Pathogenic microbial flora of genital ulcers in Sheffield with particular reference to herpes simplex virus and Haemophilus ducreyi

Spatial distribution and determinants of iron supplementation among pregnant women in Ethiopia: a spatial and multilevel analysis

BACKGROUND

Maternal anemia continues as a global public health concern particularly in developing countries including Ethiopia. It is associated with an increased risk of maternal death, obstetric complications, preterm birth, and low birth weight. Even though maternal anemia is the commonest problem in Ethiopia, there is limited evidence on the spatial distribution and determinants of iron supplementation. Therefore, this study aimed to investigate the spatial distribution and determinants of iron supplementation among pregnant women in Ethiopia.

METHOD

A secondary data analysis was conducted based on the 2016 Ethiopian Demographic and Health Survey (EDHS) data. A total weighted sample of 7589 women was included for analysis. For the spatial analysis; ArcGIS version 10.6, and SaT Scan version 9.6 statistical software were employed to explore the spatial distribution, and to identify significant hotspot areas of iron supplementation in Ethiopia. For the determinant factors, multilevel logistic regression analysis was fitted to identify significant individual and community level determinants of iron supplementation. Deviance, Median Odds Ratio (MOR), and Intra-class Correlation Coefficient (ICC) were used for model comparison and for assessing model fitness. Variables with a p-value of less than 0.2 in the bivariable analysis were considered in the multivariable multilevel analysis. In the multivariable multilevel analysis, the Adjusted Odds Ratio (AOR) with 95% Confidence Interval (CI) was used to declare significant determinants of iron supplementation.

RESULTS

The spatial distribution of iron supplementation was significantly varied across the country with Global Moran's index value of 0.3 (p < 0.001). The SaTScan analysis identified a total of 271 significant clusters, of these 89 clusters were primary clusters located in the Southwest Somali and Central Oromia regions (LLR = 66.69, P < 0.001, RR = 1.35). ANC visit (AOR = 3.66, 95%CI: 3.21, 417), community education [AOR = 1.31, 95%CI, 1.07, 1.59), media exposure (AOR = 1.33, 95%CI: 1.15, 1.53), distance to health facility (AOR = 1.32, 95%CI: 1.16, 1.50), region and household wealth index were statistically significant determinant factors of iron supplementation.

CONCLUSION

Iron supplementation among pregnant women were significantly varied across the country. Therefore, the finding of this study could help to design effective public health interventions targeting areas with low iron supplementation and maternal health services should be delivered in all areas of our country. Besides, public health programs should enhance iron supplementation through promoting ANC visits, media exposure, and giving special emphasis to marginalized and remote areas.

Biology of Haemophilus ducreyi

The etiological agent of the sexually transmitted genital ulcer disease chancroid was first described in 1889 by Auguste Ducrey following repeated autoinoculation of purulent ulcer material from a series of patients. The organism was isolated on artificial media a decade later but has remained difficult to isolate consistently, resulting in controversy over its characteristics and role as the causative agent of chancroid. Because of its fastidious growth requirements, including unknown components in blood, the organism was included in the original description of the genus Haemophilus. Requirement for exogenous hemin and limited phenotypic characteristics, including structural and antigenic properties, suggested that Haemophilus ducreyi was a valid member of the genus Haemophilus. Recent studies of respiratory quinones, deoxyribonucleic acid hybridization, and competition for homologous transformation of the type species, H. influenzae, suggest that H. ducreyi is unrelated to any of the present species of the family Pasteurellaceae, which includes members of the genera Haemophilus, Actinobacillus, and Pasteurella. This review summarizes the early studies with H. ducreyi and our current knowledge of the microbiology of this important human pathogen.

Chancroid and Haemophilus ducreyi

Haemophilus ducreyi is the causative agent of chancroid, one of the genital ulcerative diseases. H. ducreyi is the major cause of genital ulcer disease in Africa and Southeast Asia and is of increasing concern in the United States. Definitive diagnosis of chancroid requires the isolation and identification of H. ducreyi, but isolation of this organism is difficult and the available medium is not optimal for all strains. Fluorescent antibody and serologic tests are of limited value. In general, our knowledge of this organism is rather limited, and indeed, recent studies have questioned the placement of H. ducreyi in the genus Haemophilus. H. ducreyi has relatively few biochemical activities, and epidemiologic studies are limited because there are limited phenotypic markers available for strain typing. Specific virulence factors of H. ducreyi have yet to be identified. Antimicrobial resistance in H. ducreyi is of special concern, as this organism has acquired both gram-negative and gram-positive resistance determinants. In addition, some of these determinants can be mobilized and transferred to other Haemophilus species or to Neisseria gonorrhoeae.

Aetiology of genital ulceration in the Gambia

The aetiology of genital ulceration was studied in 104 unselected patients (94 men, 10 women) attending a sexually transmitted disease (STD) clinic in the Gambia. Chancroid was diagnosed in 54 (52%), syphilis in 23 (22%), lymphogranuloma venereum (LGV) in seven (7%), and herpes in six (6%). In 28 (27%) patients no diagnosis was reached. Ten (10%) patients were found to have both chancroid and syphilis, three (3%) had both LGV and syphilis, and one (1%) had both herpes and syphilis. Trimethoprim 160 mg and sulphamethoxazole 800 mg twice daily for one week was found to be effective in the treatment of chancroid. This regimen with a single intramuscular injection of benzathine penicillin 2.4 MIU is recommended for the treatment of genital ulcers in Gambian health centres without laboratory facilities.

Clinical and microbiological evaluation of 46 episodes of genital ulceration

In 44 consecutive patients 46 episodes of genital ulceration were studied. The presumptive clinical diagnosis was evaluated by extensive microbiological investigations. In 15 (33%) episodes the clinical diagnosis did not accord with the microbiological one. Chancroidal lesions were most commonly found to have other microbiological aetiology. Secondary invasion of treponemal or viral lesions by other bacterial species (mostly anaerobes or pyogenic cocci) or genital pyodermia were the cause of confusion in six of nine cases of chancroid. In the other three a ducreyilike bacterium was found. Direct Gram staining of ulcer material did not help the diagnosis of chancroid. The implications of the results of this study for clinical practice are discussed.

Immunoblot analysis of antigens associated with Haemophilus ducreyi using serum from immunised rabbits

Sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting were used to characterise isolates of Haemophilus ducreyi. Isolates of H ducreyi were heterogeneous in protein composition, but isolates from single outbreaks appeared similar both in protein profiles and antigenic analysis. Rabbits immunised with H ducreyi responded with a vigorous humoral immune response in which multiple antigenic polypeptides were detected. The most prominent antigens had molecular masses of 67, 42, 22.5, and 20 kilodaltons.

Susceptibility of Haemophilus ducreyi to ampicillin and sulbactam in vitro

The MICs of ampicillin, ampicillin plus sulbactam in equal proportions, and a range of ampicillin concentrations with a constant 0.5 micrograms/ml concentration of sulbactam were determined for 66 strains of Haemophilus ducreyi by an agar dilution technique with standardized inocula prepared by ultrasonication. Fifty-five strains were susceptible to ampicillin alone (MIC range, 0.06 to 1 microgram/ml). The MICs for the 11 resistant strains were (micrograms per milliliter): range, 8 to greater than 16; MIC for 50% of the strains tested (MIC50), greater than 16; MIC90, greater than 16; 8 of them produced beta-lactamase. In the presence of an equal concentration of sulbactam, the MICs for ampicillin-resistant strains were lowered to (micrograms per milliliter): range, 0.125 to 2; MIC50, 0.25; MIC90, 1. In the presence of a fixed 0.5-micrograms/ml concentration of sulbactam, the MICs for the resistant strains were (micrograms per milliliter): range, 0.125 to 2; MIC50, 0.125; MIC90, 0.25. Sulbactam-ampicillin appears to be suitable for the treatment of H. ducreyi infections, especially those caused by ampicillin-resistant strains.

Efficacy of oral treatment with acyclovir and co-trimoxazole in first episode genital herpes

Forty patients presenting with first episode genital herpes were randomly allocated to seven day treatment with oral acyclovir alone, placebo alone, oral acyclovir plus co-trimoxazole, or placebo plus co-trimoxazole. Patients receiving acyclovir had significantly shorter periods of viral shedding (p less than 0.001), pain (p = 0.03), and times to lesion healing (p less than 0.05). Averaged over all patients there was no evidence that co-trimoxazole affected any of the variables, though in women cotrimoxazole was associated with a shorter time to lesion healing (p less than 0.01). Furthermore, the combination treatment gave significantly shorter times to lesion healing than acyclovir alone, placebo alone, or placebo and co-trimoxazole (p = 0.01) and good trends elsewhere (external lesions and duration of pain). Neither drug was associated with any adverse events or toxicity or influenced the subsequent recurrence rate.

Anaerobic bacteria and herpes simplex virus in genital ulceration

Of 91 patients with genital ulceration, herpes simplex virus was isolated from 52 (57%) and Haemophilus ducreyi from 12 (13%); none had syphilis. The difference in incidence of other aerobes in patients and controls was not significant. Anaerobes, predominantly Bacteroides spp, were isolated from a large proportion (77%) of men and women patients with ulcers but from few control men. The most common anaerobic species were B asaccharolyticus and B ureolyticus, with fewer isolates of the melaninogenicus/oralis group. The bacterial flora of herpetic and non-herpetic ulcers were similar, but Candida albicans was isolated significantly more often from non-herpetic ulcers. Anaerobic bacteria may contribute to the pathogenesis of genital ulcers.

Oropharyngeal Haemophilus ducreyi infection

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