Pre-Pandemic Cross-Reactive Immunity against SARS-CoV-2 among Central and West African Populations.

For more than two years after the emergence of COVID-19 (Coronavirus Disease-2019), significant regional differences in morbidity persist. These differences clearly show lower incidence rates in several regions of the African and Asian continents. The work reported here aimed to test the hypothesis of a pre-pandemic natural immunity acquired by some human populations in central and western Africa, which would, therefore, pose the hypothesis of an original antigenic sin with a virus antigenically close to the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

Evaluation of the application of national malaria treatment guidelines in private pharmacies in a rural area in the Democratic Republic of Congo.

In the Democratic Republic of the Congo, the first recourse in case of suspected malaria in the health system is the private pharmacy sector. This study was therefore designed to assess private provider adherence to national case management guidelines in Kimpese, a rural area of Central Kongo province. A descriptive cross-sectional survey of 103 pharmacies took place in March 2016.

Antimalarial Activity of Human Group IIA Secreted Phospholipase A in Relation to Enzymatic Hydrolysis of Oxidized Lipoproteins.

The level of human group IIA secreted phospholipase A (hGIIA sPLA) is increased in the plasma of malaria patients, but its role is unknown. In parasite culture with normal plasma, hGIIA is inactive against , contrasting with hGIIF, hGV, and hGX sPLAs, which readily hydrolyze plasma lipoproteins, release nonesterified fatty acids (NEFAs), and inhibit parasite growth. Here, we revisited the anti- activity of hGIIA under conditions closer to those of malaria physiopathology where lipoproteins are oxidized.

Design and synthesis of simplified speciophylline analogues and β-carbolines as active molecules against Plasmodium falciparum.

A structure-activity relationship study of active molecules against chloroquine-resistant Plasmodium falciparum K1 strain is reported. Structurally simplified analogues of antiplasmodial active alkaloids presented similar levels of activity as their corresponding natural products extracted from Guiera senegalensis and Mitragyna inermis with IC values on chloroquine-resistant P. falciparum K1 strain of up to 10.

Prevalence of Plasmodium falciparum parasites resistant to sulfadoxine/pyrimethamine in the Democratic Republic of the Congo: emergence of highly resistant pfdhfr/pfdhps alleles.

Background: In 2005, the Democratic Republic of the Congo (DRC) switched to artesunate/amodiaquine as the first-line antimalarial in response to increasing sulfadoxine/pyrimethamine resistance and adopted intermittent preventive treatment using sulfadoxine/pyrimethamine in pregnancy.

Objectives: To determine the prevalence of molecular markers of sulfadoxine/pyrimethamine resistance in southwestern DRC 10 years after the new policy was instituted.

Methods: From March 2014 to December 2015, blood samples were collected from symptomatic patients presenting to outpatient centres in urban and rural areas.