically, the most important protective interventions have been vector control and chemopreventive medicines with over 50 million children receiving seasonal malaria chemoprevention in the year 2023. Two vaccines are approved and starting to be deployed, bringing additional protection for children up to 36 months. However, the impact of these currently available tools is somewhat limited on various fronts. Vaccines exhibit partial efficacy, are relatively costly, and not accessible in all settings. The challenges encountered with chemoprevention are barriers to acceptability and feasibility, including frequency of dosing, and the lack of options in the first trimester of pregnancy and for women living with HIV. Also, the emergence of resistance against chemopreventive medicines is concerning. To address these limitations, a target product profile (TPP) is proposed as a road map to guide innovation and to boost the quest for novel chemopreventive alternatives. This TPP describes the ideal product attributes, while acknowledging potential trade-offs that may be needed. Critically, it considers the target populations most at risk; primarily infants, children, and pregnant women. Malaria control and elimination requires appropriate chemoprevention, not only in areas of high endemicity and transmission, but also in lower transmission areas where immunity is declining, as well as for travellers from areas where malaria has been eliminated. New medicines should show acceptable safety and tolerability, with high and long protective efficacy. Formulations and costs need to support operational adherence, access, and effectiveness. Next generation long-acting oral and injectable drugs are likely to constitute the backbone of malaria prevention. Therefore, the perspectives of front-line experts in malaria prevention, researchers, and those involved in drug development are captured in the TPP. This inclusive approach aims at concentrating efforts and aligning responses across the community to develop new and transformative medicines.

The emergence of artemisinin partial resistance in Africa: how do we respond?

Malaria remains one of the most important infectious diseases in the world, with the greatest burden in sub-Saharan Africa, primarily from Plasmodium falciparum infection. The treatment and control of malaria is challenged by resistance to most available drugs, but partial resistance to artemisinins (ART-R), the most important class for the treatment of malaria, was until recently confined to southeast Asia. This situation has changed, with the emergence of ART-R in multiple countries in eastern Africa. ART-R is mediated primarily by single point mutations in the P falciparum kelch13 protein, with several mutations present in African parasites that are now validated resistance mediators based on clinical and laboratory criteria. Major priorities at present are the expansion of genomic surveillance for ART-R mutations across the continent, more frequent testing of the efficacies of artemisinin-based regimens against uncomplicated and severe malaria in trials, more regular assessment of ex-vivo antimalarial drug susceptibilities, consideration of changes in treatment policy to deter the spread of ART-R, and accelerated development of new antimalarial regimens to overcome the impacts of ART-R. The emergence of ART-R in Africa is an urgent concern, and it is essential that we increase efforts to characterise its spread and mitigate its impact.

Impact on pregnancy outcomes of intermittent preventive treatment with sulfadoxine-pyrimethamine in urban and peri-urban Papua New Guinea: a retrospective cohort study

BACKGROUND

Intermittent preventive treatment in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) reduces malaria-attributable adverse pregnancy outcomes and may also prevent low birth weight (< 2,500 g) through mechanisms independent of malaria. Malaria transmission in Papua New Guinea (PNG) is highly heterogeneous. The impact of IPTp-SP on adverse birth outcomes in settings with little or no malaria transmission, such as PNG's capital city Port Moresby, is unknown.

METHODS

A retrospective cohort study was conducted amongst HIV-negative women with a singleton pregnancy who delivered at Port Moresby General Hospital between 18 July and 21 August 2022. The impact of IPTp-SP doses on adverse birth outcomes and anaemia was assessed using logistic and linear regression models, as appropriate.

RESULTS

Of 1,140 eligible women amongst 1,228 consecutive births, 1,110 had a live birth with a documented birth weight. A total of 156 women (13.7%) did not receive any IPTp-SP, 347 women (30.4%) received one, 333 (29.2%) received two, and 304 (26.7%) received the recommended ≥ 3 doses of IPTp-SP. A total of 65 of 1,110 liveborn babies (5.9%) had low birth weight and there were 34 perinatal deaths (3.0%). Anaemia (haemoglobin < 100 g/L) was observed in 30.6% (243/793) of women, and 14 (1.2%) had clinical malaria in pregnancy. Compared to women receiving 0-1 dose of IPTp-SP, women receiving ≥ 2 doses had lower odds of LBW (adjusted odds ratio [aOR] 0.50; 95% confidence interval [CI] 0.26, 0.96), preterm birth (aOR 0.58; 95% CI 0.32, 1.04), perinatal death (aOR 0.49; 95% CI 0.18, 1.38), LBW/perinatal death (aOR 0.55; 95% CI 0.27, 1.12), and anaemia (OR 0.50; 95% CI 0.36, 0.69). Women who received 2 doses versus 0-1 had 45% lower odds of LBW (aOR 0.55, 95% CI 0.27, 1.10), and a 16% further (total 61%) reduction with ≥ 3 doses (aOR 0.39, 95% CI 0.14, 1.05). Birth weights for women who received 2 or ≥ 3 doses versus 0-1 were 81 g (95% CI -3, 166) higher, and 151 g (58, 246) higher, respectively.

CONCLUSIONS

Provision of IPTp-SP in a low malaria-transmission setting in PNG appears to translate into substantial health benefits, in a dose-response manner, supporting the strengthening IPTp-SP uptake across all transmission settings in PNG.

Malaria in pregnancy: Meta-analyses of prevalence and associated complications

This review aims to assess the prevalence of malaria in pregnancy during antenatal visits and delivery, species-specific burden together with regional variation in the burden of disease. It also aims to estimate the proportions of adverse pregnancy outcomes in malaria-positive women. Based on the PRISMA guidelines, a thorough and systematic search was conducted in July 2023 across two electronic databases (including PubMed and CENTRAL). Forest plots were constructed for each outcome of interest highlighting the effect measure, confidence interval, sample size, and its associated weightage. All the statistical meta-analysis were conducted using R-Studio version 2022.07. Sensitivity analyses, publication bias assessment, and meta-regression analyses were also performed to ensure robustness of the review. According to the pooled estimates of 253 studies, the overall prevalence of malaria was 18.95% (95% CI: 16.95-21.11), during antenatal visits was 20.09% (95% CI: 17.43-23.06), and at delivery was 17.32% (95% CI: 14.47-20.61). The highest proportion of malarial infection was observed in Africa approximating 21.50% (95% CI: 18.52-24.81) during ANC and 20.41% (95% CI: 17.04-24.24) at the time of delivery. Our analysis also revealed that the odds of having anaemia were 2.40 times (95% CI: 1.87-3.06), having low birthweight were 1.99 times (95% CI: 1.60-2.48), having preterm birth were 1.65 times (95% CI: 1.29-2.10), and having stillbirths were 1.40 times (95% CI: 1.15-1.71) in pregnant women with malaria.

Malaria

Malaria is resurging in many African and South American countries, exacerbated by COVID-19-related health service disruption. In 2021, there were an estimated 247 million malaria cases and 619 000 deaths in 84 endemic countries. Plasmodium falciparum strains partly resistant to artemisinins are entrenched in the Greater Mekong region and have emerged in Africa, while Anopheles mosquito vectors continue to evolve physiological and behavioural resistance to insecticides. Elimination of Plasmodium vivax malaria is hindered by impractical and potentially toxic antirelapse regimens. Parasitological diagnosis and treatment with oral or parenteral artemisinin-based therapy is the mainstay of patient management. Timely blood transfusion, renal replacement therapy, and restrictive fluid therapy can improve survival in severe malaria. Rigorous use of intermittent preventive treatment in pregnancy and infancy and seasonal chemoprevention, potentially combined with pre-erythrocytic vaccines endorsed by WHO in 2021 and 2023, can substantially reduce malaria morbidity. Improved surveillance, better access to effective treatment, more labour-efficient vector control, continued drug development, targeted mass drug administration, and sustained political commitment are required to achieve targets for malaria reduction by the end of this decade.

The effect and control of malaria in pregnancy and lactating women in the Asia-Pacific region

Half of all pregnancies at risk of malaria worldwide occur in the Asia-Pacific region, where Plasmodium falciparum and Plasmodium vivax co-exist. Despite substantial reductions in transmission, malaria remains an important cause of adverse health outcomes for mothers and offspring, including pre-eclampsia. Malaria transmission is heterogeneous, and infections are commonly subpatent and asymptomatic. High-grade antimalarial resistance poses a formidable challenge to malaria control in pregnancy in the region. Intermittent preventive treatment in pregnancy reduces infection risk in meso-endemic New Guinea, whereas screen-and-treat strategies will require more sensitive point-of-care tests to control malaria in pregnancy. In the first trimester, artemether-lumefantrine is approved, and safety data are accumulating for other artemisinin-based combinations. Safety of novel antimalarials to treat artemisinin-resistant P falciparum during pregnancy, and of 8-aminoquinolines during lactation, needs to be established. A more systematic approach to the prevention of malaria in pregnancy in the Asia-Pacific is required.

Trends of the Global, Regional and National Incidence, Mortality, and Disability-Adjusted Life Years of Malaria, 1990-2019: An Analysis of the Global Burden of Disease Study 2019

Background

Malaria remains a substantial concern in the realm of public health on a worldwide level. Using information from the global burden of disease (GBD) 2019 for 204 countries and territories between 1990 and 2019, we assessed the burden of malaria.

Methods

Data on malaria were derived from the GBD 2019 study between 1990 and 2019. We evaluated the number of incidence, deaths, disability-adjusted life years (DALYs), age-standardized incidence rates (ASIR), age-standardized mortality rates (ASMR), and age-standardized DALY rates (ASDR), examining them across variables such as age, year, gender, country, region, and socio-demographic index (SDI).

Results

The burden of malaria decreased globally between 1990 and 2019. There were 2313.57×10⁵ incident cases and 6.43×10⁵ deaths in 2019, contributing to 464.38×10⁵ DALYs. Largest incident cases were observed in Western Sub-Saharan Africa [1151.72 (95% UI: 890.01-1527.17)] ×10⁵ in 2019. The only region where deaths increased between 1990 and 2019 was Western Sub-Saharan Africa. ASRs of malaria are distributed heterogeneously in different regions. The highest ASIR was observed in Central Sub-Saharan Africa [21,557.65 (95% UI: 16,639.4-27,491.48)] in 2019. From 1990 to 2019, the ASMR of malaria declined. Compared to other age cohorts, the ASIR, ASMR, and ASDR for children aged between 1 to 4 years were found to be higher. Worst-affected regions by malaria infection were the low-middle SDI region and low SDI region.

Conclusion

Malaria threatens global public health, especially in Central Sub-Saharan Africa and Western Sub-Saharan Africa. Children 1-4 years old continue to bear the most significant burden of malaria. The study's results will guide efforts to reduce malaria's impact on the global population.