Dynamics and features of transmission clusters of HIV-1 subtypes in the state of São Paulo, Brazil.

Background: Molecular epidemiology techniques allow us to track the HIV-1 transmission dynamics. Herein, we combined genetic, clinical and epidemiological data collected during routine clinical treatment to evaluate the dynamics and characteristics of transmission clusters of the most prevalent HIV-1 subtypes in the state of São Paulo, Brazil. Methods: This was a cross-sectional study conducted with 2,518 persons living with HIV (PLWH) from 53 cities in São Paulo state between Jan 2004 to Feb 2015. The phylogenetic tree of protease/reverse transcriptase (PR/RT) regions was reconstructed by PhyML and ClusterPicker used to infer the transmission clusters based on Shimodaira-Hasegawa (SH) greater than 90% (phylogenetic support) and genetic distance less than 6%. Results: Of a total of 2,518 sequences, 2,260 were pure subtypes at the PR/RT region, being B (88%), F1 (8.1%), and C (4%). About 21.2% were naïve with a transmitted drug resistance (TDR) rate of 11.8%. A total of 414 (18.3%) of the sequences clustered. These clusters were less evident in subtype B (17.7%) and F1 (15.1%) than in subtype C (40.2%). Clustered sequences were from PLWH at least 5 years younger than non-clustered among subtypes B (p < 0.001) and C (p = 0.037). Men who have sex with men (MSM) predominated the cluster in subtype B (51%), C (85.7%), and F1 (63.6%; p < 0.05). The TDR rate in clustered patients was 15.4, 13.6, and 3.1% for subtypes B, F1, and C, respectively. Most of the infections in subtypes B (80%), C (64%), and F1 (59%) occurred within the state of São Paulo. The metropolitan area of São Paulo presented a high level of endogenous clustering for subtypes B and C. The São Paulo city had 46% endogenous clusters of subtype C. Conclusion: Our findings showed that MSM, antiretroviral therapy in Treatment-Naive (ART-naïve) patients, and HIV1-C, played an important role in the HIV epidemic in the São Paulo state. Further studies in transmission clusters are needed to guide the prevention intervention.

Applying Next-Generation Sequencing to Track HIV-1 Drug Resistance Mutations Circulating in Portugal.

BACKGROUND: The global scale-up of antiretroviral treatment (ART) offers significant health benefits by suppressing HIV-1 replication and increasing CD4 cell counts. However, incomplete viral suppression poses a potential threat for the emergence of drug resistance mutations (DRMs), limiting ART options, and increasing HIV transmission. OBJECTIVE: We investigated the patterns of transmitted drug resistance (TDR) and acquired drug resistance (ADR) among HIV-1 patients in Portugal. METHODS: Data were obtained from 1050 HIV-1 patient samples submitted for HIV drug resistance (HIVDR) testing from January 2022 to June 2023. Evaluation of DRM affecting viral susceptibility to nucleoside/tide reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), and integrase strand transfer inhibitors (INSTIs) was performed using an NGS technology, the Vela Diagnostics Sentosa SQ HIV-1 Genotyping Assay. RESULTS: About 71% of patients were ART naïve and 29% were experienced. Overall, 20% presented with any DRM. The prevalence of TDR and ADR was 12.6% and 41.1%, respectively. M184V, T215S, and M41L mutations for NRTI, K103N for NNRTI, and M46I/L for PIs were frequent in naïve and treated patients. E138K and R263K mutations against INSTIs were more frequent in naïve than treated patients. TDR and ADR to INSTIs were 0.3% and 7%, respectively. Patients aged 50 or over (OR: 1.81, p = 0.015), originating from Portuguese-speaking African countries (PALOPs) (OR: 1.55, p = 0.050), HIV-1 subtype G (OR: 1.78, p = 0.010), and with CD4 < 200 cells/mm3 (OR: 1.70, p = 0.043) were more likely to present with DRMs, while the males (OR: 0.63, p = 0.003) with a viral load between 4.1 to 5.0 Log10 (OR: 0.55, p = 0.003) or greater than 5.0 Log10 (OR: 0.52, p < 0.001), had lower chances of presenting with DRMs. CONCLUSIONS: We present the first evidence on TDR and ADR to INSTI regimens in followed up patients presenting for healthcare in Portugal. We observed low levels of TDR to INSTIs among ART-naïve and moderate levels in ART-exposed patients. Regimens containing PIs could be an alternative second line in patients with intermediate or high-level drug resistance, especially against second-generation INSTIs (dolutegravir, bictegravir, and cabotegravir).

Blood count changes in malaria patients according to blood groups (ABO/Rh) and sickle cell trait.

INTRODUCTION: Introduction: Malaria continues to be the leading cause of hospitalization and death in Angola, a country in sub- Saharan Africa. In 2023, in the first quarter, 2,744,682 cases were registered, and of these 2,673 patients died due to malaria disease. Previous studies have shown that the ABO blood group can affect the progression of malaria to severe conditions after P. falciparum infection, while the sickle cell gene offers relative protection. OBJECTIVE: We investigated changes in the blood count according to blood groups (ABO/Rh) and sickle cell trait in patients with malaria in Luanda, capital of Angola. METHODOLOGY: This was a longitudinal, prospective and observational study with 198 patients hospitalized for malaria. RESULTS: Of the 198 patients studied, 13(6.6%) were ABRh(+), 4(2.0%) were ARh(-), 49(24.7%) were ARh(+), 42(21, 2%) were BRh (+), 5(2.5%) were ORh(-) and 85(42.9%) were ORh(+). For sickle cell trait, 145(73.2%) were AA, 37(18.7%) were AS and 16(8.1%) were SS. No statistical relationship was observed between age group, sex, parasitemia, clinical picture, hematocrit, MCV, HCM, MCHC, leukocytes, NEUT, LINF and PTL values with blood groups (p<0.05), but there was a relationship between values of hemoglobin and ABO/Rh blood groups (p>0.05). There was no relationship between age, parasitemia, clinical condition, MCV, HCM and MCHC values, leukocytes, NEUT and LINF with sickle cell trait (p<0.05), but there was a relationship between sex, hemoglobin and PTL and sickle cell values. sickle cell trait (p>0.05). CONCLUSION: It is imperative to differentiate patients with malaria based on blood groups and sickle cell trait, taking into account mainly the blood count parameters that demonstrate that there are patients who, depending on blood group or sickle cell trait, may react weakly to malaria infection regardless of the degree of parasitemia and medical prognosis.

Insights into SARS-CoV-2 in Angola during the COVID-19 peak: Molecular epidemiology and genome surveillance.

Background: In Angola, COVID-19 cases have been reported in all provinces, resulting in >105,000 cases and >1900 deaths. However, no detailed genomic surveillance into the introduction and spread of the SARS-CoV-2 virus has been conducted in Angola. We aimed to investigate the emergence and epidemic progression during the peak of the COVID-19 pandemic in Angola. Methods: We generated 1210 whole-genome SARS-CoV-2 sequences, contributing West African data to the global context, that were phylogenetically compared against global strains. Virus movement events were inferred using ancestral state reconstruction. Results: The epidemic in Angola was marked by four distinct waves of infection, dominated by 12 virus lineages, including VOCs, VOIs, and the VUM C.16, which was unique to South-Western Africa and circulated for an extended period within the region. Virus exchanges occurred between Angola and its neighboring countries, and strong links with Brazil and Portugal reflected the historical and cultural ties shared between these countries. The first case likely originated from southern Africa. Conclusion: A lack of a robust genome surveillance network and strong dependence on out-of-country sequencing limit real-time data generation to achieve timely disease outbreak responses, which remains of the utmost importance to mitigate future disease outbreaks in Angola.

Blood pressure pattern among blood donors exposed to SARS-CoV-2 in Luanda, Angola: A retrospective study.

Background and Aims: SARS-CoV-2 infection is a public health concern. Several aspects related to the pattern of infection remain unclear. This study aimed to investigate the blood pressure pattern among blood donors exposed to SARS-CoV-2 in Luanda, Angola, a sub-Saharan African country. Methods: We performed a retrospective analysis containing 343 blood donors from December 2019 to September 2020. Parametric tests compared means while χ 2 and logistic regression checked features associated with high blood pressure and were considered significant when p < 0.05. Results: The mean age of blood donors was 32.2 ± 8.81 years (ranging from 18 to 61 years) and 93% of the men's gender. Overall, 4.7% of the studied population had been exposed to SARS-CoV-2. High blood pressure prevalence increased from unexposed to exposed SARS-CoV-2 (6.7%-18.8%, p = 0.071). SARS-CoV-2 exposure increase systole (131 ± 12.2 mmHg to 136 ± 14.2 mmHg, p = 0.098), diastole (79.9 ± 9.53 mmHg to 84.2 ± 12.7 mmHg, p = 0.086), pulse in beats per minute (72.0 ± 11.1 to 73.7 ± 8.50, p = 0.553), and decrease donating time (6.31 ± 3.72 min to 5.48 ± 1.61 min, p = 0.371). Chances of having high blood pressure were high [OR: 3.20 (95% confidence interval [CI]: 0.85-12.1), p = 0.086] in exposed SARS-CoV-2. Donors exposed to SARS-CoV-2 with abnormal donation time increased from the donor up to 40 years to over 40 years (from 35.7% to 50%, p = 0.696). The mean systolic, diastolic, and pulse pressure were higher for non-O donors (p > 0.05). A significant link was observed, between the Rhesus factor and blood pressure status (p = 0.032). Conclusion: We showed important variations in blood pressure indices of the Angolan population exposed to SARS-CoV-2. Older age and non-O blood groups appear to be important biological factors for SARS-CoV-2 infection, as well as the risk of developing cardiovascular disease after or during SARS-CoV-2 exposure. Further studies assessing the impact on cardiovascular functions with ongoing or long-term SARS-CoV-2 exposure in individuals from resource-limited countries should be considered.

Demographic characteristics and risk factors related to high blood pressure among healthy blood donors from Luanda, Angola: A retrospective study.

Background and Aims: Hypertension is a public health concern, mainly in resource-limited countries. We investigated the characteristics and risk factors related to high blood pressure in healthy blood donors from, Luanda, the capital city of Angola. Methods: This was a retrospective study that included 343 healthy donors from December 2019 to September 2020. Results: The mean age was 32 ± 9 years. Men represented 93% of the population. Mean systolic blood pressure (SBP) was 131 ± 12.3 mmHg (ranging from 100 to 160 mmHg) and diastolic blood pressure (DBP) was 80.1 ± 9.72 mmHg (from 56.0 to 100 mmHg). DBP was related to age and gender (p < 0.05). About 7.3% of the donors had high-pressure (>140/90 mmHg). Age between 20 and 40 years (odds ratio [OR]: 2.52, p = 0.043), women (OR: 1.87, p = 0.548), nonurbanized areas (OR: 0.39, p = 0.067), high educational level (OR: 0.76, p = 0.637), employed (OR: 0.49, p = 0.491), voluntary donors (OR: 0.87, p = 0.799), blood group B (OR: 2.06, p = 0.346), and Rh- (OR: 0.26, p = 0.104), were potentially related with high-pressure. The high-pressure cases increased from December 2019 (4%) to September 2020 (28%) (p = 0.019). Conclusion: We showed high pressure among the healthy blood donors population. Demographic characteristics, ABO/Rh blood group, and year period are features that should be considered in cardiovascular disease control strategies. Biological and nonbiological features related to blood pressure changes should be considered for further studies in the Angolan population.

Immune profile of healthcare professionals six months after vaccination or exposure to SARS-CoV-2 in Angola.

Background and Aims: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a public health concern. Until 2021, more than 2 million cumulative deaths were reported worldwide. Herein, we investigated the immune profile of healthcare professionals 6 months after vaccination or exposure to SARS-CoV-2 in Angola. Methods: This was a prospective study conducted with 1068 Angolan healthcare professionals between August and December 2021. Participants were screened for the presence of IgG and IgM against SARS-CoV-2. Results: About 9.6% and 98.2% of the participants had prior exposure to SARS-CoV-2 or vaccination against it, respectively. Participants aged between 20 and 40 years (11.2%), female (12.4%), with higher educational level (12.8%), from Luanda (60.3%), and nonhealthcare professionals (8.1%) were the most affected by the SARS-CoV-2. Gender, education, and local residence were related to SARS-CoV-2 exposure (p < 0.05). About 7.3% and 98% of the exposed population developed IgM and IgG after 3 months of exposure, respectively. The AstraZeneca vaccine was the most used, followed by the Jonhson & Johnson and Sputinik. Almost all (98%) participants vaccinated with AstraZeneca had immunity >3 months. Individuals who received only the first dose regardless of the type of vaccine had a higher immunity duration (>3 months) than those who received two doses. For individuals who received the Sputnik and Johnson, the average immunity was lower (<3 months), especially among those who were older (over 40 years old) and exposed to SARS-CoV-2. Conclusion: We observed a high adherence rate to vaccination and a long immunity duration. The immunity duration depended on the type of vaccine. Further studies on the immunity profile in the population exposed to SARS-CoV-2 must be carried out in the general population from Angola to assess antibody-waning periods.

Clinical Features Related to Severity and Mortality among COVID-19 Patients in a Pre-Vaccine Period in Luanda, Angola.

Background: Infection due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with clinical features of diverse severity. Few studies investigated the severity and mortality predictors of coronavirus disease 2019 (COVID-19) in Africa. Herein, we investigated the clinical features of severity and mortality among COVID-19 patients in Luanda, Angola. Methods: This multicenter cohort study involved 101 COVID-19 patients, between December 2020 and April 2021, with clinical and laboratory data collected. Analysis was done using independent-sample t-tests and Chi-square tests. The results were deemed significant when p < 0.05. Results: The mean age of patients was 51 years (ranging from 18 to 80 years) and 60.4% were male. Fever (46%), cough (47%), gastrointestinal symptoms (26.7%), and asthenia (26.7%), were the most common symptoms. About 64.4% of the patients presented coexistent disorders, including hypertension (42%), diabetes (17%), and chronic renal diseases (6%). About 23% were non-severe, 77% were severe, and 10% died during hospitalization. Variations in the concentration of neutrophil, urea, creatinine, c-reactive protein, sodium, creatine kinase, and chloride were independently associated with severity and/or mortality (p < 0.05). Conclusion: Several factors contributed to the severity and mortality among COVID-19 patients in Angola. Further studies related to clinical features should be carried out to help clinical decision-making and follow-up of COVID-19 patients in Angola.

Molecular and genomic investigation of an urban outbreak of dengue virus serotype 2 in Angola, 2017-2019.

BACKGROUND: The transmission patterns and genetic diversity of dengue virus (DENV) circulating in Africa remain poorly understood. Circulation of the DENV serotype 1 (DENV1) in Angola was detected in 2013, while DENV serotype 2 (DENV2) was detected in 2018. Here, we report results from molecular and genomic investigations conducted at the Ministry of Health national reference laboratory (INIS) in Angola on suspected dengue cases detected between January 2017 and February 2019. METHODS: A total of 401 serum samples from dengue suspected cases were collected in 13 of the 18 provinces in Angola. Of those, 351 samples had complete data for demographic and epidemiological analysis, including age, gender, province, type of residence, clinical symptoms, as well as dates of onset of symptoms and sample collection. RNA was extracted from residual samples and tested for DENV-RNA using two distinct real time RT-PCR protocols. On-site whole genome nanopore sequencing was performed on RT-PCR+ samples. Bayesian coalescent models were used to estimate date and origin of outbreak emergence, as well as population growth rates. RESULTS: Molecular screening showed that 66 out of 351 (19%) suspected cases were DENV-RNA positive across 5 provinces in Angola. DENV RT-PCR+ cases were detected more frequently in urban sites compared to rural sites. Of the DENV RT-PCR+ cases most were collected within 6 days of symptom onset. 93% of infections were confirmed by serotype-specific RT-PCR as DENV2 and 1 case (1.4%) was confirmed as DENV1. Six CHIKV RT-PCR+ cases were also detected during the study period, including 1 co-infection of CHIKV with DENV1. Most cases (87%) were detected in Luanda during the rainy season between April and October. Symptoms associated with severe dengue were observed in 11 patients, including 2 with a fatal outcome. On-site nanopore genome sequencing followed by genetic analysis revealed an introduction of DENV2 Cosmopolitan genotype (also known as DENV2-II genotype) possibly from India in or around October 2015, at least 1 year before its detection in the country. Coalescent models suggest relatively moderately rapid epidemic growth rates and doubling times, and a moderate expansion of DENV2 in Angola during the studied period. CONCLUSION: This study describes genomic, epidemiological and demographic characteristic of predominately urban transmission of DENV2 in Angola. We also find co-circulation of DENV2 with DENV1 and CHIKV and report several RT-PCR confirmed severe dengue cases in the country. Increasing dengue awareness in healthcare professional, expanding the monitorization of arboviral epidemics across the country, identifying most common mosquito breeding sites in urban settings, implementing innovative vector control interventions and dengue vaccination campaigns could help to reduce vector presence and DENV transmission in Angola.

Evaluation of blood cell count parameters as predictors of treatment failure of malaria in Angola: An observational study.

BACKGROUND: Despite the guidelines provided by the World Health Organization for the treatment of malaria, treatment failure occurs in many hospitalized patients. OBJECTIVE: Evaluate whether blood cell count parameters may serve as predictors for malaria treatment. METHODOLOGY: A cross-sectional study with a quantitative approach. RESULTS: Of the 219 patients, 21.5% showed failure to antimalarial treatment, Patient with 21 and 40 years (72.6%), male (53.4%), from peri-urban area (47.5%), with high parasitemia (59.8%), treated with Arthemeter (90.9%) and the mortality were 5.9%. Significant associations were observed between occupation, level of parasitemia and outcome with resistance to antimalarial treatment (p<0.05). Patients with normal Hb [OR: 0.75 (95% CI: 0.39-1.44), p = 0.393], RBC [OR: 0.83 (95% CI: 0.40-1.72), p = 0.632], RDW [OR: 0.54 (95% CI: 0.27-1.09), p = 0.088], MCV [OR: 0.61 (95% CI: 0.28-1.31), p = 0.204] were less likely to have malaria treatment failures after artemisinin-based therapy failure. In contrast, those with normal values of segmented neutrophils [OR: 0.32 (95% CI: 0.11-0.96), p = 0.042] and lymphocyte counts [OR: 0.24 (95% CI: 0.05-1.04), p = 0.055]. We also found that patients with significant low levels of Hct [OR: 0.31 (95% CI: 0.15-0.64) p = 0.002], and high leukocytes [OR: 8.88 (95% CI: 2.02-37.2), p = 0.004] and normal platelet values [OR: 1.42 (95% CI: 0.73-2.95), p = 0.280] demonstrated high probability of treatment failure. CONCLUSION: The importance of blood cell count parameters in monitoring malaria therapy necessitates the urgent need to re-evaluate Artemether-based therapy. Future studies involving more participants in different settings are needed to provide further evidence.

Factors Associated With Resistance to In-Hospital Treatment of Malaria in Angolan Patients.

Background: Malaria is a public health problem, particularly in low- and middle-income countries. In Angola, it is the leading cause of death, morbidity, and absenteeism from work and school. Objective: To evaluate the social and clinical factors associated with resistance to in-hospital treatment. Methodology: A prospective analytical cross-sectional study with a quantitative approach was conducted including 220 patients with malaria. Results: Of the 220 patients enrolled, the majority were between 21 and 40 years old (72.7%), male (53.6%), of peri-urban areas (47.7%), employees (46.4%), and with high parasitemia levels (57.7%). Of the remaining hospitalized patients (61.4%), 20.9% were resistant to treatment. The resistance risk was higher in patients over 40 years [OR: 5.91 (95% CI: 0.76-45.7), P = .088], from rural regions [OR: 2.48 (95% CI: 0.95-6.48), P = .064], that were unemployed [OR: 1.06 (95% CI: 0.52-2.15), P = .859], presenting high parasitemia [OR: 1.95 (95% CI: 1.02-3.75), P = .043] and who remained hospitalized [OR: 5.28 (95% CI: 0.63-43.1), P = .121]. The risk to develop resistance was lower in patients that were students [OR: 0.04 (95% CI: 0.01-0.37), P = .004], patients who were treated with dipyrone [OR: 0.06 (95% CI: 0.01-0.24), P < .001], metoclopramide [OR: 0.25 (95% CI: 0.09-0.67), P = .006] and ciprofloxacin [OR: 0.22 (95% CI: 0.11-0.44), P < .001]. Conclusion: Treatment with antimalarial drugs as well as the use of adjuvants such as dipyrone, metoclopramide, ciprofloxacin, and diazepam can reduce the chances of developing resistance to malaria treatment, however, it is necessary to carry out further in-depth studies.

Early Evidence of Circulating SARS-CoV-2 in Unvaccinated and Vaccinated Measles Patients, September 2019-February 2020.

BACKGROUND: The global emergence of coronavirus disease 2019 (COVID-19) has challenged healthcare and rapidly spread over the globe. Early detection of new infections is crucial in the control of emerging diseases. Evidence of early recorded COVID-19 cases outside China has been documented in various countries. In this study, we aimed to identify the time of SARS-CoV-2 infection circulation by retrospectively analyzing sera of measles patients, weeks before the reported first COVID-19 cases in Angola. MATERIALS AND METHODS: We examined the humoral response against SARS-CoV-2 by using an enzyme-linked immunosorbent assay (ELISA)-based assay on a combined two-step sandwich enzyme immunoassay method. In total, we received 568 study patients with blood specimens collected from 23 September 2019 to 28 February 2020, 442 sera samples that met the criteria of the study were withdrawn and selected from the overall 568 received samples. In this study, we considered seropositives, patients who tested positive for SARS-CoV-2 immunoglobulin G (IgG) and M (IgM) antibodies with the index value >1. RESULTS: Of the 442 sera samples that met the criteria of the study, 204 were measles seropositive. Forty out of 204 were confirmed reactive to SARS-CoV-2 viral proteins using IgG and IgM more than 2 weeks before the first reported case in Angola. The humoral response analysis showed significant differences (p = 0.01) between the IgG and IgM indexes in the unvaccinated measles patients. Similarly, a significant difference (p = 0.001) was seen between the IgG and IgM indexes in the vaccinated measles patients. CONCLUSION: Here, using the humoral response analysis, we report the identification of early circulation SARS-CoV-2 infection weeks before the first recognized cases in the Republic of Angola.

Epidemiological Characteristics and Risk Factors Related to Drug-resistant Tuberculosis in Luanda, Angola.

Tuberculosis (TB) is a major cause of illness and public health concern, especially in resource-limited countries. This study analyzed the characteristics related to anti-TB drug resistance. Moreover, we examined the evidence-based indications for the treatment of active TB in Angola. This study evaluated the medical records of 176 patients screened for TB from January to September 2016 in Luanda, the capital city of Angola. Approximately 66.5% of the patients were newly diagnosed with active TB. The residence area showed a significant relationship with TB (P = 0.025), whereas age group (P = 0.272), gender (P = 0.853), and HIV status (P = 0.284) did not showed any relationship with TB. Overall, 72.4% of TB patients had resistance to at least one of the anti-TB drugs. The risk of anti-TB drug resistance was higher in males (odds ratio [OR]: 1.22; 95% confidence interval [CI]: 0.42-3.58, P = 0.685] and in TB-HIV coinfected patients [OR: 1.39; (95% CI: 0.26-7.28), P = 0.700], whereas it was lower in patients aged 30 years or older (OR: 0.56; 95% CI: 0.18-1.69) P = 0.303) and in patients living in urbanized areas (OR: 0.74; 95% CI: 0.17-3.25; P = 0.685). Our findings showed that drug-resistant TB is emerging in Angola. Further studies on factors related to anti-TB drug resistance are urgently needed to ascertain the magnitude of the problem and to proffer strategies toward TB control in Angola.

Coinfection between SARS-CoV-2 and vector-borne diseases in Luanda, Angola.

Co-epidemics happening simultaneously can generate a burden on healthcare systems. The co-occurrence of SARS-CoV-2 with vector-borne diseases (VBD), such as malaria and dengue in resource-limited settings represents an additional challenge to the healthcare systems. Herein, we assessed the coinfection rate between SARS-CoV-2 and VBD to highlight the need to carry out an accurate diagnosis and promote timely measures for these infections in Luanda, the capital city of Angola. This was a cross-sectional study conducted with 105 subjects tested for the SARS-CoV-2 and VBD with a rapid detection test in April 2021. The participants tested positive for SARS-CoV-2 (3.80%), malaria (13.3%), and dengue (27.6%). Low odds related to testing positivity to SARS-CoV-2 or VBD were observed in participants above or equal to 40 years (odds ratio [OR]: 0.60, p = 0.536), while higher odds were observed in male (OR: 1.44, p = 0.392) and urbanized areas (OR: 3.78, p = 0.223). The overall co-infection rate between SARS-CoV-2 and VBD was 11.4%. Our findings showed a coinfection between SARS-CoV-2 with malaria and dengue, which could indicate the need to integrate the screening for VBD in the SARS-CoV-2 testing algorithm and the adjustment of treatment protocols. Further studies are warranted to better elucidate the relationship between COVID-19 and VBD in Angola.

Seroprevalence of anti-SARS-CoV-2 antibodies and risk factors among healthy blood donors in Luanda, Angola.

BACKGROUND: SARS-CoV-2 emerged in China and spread throughout the world due to its rapid transmission. The exposure rate in the healthy population is unknown, mainly in resource-limited countries. Herein, we estimated the seroprevalence of anti-SARS-CoV-2 antibodies and risk factors among blood donors in Luanda, the capital city of Angola. METHODS: This was a retrospective study conducted with 343 blood donors. Chi-square and logistic regression were calculated to predict the independent variable for SARS-CoV-2 infection and deemed significant when p < 0.05. RESULTS: Seroprevalence of anti-SARS-CoV-2 was 4.7%. Positivity rates varied to age groups (3.5-14.3%), gender (0-5%), area of residence (3.1-.6%), educational level (5.1-10.2%), occupation (4.4-7.7%), and the blood donor category (2.0-5.1%). Past and recent infections were detected in 3.2% and 1.5%, respectively. Blood donors under the age of 20 years (OR: 4.58, p = 0.241) and from non-urbanized areas (OR: 1.86, p = 0.293) presented a high risk related to infection. The infection was higher in blood group A and lower in blood group O. The risk of SARS-CoV-2 infection has increased from January 2020 (OR: 0.03, p = 0.001) to August 2020 (OR: 0.57, p = 0.426). CONCLUSIONS: We provide an estimate of the exposure of healthy blood donors in Luanda. Also, we detected anti-SARS-CoV-2 in January 2020, indicating that the SARS-CoV-2 could have been imported during the first month of 2020. Further studies should be performed to assess the exposure rate in different groups from Angola.

Development of Triazoles and Triazolium Salts Based on AZT and Their Anti-Viral Activity against HIV-1.

We report herein a set of 3'-azido-3'-deoxythymidine (AZT) derivatives based on triazoles and triazolium salts for HIV-1 infection. The compounds were synthesized via click chemistry with Cu(I) and Ru(II) catalysts. Triazolium salts were synthesized by reaction with methyl iodide or methyl triflate in good yields. The antiviral activity of the compounds was tested using two methodologies: In method one the activity was measured on infected cells; in method two a pre-exposure prophylaxis experimental model was employed. For method one the activity of the compounds was moderate, and in general the triazolium salts showed a decreased activity in relation to their triazole precursors. With method two the antiviral activity was higher. All compounds were able to decrease the infection, with two compounds able to clear almost all the infection, while a lower antiviral activity was noted for the triazolium salts. These results suggest that these drugs could play an important role in the development of pre-exposure prophylaxis therapies.

Prevalence and Risk Factors of SARS-CoV-2 Infection among Parturients and Newborns from Luanda, Angola.

SARS-CoV-2 emerged in China in December 2019, creating a massive public health concern. Although previous studies have identified SARS-CoV-2 in pregnant women, the possibility of transmission to newborns remains uncertain. Herein, we investigated SARS-CoV-2 infection and risk factors among parturients and newborns. This was a cross-sectional study carried out with 3633 parturients from Luanda, Angola, between January and April 2021, with an age ranging from 13 to 48 years. SARS-CoV-2 infection of the parturients was further confirmed with RT-PCR after COVID-19 Ag Rapid Testing. About 0.4% of parturients tested positive on the day of delivery. Surprisingly, parturients from urbanized areas (OR: 0.18, p = 0.025) had a low chance of infection. None of the newborns tested positive in the first 24 h after birth, while one (9.1%, 1/10) of the newborns tested positive with pharyngeal swabs seven days after birth. However, whether the case was due to vertical transmission from mother to child remains to be confirmed. The mother's residence, education level, antenatal follow-up, and delivery category were related to SARS-CoV-2 transmission (p < 0.05). Our findings showed a relatively low SARS-CoV-2 infection from parturients to newborns, regardless of the severity of the maternal disease. Furthermore, these findings are an early assessment of COVID-19 cases in late pregnancy, which could indicate the need for intensive management of SARS-CoV-2 infection among parturients in Angola. Further studies are needed on the consequences of SARS-CoV-2 among pregnant women and neonates from Angola.

Correction: Sociodemographic characteristics and risk factors related to SARS-CoV-2 infection in Luanda, Angola.

[This corrects the article DOI: 10.1371/journal.pone.0249249.].

Factors Influencing HIV Drug Resistance among Pregnant Women in Luanda, Angola: Findings from a Cross-Sectional Study.

The increase in HIV infection and drug-resistant strains is an important public health concern, especially in resource-limited settings. However, the identification of factors related to the propagation of infectious diseases represents a crucial target offering an opportunity to reduce health care costs as well as deepening the focus on preventing infection in high-risk groups. In this study, we investigate the factors related to drug resistance among HIV-infected pregnant women in Luanda, the capital city of Angola. This was a part of a cross-sectional study conducted with 42 HIV-positive pregnant women. A blood sample was collected, and HIV-1 genotyping was carried out using an in-house method. Multivariate analyses were performed to determine the interaction between sociodemographic characteristics and drug resistance. HIV drug resistance was detected in 44.1% of the studied population. High probabilities of drug resistance were observed for HIV-infected pregnant women living in rural areas (AOR: 2.73; 95% CI: 0.50-14.9) with high educational level (AOR: 6.27; 95% CI: 0.77-51.2) and comorbidities (AOR: 5.47; 95% CI: 0.28-106) and infected with a HIV-1 non-B subtype other than subtype C (AOR: 1.60; 95% CI: 0.25-10.3). The present study reports high HIV drug resistance. Furthermore, older-age, rural areas, high educational levels, unemployed status, having comorbidities, and HIV-1 subtypes were factors related to drug resistance. These factors impact on drug susceptibility and need to be urgently addressed in order to promote health education campaigns able to prevent the spread of drug-resistant HIV strains in Angola.