Placental impression smears is a good indicator of placental malaria in sub-Saharan Africa

Malaria, Urogenital Schistosomiasis, and Anaemia in Pregnant Ghanaian Women

Background

Anaemia is common in sub-Saharan Africa, and parasitic infections could worsen its burden during pregnancy. Moreover, women become susceptible to malaria during pregnancy. We investigated Plasmodium falciparum (P. falciparum) and Schistosoma haematobium (S. haematobium) infections and determined their association with anaemia during pregnancy.

Methods

A cross-sectional study involving 707 pregnant women attending antenatal care visits (ANC) and 446 at delivery was conducted in Battor and Adidome hospitals. Pregnant women were screened by microscopy and qPCR for P. falciparum and S. haematobium infections. Haemoglobin (Hb) levels were determined, and most participants received intermittent preventive treatment during pregnancy (IPTp) during ANC till delivery. Regression analyses were performed for associations between parasite infection and anaemia.

Results

P. falciparum microscopy prevalence at ANC and delivery was 8% and 2%, respectively, and by PCR 24% at ANC and 12% at delivery. Anaemia prevalence at ANC was 52% and 49% at delivery. There was an increased risk of anaemia with P. falciparum infection (aOR = 1.92; p = 0.04). IPTp (p = 0.003) and age (p = 0.004) were associated with increased Hb levels at delivery. S. haematobium prevalence by microscopy was 4% at ANC and 2% at delivery. No significant correlation between S. haematobium and Hb levels was observed (coef. = -0.62 g/dl; p = 0.07).

Conclusion

High anaemia prevalence was observed during pregnancy, and P. falciparum infection was associated with anaemia at ANC. Low S. haematobium prevalence could be attributed to previous praziquantel treatment during mass drug administration. Routine diagnosis and treatment of S. haematobium infections in endemic areas could be initiated to reduce schistosomiasis during pregnancy.

The effects of malaria in pregnancy on neurocognitive development in children at one and six years of age in Benin: a prospective mother-child cohort

Background

Malaria in pregnancy (MiP) contributes significantly to infant mortality rates in sub-Saharan Africa and has consequences on survivors, such as preterm birth and low birth weight. However, its impact on long-term neurocognitive development in children remains unknown.

Methods

Our prospective cohort included pregnant women and their live-born singletons from the Malaria in Pregnancy Preventive Alternative Drugs clinical trial. MiP was assessed using microscopy and real-time quantitative polymerase chain reaction (qPCR). Neurocognitive development in children was assessed using the Mullen Scales of Early Learning and the Kaufman Assessment Battery for Children, 2nd edition (KABC-II), at 1 and 6 years of age, respectively.

Results

Of 493 pregnant women, 196 (40%) were infected with malaria at least once: 121 (31%) with placental malaria diagnosed by qPCR. Multiple linear regression B-coefficients showed that impaired gross motor scores were associated with MiP at least once (−2.55; confidence interval [95% CI]: −5.15, 0.05), placental malaria by qPCR (−4.95; 95% CI: −7.65, −2.24), and high parasite density at delivery (−1.92; 95% CI: −3.86, 0.02) after adjustment. Malaria and high parasite density at the second antenatal care visit were associated with lower KABC-II Non-Verbal Index scores at 6 years (−2.57 [95% CI: −4.86, −0.28] and −1.91 [−3.51, −0.32]), respectively.

Conclusions

This prospective cohort study provides evidence that MiP, particularly late term, could have important negative consequences on child development at 1 and 6 years of age. Mechanisms behind this association must be further investigated and diagnostic methods in low-income countries should be strengthened to provide adequate treatment.

Clinical Trials Registration

NCT00811421.

Placental Malaria

Purpose of Review

Placental malaria is the primary mechanism through which malaria in pregnancy causes adverse perinatal outcomes. This review summarizes recent work on the significance, pathogenesis, diagnosis, and prevention of placental malaria.

Recent Findings

Placental malaria, characterized by the accumulation of Plasmodium-infected red blood cells in the placental intervillous space, leads to adverse perinatal outcomes such as stillbirth, low birth weight, preterm birth, and small-for-gestational-age neonates. Placental inflammatory responses may be primary drivers of these complications. Associated factors contributing to adverse outcomes include maternal gravidity, timing of perinatal infection, and parasite burden.

Summary

Placental malaria is an important cause of adverse birth outcomes in endemic regions. The main strategy to combat this is intermittent preventative treatment in pregnancy; however, increasing drug resistance threatens the efficacy of this approach. There are studies dissecting the inflammatory response to placental malaria, alternative preventative treatments, and in developing a vaccine for placental malaria.