There are a great number of beneficial commensal microorganisms constitutively colonizing the mucosal lining of the lungs. Alterations in the microbiota profile have been associated with several respiratory diseases such as pneumonia and allergies. Lung microbiota dysbiosis might play an important role in the pathogenic mechanisms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as well as elicit other opportunistic infections associated with coronavirus disease 2019 (COVID-19). With its increasing prevalence and morbidity, SARS-CoV-2 infection in pregnant mothers is inevitable. Recent evidence shows that angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) act as an entry receptor and viral spike priming protein, respectively, for SARS-CoV-2 infection. These receptor proteins are highly expressed in the maternal-fetal interface, including the placental trophoblast, suggesting the possibility of maternal–fetal transmission. In this review, we discuss the role of lung microbiota dysbiosis in respiratory diseases, with an emphasis on COVID-19 and the possible implications of SARS-CoV-2 infection on pregnancy outcome and neonatal health.

Introduction: Lassa fever is a viral haemorrhagic fever with non-specific symptoms that has shown an upward trend in Nigeria and other West African countries, which is depicted by high incidence and case fatality in recent years. There are different reports on the yearly case burden of Lassa fever from the Federal Ministry of Health in Nigeria, through the regulatory body – Nigeria Centre for Disease Control (NCDC). Being the epicentre of the disease, Lassa fever has been exported from Nigeria to both neighbouring and distant countries.Methods: The aim of this review was to carry out a retrospective analysis from January 2015 to 26 September 2021 of the weekly and yearly outbreak of Lassa fever in Nigeria based on selected publications. The focus was on timely diagnosis, treatment option, public health interventions and progress of clinical trials for vaccine candidates, and to identify proactive measures that can be sustained to curb periodic outbreaks. The review was done using percentages, cross-tabulation and graphical charts. Results: The predominant age group infected was 21 to 40 years with a male to female ratio of 1:0.8. A total of 3311 laboratory-confirmed Lassa fever cases out of 20,588 suspected cases were identified from 29 states. Edo, Ondo, Taraba, Ebonyi, Bauchi, Plateau and Nasarawa had yearly Lassa fever incidence over the time frame considered. Contact tracing was done on over 33,804 individuals with about 90% completing follow-up. Case fatality rate within the period ranged from 9.3% to 29.2%. There is a sharp decline in the epidemiological trend of Lassa fever in the yearly seasonal peaks from weeks 1 to 13 with about 75% reduction in incidence between 2020 and 2021. Conclusion: The effective management of Lassa fever needs the implementation of preventive methods, prompt laboratory diagnosis, timely treatment, provision of personal protective equipment, cross-border surveillance, contact tracing, community awareness and vector control in order to minimise spread.

Staphylococcus species are the predominant Gram-positive organisms obtained from blood culture samples. Its incidence in bloodstream infection among children and adults varies among. Staphylococcus aureus is regarded as pathogenic with high morbidity and mortality while coagulase-negative staphylococci (CoNS) are often regarded as a contaminant and not a true cause of bacteremia despite its rising occurrence. Predisposing factors of staphylococcal bacteremia include malnutrition, malaria, HIV/AIDS and nosocomial infections. Methicillin-resistance in Staphylococcus aureus and CoNS in bacteremia is associated with an increase in multidrug-resistant virulent strains when compared to methicillin-sensitive S. aureus or CoNS. The impact of coagulase-negative staphylococci in bacteremia is on the increase with marked clinical complications. However, this review summarizes the prevalence and epidemiology of S. aureus and CoNS in bacteremia based on research outcomes in Africa, Asia, Europe, and North America.

We sought to analyze the prevalence of neonatal sepsis based on eight selected articles published in 2016 and 2017 with details on the demographics, bacteria distribution, risk factors, antibacterial susceptibility and the rising isolation of Coagulase-negative staphylococci (CoNS) among other bacteria isolates. Early Onset Neonatal Sepsis (EONS) was prevalent in most of the studies than Late-Onset Neonatal Sepsis (LONS). The rate of CoNS isolation in neonatal blood cultures was significantly high with varying mortality, morbidity and methicillin-resistant CoNS observed. However, CoNS is still considered as a contaminant when the clinical course is not consistent with sepsis. The predominant species were Staphylococcus epidermidis, S. haemolyticus, S. hominis and S. capitis, which were being regarded as conditional pathogens or contaminants. Staphylococcus capitis NRCS-A clone was identified in 17 countries with marked multidrug resistance. High susceptibility of CoNS to linezolid and vancomycin were observed, except in S. capitis NRCS-A clone that showed treatment failure to aminoglycosides and vancomycin. Research on CoNS in neonatal sepsis will be a thriving area for years to come especially with its close association with hospital routine, assessing its pathogenic potential, the global spread of the multidrug-resistant NRCS-A clone of S. capitis and the introduction of vaccination opportunities. Adequate funding and collaboration of research effort will be required to address these key questions.

The clinical impact of Staphylococcus epidermidis in bacteremia remains controversial. The aim of this study is to determine the methicillin resistance and biofilm formation of S. epidermidis isolates. A total of 102 S. epidermidis blood culture isolates from children under five attending seven selected hospitals in north-central and northwest Nigeria within 2009 to 2016 were analyzed for methicillin resistance using cefoxitin disk agar diffusion test. Phenotypic biofilm formation and molecular detection of the intercellular adhesion locus (icaA) gene was performed by the quantitative Microtitre Plate (MTP) method and conventional Polymerase Chain Reaction (PCR) respectively. Seventy-four (72.5%) Methicillin-Resistant Staphylococcus epidermidis (MRSE) was observed while biofilm formation was detected in 20 (19.6%) S. epidermidis isolates. The icaA gene positive and negative S. epidermidis were 22.5% (23/102) and 77.5% (79/102) respectively. In correlating the biofilm formation using MTP method and icaA gene detection, 19.6% were biofilm producers and icaA positive while 2.9% carried the icaA gene but did not produce biofilm on the tissue culture plate. Out of the icaA positive S. epidermidis, 91.3% were MRSE while 69.6% were MRSE among the icaA negative strains. Methicillin-Resistant Staphylococcus epidermidis is common and the majority of the biofilm-producing strains were highly resistant to methicillin. This suggests a close association between biofilm-formation in S. epidermidis with increased methicillin resistance.