Genetic diversity and natural selection on the thrombospondin-related adhesive protein (TRAP) gene of Plasmodium falciparum on Bioko Island, Equatorial Guinea and global comparative analysis.

BACKGROUND: Thrombospondin-related adhesive protein (TRAP) is a transmembrane protein that plays a crucial role during the invasion of Plasmodium falciparum into liver cells. As a potential malaria vaccine candidate, the genetic diversity and natural selection of PfTRAP was assessed and the global PfTRAP polymorphism pattern was described. METHODS: 153 blood spot samples from Bioko malaria patients were collected during 2016-2018 and the target TRAP gene was amplified. Together with the sequences from database, nucleotide diversity and natural selection analysis, and the structural prediction were preformed using bioinformatical tools. RESULTS: A total of 119 Bioko PfTRAP sequences were amplified successfully. On Bioko Island, PfTRAP shows its high degree of genetic diversity and heterogeneity, with π value for 0.01046 and Hd for 0.99. The value of dN-dS (6.2231, p < 0.05) hinted at natural selection of PfTRAP on Bioko Island. Globally, the African PfTRAPs showed more diverse than the Asian ones, and significant genetic differentiation was discovered by the fixation index between African and Asian countries (Fst > 0.15, p < 0.05). 667 Asian isolates clustered in 136 haplotypes and 739 African isolates clustered in 528 haplotypes by network analysis. The mutations I116T, L221I, Y128F, G228V and P299S were predicted as probably damaging by PolyPhen online service, while mutations L49V, R285G, R285S, P299S and K421N would lead to a significant increase of free energy difference (ΔΔG > 1) indicated a destabilization of protein structure. CONCLUSIONS: Evidences in the present investigation supported that PfTRAP gene from Bioko Island and other malaria endemic countries is highly polymorphic (especially at T cell epitopes), which provided the genetic information background for developing an PfTRAP-based universal effective vaccine. Moreover, some mutations have been shown to be detrimental to the protein structure or function and deserve further study and continuous monitoring.

Immunogenicity and Protective Efficacy of Radiation-Attenuated and Chemo-Attenuated PfSPZ Vaccines in Equatoguinean Adults.

Plasmodium falciparum sporozoite (PfSPZ) Vaccine (radiation-attenuated, aseptic, purified, cryopreserved PfSPZ) and PfSPZ-CVac (infectious, aseptic, purified, cryopreserved PfSPZ administered to subjects taking weekly chloroquine chemoprophylaxis) have shown vaccine efficacies (VEs) of 100% against homologous controlled human malaria infection (CHMI) in nonimmune adults. Plasmodium falciparum sporozoite-CVac has never been assessed against CHMI in African vaccinees. We assessed the safety, immunogenicity, and VE against homologous CHMI of three doses of 2.7 × 106 PfSPZ of PfSPZ Vaccine at 8-week intervals and three doses of 1.0 × 105 PfSPZ of PfSPZ-CVac at 4-week intervals with each arm randomized, double-blind, placebo-controlled, and conducted in parallel. There were no differences in solicited adverse events between vaccinees and normal saline controls, or between PfSPZ Vaccine and PfSPZ-CVac recipients during the 6 days after administration of investigational product. However, from days 7-13, PfSPZ-CVac recipients had significantly more AEs, probably because of Pf parasitemia. Antibody responses were 2.9 times higher in PfSPZ Vaccine recipients than PfSPZ-CVac recipients at time of CHMI. Vaccine efficacy at a median of 14 weeks after last PfSPZ-CVac dose was 55% (8 of 13, P = 0.051) and at a median of 15 weeks after last PfSPZ Vaccine dose was 27% (5 of 15, P = 0.32). The higher VE in PfSPZ-CVac recipients of 55% with a 27-fold lower dose was likely a result of later stage parasite maturation in the liver, leading to induction of cellular immunity against a greater quantity and broader array of antigens.

Providing Ancillary Care in Clinical Research: A Case of Diffuse Large B-Cell Lymphoma during a Malaria Vaccine Trial in Equatorial Guinea.

Providing medical care for participants in clinical trials in resource-limited settings can be challenging and costly. Evaluation and treatment of a young man who developed cervical lymphadenopathy during a malaria vaccine trial in Equatorial Guinea required concerted efforts of a multinational, multidisciplinary team. Once a diagnosis of diffuse large B-cell lymphoma was made, the patient was taken to India to receive immunochemotherapy. This case demonstrates how high-quality medical care was provided for a serious illness that occurred during a trial that was conducted in a setting in which positron emission tomography for diagnostic staging, an oncologist for supervision of treatment, and an optimal therapeutic intervention were not available. Clinical researchers should anticipate the occurrence of medical conditions among study subjects, clearly delineate the extent to which health care will be provided, and set aside funds commensurate with those commitments.

Cardiovascular Disease Epidemiology in Portuguese-Speaking Countries: data from the Global Burden of Disease, 1990 to 2016 / Epidemiologia das Doenças Cardiovasculares em Países de Língua Portuguesa: Dados do "Global Burden of Disease", 1990 a 2016

Abstract Background: Portuguese-speaking countries (PSC) share the influence of the Portuguese culture but have socioeconomic development patterns that differ from that of Portugal. Objective: To describe trends in cardiovascular disease (CVD) morbidity and mortality in the PSC between 1990 and 2016, stratified by sex, and their association with the respective sociodemographic indexes (SDI). Methods: This study used the Global Burden of Disease (GBD) 2016 data and methodology. Data collection followed international standards for death certification, through information systems on vital statistics and mortality surveillance, surveys, and hospital registries. Techniques were used to standardize causes of death by the direct method, as were corrections for underreporting of deaths and garbage codes. To determine the number of deaths due to each cause, the CODEm (Cause of Death Ensemble Model) algorithm was applied. Disability-adjusted life years (DALYs) and SDI (income per capita, educational attainment and total fertility rate) were estimated for each country. A p-value <0.05 was considered significant. Results: There are large differences, mainly related to socioeconomic conditions, in the relative impact of CVD burden in PSC. Among CVD, ischemic heart disease was the leading cause of death in all PSC in 2016, except for Mozambique and Sao Tome and Principe, where cerebrovascular diseases have supplanted it. The most relevant attributable risk factors for CVD among all PSC are hypertension and dietary factors. Conclusion: Collaboration among PSC may allow successful experiences in combating CVD to be shared between those countries.

Resumo Fundamento: Os países de língua portuguesa (PLP) partilham a influência da cultura portuguesa com desenvolvimento socioeconômico diverso de Portugal. Objetivo: Descrever as tendências de morbidade e mortalidade por doenças cardiovasculares (DCV) nos PLP, entre 1990 e 2016, estratificadas por sexo, e sua associação com os respectivos índices sociodemográficos (SDI). Métodos: O estudo utilizou dados e metodologia do Global Burden of Disease (GBD) 2016. As informações seguiram padrões internacionais de certificação de óbito, através de sistemas de informação sobre estatísticas vitais e vigilância da mortalidade, pesquisas e registros hospitalares. Empregaram-se técnicas para padronização das causas de morte pelo método direto, e correções para sub-registro dos óbitos e garbage codes. Para determinar o número de mortes por cada causa, aplicou-se o algoritmo CODEm (Modelagem Agrupada de Causas de Morte). Estimaram-se os anos saudáveis de vida perdidos (DALYs) e o SDI (renda per capita, nível de escolaridade e taxa de fertilidade total) para cada país. Resultados: Existem grandes diferenças na importância relativa da carga de DCV nos PLP relacionadas principalmente às condições socioeconômicas. Entre as DCV, a doença isquêmica do coração foi a principal causa de morte nos PLP em 2016, com exceção de Moçambique e São Tomé e Príncipe, onde as doenças cerebrovasculares a suplantaram. Os fatores de risco atribuíveis mais relevantes para as DCV entre os PLP foram a hipertensão arterial e os fatores dietéticos. Um valor de p < 0,05 foi considerado significativo. Conclusão: A colaboração entre os PLP poderá permitir que experiências exitosas no combate às DCV sejam compartilhadas entre esses países.

Limited artemisinin resistance-associated polymorphisms in Plasmodium falciparum K13-propeller and PfATPase6 gene isolated from Bioko Island, Equatorial Guinea.

OBJECTIVE: With emergence and geographically expanding of antimalarial resistance worldwide, molecular markers are essential tool for surveillance of resistant Plasmodium parasites. Recently, single-nucleotide polymorphisms (SNPs) in the PF3D7_1343700 kelch propeller (K13-propeller) domain are shown to be associated with artemisinin (ART) resistance in vivo and in vitro. This study aims to investigate the ART resistance-associated polymorphisms of K13-propeller and PfATPase6 genes in Plasmodium falciparum isolates from Bioko Island, Equatorial Guinea (EG). METHODS: A total of 172 samples were collected from falciparum malaria patients on Bioko Island between 2013 and 2014. The polymorphisms of K13-propeller and PfATPase6 genes were analyzed by Nest-PCR and sequencing. RESULTS: Sequences of K13-propeller and PfATPase6 were obtained from 90.74% (98/108) and 91.45% (139/152) samples, respectively. The 2.04% (2/98) cases had non-synonymous K13-propeller A578S mutation but no found the mutations associated with ART resistance in Southeast Asia. For PfATPase6, the mutations were found at positions N569K and A630S with the mutation prevalence of 7.91% (11/139) and 1.44% (2/139), respectively. In addition, a sample with the mixed type at position I723V was discovered (0.72%, 1/139). CONCLUSIONS: This study initially offers an insight of K13-propeller and PfATPase6 polymorphisms on Bioko Island, EG. It suggests no widespread ART resistance or tolerance in the region, and might be helpful for developing and updating guidance for the use of ART-based combination therapies (ACTs).

Seroprevalence of Human Immunodeficiency Virus, Hepatitis B Virus, Hepatitis C Virus, and Treponema pallidum Infections among Blood Donors on Bioko Island, Equatorial Guinea.

BACKGROUND: Regular screening of transfusion-transmissible infections (TTIs), such as human immunodeficiency virus (HIV), hepatitis B and hepatitis C virus (HBV and HCV, respectively), and Treponema pallidum, in blood donors is essential to guaranteeing clinical transfusion safety. This study aimed to determine the seroprevalence of four TTIs among blood donors on Bioko Island, Equatorial Guinea (EG). METHODS: A retrospective survey of blood donors from January 2011 to April 2013 was conducted to assess the presence of HIV, HBV, HCV and T. pallidum. The medical records were analyzed to verify the seroprevalence of these TTIs among blood donations stratified by gender, age and geographical region. RESULTS: Of the total 2937 consecutive blood donors, 1098 (37.39%) had a minimum of one TTI and 185 (6.29%) harbored co-infections. The general seroprevalence of HIV, HBV, HCV and T. pallidum were 7.83%, 10.01%, 3.71% and 21.51%, respectively. The most frequent TTI co-infections were HBV-T. pallidum 60 (2.04%) and HIV-T. pallidum 46 (1.57%). The seroprevalence of HIV, HBV, HCV and T. pallidum were highest among blood donors 38 to 47 years, 18 to 27 years and ≥ 48 years age, respectively (P<0.05). The seroprevalence of TTIs varied according to the population from which the blood was collected on Bioko Island. CONCLUSIONS: Our results firstly provide a comprehensive overview of TTIs among blood donors on Bioko Island. Strict screening of blood donors and improved hematological examinations using standard operating procedures are recommended.

Prevalence of intestinal parasites in HIV-positive patients on the island of Bioko, Equatorial Guinea: its relation to sanitary conditions and socioeconomic factors.

The prevalence of intestinal parasitic diseases and their associated factors has been investigated in HIV populations from the Island of Bioko, Equatorial Guinea. The feces of 310 participants from the island of Bioko (260 HIV-positive and 50 HIV-negative) were analyzed by microscopic observation. Immunochromatography was also used to diagnose Giardia, Entamoeba histolytica and Cryptosporidium spp. In addition, patients were asked for sociodemographic, economic and academic status, and CD4+ T cell counts were recorded. For HIV-positive patients, the prevalence of infection by intestinal parasites was 81.5% (212/260), 83.8% (218/260) by pathogenic helminths and 55.4% (168/260) by pathogenic protozoa (E. histolytica/dispar and Giardia duodenalis). Gender association was found between the infection by Ascaris and Schistosoma, a higher proportion being found in women; and between Entamoeba and the place of residence, a higher proportion being observed in the urban belt. Strongyloides stercoralis and Chilomastix mesnili appeared only in the people of this group, all the cases of Chilomastix being in females. For HIV-negative participants, the prevalence of infection by intestinal parasites was 74.0% (37/50), 90.0% (45/50) by pathogenic helminths and 66.0% (43/50) by pathogenic protozoa. Gender, educational level and low hygiene were associated with intestinal parasitic infection. When comparing the two groups (HIV-positive and HIV-negative), statistical association between HIV co-infection and infection by Giardia and Entamoeba was found. Diarrhea was also associated with intestinal parasitic infection in the HIV-positive group. Not only do our findings reflect high rates of intestinal parasitic infections in HIV-positive people, but also in the HIV-negative group, suggesting a closer relationship between sanitary status and living conditions than with immune status, and thus they highlight the need to carry out health education policies in the population. In addition, Schistosoma intercalatum/guineensis has been detected for the first time as an autochthonous parasite on the island.

Dysplastic tracheae in eight blue duikers (Cephalophus monticola) from Bioko, Equatorial Guinea.

Nine blue duikers (Cephalophus monticola), purchased in the Malabo bushmeat market, were necropsied. Eight of the nine animals were found to have dysplastic tracheas, characterized by lateral apposition of tracheal rings, entrapment of the trachealis muscle and annular ligaments, and bunching of the tracheal epithelium. Communications with zoologic pathologists and a thorough search of the veterinary literature have not uncovered a single case of this pathologic finding. As such, this finding may represent an evolutionary marker indicative of a bottleneck that may have occurred in the history of this species of duiker, endemic to the island of Bioko, in the Gulf of Benin.

A new subtype of hepatitis C virus genotype 1: complete genome and phylogenetic relationships of an Equatorial Guinea isolate.

Hepatitis C virus (HCV) is the leading cause of chronic liver disease and is associated with hepatocellular carcinoma. However, there have been few studies on the distribution and genetic diversity of HCV isolates in non-developed countries. Here, the complete genome sequence of an HCV genotype 1 isolate from Equatorial Guinea is reported, the first complete HCV-1 genome of African origin. Phylogenetic analysis revealed that this sequence always grouped with sequences of genotype 1, but did not group clearly with any subtype described so far. An analysis of partial NS5B gene sequences with additional sequences of African origin also failed to find close similarities between the new sequence and any previously known isolate. Genetic divergence of the coding region of this new sequence with respect to the recognized subtypes of HCV-1 ranged from 20 to 22%. It is proposed that this isolate is a representative of a new, distinct variant of HCV subtype 1.

[Maternal morbidity associated with delivery apropos of 124 cases]. / Morbidité maternelle liée à l'accouchement à propos de 124 observations.

In a prospective survey, the authors related 124 cases of maternal traumatic lesions during a child birth. They were apper lesions in 13% of uterine rupture, and lower lesions in 87% cervical vaginal and vulvoperineal ruptures). Adolescent primiparas were the most concerned with an incidence of 9.12% followed by the greater number of multiparas 8.24%. Age, parity, badly or unassisted deliveries were the main factors of risk. For the uterine rupture surgical intervention was preservative in 62% of cases. Suture has been essential in lower lesions. One maternal decease is registered, the foetal forecast is bad (14 foetal decease out of 16) in the uterine rupture. Morbidity was important: 64% in cicatricial perineum, 62% in cicatricial uterine, 37% in hysterectomy. In results, that all the cases of maternal traumatic lesions observed were avoidable. The authors recommended a better pregnancy and delivery care.

Patterns of reproduction among the Fang of Nsork (Equatorial Guinea): pregnancies, abortions and child spacing

Fang women are known to practice virtually no contraception but for them induced abortion is not an acceptable option. Their reproductive behaviour consequently is governed by the ability to conceive, spontaneous intrauterine mortality and child spacing (due to prolonged breast-feeding and sexual abstinence). In a sample of 587 women from one hospital and one clinic in Nsork, there was a positive correlation between maternal age and the number of pregnancies, resulting in a mean of 5.52 pregnancies per female and one child born every 2.5 years. The reported spontaneous abortion rate was 28.6 per cent

Effect of repeated targeted mass treatment with praziquantel on the prevalence, intensity of infection and morbidity due to Schistosoma intercalatum in an urban community in equatorial Guinea.

A longitudinal community-based study was carried out in order to evaluate the impact of repeated selective population chemotherapy with praziquantel on the epidemiology of an urban focus of Schistosoma intercalatum in the city of Bata, capital of the Continental Region of Equatorial Guinea. Three surveys were undertaken in January of 1988, 1989 and 1990, determining parasitological prevalence, intensity of infection and morbidity and applying repeated targeted mass treatment. One dose of praziquantel (40 mg/kg body weight) was given one week after treatment with mebendazole (100 mg every 12 hours for 3 days). A reduction of the overall prevalence by S. intercalatum of 69.9% and 79.3% in the first and second year respectively was found. Persons showing high parasite burden suffered a reduction of 95.7%. The cure rate (no more eggs in stool) was between 90% and 98.9%. A significant decrease of signs and symptoms was observed. No important side effects were detected. This study shows the positive action of praziquantel in reducing prevalence, intensity of infection and morbidity due to S. intercalatum, above all in the case of a high human population participation response. Cure rates obtained being similar to the ones observed using the same drug in Schistosoma mansoni and Schistosoma haematobium.

Endemic human paragonimiasis in Equatorial Guinea. Detection of the existence of endemic human paragonimiasis in Equatorial Guinea as a result of an integrated sanitary programme.

Between February and April 1990 the first five cases of human paragonimiasis, tentatively due to Paragonimus africanus, have been detected in Equatorial Guinea, thanks to the normal activities of the National Schistosomiasis Project and its coordination with the National Tuberculosis Project.