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Re-examination, using molecular tools, of the diversity of haemosporidian parasites (among which the agents of human malaria are the best known) has generally led to rearrangements of traditional classifications. In this study, we explored the diversity of haemosporidian parasites infecting vertebrate species (particularly mammals, birds and reptiles) living in the forests of Gabon (Central Africa), by analyzing a collection of 492 bushmeat samples. We found that samples from five mammalian species (four duiker and one pangolin species), one bird and one turtle species were infected by haemosporidian parasites. In duikers (from which most of the infected specimens were obtained), we demonstrated the existence of at least two distinct parasite lineages related to Polychromophilus species (i.e., bat haemosporidian parasites) and to sauropsid Plasmodium (from birds and lizards). Molecular screening of sylvatic mosquitoes captured during a longitudinal survey revealed the presence of these haemosporidian parasite lineages also in several Anopheles species, suggesting a potential role in their transmission. Our results show that, differently from what was previously thought, several independent clades of haemosporidian parasites (family Plasmodiidae) infect mammals and are transmitted by anopheline mosquitoes.

Integrated data on hepatitis B virus (HBV) patterns, HBV genotypes and mutations are lacking in human immunodeficiency virus type 1 (HIV-1) co-infected patients from Africa. This survey was conducted in 2010-2013 among 762 HIV-1-positive adults from Gabon who were predominantly treated with 3TC-based antiretroviral treatment. HBV patterns were identified using immunoassays detecting total antibody to hepatitis B core antigen (HBcAb), hepatitis B surface antigen (HBsAg), IgM HBcAb, hepatitis B e antigen (HBeAg), antibody to HBsAg (HBsAb) and an in-house real-time PCR test for HBV DNA quantification. Occult hepatitis B (OBI) was defined by the presence of isolated anti-HBc with detectable serum HBV DNA. HBV genotypes and HBV mutations were analyzed by PCR-direct sequencing method. Seventy-one (9.3%) patients tested positive for HBsAg, including one with acute hepatitis B (0.1%; 95% CI, 0.0%-0.2%), nine with HBeAg-positive chronic hepatitis B (CHB) (1.2%; 95% CI, 0.6%-2.2%), 16 with HBeAg-negative CHB (2.1%; 95% CI, 1.2%-3.3%) and 45 inactive HBV carriers (5.9%; 95% CI, 4.4%-7.8%). Sixty-one (8.0%; 95% CI, 6.2%-10.1%) patients showed OBI. Treated patients showed similar HBV DNA levels to those obtained in untreated patients, regardless of HBV patterns. Around 15.0% of OBI patients showed high (>1,000 UI/mL) viremia. The mutation M204V/I conferring resistance to 3TC was more common in HBV/A (47.4%) than in HBV/E isolates (0%) (P = .04). Our findings encouraged clinicians to promote HBV vaccination in patients with no exposure to HBV and to switch 3TC to universal TDF in those with CHB.

Background: Apart from outbreak reports, little is known about the endemicity of dengue and chikungunya virus in African countries. We investigated serum samples collected in Gabon before major outbreaks in 2007 and 2010 in order to identify pre-outbreak-circulation of both viruses., Methods: Serum samples from Gabonese infants (162) were analyzed at 3, 9, 15 and 30 months of age by commercial ELISA for dengue and chikungunya IgG-antibodies. If samples were positive medical records of participants were analyzed for symptoms concordant with dengue and chikungunya infections during the time period of assumed seroconversion., Results: IgG-antibodies against dengue were found in 12.3%, and IgG-antibodies against chikungunya in 0.6% of infants tested. Using the four measuring time points, we estimated corresponding incidences of 51/1.000 person-years and 2.5/1.000 person-years, respectively. Symptoms in positive-tested infants were mostly non-specific., Conclusion: Seropositivity suggests that both viruses circulated before the well-noticed outbreaks. Clinical diagnosis of dengue and chikungunya is difficult especially in infants, underscoring the need for accurate and reliable diagnostic tests as well as awareness of medical personnel., Clinical Trials Registration: NCT00167843., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Recently, major progress has been made in controlling malaria in Africa. However, in Gabon, little information is available on the role of malaria in childhood febrile syndromes, the use and efficacy of preventive measures, and Plasmodium species distribution. Here, we characterized malaria in febrile children in Franceville, Gabon through a cross-sectional study at the pediatric unit of the Franceville Regional Hospital. We registered 940 febrile children. Their general condition was markedly altered in 11.7% of cases (n = 89/760); among them 19 (21.4%) had a severely altered condition. Malaria was the second most frequent etiology (22.0%; n = 162/738), after respiratory tract infections (37.3%; n = 275/738). Children with malaria (63 ± 39 months) were older than children without malaria (40 ± 37 months) (p = 0.0013). Hemoglobin, red blood cell, white blood cell, and platelet values were lower in children with malaria than in those without malaria (p < 0.0001). Anemia was the most common feature of severe malaria (70.6%; n = 12/17), followed by neurological involvement (23.5%; n = 4/17). The prevalence of malaria was significantly higher in children older than 60 months than in younger children (40% vs. 15.5%; p < 0.0001). Plasmodium falciparum accounted for 97.5% of cases (158/162), followed by Plasmodium malariae (2.5%; n = 4/162). Bed net use was high (74.4%; n = 697/936) and contributed to malaria prevention (p = 0.001). Good basic knowledge of malaria also had a preventive effect (p < 0.0001). The prevalence of malaria in children in Franceville did not decrease significantly from 2009 to 2012, remaining at about 20%, highlighting that preventive measures should be reinforced., (© S. Maghendji-Nzondo et al., published by EDP Sciences, 2016.)

Neonatal invasive disease due to Streptococcus agalactiae is life threatening and preventive strategies suitable for resource limited settings are urgently needed. Protective coverage of vaccine candidates based on capsular epitopes will relate to local epidemiology of S. agalactiae serotypes and successful management of critical infections depends on timely therapy with effective antibiotics. This is the first report on serotype distribution and antimicrobial susceptibility of S. agalactiae in pregnant women from a Central African region. Serotypes V, III, and Ib accounted for 88/109 (81%) serotypes and all isolates were susceptible to penicillin and clindamycin while 13% showed intermediate susceptibility to erythromycin.

Objective: Many researchers continue to believe that urbanization is a major contributor to diabetes. We seek to demonstrate that the social status associated with urbanization has an impact on the prevalence of diabetes in Libreville, Gabon in sub-Saharan Africa., Methods: Our study was conducted in Libreville, the capital of Gabon; the city has a population of 397,000. Our study analyzed data from the registries of patients hospitalized in 2013 in the main diabetes center in Libreville., Results: The results revealed that, for 2013, 798 patients were hospitalized with diabetes at a prevalence of .2%. We found differences (P<.05) between women (423) and men (375). Mean age for women was 52.02 years and 48.88 years for men. The number of existing cases hospitalized was significantly more than new cases. All levels of society were represented in our study: students (42); military (36); administratives (99); technicians (180); unemployed (295); and retired (146). The results showed that the unemployed (36%), particularly women (29.40%) are most affected by diabetes., Conclusions: Our results show the impact of social status on the increase of diabetes in Libreville. We found that urbanization, associated with insecurity especially in women, had an effect on the prevalence of diabetes in Libreville. These results indicate that, apart from the non-modifiable factors (age, race, ethnicity), insecurity is a modifiable factor that should be taken into account.

Background: Like other tropical African countries, Gabon is afflicted by many parasitic diseases, including filariases such as loiasis and mansonellosis. This study aimed to assess the prevalence of these two filarial diseases in febrile and afebrile children using quantitative real-time PCR and standard PCR assays coupled with sequencing., Methodology/principal Findings: DNA from blood specimens of 1,418 Gabonese children (1,258 febrile and 160 afebrile) were analyzed. Overall, filarial DNA was detected in 95 (6.7%) children, including 67 positive for M. perstans (4.7%), which was the most common. M. perstans was detected in 61/1,258 febrile children (4.8%) and 6/160 afebrile children (3.8%, P = 0.6). Its prevalence increased statistically with age: 3.5%, 7.7% and 10.6% in children aged ≤ 5, 6-10 and 11-15 years, respectively. M. perstans prevalence was significantly higher in Koulamoutou and Lastourville (12% and 10.5%, respectively) than in Franceville and Fougamou (2.6% and 2.4%, respectively). Loa loa was detected in seven febrile children including one co-infection with M. perstans. Finally, 21 filarial DNA positive were negative for M. perstans and Loa loa, but ITS sequencing could be performed for 12 and allowed the identification of a potential new species of Mansonella provisionally called "DEUX". Mansonella sp. "DEUX" was detected only in febrile children., Conclusions/significance: Further study should be performed to characterize Mansonella sp. "DEUX" and evaluate the clinical significance of mansonellosis in humans.

Background: There have been many reports on the population genetic structure of Plasmodium falciparum from different endemic regions especially sub-Saharan Africa. However, few studies have been performed on neglected populations, such as the Pygmy populations. In this study, the population genetic structure of P. falciparum was investigated in the Baka Pygmies of Gabon and compared to that observed in neighboring villages composed mostly of Bantu farmers., Methods: A total of 342 blood samples were collected from 170 Baka Pygmies and 172 Bantus in the north of Gabon (Woleu Ntem Province). Plasmodium infections were characterized by sequencing a portion of the parasite cytochrome b gene. Population genetic structure of P. falciparum in the different villages was analysed using microsatellite markers and genes coding for antigenic proteins (MSP1, MSP2, GLURP, and EBA-175)., Results: Overall, prevalence of P. falciparum was around 57 % and no significant difference of prevalence was observed between Pygmies and Bantus. No significant differences of population genetic structure of P. falciparum was found between Pygmy and Bantu people except for one antigen-coding gene, glurp, for which genetic data suggested the existence of a potentially disruptive selection acting on this gene in the two types of populations. The genetic structure of P. falciparum followed a pattern of isolation by distance at the scale of the study., Conclusion: The prevalence and genetic diversity of P. falciparum observed in Baka demonstrates a significant transmission of the parasite in this population, and some exchanges of parasites with Bantu neighbours. Despite that, some antigen-coding genes seem to have had a particular evolutionary trajectory in certain Pygmy populations due to specific local human and/or mosquito characteristics.

Rickettsia felis has been reported to be a cause of fever in sub-Saharan Africa, but this association has been poorly evaluated in Gabon. We assessed the prevalence of this bacterium among children <15 years of age in 4 areas of Gabon; the locations were in urban, semiurban, and rural areas. DNA samples from 410 febrile children and 60 afebrile children were analyzed by quantitative PCR. Overall, the prevalence of R. felis among febrile and afebrile children was 10.2% (42/410 children) and 3.3% (2/60 children), respectively. Prevalence differed among febrile children living in areas that are urban (Franceville, 1.3% [1/77]), semiurban (Koulamoutou, 2.1% [3/141]), and rural (Lastourville, 11.2% [15/134]; Fougamou, 39.7% [23/58]). Furthermore, in a rural area (Fougamou), R. felis was significantly more prevalent in febrile (39.7% [23/58]) than afebrile children (5.0% [1/20]). Additional studies are needed to better understand the pathogenic role of R. felis in this part of the world.

Objectives: On the background of a high prevalence of HHV-8 infection in pre-pubertal Central African children, this study investigated the potential for in utero transmission of HHV-8., Patients: Gabonese pregnant women were invited to provide peripheral and cord blood samples for serological and PCR diagnostics of HHV-8 infection at delivery for this cross-sectional survey., Results: Out of 344 participants 120 (35%, 95% CI: 30-40%) were serologically positive for HHV-8. 31% (95% CI: 22-40%) of cord blood samples of seropositive women had detectable IgG antibodies. Among all seropositive participants HHV-8 was detected by PCR in one maternal peripheral blood sample at delivery (1%, 95% CI: 0.2-7%) and in none of cord blood samples. There was no association between demographic characteristics and infection status. Similarly, there was no difference in risk for premature delivery, low birth weight, and maternal anaemia in HHV-8 seropositive women., Discussion: These data suggest a high seroprevalence of HHV-8 infection in pregnant women, however viraemia at delivery does not commonly occur in Central Africa. Based on these observations it may be speculated that infection of children may occur more commonly either antepartum or later on in infancy and childhood., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The emergence of HIV-1 groups M, N, O, and P is the result of four independent cross-species transmissions between chimpanzees (cpz) and gorillas (gor) from central/south Cameroon and humans respectively. Although the first two SIVcpz were identified in wild-born captive chimpanzees in Gabon in 1989, no study has been conducted so far in wild chimpanzees in Gabon. To document the SIVcpz infection rate, genetic diversity, and routes of virus transmission, we analyzed 1458 faecal samples collected in 16 different locations across the country, and we conducted follow-up missions in two of them. We found 380 SIV antibody positive samples in 6 different locations in the north and northeast. We determined the number of individuals collected by microsatellite analysis and obtained an adjusted SIV prevalence of 39.45%. We performed parental analysis to investigate viral spread between and within communities and found that SIVs were epidemiologically linked and were transmitted by both horizontal and vertical routes. We amplified pol and gp41 fragments and obtained 57 new SIVcpzPtt strains from three sites. All strains, but one, clustered together within a specific phylogeographic clade. Given that these SIV positive samples have been collected nearby villages and that humans continue to encroach in ape's territories, the emergence of a new HIV in this area needs to be considered.

Purpose: HIV, bacterial sepsis, malaria, and tuberculosis are important causes of disease in Africa. We aimed to determine the impact of HIV on the presentation, causes and outcome of bacterial sepsis and other acute febrile illnesses in Gabon, Central Africa., Methods: We performed a prospective observational study in new adult admissions with fever or hypothermia (≥ 38 or <36 °C). Blood cultures, as well as HIV and malaria testing were performed in all patients., Results: We enrolled 382 patients, including 77 (20.2%) with HIV infection. Malaria was the most frequent diagnosis (n = 130, 34%), and was associated with a more severe presentation in HIV patients. Sepsis was also common (n = 107, 28%), including 29 (7.6%) patients with culture confirmed bacterial bloodstream infection. Bacterial bloodstream infections were more frequent in HIV patients, in particular with S. pneumoniae. Tuberculosis was observed in 29 (7.6%) patients, and was also more common in HIV patients. The majority of HIV patients was newly diagnosed, and only 15 (19.5%) were using combination antiretroviral therapy., Conclusions: Our findings illustrate the impact of HIV co-infection on the burden of sepsis, malaria and tuberculosis in Gabon, as well as the need to scale up HIV counseling, testing and treatment.

Clinical and epidemiological data from Central Africa on influenza A and parvovirus B19 infections are limited. We analyzed 162 blood samples of infants 3, 9, 15, and 30 months of age for IgG antibodies against both pathogens. Antibody responses were 0, 3.7%, 12.3%, and 20.4% against influenza A; and 1.2%, 2.5%, 3.1%, and 9.3% against parvovirus B19, respectively. Seropositivity rates were 89.5 (95% confidence interval [CI]: 59-120.1) and 38.2 (95% CI: 18.9-57.6)/1,000 person-years at risk for influenza A and parvovirus B19, respectively. Our data add to the understanding of the epidemiology of both conditions., (© The American Society of Tropical Medicine and Hygiene.)

Background: Helminth infections are a major public health problem, especially in the tropics. Infected individuals have an altered immune response with evidence that antibody response to vaccination is impaired. Hence, treatment of helminth infections before vaccination may be a simple intervention to improve vaccine immunogenicity. In the present study we investigated whether a single-dose antihelminthic treatment influences antibody responses to a seasonal influenza vaccine in primary school children living in Gabon, Central Africa., Methods: In this placebo-controlled double-blind trial conducted in Gabon the effect of a single-dose antihelminthic treatment with 400 mg albendazole versus a placebo one month prior to immunization with a seasonal influenza vaccine was investigated. Antiviral antibody titers against all three vaccine strains were assessed by haemagglutination inhibition (HI) test at baseline (Day 0; vaccination) and four weeks (Day 28) as well as 12 weeks (Day 84) following vaccination. Vaccine-specific memory B-cell response was measured at Day 0 and Day 84 by vaccine-specific Enzyme-linked Immunospot (ELISpot) assay. The trial is registered with the Pan African Clinical Trials Registry (PACTR) (PACTR201303000434188)., Results: 98 school children aged 6-10 years were randomly allocated to receive either antihelminthic treatment or placebo and were vaccinated one month after the treatment. The prevalence of helminths at baseline was 21%. Vaccine-specific HI titers against at least one of the three vaccine strains increased at Day 28 and Day 84 in all participants. HI titers against both influenza A strains as well as memory B-cell response were modestly higher in the antihelminthic treated group compared to the placebo group but the difference was not statistically significant. Total but not specific IgA was elevated in the antihelminthic treated group compared to the control group at Day 28., Conclusion: In our setting antihelminthic treatment had no significant effect on influenza vaccine immunogenicity. A trend towards better antiviral and vaccine immunogenicity in the antihelminthic treated group encourages studies to be conducted with alternative treatment schedules or in populations with a higher helminth burden.

Sickle cell disease (SCD) is a genetic disorder that poses a serious health threat in tropical Africa, which the World Health Organization has declared a public health priority. Its persistence in human populations has been attributed to the resistance it provides to Plasmodium falciparum malaria in its heterozygous state, called sickle cell trait (SCT). Because of migration, SCT is becoming common outside tropical countries: It is now the most important genetic disorder in France, affecting one birth for every 2,400, and one of the most common in the United States. We assess the strength of the association between SCT and malaria, using current data for both SCT and malaria infections. A total of 3,959 blood samples from 195 villages distributed over the entire Republic of Gabon were analyzed. Hemoglobin variants were identified by using HPLCy (HPLC). Infections by three species of Plasmodium were detected by PCR followed by sequencing of a 201-bp fragment of cytochrome b. An increase of 10% in P. falciparum malaria prevalence is associated with an increase by 4.3% of SCT carriers. An increase of 10 y of age is associated with an increase by 5.5% of SCT carriers. Sex is not associated with SCT. These strong associations show that malaria remains a selective factor in current human populations, despite the progress of medicine and the actions undertaken to fight this disease. Our results provide evidence that evolution is still present in humans, although this is sometimes questioned by scientific, political, or religious personalities.

We investigated the antimicrobial susceptibilities of mycoplasmas in Gabonese men and women. A total of 1,332 men and women were included in the study. Sperm, urine, ureteral or vaginal swabs were collected from the subjects. Mycoplasmas identification and antimicrobial susceptibility to azithromycin, clarithromycin, erythromycin, josamycin, pristinamycin, doxycycline, tetracycline, ofloxacin and ciprofloxacin were tested using the Mycoplasma IST 2 kit. 794 subjects were positive for Mycoplasma. Respectively, 1.6 % and 82.24 % of subjects were singly infected with M. hominis and Ureaplasma urealyticum and 15.87 % had a mixed infection. M. hominis isolates were resistant to erythromycin and had an intermediate (I) to resistant (R) profile to azithromycin and clarithromycin. 84.6 % of M. hominis strains were sensitive (S) to josamycin and pristinamycin. 30.8 % and 92.3 % of M. hominis strains were sensitive to tetracycline and doxycycline, respectively. 76.9 and 84.6 % of M. hominis isolates were sensitive to ciprofloxacin and ofloxacin, respectively. The sensitivity rates of U. urealyticum strains were 45.23 %, 47.7 %, 63.84 %, 90.8 % and 92 % for azithromycin, erythromycin, clarithromycin, pristinamycin and josamycin, respectively. U. urealyticum strains showed 62.2 % and 79.7 % sensitivity to tetracycline and doxycycline, respectively. The resistance rates to azithromycin, clarithromycin and erythromycin for samples with mixed infection were 72.8 %, 84.7 % and 85.6 %, respectively. Josamycin and pristinamycin were 81.5 % effective on samples with mixed infection. The sensitivity rates of samples with mixed infection to tetracycline, doxycycline, ciprofloxacin and ofloxacin were 32 %, 69.6 %, 8.9 % and 18.5 %, respectively. Sub-Saharan Africa needs to use antibiotics rationally, as falling to do so would compromise the management of infectious diseases.

Background: Foci of the HIV epidemic and helminthic infections largely overlap geographically. Treatment options for helminth infections are limited, and there is a paucity of drug-development research in this area. Limited evidence suggests that antiretroviral therapy (ART) reduces prevalence of helminth infections in HIV-infected individuals. We investigated whether ART exposure and cotrimoxazole preventive therapy (CTX-P) is associated with a reduced prevalence of helminth infections., Methodology and Principal Findings: This cross-sectional study was conducted at a primary HIV-clinic in Lambaréné, Gabon. HIV-infected adults who were ART-naïve or exposed to ART for at least 3 months submitted one blood sample and stool and urine samples on 3 consecutive days. Outcome was helminth infection with intestinal helminths, Schistosoma haematobium, Loa loa or Mansonella perstans. Multivariable logistic regression was used to assess associations between ART or CTX-P and helminth infection. In total, 408 patients were enrolled. Helminth infection was common (77/252 [30.5%]). Filarial infections were most prevalent (55/310 [17.7%]), followed by infection with intestinal helminths (35/296 [11.8%]) and S. haematobium (19/323 [5.9%]). Patients on CTX-P had a reduced risk of Loa loa microfilaremia (adjusted odds ratio (aOR) 0.47, 95% CI 0.23-0.97, P = 0.04), also in the subgroup of patients on ART (aOR 0.36, 95% CI 0.13-0.96, P = 0.04). There was no effect of ART exposure on helminth infection prevalence., Conclusions/significance: CTX-P use was associated with a decreased risk of Loa loa infection, suggesting an anthelminthic effect of antifolate drugs. No relation between ART use and helminth infections was established.

Prevalence of drug-resistant bacteria in wildlife can reveal the actual level of anthropological burden on the wildlife. In this study, we isolated two multiple drug-resistant strains, GG6-2 and GG6-1-1, from 27 fresh feces of wild western lowland gorillas in Moukalaba-Doudou National Park, Gabon. Isolates were identified as Achromobacter xylosoxidans and Providencia sp., respectively. Minimum inhibitory concentrations of the following 12 drugs-ampicillin (ABPC), cefazolin (CEZ), cefotaxime (CTX), streptomycin (SM), gentamicin (GM), kanamycin (KM), tetracycline (TC), nalidixic acid (NA), ciprofloxacin (CPFX), colistin (CL), chloramphenicol (CP) and trimethoprim (TMP)-were determined. Isolate GG6-2 was resistant to all antimicrobials tested and highly resistant to CTX, SM, TC, NA and TMP. Isolate GG6-1-1 was resistant to ABPC, CEZ, TC, CL, CP and TMP.

Objectives: This study aimed to determine the prevalence of enteric viruses causing gastroenteritis, and the circulating stains, in Gabonese children under five years old who visited health centers between March 2010 and June 2011., Methods: Stool specimens were collected and sent for analysis to CIRMF (Centre International de Recherches Médicales de Franceville). Stools were screened for six enteric viruses (rotavirus, adenovirus, norovirus I and II, sapovirus, human astrovirus) by means of a multiplex real-time reverse transcription polymerase chain reaction, and Rotavirus A, Adenovirus and Astrovirus were genotyped., Results: Among the 317 specimens analyzed, 193 (60.9%) were positive for at least one enteric virus. Rotavirus A (RVA) (27.1%) was the most frequently detected virus, followed by human Adenovirus (HAdV) (19.6%), Norovirus II (NoVs-II) (13.9%), Norovirus I (NoVs-I) (9.1%), Sapovirus (SaV) (9.5%) and human Astrovirus (HAstV) (6.3%). One-third of the 193 positive samples contained more than one virus. The most common Rotavirus A genotype was G6P[6]. Various HAdV serotypes were found. HAstV-1 was identified., Conclusions: These findings improve our knowledge of circulating enteric viruses in Gabon. The emergence of unusual G6P[6] strain of rotavirus A, predominant, suggested a particular epidemiological surveillance of circulating rotavirus strains during the introduction of vaccination in Gabon., (Copyright © 2015. Published by Elsevier Ltd.)

Malaria was considered as the main cause of fever in Africa. However, with the roll back malaria initiative, the causes of fever in Africa may change. This study aimed to evaluate the prevalence of bacteria and Plasmodium spp. in febrile and afebrile (controls) children from Franceville, Gabon. About 793 blood samples from febrile children and 100 from controls were analyzed using polymerase chain reaction (PCR) coupled with sequencing. Plasmodium spp. was the microorganism most detected in febrile (74.5%, 591/793) and controls (13%, 13/100), P < 0.0001. Its coinfection with bacteria was found only in febrile children (P = 0.0001). Staphylococcus aureus was the most prevalent bacterium in febrile children (2.8%, 22/793) and controls (3%, 3/100). Eight cases of Salmonella spp. (including two Salmonella enterica serovar Paratyphi) and two of Streptococcus pneumoniae were found only among febrile children. Borrelia spp. was found in 2 controls while Rickettsia felis was detected in 10 children (in 8 febriles and 2 afebriles). No DNA of other targeted microorganisms was detected. Plasmodium spp. remains prevalent while Salmonella spp., Staphylococcus aureus, and Streptococcus pneumoniae were common bacteria in Gabon. Two fastidious bacteria, Rickettsia felis and Borrelia spp., were found. Inclusion of controls should improve the understanding of the causes of fever in sub-Saharan Africa., (© The American Society of Tropical Medicine and Hygiene.)

Background: Cervical cancer is the commonest cancer and the leading cause of cancer mortality in women in Gabon. The age-standardized incidence of cervical cancer is 19.9 per 100 000 women and the mortality rate is 8.4 per 100 000. Various international studies have identified the lack of awareness and knowledge about cervical cancer as barriers to use preventive methods. This article assesses the awareness and knowledge about cervical cancer, Pap smear testing and its use and HPV among women living in Libreville, Gabon., Methods: This study was conducted in October 2014 in Libreville. A total of 452 women aged 16 years and above were recruited from different town locations. Logistic regression analysis was used to identify the effect of demographic characteristics on the level of knowledge about cervical cancer, Pap smear testing and HPV. Odds ratio and 95% confidence intervals were used to identify the strength of association. Associations were considered statistically significant at p < 0.05., Results: Of all the women interviewed, 91.6% (414/452) had heard about cervical cancer and only 27.9% (126/452) had heard of Pap smear test. Of these 126 women, only 65.1% (82/126) had done cervical cancer screening and 68.3% (56/82) on the suggestion of a doctor. The most common reason for not undergoing Pap smear testing was neglect (50%, 22/44) followed by lack of financial resources (13.6%, 6/44), fear of discovering a serious disease (13.6%, 6/44) and deeming it unimportant (13.6%, 6/44). Only 8% (40/452) of the participants had heard about HPV and their knowledge of HPV was fair. There is a very poor level of knowledge about cervical cancer among Gabonese women., Conclusion: This study demonstrates a very low level of knowledge about cervical cancer, Pap smear testing and HPV in a sample of Gabonese women. There is a critical need for Gabonese women to be informed about cervical cancer and the Pap smear test to improve the use of this preventive method. The implication of health staff and Gabonese media should be included as a centerpiece in the effort to inform the population in order to reduce the burden of cervical cancer in Gabon and save women lives.

Background: Shigella spp. dysentery is widespread in developing countries; the incidence is particularly high in children between 1-2 years of age. In sub-Saharan Africa, there is a paucity of epidemiological data on Shigella spp., with possible negative consequences for recognition and correct treatment choice for this life-threatening bacterial infection. We therefore characterized Shigella spp. isolates from Gabon., Methods: The antimicrobial resistance, virulence factors, genotypes and mobile genetic elements of Shigella isolates (29 S. flexneri; 5 S. boydii; 3 S. sonnei) from a retrospective strain collection were analyzed., Results: High resistance rates were found for gentamicin and tetracycline (100%, 37/37), cotrimoxazole (92%, 34/37) and ampicillin (84%, 31/37). All isolate harbored ial and ipaH; no isolate produced Shiga toxins (stx1/2); enterotoxins (set1A/B) were only found in S. flexneri (n=19). Multilocus sequence types (MLST) clustered with global clones. A high prevalence of atypical class 1 integrons harboring blaOXA30 and aadA1 were detected in S. flexneri, while all S. sonnei carried class 2 integrons., Conclusions: There is a strong link of Gabonese Shigella spp. isolates with pandemic lineages as they cluster with major global clones and frequently carry atypical class 1 integrons which are frequently reported in Shigella spp. from Asia., (© The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Group A streptococcus (GAS) and possibly other β-hemolytic streptococci (BHS) account for a considerable morbidity and mortality burden in African populations; however, disproportionately little is known about the epidemiology of BHS in sub-Saharan Africa. This study assessed the prevalence of GAS, group G streptococcus (GGS) and group C streptococcus (GCS) carriage and tonsillopharyngitis in a Central African population., Methods: A prospective cross-sectional study was performed to assess the prevalence of and risk factors for BHS carrier status and tonsillopharyngitis in children and adults in Gabon., Results: The overall BHS carrier prevalence was 135/1,005 (13.4%); carrier prevalence of GAS, GGS, and GCS was 58/1,005 (5.8%), 50/1,005 (5.0%), and 32/1,005 (3.2%), respectively. Streptococcal carriage was associated with school and pre-school age (adjusted OR 2.65, 95% CI 1.62-4.36, p = 0.0001 and 1.90, 95% CI 1.14-3.17, p = 0.0141, respectively). Participants residing in urban areas were less likely carriers (OR 0.52, p = 0.0001). The point-prevalence of BHS-positive tonsillopharyngitis was 1.0% (9/1,014) and 15.0% (6/40) in school children with sore throat., Conclusions: Non-GAS exceeded GAS throat carriage and tonsillopharyngitis suggesting a yet underestimated role of non-GAS streptococci in BHS diseases.

Background: Until 2009, the Laverania subgenus counted only two representatives: Plasmodium falciparum and Plasmodium reichenowi. The recent development of non-invasive methods allowed re-exploration of plasmodial diversity in African apes. Although a large number of great ape populations have now been studied regarding Plasmodium infections in Africa, there are still vast areas of their distribution that remained unexplored. Gabon constitutes an important part of the range of western central African great ape subspecies (Pan troglodytes troglodytes and Gorilla gorilla gorilla), but has not been studied so far. In the present study, the diversity of Plasmodium species circulating in great apes in Gabon was analysed., Methods: The analysis of 1,261 faecal samples from 791 chimpanzees and 470 gorillas collected from 24 sites all over Gabon was performed. Plasmodium infections were characterized by amplification and sequencing of a portion of the Plasmodium cytochrome b gene., Results: The analysis of the 1,261 samples revealed that at least six Plasmodium species circulate in great apes in Gabon (Plasmodium praefalciparum, Plasmodium gorA (syn Plasmodium adleri), Plasmodium gorB (syn Plasmodium blacklocki) in gorillas and Plasmodium gaboni, P. reichenowi and Plasmodium billcollinsi in chimpanzees). No new phylogenetic lineages were discovered. The average infection rate was 21.3% for gorillas and 15.4% for chimpanzees. A logistic regression showed that the probability of infection was significantly dependent on the freshness of the droppings but not of the host species or of the average pluviometry of the months of collection.

Background: The morbidity of malaria has steady declined in the urban regions of Gabon between 2000 and 2008, but caution should be exercised before generalizing this trend to the whole country because this finding has not been systematically confirmed in remote rural provinces., Methods: We conducted a retrospective survey using data on malaria cases recorded in North Eastern Gabon between 2006 and 2013 at health facilities in Makokou. Malaria data were analyzed, and associations with annual variations and patient age were assessed., Results: A global increase in clinical and confirmed malaria cases was observed over the study period. The rate of infection was significantly higher in children aged between 0 to 4 years than in children of 5 years and above, and in adults. Contrary to prior observations in urban and semi-urban areas of Gabon, malaria burden remained mostly unchanged or even increased in Makokou in the Ogooué-Ivindo province during these last 8 years., Conclusions: The persistence of Plasmodium falciparum pockets of sustained malaria transmission in rural Gabon may be related to an inadequate coverage of key interventions, to poor treatment seeking behavior and/or to a decline efficacy of treatments. Our results highlight the need to better adapt malaria control strategies to local epidemiological contexts and to environmental constraints. Equitable delivery of health service to hard-to-reach populations constitutes a challenging issue for the health authorities of Gabon.

Objective: Given the magnitude of the HIV epidemic infection, many viral and human factors were analyzed, and the most decisive was the variant CCR5-Δ32. The presence of a low HIV prevalence (1.8%) in Gabon in the 1990s, compared to neighboring countries, represents a paradox that led us to search for viral and human genetic variants in this country. In this study, only variants of coreceptors and chemokines were investigated., Methods: Variants of the coding region of the CCR5 gene were analyzed by denaturing gradient gel electrophoresis, and then variants of SDF1 and CCR2b were determined by polymerase chain reaction-restriction fragment length polymorphism., Results: Four rare variants of the CCR5 coreceptor were found, while CCR5-Δ32 and CCR5m303 variants were not found. No association with CCR2b-V64I (17%) and SDF1-3'A (2%) variants was determined in relation to HIV-1 infection in Gabonese patients., Conclusion: The paradox of HIV seroprevalence in Gabon, which ended in the 2000s, was not caused by human genetic variants but rather by environmental factors., (© 2015 S. Karger AG, Basel.)

We assessed Plasmodium (P.) falciparum allelic diversity based on clinical severity and age. The study was conducted from 2011 to 2012 in Libreville, Gabon where malaria prevalence was 24.5%. The polymorphism of the merozoite surface protein-1 (msp1) locus was analyzed in isolates from patients with complicated and uncomplicated malaria. Blood was collected on filter paper. After DNA extraction, genotyping of the msp1 gene was performed using nested PCR. The K1, Ro33, and Mad20 allelic families were detected in 71 (63%), 64 (57%), and 38 (34%) of the 112 analyzed samples, respectively. Overall, 17 K1 and 11 Mad20 alleles were detected. There was no association between msp1 allelic families and age. Mad20 allelic diversity increased with the severity of malaria. The number of K1 and Mad20 alleles decreased with age. The multiplicity of infection (MOI) was 1-6 genotypes and the complexity of infection (COI) 1.8 ± 1. The COI differed based on age: it was 1.9 (±1.1) in the isolates from adults, 1.8 (±1.1) in those from 0-5 year-old children, whereas it tended to be lower (1.6 ± 0.8) in those from 6-15 year-old children. Extensive genetic diversity is found in P. falciparum strains circulating in Libreville. The number of specific msp1 alleles increased with clinical severity, suggesting an association between the diversity and the severity of malaria., (© M.K. Bouyou-Akotet et al., published by EDP Sciences, 2015.)

Burkholderia pseudomallei, an environmental gram-negative bacillus, is the causative agent of melioidosis and a bio-threat agent. Reports of B. pseudomallei isolation from soil and animals in East and West Africa suggest that melioidosis might be more widely distributed than previously thought. Because it has been found in equatorial areas with tropical climates, we hypothesized that B. pseudomallei could exist in Gabon. During 2012-2013, we conducted a seroprevalance study in which we set up microbiology facilities at a large clinical referral center and prospectively screened all febrile patients by conducting blood cultures and testing for B. pseudomallei and related species; we also determined whether B. pseudomallei could be isolated from soil. We discovered a novel B. pseudomallei sequence type that caused lethal septic shock and identified B. pseudomallei and B. thailandensis in the environment. Our data suggest that melioidosis is emerging in Central Africa but is unrecognized because of the lack of diagnostic microbiology facilities.

The genus Anopheles includes mosquito vectors of human malaria and arboviruses. In sub-Saharan Africa, the anopheline fauna is rich of nearly 150 species, few of which are anthropophilic and capable of transmitting pathogens to humans. Some of the remaining species are found in forests far from human environments and are vectors of wildlife pathogens. The diversity and the biology of these species have yet to be fully described. As a contribution to furthering knowledge of sylvan Anophelinae, using morphological and molecular tools we describe a new Anopheles species collected in Gabon (Central Africa), which we have named Anopheles gabonensis n. sp. We also molecularly screened this species to detect infections by Plasmodium parasites. The results showed the species to have been infected by Plasmodium vinckei, a rodent parasite. We discuss the role of An. gabonensis n. sp. in the transmission of P. vinckei in the rainforest areas of Central Africa and its potential to transfer pathogens to humans., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Studies showed that chloroquine resistance may revert to sensitivity after its withdrawal mainly detected by a significant decrease of Plasmodium falciparum pfcrt 76T and pfmdr1 86Y alleles. Besides, self-medication is considered as a key factor of antimalarial drug resistance expansion. Thus, pfcrt 76T and pfmdr1 86Y allele frequency and its relationship with antimalarial drug self-medication was analyzed in P. falciparum isolates collected in Gabon., Methods: Samples were collected from febrile children screened for P. falciparum infection in 2005 and 2008 at the regional hospital of Oyem. Self-use of antimalarial drugs before the day of consultation was recorded. Polymorphic codons 76 and 86 of pfcrt and pfmdr1 genes were analyzed by PCR-RFLP., Results: The frequency of pfcrt 76T mutant allele was greater than 70.0% in 2005 and 2008. Wild type isolates were 1.7-fold more prevalent in 2008. The prevalence of pfmdr1 86Y mutant allele was comparable between 2005 and 2008 (p=0.1); the proportion of wild type allele reached 20.5% in 2008. The frequency of wild type allele pfcrt K76 or pfmdr1 N86 was higher among patients without anti-malarial drug self-medication compared to those who used it., Conclusions: An increase of the frequency of P. falciparum wild type allele pfcrt 76K and pfmdr1 86N was observed within a short period after chloroquine withdrawal. The proportion of mutant genotypes is still high, mainly among patients using self-medication with antimalarial drugs., (© The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Tropheryma whipplei is the causative agent of Whipple's disease and has been detected in stools of asymptomatic carriers. Colonization has been associated with precarious hygienic conditions. There is a lack of knowledge about the epidemiology and transmission characteristics on a population level, so the aim of this study was to determine the overall and age-specific prevalence of T. whipplei and to identify risk factors for colonization. This molecular epidemiological survey was designed as a cross-sectional study in a rural community in Central African Gabon and inhabitants of the entire community were invited to participate. Overall prevalence assessed by real-time PCR and sequencing was 19.6% (95% CI 16-23.2%, n=91) in 465 stool samples provided by the study participants. Younger age groups showed a significantly higher prevalence of T. whipplei colonization ranging from 40.0% (95% CI 27.8-52.2) among the 0-4 year olds to 36.4% (95% CI 26.1-46.6) among children aged 5-10 years. Prevalence decreased in older age groups (p<0.001) from 12.6% (95% CI 5.8-19.4%; 11-20 years) to 9.7% (95% CI 5.7-13.6) among those older than 20. Risk factor analysis revealed young age, male sex, and number of people sharing a bed as factors associated with an increased risk for T. whipplei carriage. These results demonstrate that T. whipplei carriage is highly prevalent in this part of Africa. The high prevalence in early life and the analysis of risk factors suggest that transmission may peak during childhood facilitated through close person-to-person contacts., (© 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.)

Background: Chronic schistosome infections are associated with T-cell hyporesponsiveness and a strong regulatory network. Murine studies have shown that schistosome infections can induce regulatory CD1d(hi) B cells, which inhibit inflammatory responses. Here, we evaluated the influence of regulatory B cells (Bregs) on T-cell cytokines in vitro in human schistosomiasis., Methods: Gabonese young adults were recruited from areas where Schistosoma haematobium (S.h) infections were high or low endemic. The study participants were categorized as infected or uninfected from an high endemic area or uninfected from a low endemic (nonendemic) area. Their B cells were studied for Breg subset markers and cocultured with allogenic anti-CD3-stimulated CD4(+) T cells, followed by T-cell cytokine analysis., Results: A greater percentage of B cells from S. haematobium-infected donors expressed cytoplasmic interleukin 10 (IL-10) and membrane-bound latency-associated peptide/transforming growth factor β1, compared with uninfected donors. T cells produced less interferon γ, interleukin 4, and interleukin 17 upon coculture with B cells from schistosome-infected individuals only, while the conversion to CD25(hi)FoxP3(+) and the percentage of IL-10(+) T cells was enhanced. Interestingly, depletion of the prominent IL-10-producing B-cell subset, CD1d(hi) cells, resulted in less IL-10(+) T cells in the S. haematobium-infected group, while levels of FoxP3(+) regulatory T cells remained unaffected., Conclusions: Schistosomes can induce functional Bregs in humans that may be instrumental in general T-cell hyporesponsiveness and may contribute to the increased regulatory milieu found in schistosomiasis., (© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

The department of internal medicine of the military hospital of Gabon managed 92 cases of upper gastrointestinal bleeding from April 2009 to November 2011. The frequency of these hemorrhages in the department was 8.2%; they occurred most often in adults aged 30-40 years and 50-60 years, and mainly men (74%). Erosive-ulcerative lesions (65.2%) were the leading causes of hemorrhage, followed by esophageal varices (15.2%). These results underline the importance of preventive measures for the control of this bleeding.

Background: Haemolytic conditions may contribute to disease pathogenesis and severe clinical manifestations through the liberation of free haemoglobin (Hb) and production of toxic free haem. Thus, free Hb and haem should be associated with altered MetHb and COHb levels in malaria as in other conditions., Methods: This study comprises data collected at three different sites: (i) a retrospective analysis of the first arterial blood gas result (ABGS) of any patient during 2010 at the University Hospital in Lisbon; (ii) a retrospective analysis of ABGS from patients with severe malaria admitted to the intensive care unit in Berlin, Germany; and (iii) a prospective study of non-invasive MetHb measurements in children with and without malaria in Lambaréné, Gabon., Results: In Lisbon, the mean MetHb level was 1.4% (SD: 0.5) in a total of 17,834 ABGS. Only 11 of 98 samples with a MetHb level of >3.0 referred to infections. COHb levels showed no particular association with clinical conditions, including sepsis. In 13 patients with severe malaria in Berlin, the mean MetHb levels on admission was 1.29%, with 1.36% for cerebral malaria and 1.14% for non-cerebral malaria (P > 0.05). All COHb measurements were below 2.3%. In Lambaréné, Gabon, 132 healthy children had a mean MetHb level of 1.57%, as compared to 150 children with malaria, with a value of 1.77% and 2.05% in uncomplicated and complicated cases, respectively (P < 0.01)., Conclusions: The data appears consistent with the methaemoglobin/haem hypothesis in malaria and sepsis pathogenesis. However, although MetHb was significantly different between healthy controls and children with malaria in Africa, the difference was rather small, also when compared to previous studies. Still, non-invasive bedside MetHb testing may warrant further evaluation as it could be a simple adjuvant tool for prognosis in resource poor settings.

Background: Surveillance of influenza-like illness (ILI) in Central Africa began only recently, and few data are therefore available on the circulation of influenza virus and other respiratory viruses. In Gabon, a Central African country, we established a surveillance network in four major towns in order to analyze cases of ILI among patients who visited health centers between March 2010 and June 2011, and to determine the viral etiology., Methods: Nasal swabs were sent for analysis to the Centre International de Recherches Médicales de Franceville, where they were screened for 17 respiratory viruses in a multiplex real-time reverse transcription polymerase chain reaction for all pathogens according the following pairs: adenovirus/parainfluenza virus 4, respiratory syncytial virus/human metapneumovirus, parainfluenza virus 1/parainfluenza virus 2, pandemic influenza virus A/seasonal influenza virus A (H1N1, H3N2)/seasonal influenza virus B, human coronaviruses 229E/OC43, human coronaviruses NL63/HKU1, rhinovirus/human parechovirus, and enterovirus/parainfluenza virus 3., Results: We analyzed a total of 1041 specimens, of which 639 (61%) were positive for at least one virus. Three-quarters of the patients were children under five years old. We therefore focused on this age group, in which 68.1% of patients were positive for at least one virus. The most common viruses were adenoviruses (17.5%), followed by parainfluenza viruses (PIVs) 1-4 (16.8%), enteroviruses (EV) (14.7%), respiratory syncytial virus (RSV) (13.5%), and influenza virus (11.9%). The prevalence of some viruses was subject to geographic and seasonal variations. One-third of positive samples contained more than one virus., Conclusions: Like most studies in the world, the virus PIVs, EV, RSV, Influenza virus, HRV were predominant among children under five years old in Gabon. An exception is made for adenoviruses which have a high prevalence in our study. However adenoviruses can be detected in asymptomatic persons. These finding gave a better knowledge of the circulation and the seasonality of the viruses involved in ILI in Gabon.

Sickle Cell Disease (SCD) is an important cause of death in young children in Africa, which the World Health Organization has declared a public health priority. Although SCD has been studied at the continental scale and at the local scale, a picture of its distribution at the scale of an African country has never been given. The aim of this study is to provide such a picture for the Republic of Gabon, a country where precisely the epidemiology of SCD has been poorly investigated. To this effect, 4250 blood samples from persons older than 15 were collected between June 2005 and September 2008 in 210 randomly selected villages from the nine administrative provinces of Gabon. Two methods were used to screen Sickle Cell Trait (SCT) carriers: isoelectric focusing (IEF) and high-performance liquid chromatography (HPLC). SCT prevalence in Gabon was 21.1% (895/4249). SCT prevalence was significantly larger for the Bantu population (21.7%, n=860/3959) than for the Pygmy population (12.1%, n=35/290), (p=0.00013). In addition, the presence of Plasmodium sp. was assessed via thick blood examination. Age was positively associated with SCT prevalence (odds-ratio for an increase of 10 years in age=1.063, p=0.020). Sex was not associated with SCT prevalence. The study reveals the absence of homozygous sickle-cell patients, and marked differences in SCT prevalence between the Gabonese provinces, and also between population groups (Bantu vs Pygmy). These findings could be used by the public health authorities to allocate medical resources and target prevention campaigns., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Blood transfusions carry the risk of transmitting blood-borne infections. In contrast to the situation in the developed world, there is a limited number of studies examining this problem in sub-Saharan Africa. In this study we aimed to calculate the risks of acquiring human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infection from units of blood issued by the Gabonese Blood Transfusion Centre between 2009 and 2011., Materials and Methods: All the donations were tested for infectious diseases and the seroconversion incidence rates of HIV, HBV and HCV were calculated. The residual risk of transfusion-associated transmission for each virus was calculated by multiplying the seroconversion rates by the window period expressed in fractions of a year., Results: The risks of becoming infected with HIV, HCV, and HBV in subjects receiving units of blood from the Gabonese Blood Transfusion Centre were 64.7, 207.94 and 534.53 per million donations, respectively., Conclusions: This study, which is the first to quantify the true risks of transfusion-transmitted infections in Gabon, reveals and confirms the need to reinforce preventative and screening strategies to improve transfusion safety in sub-Saharan Africa.

Background: Parenteral artesunate is recommended as first-line therapy for severe malaria. While its efficacy is firmly established, data on safety are still incomplete. Delayed hemolysis has been described in hyperparasitemic nonimmune travelers, but it is unknown if African children are equally at risk., Methods: Children aged 6 to 120 months with severe malaria were followed up after treatment with parenteral artesunate in Lambaréné, Gabon, and Kumasi, Ghana. The primary outcome was incidence of delayed hemolysis on day 14., Results: In total, 72 children contributed complete data sets necessary for primary outcome assessment. Delayed hemolysis was detected in 5 children (7%), with 1 child reaching a nadir in hemoglobin of 2.8 g/dL. Patients with delayed hemolysis had higher parasite counts on admission (geometric mean parasite densities (GMPD) 306 968/µL vs 92 642/µL, P = .028) and were younger (median age: 24 months vs 43 months, P = .046) than the rest of the cohort. No correlation with sickle cell trait or glucose-6-phosphate-dehydrogenase deficiency was observed., Conclusions: Delayed hemolysis is a frequent and relevant complication in hyperparasitemic African children treated with parenteral artesunate for severe malaria. Physicians should be aware of this complication and consider prolonged follow-up., Clinical Trials Registration: Pan-African Clinical Trials Registry: PACTR201102000277177 (www.pactr.org)., (© The Author 2013. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) colonization and infection are increasingly being reported worldwide and are associated with severe illness. The vast majority of MRSA infections are skin and soft tissue infections, while invasive disease remains rare. In Western countries, the epidemiology of MRSA is well documented, but from Central Africa, reports on MRSA are very limited., Methods: Case presentation and review of the literature. The clinical features, epidemiology, and characteristics of MRSA in Central Africa, as well as the treatment options, are discussed. We present a case of severe invasive CA-MRSA infection with pneumonia, pericarditis, and bacteremia in a previously healthy young woman in Gabon. Several virulence factors, like Panton-Valentine leukocidin and type I arginine catabolic mobile element, may play a role in the ability of CA-MRSA to cause severe invasive infections. Based on studies from Gabon and Cameroon (no reports were available from other countries), we find that the prevalence of MRSA is relatively low in this region. Treatment depends primarily on local prevalence and resistance profile of MRSA combined with clinical characteristics., Conclusion: Severe invasive infection with CA-MRSA is a rare disease presentation in Central Africa, where this pathogen is still relatively uncommon. However, cases of MRSA may be complicated by the human immunodeficiency virus (HIV) and tuberculosis epidemics, and also the limited availability of effective antibiotics.

Background: Blood transfusion is a life-saving therapeutic act without alternative. Each blood transfusion carries the risk of blood-borne pathogens transmission. The present study, is the first establishing the usefulness of blood donors screening questionnaire in the setting of the Gabonese National Blood Transfusion Center., Study Design: Nine hundred and thirty-four blood donors aged between 18 and 48 years old were initially enrolled and submitted to physical examination (body-mass index and blood pressure). After physical examination 854 donors were judged fit for blood donation and were randomly distributed in two groups. The first group of donors did not take the screening questionnaire; whereas the second group went through the screening questionnaire. Both groups were then tested for human immunodeficiency virus, hepatitis B, hepatitis C and syphilis., Results: Data revealed a seroprevalence among the donors of 2.5%, 2.5%, 1.1%, and 3.3% for the human immunodeficiency virus, hepatitis B, hepatitis C and syphilis markers respectively. In the Gabonese setting, blood donors' screening questionnaire reduced respectively by 0.6%, 0.35% and 1.3% the proportion of hepatitis B, hepatitis C and treponema pallidum seroreactive donors being selected for donation. The questionnaire had no positive effect on discriminating human immunodeficiency virus positive donors., Conclusion: Blood donors' seroprevalence of blood-borne pathogens is relatively important in our setting. Blood donors' screening questionnaire reduced the proportion of hepatitis B, hepatitis C and syphilis seropositive blood donors. The questionnaire did not effectively discriminate human immunodeficiency virus-infected donor candidates., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

Staphylococcus aureus colonization is a risk factor for invasive disease. There is a need to understand S. aureus colonization in infancy as the burden of S. aureus infections in infants is high. We aimed to investigate the transmission of S. aureus between mothers and their newborns during the first year after delivery in an African setting. In a longitudinal cohort study, colonization of Gabonese mother-infant pairs was assessed at delivery and after 1, 9 and 12 months. Swabs were taken from mothers (nares, mammillae) and infants (nares and throat). Isolates were characterized and risk factors for colonization were assessed using a standardized questionnaire. We recruited 311 mothers and 318 infants including seven sets of twins. Maternal and infant colonization rates declined synchronously following a peak after 1 month at 40% (mothers) and 42% (infants). Maternal colonization was a risk factor for S. aureus carriage in infants. Based on spa typing, direct mother-to-infant transmission was evident in 5.6%. Of all methicillin-resistant isolates (n = 9), 44.4% were related to the USA300 clone; 56.7% (n = 261) of all S. aureus carried Panton-Valentine leukocidin encoding genes. Direct mother-to-infant transmission was rare and cannot explain the increase of carriage in infants within the first month. A transmission from external sources is likely and challenges the S. aureus infection control in newborns and infants in an African setting. The detection of USA300-related MRSA fuels the concern about the spread of this clone in Central Africa., (© 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.)

Background: Nosocomial infections pose substantial risk to patients receiving care in hospitals. In Africa, this problem is aggravated by inadequate infection control due to poor hygiene, resource and structural constraints, deficient surveillance data and lack of awareness regarding nosocomial infections. We carried out this study to determine the incidence and spectrum of nosocomial infections, pathogens and antibiotic resistance patterns in a tertiary regional hospital in Lambaréné, Gabon., Methods: This prospective case study was carried out over a period of six months at the Albert Schweitzer Hospital, Lambaréné, Gabon. All patients admitted to the departments of surgery, gynecology/obstetrics and internal medicine were screened daily for signs and symptoms of hospital-acquired infections., Results: A total of 2925 patients were screened out of which 46 nosocomial infections (1.6%) were diagnosed. These comprised 20 (44%) surgical-site infections, 12 (26%) urinary-tract infections, 9 (20%) bacteraemias and 5 (11%) other infections. High rates of nosocomial infections were found after hysterectomies (12%) and Caesarean sections (6%). Most frequent pathogens were Staphylococcus aureus and Escherichia coli. Eight (40%) of 20 identified E. coli and Klebsiella spp. strains were ESBL-producing organisms., Conclusion: The cumulative incidence of nosocomial infections in this study was low; however, the high rates of surgical site infections and multi-resistant pathogens necessitate urgent comprehensive interventions of infection control.

Objective: The purpose of this study was to (1) describe the distribution of Chlamydia trachomatis (CT) and Human Immunodeficiency Virus (HIV) cases across gender and age groups in Libreville (Gabon); (2) examine Gabonese Sexually Transmitted Infections (STIs)-related risk behaviour., Methods: The sampled population was people attending the "Laboratoire National de Santé Plublique". Between 2007 and 2011, 14 667 and 9 542 people respectively, were tested for CT and HIV infections. 1 854 of them were tested for both infections. We calculated CT and HIV rates across gender and age groups. Also analysed was the groups' contribution to the general CT and HIV epidemiology. STIs-related risk behaviours were assessed in 224 men and 795 women (between July 2011 and March 2013) who agreed and answered a questionnaire including questions on their marital status, number of sex partners, sexual practices, history of STIs, sex frequency and condom use., Results: Data showed a 24% dropped in the CT infection rate between 2007 and 2010, followed by a 14% increase in 2011. The HIV infection rates for the same period were between 15% and 16%. The risk of a CT-positive subject getting HIV is about 0.71 times the risk of a CT-negative subject. Young adult aged between 18 and 35 years old represented 65.2% of people who had STIs. 80% of women and 66% of men confessed to an inconsistent use of condoms. 11.6% of women and 48% of men declared having multiple sex partners. 61% of questioned women and 67% of men declared knowing their HIV status., Conclusions: In this Gabonese setting, the population-aged from 18 to 35 years is the most affected by STIs. Other matters of concern are the inconsistent use of protection and sex with non-spousal or non-life partners.

Mansonella (M.) perstans filariasis is widely found in Africa, including Gabon where Loa loa is also endemic. This study reports the total IgE titres according to different bioclinical forms of single or co-infection with L. loa and M. perstans in 138 patients and 20 healthy controls. The median parasite density was significantly higher in cases of loiasis. IgE titres were higher in patients with microscopic dual-infection and in the group of patients with occult loiasis plus M. perstans microfilaraemia (8425 [5292-20,679]KUI/L and 6304 [1045-10,326]KUI/L, respectively), compared to individuals with either microfilaraemic Loa loa (3368 [1414-7074]KUI/L) or Mansonella (4370 [1478-7334]KUI/L) single infections (p<0.01). IgE levels were positively correlated with M. perstans microfilaraemia (rho=0.27; p<0.01). Compared to single infections, dual M. perstans-L. loa infection induces very high total IgE titres. Studies correlating IgE titres and clinical symptoms are needed to confirm the involvement of this immunoglobulin in the pathological processes during filariasis., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Background: Chikungunya and dengue viruses emerged in Gabon in 2007, with large outbreaks primarily affecting the capital Libreville and several northern towns. Both viruses subsequently spread to the south-east of the country, with new outbreaks occurring in 2010. The mosquito species Aedes albopictus, that was known as a secondary vector for both viruses, recently invaded the country and was the primary vector involved in the Gabonese outbreaks. We conducted a retrospective study of human sera and mosquitoes collected in Gabon from 2007 to 2010, in order to identify other circulating arboviruses., Methodology/principal Findings: Sample collections, including 4312 sera from patients presenting with painful febrile disease, and 4665 mosquitoes belonging to 9 species, split into 247 pools (including 137 pools of Aedes albopictus), were screened with molecular biology methods. Five human sera and two Aedes albopictus pools, all sampled in an urban setting during the 2007 outbreak, were positive for the flavivirus Zika (ZIKV). The ratio of Aedes albopictus pools positive for ZIKV was similar to that positive for dengue virus during the concomitant dengue outbreak suggesting similar mosquito infection rates and, presumably, underlying a human ZIKV outbreak. ZIKV sequences from the envelope and NS3 genes were amplified from a human serum sample. Phylogenetic analysis placed the Gabonese ZIKV at a basal position in the African lineage, pointing to ancestral genetic diversification and spread., Conclusions/significance: We provide the first direct evidence of human ZIKV infections in Gabon, and its first occurrence in the Asian tiger mosquito, Aedes albopictus. These data reveal an unusual natural life cycle for this virus, occurring in an urban environment, and potentially representing a new emerging threat due to this novel association with a highly invasive vector whose geographic range is still expanding across the globe.

Central Africa is a region highly affected by the tuberculosis (TB) pandemic; however, data on local epidemiology are scarce. In the quest for gearing up towards tailored interventions, assessment of local baseline situations is mandatory. We conducted a retrospective study of 62 children registered in the TB register of a hospital in Lambaréné, Gabon. The evaluation revealed a discrepancy between the TB burden and the commitment to control TB. Extrapolation of the incidence suggests an unexpectedly high childhood TB burden, assuming that the official overall TB incidence is an underestimate of the true TB burden in Gabon.