Assessment of the contamination potentials of some foodborne bacteria in biofilms for food products

AbstractObjectiveTo assess biofilms formed by different bacterial strains on glass slides, and changes in biofilm mass and biofilm-associated cell populations after brief contacts between biofilms and either media agar or food products.MethodsTwo Listeria monocytogenes and Escherichia coli (E. coli) strains and a single Staphylococcus aureus (S. aureus) strain were inoculated separately in tryptic soy broth containing glass coupons incubated for 24, 48 or 72 h at 37 °C. The biofilms formed by individual bacterial strains and biofilm-associated cell populations were determined. Biofilms were subsequently allowed to have brief contacts (1-3 times), through gentle touching, with either agar, meat or soft white cheese (2 cm3). Changes in biofilm mass on glass slides and cell populations embedded in biofilms were quantified.ResultsA nonpathogenic E. coli formed more biofilms than an E. coli O157:H7 strain. Biofilms formed by S. aureus and Listeria monocytogenes were essentially similar. The biofilm mass increased as incubation time increased within 48 h of incubation and was not positively correlated with cellulose production. Biofilm mass at 48 and 72 h of incubation was not significantly different. More frequent contacts with agar or foods did not remove more biofilms or biofilm-associated cells from glass slides. More S. aureus biofilms were removed followed by Listeria and E. coli biofilms. Mean contamination of agar or food models was 0.00 to 7.65 log CFU/cm2. Greater contaminations in cell populations were observed with S. aureus and Listeria biofilms.ConclusionsThe results provide a clearer assessment of contaminating potential of foods that comes in contact with them

Dengue fever in Nigeria: a mini review

Dengue is a disease caused by dengue virus. It is a major mosquito-borne viral disease of humans that is endemic in areas of tropical and subtropical regions, which are environmentally suitable for vector propagation. The disease poses a major threat to the overwhelmed and weak public healthcare delivery system in the developing world, especially in Africa where febrile illnesses are common. The disease undermines the fight against febrile illnesses as infection with dengue often remains undetected or misdiagnosed as malaria or other febrile diseases. This review article highlights dengue epidemiology in Nigeria, dengue transmission dynamics, pathogenesis, diagnosis and current interventions strategies, challenges in addressing dengue infection and future prospects towards dengue elimination. The literature search for publications on dengue virus infection in Nigeria was performed using Google Scholar, PubMed, Web of Science, African Journals Online and other scholarly online databases. Dengue remains a threat to Nigeria and other African countries. In Nigeria, the occurrence of this infection remains a low priority in the public health sector even though it has been reported in about 17 states across the country. The reports of dengue infection in all the geo-political zones suggests active transmission of dengue, hence the need to consider other etiologies of febrile illnesses and engage the public to sustain local involvement as local risk to dengue outbreaks is linked to the population’s knowledge, attitude and behavioral practices that encourage vector breedin

Serovarovi i biokemijske osobine izolata bakterije Escherichia coli izdvojenih kod kolibaciloze i iz zadušaka kokoši u Zariji, Nigerija

This study was designed to determine the isolation rate, serovars and biochemical profiles of E. Coli from cases of colibacillosis and dead-in-shell embryos in Zaria-Northern Nigeria. The isolation rate of E. coli from hatcheries studied were 4.67% and 7.50% from farms of Simtu Agricultural Company and National Animal Production Research Institute (NAPRI) Shika Zaria, Nigeria respectively. Twenty E. coli isolates from clinical cases of colibacillosis were also used for this study. The Simtu farm E. coli isolates showed 97.5% motility, while isolates from both NAPRI and clinical colibacillosis cases were 100% motile. The results of carbohydrate fermentation are variable without specific character, except for E. coli isolates from clinical cases of colibaccillosis that showed 100% fermentation especially for lactose, ducitol, rhamnose and xylose. The major serovars recorded from clinical cases of colibacillosis were serovars O8:K50 and O9:K30. Serovars from the dead-in-shell embryos were O78:K80, O8:K50, O9:K30, and O26:K60. Untypable isolates made up the greatest percentage of serogroup of E. coli studied. The antibiotic susceptibility testing indicated that many of the isolates were resistant to more than one antibiotic. Ciprofloxacin was the antibiotic to which majority of isolates were sensitive (85% of the clinical cases and 100% of both the Simtu and the NAPRI farms’ isolates). It is concluded that other methods for controlling E. coli should be evaluated, so that the emergence of resistant isolates be limited and the cost involved in prophylactic and therapeutic treatment programs be reducedIstraživanje je provedeno radi određivanja stope izdvajanja, serotipizacije i određivanja biokemijskih osobina izolata E. coli kod kolibaciloze peradi i zadušaka u Zariji u sjevernoj Nigeriji. Stopa izdvajanja E. Coli iz promatranih valionica bila je 4,67% na 7,50% farmi Poljoprivrednoga dobra Simtu i Nacionalnog instituta za proizvodnju i istraživanje životinja, Shika Zaria, Nigerija. Dvadeset izolata E. coli izdvojenih iz peradi oboljele od kolibaciloze bilo je također upotrijebljeno u istraživanju. 97,5% izolata E. coli s farme Simtu bilo je pokretljivo, dok su izolati Nacionalnog instituta i oni izdvojeni kod kliničke kolibaciloze bili 100% pokretljivi. Rezultati fermentacije ugljikohidrata bili su varijabilni, osim u izolata kod kliničke kolibaciloze u kojih je dokazana fermentacija laktoze, dulcitola, ramnoze i ksiloze. Glavni serovarovi ustanovljeni kod kliničke kolibaciloze bili su O8:K50 i O9:K30. Iz zadušaka su bili izdvojeni serovarovi O78:K80, O8:K50, O9:K30 i O26:K60. Izolati se najvećim dijelom nisu mogli tipizirati unutar pretraživanih seroloških skupina. Mnogi izolati bili su otporni na više antibiotika. Većina sojeva (85% izdvojenih kod kliničke kolibaciloze te 100% s farme Simtu i Nacionalnoga instituta) bila je osjetljiva prema ciprofloksacinu. Zaključuje se da treba vrednovati druge metode za kontrolu E. coli tako da bi se pojava otpornih sojeva mogla ograničiti te smanjiti troškovi profilakse i terapij

Serovarovi i biokemijske osobine izolata bakterije Escherichia coli izdvojenih kod kolibaciloze i iz zadušaka kokoši u Zariji, Nigerija

This study was designed to determine the isolation rate, serovars and biochemical profiles of E. Coli from cases of colibacillosis and dead-in-shell embryos in Zaria-Northern Nigeria. The isolation rate of E. coli from hatcheries studied were 4.67% and 7.50% from farms of Simtu Agricultural Company and National Animal Production Research Institute (NAPRI) Shika Zaria, Nigeria respectively. Twenty E. coli isolates from clinical cases of colibacillosis were also used for this study. The Simtu farm E. coli isolates showed 97.5% motility, while isolates from both NAPRI and clinical colibacillosis cases were 100% motile. The results of carbohydrate fermentation are variable without specific character, except for E. coli isolates from clinical cases of colibaccillosis that showed 100% fermentation especially for lactose, ducitol, rhamnose and xylose. The major serovars recorded from clinical cases of colibacillosis were serovars O8:K50 and O9:K30. Serovars from the dead-in-shell embryos were O78:K80, O8:K50, O9:K30, and O26:K60. Untypable isolates made up the greatest percentage of serogroup of E. coli studied. The antibiotic susceptibility testing indicated that many of the isolates were resistant to more than one antibiotic. Ciprofloxacin was the antibiotic to which majority of isolates were sensitive (85% of the clinical cases and 100% of both the Simtu and the NAPRI farms’ isolates). It is concluded that other methods for controlling E. coli should be evaluated, so that the emergence of resistant isolates be limited and the cost involved in prophylactic and therapeutic treatment programs be reducedIstraživanje je provedeno radi određivanja stope izdvajanja, serotipizacije i određivanja biokemijskih osobina izolata E. coli kod kolibaciloze peradi i zadušaka u Zariji u sjevernoj Nigeriji. Stopa izdvajanja E. Coli iz promatranih valionica bila je 4,67% na 7,50% farmi Poljoprivrednoga dobra Simtu i Nacionalnog instituta za proizvodnju i istraživanje životinja, Shika Zaria, Nigerija. Dvadeset izolata E. coli izdvojenih iz peradi oboljele od kolibaciloze bilo je također upotrijebljeno u istraživanju. 97,5% izolata E. coli s farme Simtu bilo je pokretljivo, dok su izolati Nacionalnog instituta i oni izdvojeni kod kliničke kolibaciloze bili 100% pokretljivi. Rezultati fermentacije ugljikohidrata bili su varijabilni, osim u izolata kod kliničke kolibaciloze u kojih je dokazana fermentacija laktoze, dulcitola, ramnoze i ksiloze. Glavni serovarovi ustanovljeni kod kliničke kolibaciloze bili su O8:K50 i O9:K30. Iz zadušaka su bili izdvojeni serovarovi O78:K80, O8:K50, O9:K30 i O26:K60. Izolati se najvećim dijelom nisu mogli tipizirati unutar pretraživanih seroloških skupina. Mnogi izolati bili su otporni na više antibiotika. Većina sojeva (85% izdvojenih kod kliničke kolibaciloze te 100% s farme Simtu i Nacionalnoga instituta) bila je osjetljiva prema ciprofloksacinu. Zaključuje se da treba vrednovati druge metode za kontrolu E. coli tako da bi se pojava otpornih sojeva mogla ograničiti te smanjiti troškovi profilakse i terapij

Antimicrobial resistance as a global public health threat: the way forward

Increased antimicrobial resistance (AMR) of bacterial and fungal pathogens pose a significant threat to public health, as it reduces the effectiveness of antibiotic and other antimicrobial drugs, making the control of infections difficult or almost impossible. This condition arises when microorganisms evolve and develop adaptive mechanisms to withstand the effects of the drugs which are designed to kill them. The emergence and spread of these antimicrobial pathogens that have acquired new resistance mechanisms continue to endanger and undermine efforts to treat common infections. As a result, an increase in morbidity and mortality due to bacterial and fungal infections has been observed with a ripple effect of economic hardship. The primary drivers of AMR include misuse and abuse in human, animal and the environment. To address this threat, it is important to have a good understanding of the cause, consequences, as well as the potential control strategies. Due to the cause and nature of AMR, a multidisciplinary approach is necessary in combating the threat posed by this condition. Some of the strategies through which AMR can be combatted include public health awareness, proper antibiotic use, accurate diagnosis, and research into the development of newer antimicrobial agents and alternative treatments. Additionally, the use of improved surveillance and monitoring systems are important in tracking patterns of resistance and provide guide towards the development of effective intervention strategies. Hence, this review focused on bacterial and fungal resistance to increase awareness and the way forward on this growing threat to human existenc

High Genetic Similarity of MRSA ST88 Isolated From Pigs and Humans in Kogi State, Nigeria

We determined the prevalence and genetic characteristics of methicillin-resistant Staphylococcus aureus (MRSA) isolated from pigs and humans between September 2013 and February 2015 in Kogi State, a central region in Nigeria. A total of 680 nasal swabs were collected and analyzed from pigs (n = 425) and “pig-contact” humans (n = 55) on 35 farms, and “non-pig-contact” humans (n = 200). MRSA was recovered from 20 (4.7%) pigs on 12 farms and 18 (7.0%) humans. Six (2.4%) of the human isolates were recovered from “pig-contact” humans, of which only three work on farms also harboring MRSA positive pigs. All 38 MRSA were resistant to β-lactams only, belonged to spa type t1603, sequence type (ST) 88, and mecA was associated with a SCCmec IVa element. Four isolates from a pig, a pig-contact human from the same farm, a pig-contact human from a pig farm in a different district, and a non-pig-contact human were subjected to whole genome sequencing (WGS). Core genome SNP analysis revealed high genetic similarity between strains (3–11 SNP differences), despite the temporal (2 year gap) and geographic (165 km) differences between isolates. Furthermore, these Nigerian isolates form a distinct clade when compared to other African MRSA ST88 isolates. All but one porcine strain was positive for scn suggesting a possible human origin and that pigs were either transiently contaminated by humans or result of a very recent human-to-pig transmission event. To our knowledge, this is the first report of genetically confirmed MRSA in pigs in Nigeria, which appear to be a typical CA-MRSA clone present in the human population

Serological and Molecular Survey for Dengue Virus Infection in Suspected Febrile Patients in Selected Local Government Areas in Adamawa State, Nigeria

Dengue is a disease caused by the dengue virus that is primarily transmitted by Aedes aegypti mosquitoes. Currently, the disease poses a threat to public health, with about 390 million people reported to be infected annually across the endemic regions of the world. In Nigeria, the disease is under-reported and often misdiagnosed as malaria. This study was designed to conduct a serological and molecular survey for dengue virus infection in febrile patients in three Local Government Areas (LGAs) in Adamawa State, Nigeria, from September through December 2020. Serum samples from 424 patients were analysed by Enzyme-Linked Immunosorbent Assay (CALBIOTECH, Dengue Virus IgM ELISA). Thick and thin smear microscopic techniques were used to determine the presence of malaria parasites. Overall, 19.4% patients were sero-positive for dengue in the three study locations. A total of 11%, 14.5% and 12.3% participants were found to be co-infected with dengue and malaria in Mubi, Jimeta and Numan, respectively. The CDC DENV1-4 RT-PCR Assay reagent was used for serotype-specific detection and identification of circulating serotypes. From the ELISA-positive samples, 11 (2.6%) cases were confirmed to be dengue serotype 1 by Real-Time PCR and sequencing and were found to be in circulation in all the three study areas. With an overall sero-prevalence of 19.4%, dengue virus infection may be one of the major causes of febrile illnesses across the study locations; hence, public healthcare professionals should not neglect other aetiologies of febrile illnesses and the need to conduct laboratory diagnoses to determine the possible causes of febrile illnesses

Additional file 3: of Helminths of veterinary and zoonotic importance in Nigerian ruminants: a 46-year meta-analysis (1970–2016) of their prevalence and distribution

List of studies excluded from the meta-analysis. (DOCX 19 kb

Additional file 2: of Helminths of veterinary and zoonotic importance in Nigerian ruminants: a 46-year meta-analysis (1970–2016) of their prevalence and distribution

Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) checklist. (DOC 62 kb