Profiles of microorganisms isolated from neonates' blood cultures, incubators, cradles, ventilators, washbasins, and health-workers of Libreville University Hospital Neonatal Service: focus on infection prevention and control measures.

BACKGROUND: Nosocomial infection outbreaks in neonatal services are a serious healthcare concern in both developed and developing countries, but few studies have been conducted in sub-Saharan Africa. OBJECTIVE: This study explored the etiology of septicemia in neonates and associated patterns of antimicrobial susceptibility in Gabon. METHODS: We analyzed cultures from neonates' blood and swabs from medical personnel and equipment located in the neonatology service. RESULTS: Sixty-eight microorganisms were isolated from the medical personnel and equipment; 46 microorganisms were isolated from neonates' blood culture. Klebsiella pneumoniae spp pneumoniae was the most common bacteria found in both (30.6% and 26.9%, respectively). All Klebsiella pneumoniae spp pneumonia isolates were resistant to amoxicillin with clavulanic acid, gentamycin resistance ranged from 93% to 100%, and cephalosporin resistance ranged from 33.3% to 47%. CONCLUSIONS: Awareness of the etiology, prevalence, and outcome of nosocomial infection is the first and most important step to appropriate interventions.

Circulating anti-SARS-CoV-2 nucleocapsid (N)-protein antibodies and anti-SARS-CoV-2 spike (S)-protein antibodies in an African setting: herd immunity, not there yet!

OBJECTIVE: Herd immunity is achieved when in a population, immune individuals are in a sufficiently large proportion. Neutralizing antibodies specific to SARS-CoV-2 that are produced following infection or vaccination are critical for controlling the spread of COVID-19. The objective of the present work was to investigate the rate of SARS-CoV-2 natural immunization in Gabonese. RESULTS: One thousand, four hundred and ninety two people were enrolled. The overall prevalence of anti-SARS-CoV-2 antibodies was 36.2%. Moreover, 76.4% of people who developed a humoral response to SARS-CoV-2 produced both anti-SARS-CoV-2 N-protein antibodies and anti-SARS-CoV-2 S-protein antibodies, which correspond to 27.7% of the total population. In infants (0-9 month), children (1-17 years) and adults, the prevalence of anti-SARS-CoV-2 antibodies was relatively the same, between 33 and 37% (any antibody types) and between 25 and 28.6% (neutralizing antibodies). In this African context, one-third (1/3) of the screened population was exposed to SARS-CoV-2 and three-quarter (3/4) of those exposed individuals developed neutralizing antibodies against SARS-CoV-2. This data suggest that herd immunity is not yet to be achieved in Gabon.

Altered Toll-Like Receptor-4 Response to Lipopolysaccharides in Infants Exposed to HIV-1 and Its Preventive Therapy.

Pathogen sensing and recognition through pattern recognition receptors, and subsequent production of pro-inflammatory cytokines, is the cornerstone of the innate immune system. Despite the fact that HIV-exposed uninfected (HEU) infants are prone to serious bacterial infections, no study has focused on the functionality of their bacteria recognition system. This is the first study to investigate baseline levels of three critically important immune response molecules in this population: complement component (C)-3, toll-like receptor (TLR)-4, and C-reactive protein (CRP). We enrolled 16 HEU and 6 HIV-unexposed (HU) infants. TLR4 function was investigated by stimulating whole blood with increasing concentrations of TLR4-agonist ultrapure lipopolysaccharides. TLR4/TLR4-agonist dose response were assessed by measuring IL-6 secretion. Complement C3 and CRP were measured by photo spectrometry. Data showed no significant differences in baseline concentration of CRP between HEU and HU infants. Complement C3 was significantly higher in HEU infants than HU infants. TLR4 anergy was observed in 7 of 12 HEU infants, whereas the rest of HEU infants (n = 4) and the control HU infants tested (n = 3) showed responsive TLR4. None of the HEU infants investigated in this study had severe infections in the year after their birth. In conclusion, TLR4 anergy can occur in HEU infants without necessarily translating to increased vulnerability to infectious diseases.