Molecular epidemiology of rotavirus in four provinces of Angola before vaccine introduction.

Angola is a sub-Saharan country in southern Africa highly affected by diarrhoeal disease with limited epidemiological data regarding etiologic agents. This study was performed during 2012-2013, prior to rotavirus vaccine introduction, with the objective to detect and characterize the rotavirus strains circulating in four provinces of the country: Huambo, Luanda, Zaire, and Cabinda. A high rotavirus detection rate (35%, 117/334) was observed. G1 was the most common G-genotype (83.6%), whereas P[8] (50.9%) followed by P[6] (38.8%) were the most common P-types. G1P[8] was identified as the predominant combination (50%), followed by the unusual G1P[6] (29.3%). Strains such G2P[4], G8P[6], G9P[6], and G12P[6] were also found in lower frequencies (5.2-1.7%). The P[6] strains did not cluster in the phylogenetic trees according to their geographic origin or even the corresponding G-genotype, suggesting a limited number of recent introductions and extensive reassortment events. Our results represent the first report on rotavirus genotype profiles in Angola, showing a wide circulation of the unusual genotype G1P[6], and underline the importance of RV surveillance after the vaccine introduction. J. Med. Virol. 88:1511-1520, 2016. © 2016 Wiley Periodicals, Inc.

High efficacy of two artemisinin-based combinations (artesunate + amodiaquine and artemether + lumefantrine) in Caala, Central Angola.

In April 2004, 137 children 6-59 months of age with uncomplicated Plasmodium falciparum (Pf) malaria (Caala, Central Angola) were randomized to receive either artemether-lumefantrine (Coartem) or artesunate + amodiaquine (ASAQ). After 28 days of follow-up, there were 2/61 (3.2%) recurrent parasitemias in the Coartem group and 4/64 (6.2%) in the ASAQ group (P = 0.72), all classified as re-infections after PCR genotyping (cure rate = 100% [95%CI: 94-100] in both groups). Only one patient (ASAQ group) had gametocytes on day 28 versus five (Coartem) and three (ASAQ) at baseline. Compared with baseline, anemia was significantly improved after 28 days of follow-up in both groups (Coartem: from 54.1% to 13.4%; ASAQ: from 53.1% to 15.9%). Our findings are in favor of a high efficacy of both combinations in Caala. Now that Coartem has been chosen as the new first-line anti-malarial, the challenge is to insure that this drug is available and adequately used.

Antimalarial efficacy of chloroquine, amodiaquine, sulfadoxine-pyrimethamine, and the combinations of amodiaquine + artesunate and sulfadoxine-pyrimethamine + artesunate in Huambo and Bie provinces, central Angola.

We studied three antimalarial treatments in Caala and Kuito, Angola, in 2002 and 2003. We tested chloroquine (CQ), amodiaquine (AQ) and sulfadoxine-pyrimethamine (SP) in Caala, and AQ, SP and the combinations AQ+artesunate (AQ+AS) and SP+artesunate (SP+AS) in Kuito. A total of 619 children (240 in Caala, 379 in Kuito) with uncomplicated Plasmodium falciparum malaria were followed-up for 28 days, with PCR genotyping to distinguish recrudescence from reinfection. PCR-corrected failure proportions at day 28 were very high in the CQ group (83.5%, 95% CI 74.1-90.5), high in the SP groups (Caala: 25.3%, 95% CI 16.7-35.8; Kuito: 38.8%, 95% CI 28.4-50.0), around 20% in the AQ groups (Caala: 17.3%, 95% CI 10.0-27.2; Kuito: 21.6%, 95% CI 14.3-30.6) and very low in the artemisinin-based combination groups (1.2%, 95% CI 0.0-6.4 for each combination AQ+AS and SP+AS). These results show that CQ and SP are no longer efficacious in Caala and Kuito and that the moderate efficacy of AQ is likely to be compromised in the short term if used as monotherapy. We recommend the use of AQ with AS, though this combination might not have a long useful therapeutic life because of AQ resistance.