A review of the current diphtheria outbreaks

Corynebacterium diphtheriae is responsible for both endemic and epidemic diphtheria. The predisposing factor for this disease is the failure to immunize during childhood. Humans are the only hosts of the organism and is present in the upper respiratory tract. The organism is transmitted via airborne route and can cause respiratory obstruction and heart failure because of the exotoxin it produces. There is presently a resurgence of diphtheria outbreaks in Nigeria. The Nigeria Center for Disease Control (NCDC) was notified of suspected diphtheria outbreaks in Lagos and Kano States, Nigeria, in December 2022 and has been issuing monthly reports since that time. This review of the diphtheria outbreaks following online database searches on PubMed and Google Scholar as well as the NCDC/WHO websites and grey literatures, describes the current trend of the outbreaks globally, elucidated the different strains of Corynebacterium responsible for the outbreaks, identified the recent vaccine formulation developed to tackle the outbreaks, and provide information on vaccine delivery and efficacy studies in the country and globally.

Diagnostic utility of QuantiFERON-TB gold in-tube in active pulmonary Tuberculosis in Nigeria.

BACKGROUND: The high positive responses obtained in active TB indicate that IGRAs may be useful in diagnosing active TB. This study aimed at evaluating the usefulness of Quantifer on-TB Gold-in Tube test (QFT-IT) in the diagnosis of active TB among Nigerians. METHODS: This study prospectively enrolled sputum smear positive TB cases and healthy disease free controls. Basic demographic and clinical data were collected using a structured questionnaire. Venous blood was collected into the QTF-IT tubes, incubated for 16-24 hours, serum harvested and stored at -200C till analysed in a batch. Tuberculin skin test (TST) was also done using 5TU and read within 48-72 hours. The performances of QFT-IT and TST among the cases and controls were compared. RESULTS: Sixty one TB cases and 41 controls were enrolled. The mean (SD) age of the TB cases was higher than the controls, 35.14+4.3 yrs v 27.8 + 2.1, p<0.001. Forty three (70.5%), 13 (21.3%) and 5 (8.2%) of the cases had a positive, negative and indeterminate QFT-IT results respectively compared with 14 (34.1%), 25 (61%), and 2 (4.9%) of the controls respectively, p values <0.001, 0.005 and 0.05 respectively. Fifty eight(95%) and 29(70.7%) of the TB cases and controls had a positive TST result respectively while 3 (5%) and 12( 29.3%) of the TB cases and controls had a negative TST result respectively, p values 0.003 each .QFT-IT had a sensitivity of 76% (95% CI 61.8 -85.2%) while the sensitivity of TST was 96.6% (95% CI 88.5 -98.3%), p = 0.07. The specificity of QFT-IT was 63.7% (95% CI 46-76%) and 30% (95% CI 20- 56%) for TST, p =0.001. Positive Likelihood ratio was 1.7 (95% CI 1.06-2.85) for QFT-IT and 1.4 (95%CI 1.06-1.8) for TST, p =0.002. Among the cases, both TST and QFT-IT were positive in 43(70.5%) and both negative in 1 (1.6%), and overall test .agreement was 77.7% (Kappa =0.13; p= 0.07). Female sex and higher total lymphocytes count were significantly associated with a positive QFT results. CONCLUSION: IGRA has a higher specificity and positive likelihood ratio in TB cases. Our findings indicate that QFT-IT may be a good adjunct tool to diagnose TB disease.

Invasive Bacteria Isolates from Children with Severe Infections in a Nigerian Hospital

Background: Little information is available about the aetiology and epidemiology of serious bacterial infections in Nigeria. This study determined bacterial isolates from blood and cerebrospinal fluid (CSF) of children presenting in the emergency room of a teaching hospital in Nigeria. Method: From October 2005 to December 2006; children aged two to 60 months presenting with signs of acute systemic infections were recruited. Blood culture and CSF specimens were collected and processed using standard microbiological protocols. Data were analysed using SPSS version 11 software. Results: Two hundred and two blood and 69 CSF samples were cultured. Fifty-five (27) of the blood cultures yielded Gram-negative bacilli and Gram-positive cocci in almost equal proportions. The most common isolates from the blood cultures were Staphylococcus aureus; 26 (12.9) and atypical coliforms; 13 (6.5). Others are Klebsiella spp; 3 (1.5); Klebsiella pneumonia; 2 (1.0); Escherichia coli; 3 (1.5); Enterobacter agglomerans; 2 (1.1); Proteus mirabilis; 2(1); Pseudomonas spp; 2 (1.0); Haemophilus influenza; 1 (1.0); and Coagulase-negative Staphylococcus; 1 (1.0). Fourteen out of 67 (20.9) of the CSF samples yielded bacterial isolates: Streptococcus pneumonia; 3 (4.5); Haemophilus influenza; 8 (11.9); Hemophilus spp; 1 (1.5); E. Coli; 1 (1.5); and atypical coliform; 1 (1.5). Gram-negative coliform isolates were predominantly resistant to penicillin based antibiotics and co-trimoxazole but sensitive to third-generation cephalosporins and quinolones. A high percentage of S. aureus isolates were multi-drug resistant. Conclusions: Bacterial infections contribute to the significant morbidity among children in our environment. S. aureus was more frequently isolated in sepsis while H. influenzae appears to play a major role in meningitis. Appropriate use of antibiotics is needed to manage affected children effectively. We also recommend improved vaccine coverage of children under the age of five years) of the blood cultures yielded Gram-negative bacilli and Gram-positive cocci in almost equal proportions. The most common isolates from the blood cultures were Staphylococcus aureus; 26 (12.9) and atypical coliforms; 13 (6.5). Others are Klebsiella spp; 3 (1.5); Klebsiella pneumonia; 2 (1.0); Escherichia coli; 3 (1.5); Enterobacter agglomerans; 2 (1.1); Proteus mirabilis; 2(1); Pseudomonas spp; 2 (1.0); Haemophilus influenza; 1 (1.0); and Coagulase-negative Staphylococcus; 1 (1.0). Fourteen out of 67 (20.9) of the CSF samples yielded bacterial isolates: Streptococcus pneumonia; 3 (4.5); Haemophilus influenza; 8 (11.9); Hemophilus spp; 1 (1.5); E. Coli; 1 (1.5); and atypical coliform; 1 (1.5). Gram-negative coliform isolates were predominantly resistant to penicillin based antibiotics and co-trimoxazole but sensitive to third-generation cephalosporins and quinolones. A high percentage of S. aureus isolates were multi-drug resistant.Conclusions: Bacterial infections contribute to the significant morbidity among children in our environment. S. aureus was more frequently isolated in sepsis while H. influenzae appears to play a major role in meningitis. Appropriate use of antibiotics is needed to manage affected children effectively. We also recommend improved vaccine coverage of children under the age of five years

The bacteriology of open fractures in Ile-Ife, Nigeria.

BACKGROUND: The objective of this study is to determine the pattern of bacterial isolates and antibiotic sensitivity profile in open fractures. Fifty-nine patients with open fractures of the lower limb long bones were studied. The majority of the cases were Gustilo and Anderson types II 21(35.6%), and IIIA 16(27.1%). METHOD: The patients were assessed by history taking, physical examination, and plain radiographs. Wound swabs were taken for bacteriological studies. Other necessary investigations were also done. During wound debridement open fractures were classified into Grades I, II and III using the Gustilo-Anderson method of classification. RESULTS: The infection rate was 45.8%. Gram-positive cocci and Gram-negative rods were isolated. On the whole Staphylococcus aureus 13(25%), and Coagulase-negative staphylococci (CONS) 14(26.9%), were the commonest organisms isolated. The commonest Gram-negative rods that were isolated from the wounds were Proteus mirabilis 9(17.3%), and Pseudomonas aeruginosa 8(15.4%). Multiple organisms were commonly isolated from the wounds. While all the organisms isolated showed very good sensitivity to gentamicin, cloxacillin and ofloxacin, most of the organisms were resistant to penicillin, ampicillin and tetracycline. The sensitivity ranged from 62.5% to 100%. Coagulase-negative Staphylococci (CONS) showed sensitivity to the widest range of antibiotics which included penicillin, ampicillin, chloramphenicol, gentamicin, cloxacillin and ofloxacin. The sensitivity ranged from 35.7% to 100%. There was statistically significant difference between the open tibial and femoral fracture cases with respect to the interval between injury and debridement time (p = 0.008); the rate of wound infection (p = 0.021); and the occurrence of osteomyelitis (p = 0.023). The commonest complications observed were wound infection 27(45.8%), and delayed fracture union 26(44.1%), which were commoner in the open tibial fractures. CONCLUSION: This study shows that Staphylococcus aureus and coagulase-negative staphylococci (CONS) were the commonest organisms associated with open fracture of the lower limbs in our centre and that delay in the initial wound debridement was a major predisposing factor to wound infection.

Effect of socio-economic status, age and sex on antibody titre profile to Salmonella typhi/paratyphi in Ile-Ife, Nigeria.

BACKGROUND: Typhoid fever remains a great socio-medical problem in many poor and underdeveloped countries, with an estimated 16 million cases and 600,000 deaths occurring each year. Although it has a world wide distribution, typhoid fever is endemic where sanitary controls are inadequate. The distribution of the infection in relation to age and sex has shown that typhoid fever is more prevalent in males than in females with out satisfactory explanation. Also, those in their second and third decades are more susceptible. The aim of the study is to evaluate the effect of socio-economic status, age and sex on antibody titre profile to Salmonella typhi and praratyphi in Ile-Ife, using both healthy individuals with immunological scar to Salmonella typhi/paratyphi and enteric fever patients. METHOD: Healthy volunteers (310) were recruited into the study and clinically diagnosed/culture proven cases (48) were used as control. Widal text was performed on each serum. Slide agglutination was first done, then positive samples were further subjected to tube agglutination for quantitative titration. RESULTS: The relationship between age and antibody titres in both healthy subjects and enteric fever patients is not statistically significant, (P values > 0.05). From the study also, sex and social status do not influence antibody titres to salmonella typhi/paratyphi (P value > 0.05). CONCLUSION: The study has shown that age, sex and social class do not statistically influence antibody titre profile to S. typhi/paratyphi in Ile-Ife, south western Nigeria.

The characterization of bacterial isolates from acute otitis media in Ile-Ife, southwestern Nigeria.

The incidence of acute otitis media (AOM) in a comprehensive healthcare setting was investigated in Ile-Ife, Nigeria. Out of the 617 children examined, 53 (11.64 per cent) suffered from the condition based on the criteria used. Staphylococci constituted the predominant organisms associated with the condition with Staphylococcus aureus (25.0 per cent) being the most frequent single microbe recovered from the subjects. This was followed by Proteus mirabilis (16.2 per cent), Staphylococcus sp. (8.8 per cent), Streptococcus pneumoniae (8.8 per cent), Pseudomonas aeruginosa and Haemophilus influenzae (7.4 per cent each). Most isolates tested were multiply resistant to the antibiotics commonly employed in treating infections caused by these organisms. The study highlights the prevalence of multi-resistant organisms amongst the subjects and recommends prompt therapeutic intervention to avert ineffectiveness of antibiotics when used in treating infections caused by these organisms in the community.

Role of Campylobacter jejuni/coli in diarrhoea in Ile-Ife, Nigeria.

BACKGROUND: Campylobacter jejuni/coli are well established causative agents of diarrhoea. In Nigeria, gastroenteritis due to C. jejuni was first reported in northern part of the country in 1981 and the South-Western part in Ile-Ife in 1983. OBJECTIVE: To re-examine the role of C. jejuni as an agent of diarrhoea after more than a decade at Ile-Ife, Nigeria and to determine the biological characteristics of local strains. DESIGN: A prospective case control study. SETTING: Obafemi Awolowo University Teaching Hospitals Complex (OAUTHC) Ile-Ife, Nigeria. SUBJECTS: Three hundred and three children with diarrhoea and 100 children with other medical conditions other than diarrhoea were randomly selected. MAIN OUTCOME MEASURES: Isolation of C. jejuni/coli from stool samples collected from the patients and controls. Biological characteristics of the isolates. RESULTS: Fifty eight (19.1%) and 6% of the patients and controls, had the organism respectively. Campylobacter coli accounts for 53.3% of isolates. All the isolates were susceptible to erythromycin and there was no evidence of beta-lactamase production. CONCLUSION: Campylobacter jejuni is an important diarrhoea agent in our environment and should be considered strongly in children with diarrhoea. Complete characterization of local, strains is necessary.

A study of orofacial bacterial infections in elderly Nigerians.

This retrospective study was designed to determine the pattern of occurrence, and principles of management of orofacial bacterial infections in elderly Nigerians. Ninety-two patients aged 55-90 years (mean +/- SD 62.4 +/- 7.5 years), were admitted into the study (male:female ratio 1.1:1). The origin of orofacial infection was predominantly odontogenic and the lower face was three times more commonly involved. The percentage of patients with underlying systemic disease was 16.2%. Patients with underlying disease had a 3.5 times greater risk of developing orofacial infections. Similarly, a significant correlation was demonstrated between both sexes of patients with orofacial infections and underlying illness (P < 0.05). There was a general delay before presenting for treatment (average 19.5 weeks) and the mortality rate was 3.3%. The study findings demonstrate that a significant relationship exists between elderly Nigerians with orofacial infections and systemic disease.

Sero-prevalence of HIV antibodies in tuberculosis patients in Ile-Ife, Nigeria.

BACKGROUND: The acquired immunodeficiency syndrome (AIDS) is of major public health concern worldwide more so in sub-Saharan Africa where there is an upsurge in the incidence of the disease. Reports from developed countries have shown that a close link exists between the human immunodeficiency virus (HIV) and pulmonary tuberculosis. No such study has ever been carried out in Ile-Ife, Nigeria. OBJECTIVE: The study was designed to determine the prevalence of HIV infection among randomly selected tuberculosis patients seen in a Nigerian chest clinic using third generation ELISA kits that detect HIV-1 and HIV-2 strains. RESULTS: Of the 79 subjects with confirmed active tuberculosis, 12.7% tested positive for HIV antibodies compared with 2.0% of subjects without tuberculosis designated as the control group--a value that is statistically significant (p < 0.05). Farmers, artisans and students contributed a large proportion of the seropositive sera. Although the seroprevalence rate of 12.7% is low compared with the rates from eastern and southern African countries, this value was threefold higher than 5.2% value reported in metropolitan Lagos--suggesting concern about the spread of HIV in a semi-urban centre such as Ile-Ife. CONCLUSION: This study suggests that a close link exists between active tuberculosis and HIV infection in Ile-Ife, Nigeria which underscores the urgent need to monitor tuberculosis patients as the increase in the rate of new cases may indicate the spread of HIV infection. The study also recommends that an aggressive public awareness programme be undertaken to enlighten communities about the risk of TB/HIV infection.

The bacteriology of neonatal septicaemia in Ile-Ife, Nigeria.

The incidence of septicaemia among neonates categorized as being at high risk was 55 per cent in Ile-Ife, Nigeria. Gram-positive organisms, specifically Staphylococcus aureus, were predominant (33.8 per cent) among bacteria cultured from proven cases of septicaemia. Other coagulase-negative staphylococci also contributed 21 per cent, with Staphylococcus epidermidis occurring in 5 per cent of the isolates. Listeria monocytogenes was cultured from 8.4 per cent of septic neonates. Pseudomonas aeruginosa was cultured from 3 per cent, Klebsiella pneumoniae from 14 per cent, and Escherichia coli from 7 per cent. Other Gram-negative bacilli cultured were Enterobacter aerogenes (5 per cent), Citrobacter freundii, Salmonella sp., and Proteus sp. (2 per cent each). The bacterial isolates were relatively resistant to antibiotics traditionally employed to treat cases of septicaemia. The study shows a high prevalence of neonatal bacterial sepsis at the centre and the emerging role of Listeria monocytogenes in the aetiology of neonatal sepsis. It highlights the preponderance of multiple antibiotic resistant organisms among these neonates early in life which is of epidemiological importance in the control of the infectious agents.

Incidence of pathogenic microorganisms in clinical specimens from hospitals in south-western Nigeria.

The pattern and frequency of bacterial isolates cultured from 687 clinical specimens from four University teaching hospitals in South Western Nigeria were determined. A total of 707 bacterial isolates were cultured from 18 different clinical sources giving an average of 1.03 bacteria per sample identified in this collection. Of these, gram negative rods constituted 78.1% and the rest were staphylococci. The most common organism isolated in urine samples was E. coli (32.1%) whilst S. aureus (28.9%) was the most frequently isolated organism from wounds. An interesting observation was the significant occurrence of Aeromonas hydrophilia and Klebsiella pneumoniae in urine samples.