Stella Ifeanyi Smith

Nigerian Institute of Medical Research | NIMR · Department of Molecular Biology and Biotechnology

Antibiotic resistance in Helicobacter pylori is a factor preventing its successful eradication. Particularly in developing countries, resistance against commonly used antibiotics is widespread. Here, we present an epidemiological study from Nigeria with 111 isolates. We analyzed the associated disease outcome, and performed a detailed characterizat...

Helicobacter pylori (Hp) strains that carry the cag type IV secretion system (cag-T4SS) to inject the cytotoxin-associated antigen A (CagA) into host cells are associated with peptic ulcer disease and gastric adenocarcinoma. CagA translocation by Hp is mediated by β1 integrin interaction of the cag-T4SS. However, other cellular receptors or bacteri...

Salmonella infections in humans can range from self-limiting gastroenteritis typically associated with non-typhoidal Salmonella (NTS) to typhoidal fever, which can be life-threatening. Salmonellosis causes considerable morbidity and mortality in both humans and animals, and has a significant socioeconomic impact worldwide. In Africa, it is difficul...

The deployment of molecular biology techniques for diagnosis and research in Nigeria is faced with a number of challenges, including the cost of equipment and reagents coupled with the dearth of personnel skilled in the procedures and handling of equipment. Short molecular biology training workshops were conducted at the Nigerian Institute of Medic...

Aquatic environments, including their flora and fauna, are known reservoirs of pathogenic Vibrio species. This study aimed to determine the diversity and antimicrobial susceptibility of bacteria from water hyacinth (Eichornia crassipes) and surrounding waters in Lagos lagoons. Bacteria isolation, phenotypic, and genotypic analysis were conducted us...

This article aimed to review the current literature on the impact of continuous shedding of the COVID-19 virus in infected patients in relation to disease outcome variables and viral dynamics. Electronic databases PubMed, Google Scholar, and MedlinePlus were searched using relevant keywords, restricting the selection to thirty-two peer-reviewed art...

Background: Genetic determinants are known to promote antibiotic resistance through horizontal gene transfer. Methods: We molecularly characterized integrons, plasmid replicon types and metallo-β-lactamase-encoding genes of 38 Pseudomonas aeruginosa strains isolated from clinical samples. Results: The P. aeruginosa isolates displayed high resistanc...

Background Multidrug resistant bacterial pathogens employ different mechanisms in evading the action of antibiotics. Multidrug resistance is wide spread among strains of Escherichia coli implicated in several infections including urinary tract infections, gastrointestinal infections, meningitis and bacteraemia. Aim/Objective This study investigate...

ackground: Helicobacter pylori (H. pylori) infection is the most prevalent type of bacterial infection. Current guidelines from different regions of the world neglect specific African conditions and requirements. The African Helicobacter and Microbiota Study Group (AHMSG), founded in 2022, aims to create an Africa-specific consensus report reflecti...

Background Anthrax is a non-contagious zoonotic disease caused by the Gram-positive, spore-forming bacterium Bacillus anthracis. Infection is common in livestock and wild animals such as cattle, goats, sheep, camels, and antelopes. In humans, anthrax may occur after contact with contaminated carcasses or animal products like milk and meat. The best...

b> Background: Helicobacter pylori colonises 50% of the world population and is a causative agent of gastritis, peptic ulcer disease, mucosa associate lymphoid tissue lymphoma and gastric cancer. Summary: In Africa, the prevalence rate has been found to be the highest in comparison to other parts of the world. Despite its high prevalence there are...

Campylobacter infections and campylobacteriosis-associated post-infectious sequelae are a significant global health burden that needs to be addressed from a specific African perspective. We conducted a comprehensive literature search on NCBI PubMed to compile a comprehensive narrative review article on Campylobacter infections in Africa, focusing o...

Background and Aims: Staphylococcus aureus is one of the most important pathogens of public health concern and a leading cause of nosocomial infections. In this study, we evaluated the effect of routinely used disinfectants in hospitals for surface decontamination on biofilm-forming S. aureus. Materials and Methods: forty-eight S. aureus isolates w...

Approximately half of the world’s population is estimated to be infected with Helicobacter pylori [...]

Multidrug resistance and invasiveness of non-typhoidal Salmonella (NTS) serovars have in recent times brought to the fore the public health risk associated with salmonellosis. This study was aimed at profiling NTS serovars isolated from food animals and humans for their susceptibility to antibiotics and plasmid replicon types. Forty seven NTS serov...

Non-typhoidal Salmonella (NTS) infections occur globally with high morbidity and mortality. The public health challenge caused is exacerbated by increasing rate of antibiotic resistance and absence of NTS vaccine. In this study, we characterized the outer membrane protein C (OmpC) serovars isolated from different food animals and predicted antigeni...

Helicobacter pylori (H. pylori) infection is ubiquitous worldwide, with prevalence rates of greater than 70% in Africa. Symptomatic patients present with foregut gastrointestinal symptoms which can be readily diagnosed with standardized non-invasive or invasive tests. The biggest challenge , however, is in the management of this condition with risi...

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the w...

Monkeypox (mpox), is a disease from the Poxviridae family that can cause several serious medical issues. This mini-review sought to analyze the existing literature regarding the current mpox outbreak with a focus on the prevalence, diagnostics, and containment measures. Mpox cases have been reported to World Health Organization (WHO) from 85 Member...

Coronavirus disease 2019 (COVID-19) is an infectious disease with a wide range of respiratory and extrapulmonary symptoms, as well as gastrointestinal symptoms. Despite recent research linking gut microbiota to infectious diseases like influenza, minimal information is known about the gut microbiota’s function in COVID-19 pathogenesis. Studies sugg...

BACKGROUND: Escherichia coli (E. coli) serotypes have been implicated as etiological agents in the pathogenesis of diarrhea in children. The aim of this study was to investigate the prevalence, virulence and antibiotic resistance profile of serotypes of E. coli in children between 0 and 5 years with diarrhea in Lagos, Nigeria, the most populous cou...

The high rate of antibiotic resistance constitutes a global threat to the continuous use of these drugs, because of increasing treatment failures. The aim of this study was to survey antibiotic prescription practices of veterinarians and the possible contribution to antimicrobial resistance (AMR) and antimicrobial stewardship (AMS) in Nigeria durin...

This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms. Abstract Helicobact...

Since the pandemic began in China in December 2019, thousands of variants of SARS-CoV-2 have emerged globally since late 2020. The World Health Organization (WHO) defined the SARS-CoV-2 variant of concern (VOC) as a variant with increased transmissibility, virulence, and decreased response to available diagnostics, vaccines, and therapeutics. Areas...

BacKground: non-typhoidal Salmonella (nts) serovars are the major cause of Salmonella gastroenteritis which is usually self-limiting; however, this could result in invasive systemic infection in infants, the elderly and immune-compromised people most especially in sub-saharan Africa. The food chain plays a significant role in Salmonella infections...

Omicron, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant that is now spreading across the world, is the most altered version to emerge so far, with mutations comparable to changes reported in earlier variants of concern linked with increased transmissibility and partial resistance to vaccine-induced immunity. This article p...

Authors' contributions This work was carried out in collaboration among all authors. Authors SNE, FAY, WPN and RNN were involved in the conceptualization and design of this study. Authors FAY, WPN, NKK and JAK were involved with collection of samples collection and data on basic hygiene practices. Authors SNE, LMN and RNN supervised the study. Auth...

Background and Aims. Diarrheal diseases caused by bacterial pathogens are widespread and they result in morbidity and mortality of a lot of people yearly. The aim of this study was to assess the role of the environment, health workers and food handlers as reservoirs of Vibrio cholerae, and other diarrhea causing bacteria. Methods. Healthcare worker...

Objective Prompt diagnosis of Helicobacter pylori infection is essential for proper treatment and eradication of the pathogen because prolonged infection could lead to gastric cancer. Sensitive and cost effective diagnostic methods are key to guiding treatment options that will reduce mortality. This study was aimed at detecting H. pylori from biop...

Cholera caused by Vibrio cholerae remains endemic and recurrent in Nigeria resulting in morbidity and mortality on annual basis. Vibrio cholerae O1 and non-O1/O139 are reported causative agents of the disease outbreak in Nigeria and some of these strains circulating the country acquired multidrug resistance potential. Several factors including soci...

Cholera caused by Vibrio cholerae remains endemic and recurrent in Nigeria resulting in morbidity and mortality on annual basis. Vibrio cholerae O1 and non-O1/O139 are reported causative agents of the disease outbreak in Nigeria and some of these strains circulating the country acquired multidrug resistance potential. Several factors including soci...

Background: The burden of Helicobacter pylori infection (HPI) in Africa remains high with varying levels of prevalence among children and adults reported in different regions of the continent. Persistent and uneradicated HPI could result in gastric cancer, although less severe pathological outcomes have been reported among Africans – the so-called...

Keywords Africa · Diagnosis · Helicobacter pylori · Treatment · Guideline Abstract Background: The burden of Helicobacter pylori infection (HPI) in Africa remains high with varying levels of prevalence among children and adults reported in different regions of the continent. Persistent and uneradicated HPI could result in gastric cancer, although l...

., is an emerging, opportunistic pathogen that causes infections such as , meningitis and in neonates and infants, and can sometimes lead to death. There is zero tolerance for the presence of . all powdered infant formulae because of the high mortality rate (80%) associated with . . Three . (CS14, CS17 and CS124) isolated from PIF retailed in Niger...

The crime of rape is a global challenge in developed and developing countries. However, there is a surge in the rate of this crime in Africa particularly Nigeria. Majority of rape cases in Nigeria go unreported and this tend to encourage the crime to fester. Hence, this study is aimed at evaluating the reportage of rape by the print media in Nig...

Background: Biofilm formation by pathogens is of great clinical importance as it mediates persistence and resistance to antibiotics, hence posing difficulty in treatment and management of diseases. The aim of this study was to evaluate the biofilm forming potential of Staphylococcus aureus isolated from urine samples of females with urinary tract i...

Objective Staphylococcus saprophyticus is a Gram-positive bacterium implicated in urinary tract infections in sexually active women along with other bacteria. There is a special need to accurately isolate and identify this organism in clinical specimens in order to prevent misidentification in the laboratory. The present study was carried out to ev...

Background: Multidrug resistance efflux pumps and biofilm formation are mechanisms by which bacteria can evade the actions of many antimicrobials. Antibiotic resistant non-typhoidal Salmonella serovars have become wide spread causing infections that result in high morbidity and mortality globally. The aim of this study was to evaluate the efflux p...

Background Pseudomonas aeruginosa an opportunistic pathogen, is widely associated with nosocomial infections and exhibits resistance to multiple classes of antibiotics. The aim of this study was to determine the antibiotic resistance profile, biofilm formation and efflux pump activity of Pseudomonas strains isolated from clinical samples in Abeokut...

Objective: Nosocomial and community acquired multidrug resistant Klebsiella infections are wide spread resulting in high morbidity and mortality due to limited number of antibiotics treatment options. This study investigated efflux pump activity, biofilm forming potential and antibiotic susceptibility profile of Klebsiella spp. isolated from clini...

Background: Staphylococcus saprophyticus is a Gram-positive bacterium implicated in urinary tract infections in sexually active women along with other bacteria. There is a special need to accurately isolate and identify this organism in clinical specimens in order to prevent misidentification in the laboratory. The present study was carried out to...

Virulence factors and its expression is very important in the pathology of coagulase negative staphylococcal urinary tract infections. This study was carried out to determine the prevalence of virulence genes in Staphylococcus saprophyticus isolated from urine samples of patients diagnosed with urinary tract infections (UTIs) in government hospital...

The medicinal plant Spathodea campanulata P. Beauv. (Bignoniaceae) has been traditionally applied for the prevention and treatment of diseases of the kidney and urinary system, the skin, the gastrointestinal tract, and inflammation in general. The present work shows for the first time how chemical components from this plant inhibit Helicobacter pyl...

A multifaceted approach is needed in combating the COVID-19 pandemic which is getting protracted with increasing cases around the world. The role of the media in tackling pandemics have been established. However, data on the role of mass media reportage in the present COVID-19 pandemic is scarce. The aim of this study was to analyze mass media repo...

negative bacterium majorly causing peptic ulcers and gastric cancer in humans. The combinations of two or more antibiotics such as amoxicillin, clarithromycin, metronidazole or tetracycline with anti-secretory agents or bismuth have been used successfully for the treatment of H. pylori. AIM: Increasing antibiotic resistance has been a contributory...

The human gastrointestinal microbiota (GIM) is a complex and diverse ecosystem that consists of community of fungi, viruses, protists and majorly bacteria. The association of several human illnesses, such as inflammatory bowel disease, allergy, metabolic syndrome and cancers, have been linked directly or indirectly to compromise in the integrity of...

Helicobacter pylori is a gram-negative, spiral-shaped bacterial pathogen and the causative agent for gastritis, peptic ulcer disease and classified as a WHO class I carcinogen. While the prevalence of H. pylori infections in Africa is among the highest in the world, the incidence of gastric cancer is comparably low. Little is known about other symp...

BacKgroUnD: infections caused by Salmonella spp. remain an important public health threat especially in developing countries. in recent years, rapid emergence of antibiotics resistance has resulted in the inefficacy of available treatment options which has led to exponential increase in mortality and economic burden. the study aimed to screen Salmo...

The global evolution of antibiotic resistance has threatened the efficacy of available treatment options with ravaging impacts observed in developing countries. As a result, investigations into the prevalence of antibiotic resistance and the role of plasmids are crucial. In this study, we investigated the presence and distribution of blaTEM and gyr...

The medicinal plant Spathodea campanulata P. Beauv. (Bignoniaceae) has been traditionally applied for the prevention and treatment of diseases of the kidney and urinary system, the skin, the gastrointestinal tract, and inflammation in general. The present work shows for the first time how chemical components from this plant inhibit Helicobacter pyl...

Introduction: Helicobacter pylori is a principal cause of gastric cancer. The aim of this study was to determine the prevalence and contribution of duodenal ulcer promoting gene A (dupA), the plasticity region genes and sigma factors in relation to their pathological expression of H. pylori infections in the Nigerian population. Methodology: Pol...

Background: Helicobacter pylori (H. pylori) infection is common among humans and plays a major role in the etiology of peptic ulcer disease with significant morbidity in patients with HIV-1 on antiretroviral therapy. There are conflicting prevalence patterns of H. pylori in HIV-1 infected patients using various methods of detection. The noninvasive...

Outbreaks of Salmonellosis remain a major public health problem globally. This study determined the diversity and antibiotic resistance gene profile of Salmonella enterica serovars isolated from humans and food animals. Using standard methods, Salmonella spp. were isolated from fecal samples, profiled for antimicrobial susceptibility and resistance...

Infections caused by non-typhoidal Salmonella (NTS) are common around the world, with high morbidity and mortality rates recorded annually. Salmonella serovars harbor plasmids of various sizes which may play roles in antibiotic resistance and virulence. The aim of this study was to profile and determine the role of plasmids in ciprofloxacin resista...

Introduction Plants in the Cameroon Pharmacopoeia are used by the population as decoctions, infusions and are macerated to relieve digestive and gastric disorders. The aim of this study was to screen for the anti-Helicobacter pylori and anti-adhesion activities of various plant extracts from Cameroon. Methods Medicinal plants used for the treatmen...

Helicobacter pylori (H. pylori) is the causative agent of gastritis, peptic ulcer disease, mucosa associated lymphoid tissue lymphoma and gastric cancer (GC). While this bacterium infects 50% of the world’s population, in Africa its prevalence reach as high as 80% as the infection is acquired during childhood. Risk factors for H. pylori acquisition...

Distribution of Salmonella enterica serovars and their associated virulence determinants is wide-spread among food animals, which are continuously implicated in periodic salmonellosis outbreaks globally. The aim of this study was to determine and evaluate the diversity of five Salmonella serovar virulence genes (invA, pefA, cdtB, spvC and iroN) iso...

This study aimed at characterizing the phenotypic and toxigenic status of circulating strains of cholera during outbreaks in Nigeria, employing molecular typing techniques. Two hundred and one samples of rectal swabs, stool, vomitus, water (from the well, borehole, sachet, stream, and tap) and disinfectants (sodium hypochlorite) were collected from...

Background: Outbreaks of cholera in Africa seem to be unrelenting which has been continuous and recurrent leading to high morbidity and mortality in some quarters. Objective: The objective of this narrative review is to investigate and identify factors responsible for the recurrent outbreaks of cholera in Africa and response strategies that have...

The original version of this article unfortunately contained a mistake. In the introduction, the infectious dose of Vibrio cholerae was written as 103–108 instead of 103-108 cells.

Campylobacter jejuni and Campylobacter coli are among the leading causes of gastroenteritis in humans worldwide, particularly in Africa. Poultry remains a major source of Campylobacter species and a vector of transmission to humans. This pilot study was aimed at isolating and determining the antibiotic susceptibility profiles of Campylobacter spp....

Background: The global prevalence of H. pylori approaches 50%, with prevalence rates between 20 and 40% in developed countries and up to 90% in Africa and other developing nations of the world. Development of H. pylori-associated diseases is determined by a number of virulence factors. This study aimed at determining the prevalence of H. pylori in...

Background: Methicillin resistant Staphylococcus aureus (MRSA) have become a global health problem causing infections in both humans and livestock, ranging from skin and soft tissue to life threatening blood stream infections. The mecA gene is known to confer resistance to MRSA isolates. This study investigated the carriage of mecA gene by MRSA iso...

BACKGROUND: This multicenter study was undertaken to determine the prevalence of Helicobacter pylori (H. pylori) infection among dyspeptic patients with and without type 2 diabetes mellitus (T2DM). METHODS: Patients with dyspepsia were recruited from tertiary teaching hospitals, three in the South-West and one in the South-South regions of Nigeri...

BacKGroUnD: this multicenter study was undertaken to determine the prevalence of Helicobacter pylori (H. pylori) infection among dyspeptic patients with and without type 2 diabetes mellitus (t2DM). MetHoDs: Patients with dyspepsia were recruited from tertiary teaching hospitals, three in the southWest and one in the south-south regions of nigeria,...

Pseudomonas aeruginosa accounts for a significant proportion of nosocomial infections. This study examined the antimicrobial susceptibility pattern and clonal relatedness of P. aeruginosa isolates of clinical and environmental origin. These isolates displayed susceptibility to levofloxacin, ciprofloxacin, gentamicin, imipenem, and ceftazidime of 65...

Objectives: Helicobacter pylori is a pathogenic bacterium that parasitizes the gastric mucous layer and the epithelial lining of the stomach causing duodenal ulcers, gastric ulcers and cardiovascular disease amongst others. This study aimed at establishing the epidemiologic profile of H. pylori infection in gastritis patients presenting at the Mel...

The devastating effect of flooding has led to associated serious health problems and socio-economic implications. Displaced people are faced with being over-crowded in camps with the attendant consequences which include displaced children facing many dangers, especially if they have become separated from their families. Poor nutrition, poor sanitar...

Cronobacter spp. are emerging, opportunistic, food-borne pathogens associated with infections like meningitis, necrotizing enterocolitis and septicaemia in premature and immunocompromised neonates and infants. The phylogenetic relatedness of three Cronobacter species isolated from powdered infant formula retailed in Nigeria was carried out using a...

Background: The aim of the study was to assess clinical and socio-demographic characteristics as well as prior drug usage as risk factors for Helicobacter pylori (H. pylori) infection in Nigeria. Methods: A total of 347 respondents were surveyed by assessing their clinical and socio-demographic characteristics in comparison with the non-invasive go...

Cronobacter spp. are emerging, opportunistic, food-borne pathogens associated with infections like meningitis, necrotizing enterocolitis and septicaemia in premature and immunocompromised neonates and infants. The phylogenetic relatedness of three Cronobacter species isolated from powdered infant formula retailed in Nigeria was carried out using a...

Background: As part of the bid to ensure healthy lives and promote well-being for children, the Sustainable Development Goals were adopted by the United Nations in 2015. Reports show that economically and socially deprived neighbourhoods have an increased risk of under-five mortality. Objectives: To describe the causes of childhood deaths in select...

Objective: To determine the occurrence of 16S rRNA mutations associated with low-level tetracycline resistance in H. pylori isolates from adult dyspeptic patients in South-west, Nigeria. Methods: Antimicrobial susceptibility testing of fifty isolates was determined by E-test for tetracycline. The conserved region (535bp) of the H. pylori tetracy...

Helicobacter pylori (H. pylori) relationship with humans is believed to have originated in Africa and three African H. pylori populations have been identified: hpAfrica1, hpAfrica2 and hpNEAfrica. Actually, H. pylori infection is a ubiquitous infection in developing countries, particularly Africa. In this continent, the prevalence of H. pylori is h...

This study was conducted to compare a conventional method of detecting the parasite in faecal samples and comparing it with molecular methods with reference to multiplex PCR to determine the difference in the level of sensitivity between them and to characterize the parasite detected to aid epidemiological studies. This cross-sectional study was ca...

Background: Gastric ulcer haemorrhage and implication of Helicobacter pylori to stomach and gastric cancer are major health concern in the 21st Century. Objectives: The aim of this study was is to investigate the cyto-protective, healing and anti H. pylori activities of extract and fractions of Nauclea latifolia. Methods: Hydromethanolic stem-bark...

ABSTRACT Objective: To detect Salmonella species and its’ serovars, Salmonella Enteritidis (S. Enteritidis) and Salmonella Typhimurium (S. Typhimurium) in retail raw beef and chicken in Nigerian markets. Methods: A total of 100 samples, including 50 beef and 50 chicken were purchased from retailers in Lagos, Nigeria. Presence of Salmonella species...

Abstract Childhood diarrhea remains one of the most important health issues worldwide with high morbidity and mortality rates majorly in Africa and other developing countries. Several etiological agents have been linked to acute diarrhea in children. Rotavirus has been the major cause of viral childhood diarrhea in Africa however, with the introdu...

This study was aimed at investigating the influence of the print media in the reportage of LF in Nigeria.The nature and extent of media coverage about LF in four major national newspapers namely The Sun, The Guardian, The Nation and The Punch were examined. The period of study ranged from January 2016 to April 2016. Analysis of the newspaper articl...

cagA gene, a marker for the cag pathogenicity island (CagPAI) and a virulent factor in Helicobacter pylori infection codes for 120 to 145 kDa protein that is associated with cytotoxin production and more severe clinical outcomes. The aim of this study was to determine whether any correlation exists between H. pylori CagA protein and the endoscopic...

This study investigated the risk factors associated with cholera epidemic during the 2010 cholera outbreak in some States in Nigeria. Semi-structured questionnaires were administered to consented patients and/or their parents/guardians in Bauchi and Gombe States in North East Nigeria. Few (33.7%) respondents had access to safe and clean drinking wa...