The first report on epidemiology of oropharyngeal Kingella kingae carriage in Scandinavian children: K. kingae carriage is very common in children attending day care facilities in Western Norway.

Kingella kingae colonizes the upper airways in children and has been recognized as the most common causative agent of osteoarticular infections (OAI) in children below 4 years of age. This is the first Scandinavian study to investigate oropharyngeal K. kingae carriage in healthy children. From June 2015 to August 2016, we recruited 198 healthy children aged 11-14 months from routine consultations at health promotion centers in Hordaland County, Norway for a cross-sectional study. After their parents had provided informed consent; demographic data were registered, and an oropharyngeal swab was collected. The oropharyngeal swab was analyzed with a real-time PCR assay specific to K. kingae targeting the RTX toxin locus. Results showed an asymptomatic carriage rate of 12.6%. A striking and highly significant difference was observed between the children that had started attending day care facilities as compared with children still being at home (33.33% vs 8.5%; p < 0.001). K. kingae is prevalent in young children in Norway. This study emphasize that K. kingae should be considered an important etiological agent in OAI. Transmission seems to be facilitated in day care facilities. The correlation between oropharyngeal carriage and OAI needs to be further explored.

A new human challenge model for testing heat-stable toxin-based vaccine candidates for enterotoxigenic Escherichia coli diarrhea - dose optimization, clinical outcomes, and CD4+ T cell responses.

TRIAL REGISTRATION: ClinicalTrials.gov ClinicalTrials.gov, Project ID: NCT02870751.

Experimental Infection of Human Volunteers with the Heat-Stable Enterotoxin-Producing Enterotoxigenic Escherichia coli Strain TW11681.

Infection with enterotoxigenic Escherichia coli (ETEC) producing the heat-stable enterotoxin (ST) is one of the most important causes of childhood diarrhoea in low- and middle-income countries. Here, we undertook a controlled human infection model (CHIM) study to investigate whether ST-producing ETEC strain TW11681 would be suitable for testing the protective efficacy of new ST-based vaccine candidates in vaccine challenge models. In groups of three, nine volunteers ingested 1 × 106, 1 × 107, or 1 × 108 colony-forming units (CFU) of TW11681. Flow cytometry-based assays were used to measure CD4+ T cell responses and antibody levels targeting virulence factors expressed by the strain. We found that infection with TW11681 elicited few and mild symptoms, including mild diarrhoea in two volunteers, both of whom ingested 1 × 106 CFU. Averaged across all volunteers, the CD4+ T cell responses specific for E. coli YghJ mucinase peaked 10 days after infection (3.2-fold (p = 0.016)), while the CD4+ T cell responses specific for Colonization Factor Antigen I (CFA/I) major fimbrial subunit (CfaB) peaked after 28 days (3.6-fold (p = 0.063)). The serum CfaB-specific anti-IgA and anti-IgG/IgM levels were significantly increased and peaked 3 months after infection. Both remained elevated for the duration of the 12-month follow-up. The corresponding anti-YghJ serological response was strongest after 10 days, although a significant increase was seen only for IgA levels (3.2-fold (p = 0.008)). In conclusion, due to its low diarrhoea attack risk, TW11681 is probably not suitable for testing the efficacy of new vaccines in human challenge studies at doses 1 × 106 to 1 × 108. However, the strain may still be useful in CHIMs for studying ETEC host-pathogen interactions.

Reproductive health problems in rural South African young women: risk behaviour and risk factors.

BACKGROUND: South African young women continue to be vulnerable, with high prevalence of teenage pregnancy, HIV, sexually transmitted infections (STIs) and female genital schistosomiasis (FGS). This study seeks to examine the underlying factors that may be associated with these four adverse reproductive health outcomes. METHODS: In a cross-sectional study of 1413 sexually active of young women, we explored these four adverse reproductive health outcomes by considering socio-demographic factors, socio-economic factors, sexual risk behaviour, substance abuse and knowledge about reproductive health by using a questionnaire. Consenting participants were asked about previous pregnancies and were tested for HIV, STIs and FGS. Multivariable regression analyses were used to explore the factors associated with these four reproductive health outcomes. RESULTS: 1. Early pregnancy: Among the young women, 44.4% had already been pregnant at least once. Associated factors were hormonal contraceptives, (adjusted odds ratio (AOR): 17.94, 95% confidence interval (CI): 12.73-25.29), and sexual debut < 16 years (AOR: 3.83, 95% CI: 2.68-5.47). Living with both parents (AOR 0.37, 95% CI: 0.25-0.57) and having a steady partner (AOR: 0.43, 95% CI: 0.24-0.76) were identified as protective factors against pregnancy. 2. HIV: HIV prevalence was 17.1%. The odds of having HIV were higher in intergenerational (AOR: 2.06, 95% CI: 1.05-4.06) and intragenerational relationships (AOR: 1.51 95% CI: 1.06-2.15), compared to age-homogenous relationships. Other associated factors were: condom use (AOR: 1.60, 95% CI: 1.16-2.20), number of times treated for an STI (AOR: 1.32, 95% CI: 1.02-1.71), and total number of partners (AOR: 1.14, 95% CI: 1.03-1.28). 3. STIs: Participants who had at least one STI (40.5%) were associated with total partner number (AOR 1.17, 95% CI: 1.06-1.30), and testing HIV positive (AOR: 1.88, 95% CI 1.41-2.50). 4. FGS: FGS prevalence (19.7%) was associated with previous anti-schistosomal treatment (AOR: 2.18, 95% CI: 1.57-3.05). CONCLUSION: There is a high prevalence of pregnancy, HIV, STIs and FGS among sexually active young women in rural KwaZulu-Natal. Multidisciplinary approaches are urgently needed for educational and health literacy programs prior to sexual debut, and health care facilities, which should be made accessible for young women.

High-risk human papillomavirus types in HIV-infected and HIV-uninfected young women in KwaZulu-Natal, South Africa: implications for vaccination.

BACKGROUND: High-risk human papillomavirus (hr-HPV) infections and low-grade squamous intraepithelial lesions occur frequently in young women. The available vaccines cover up to seven hr-HPV genotypes (HPV16, HPV18, HPV31, HPV33, HPV45, HPV52 and HPV58) and two low-risk HPV types (HPV6 and HPV11). The objective of this study was to describe the hr-HPV genotypes present among HIV-uninfected and HIV-infected young women in rural high schools. METHODS: Cervicovaginal lavages were obtained from sexually active young women recruited from high schools in KwaZulu-Natal (n = 1223). HPV testing was done by the polymerase chain reaction using GP5+/GP6 + primers and enzyme immunoassay. HIV testing was done using rapid test kits. RESULTS: Of the 1223 cervicovaginal lavages, 301 (25%) were positive for hr-HPV. The HPV prevalence was higher in HIV infected (32.20%, 95% CI: 0.27-0.38) than in HIV-uninfected women (22.50%, 95% CI: 0.21-0.26), (p = .001). Similarly, multiple infections were slightly more common in HIV infected (59.32%) than in HIV-uninfected women (53.51%), (p = .37). The nine predominant genotypes in descending order were HPV types 16 (n = 99, 22.10%), 51 (n = 58, 12.91%), 18 (n = 56, 12.50%), 35 (n = 50, 11.10%), 33 (n = 47, 10.82%), 56 (n = 42, 9.31%), 45 (n = 34, 7.60%), 52 (n = 32, 7.14%) and 59 (n = 31, 6.91%). HPV 35, 51, 56 and 59 (40.62%), which are not covered by any vaccine, were among the most prevalent in the schools of KwaZulu-Natal. CONCLUSION: Four of the most predominant high-risk HPV types in this region are not covered by the new nine-valent HPV vaccine.

The first step toward diagnosing female genital schistosomiasis by computer image analysis.

Schistosoma haematobium causes female genital schistosomiasis (FGS), which is a poverty-related disease in sub-Saharan Africa. Furthermore, it is co-endemic with human immunodeficiency virus (HIV), and biopsies from genital lesions may expose the individual to increased risk of HIV infection. However, microscopy of urine and hematuria are nonspecific and insensitive predictors of FGS and gynecological investigation requires extensive training. Safe and affordable diagnostic methods are needed. We explore a novel method of diagnosing FGS using computer color analysis of colposcopic images. In a cross-sectional study on young women in an endemic area, we found strong associations between the output from the computer color analysis and both clinical diagnosis (odds ratio [OR] = 5.97, P < 0.001) and urine microscopy for schistosomiasis (OR = 3.52, P = 0.004). Finally, using latent class statistics, we estimate that the computer color analysis yields a sensitivity of 80.5% and a specificity of 66.2% for the diagnosis of FGS.

Schistosoma haematobium infection and CD4+ T-cell levels: a cross-sectional study of young South African women.

Schistosoma (S.) haematobium causes urogenital schistosomiasis and has been hypothesized to adversely impact HIV transmission and progression. On the other hand it has been hypothesized that HIV could influence the manifestations of schistosomiasis. In this cross-sectional study, we explored the association between urogenital S. haematobium infection and CD4 cell counts in 792 female high-school students from randomly selected schools in rural KwaZulu-Natal, South Africa. We also investigated the association between low CD4 cell counts in HIV positive women and the number of excreted schistosome eggs in urine. Sixteen percent were HIV positive and 31% had signs of urogenital schistosomiasis (as determined by genital sandy patches and / or abnormal blood vessels on ectocervix / vagina by colposcopy or presence of eggs in urine). After stratifying for HIV status, participants with and without urogenital schistosomiasis had similar CD4 cell counts. Furthermore, there was no significant difference in prevalence of urogenital schistosomiasis in HIV positive women with low and high CD4 cell counts. There was no significant difference in the number of eggs excreted in urine when comparing HIV positive and HIV negative women. Our findings indicate that urogenital schistosomiasis do not influence the number of circulating CD4 cells.

Colourimetric image analysis as a diagnostic tool in female genital schistosomiasis.

Female genital schistosomiasis (FGS) is a highly prevalent waterborne disease in some of the poorest areas of sub-Saharan Africa. Reliable and affordable diagnostics are unavailable. We explored colourimetric image analysis to identify the characteristic, yellow lesions caused by FGS. We found that the method may yield a sensitivity of 83% and a specificity of 73% in colposcopic images. The accuracy was also explored in images of simulated inferior quality, to assess the possibility of implementing such a method in simple, electronic devices. This represents the first step towards developing a safe and affordable aid in clinical diagnosis, allowing for a point-of-care approach.

Cervical ectopy: associations with sexually transmitted infections and HIV. A cross-sectional study of high school students in rural South Africa.

OBJECTIVES: It has been hypothesised that ectopy may be associated with increased susceptibility to sexually transmitted infections (STIs). In this cross-sectional study, we wanted to explore the association between STIs (including HIV) and cervical ectopy. METHODS: We included 700 sexually active young women attending randomly selected high schools in a rural district in KwaZulu-Natal, South Africa. The district is endemic of HIV and has a high prevalence of STIs. We did computer-assisted measurements of the ectocervical area covered by columnar epithelium (ectopy) in colposcopic images and STI analyses on cervicovaginal lavage and serum samples. All participating women answered a questionnaire about sexual behaviour and use of contraceptives. RESULTS: The mean age was 19.1 years. Ectopy was found in 27.2%, HIV in 27.8%, chlamydia in 25.3% and gonorrhoea in 15.6%. We found that age, parity, chlamydia and gonorrhoea, years since menarche, years since sexual debut and number of sexual partners were associated with ectopy. In multivariate analysis with chlamydia infection as the dependent variable, women with ectopy had increased odds of having chlamydia infection (adjusted OR 1.78, p=0.033). In women under 19 years of age, we found twofold higher odds of being HIV-positive for those with ectopy (OR 2.19, p=0.014). CONCLUSIONS: In conclusion, cervical ectopy is associated with Chlamydia trachomatis infection and HIV in the youngest women.

Effect of female genital schistosomiasis and anti-schistosomal treatment on monocytes, CD4+ T-cells and CCR5 expression in the female genital tract.

BACKGROUND: Schistosoma haematobium is a waterborne parasite that may cause female genital schistosomiasis (FGS), characterized by genital mucosal lesions. There is clinical and epidemiological evidence for a relationship between FGS and HIV. We investigated the impact of FGS on HIV target cell density and expression of the HIV co-receptor CCR5 in blood and cervical cytobrush samples. Furthermore we evaluated the effect of anti-schistosomal treatment on these cell populations. DESIGN: The study followed a case-control design with post treatment follow-up, nested in an on-going field study on FGS. METHODS: Blood and cervical cytobrush samples were collected from FGS negative and positive women for flow cytometry analyses. Urine samples were investigated for schistosome ova by microscopy and polymerase chain reaction (PCR). RESULTS: FGS was associated with a higher frequency of CD14+ cells (monocytes) in blood (11.5% in FGS+ vs. 2.2% in FGS-, p = 0.042). Frequencies of CD4+ cells expressing CCR5 were higher in blood samples from FGS+ than from FGS- women (4.7% vs. 1.5%, p = 0.018). The CD14+ cell population decreased significantly in both compartments after anti-schistosomal treatment (p = 0.043). Although the frequency of CD4+ cells did not change after treatment, frequencies of CCR5 expression by CD4+ cells decreased significantly in both compartments (from 3.4% to 0.5% in blood, p = 0.036; and from 42.4% to 5.6% in genital samples, p = 0.025). CONCLUSIONS: The results support the hypothesis that FGS may increase the risk of HIV acquisition, not only through damage of the mucosal epithelial barrier, but also by affecting HIV target cell populations, and that anti-schistosomal treatment can modify this.