Persistence of HPV infection and risk of high-grade cervical intraepithelial neoplasia in a cohort of Colombian women

Little is known about the dynamics of human papillomavirus (HPV) infection and subsequent development of high-grade cervical intraepithelial neoplasia (CIN2/3), particularly in women >30 years of age. This information is needed to assess the impact of HPV vaccines and consider new screening strategies. A cohort of 1728 women 15–85 years old with normal cytology at baseline was followed every 6 months for an average of 9 years. Women with squamous intraepithelial lesions were referred for biopsy and treatment. The Kaplan–Meier method was used to estimate the median duration of infection and Cox regression analysis was undertaken to assess determinants of clearance and risk of CIN2/3 associated with HPV persistence. No difference in the likelihood of clearance was observed by HPV type or woman's age, with the exception of lower clearance for HPV16 infection in women under 30 years of age. Viral load was inversely associated with clearance. In conclusion, viral load is the main determinant of persistence, and persistence of HPV16 infections carry a higher risk of CIN2/3.

Incidence and isolation of bluetongue virus infection in cattle of the Santo Tomé Department, Corrientes Province, Argentina

Sentinel herds were monitored for the detection of bluetongue (BT)-specific antibodies and virus over two periods, namely: June 1999 to August 2000 and September 2000 to April 2001. Herds were located in Santo Tomé (Herds 1 and 2) where BTV activity was known to occur. From June 1999 to August 2000, the cumulative incidence (CI) of bluetongue virus (BTV) infection was 0% and 35% in Herds 1 and 2, respectively. In the second period, the CI of BTV infection was 10% and 97% in Herds 1 and 2, respectively. The virus was isolated from red blood cells of animals that seroconverted and was identified as serotype 4. Averages of the monthly maximal temperatures were always above 19 degrees C. However, averages of the monthly median temperatures were below 19 degrees C and averages of the monthly minimal temperatures were below 15 degrees C from May 2000 to August 2000. There was no viral activity detected at that time. Culicoides insignis was identified as the predominant potential vector species (99%) trapped near sentinel herds. Although clinical disease has never been reported in Argentina, viral activity was detected and the virus has been isolated in sentinel herds.

Prevalence and determinants of Chlamydia trachomatis infections in women from Bogota, Colombia

OBJECTIVES

Chlamydia trachomatis infection in the cervix and uterus has been hypothesised to be a co-factor for cervical cancer. We performed a cross sectional study in Bogota, Colombia, where cervical cancer rates are high, to determine the prevalence and determinants of C trachomatis infection, and in particular its association with human papillomavirus (HPV).

METHODS

1829 low income sexually active women were interviewed and tested for C trachomatis, using an endogenous plasmid PCR-EIA, and for 37 HPV types, using a general primer GP5+/6+ mediated PCR-EIA.

RESULTS

The overall prevalence of C trachomatis was 5.0%, and it did not differ substantially between women with normal (5.0%) and those with abnormal (5.2%) cervical cytology. Women infected with any HPV type (15.1%) had a slightly increased risk of being simultaneously infected with C trachomatis (adjusted OR 1.3, 95% CI: 0.8 to 2.4). This association was stronger when multiple HPV infections (adjusted OR 2.5, 95% CI: 1.1 to 5.9) were present. No other lifestyle or reproductive characteristics were clearly associated with risk of C trachomatis infection.

CONCLUSIONS

HPV infected women, particularly women with multiple HPV infections, are at increased risk of being infected with C trachomatis.

Low grade squamous intra-epithelial lesions and human papillomavirus infection in Colombian women

Low grade squamous intra-epithelial lesions could be considered as a manifestation of human papillomavirus exposition, however the discrepancy between rates of infection with human papillomavirus and development of low grade squamous intra-epithelial lesions is notable. Here we report a cross-sectional three-armed case-control study in the Colombian population, to compare the risk factors of women with low grade squamous intra-epithelial lesions with that of human papillomavirus DNA-negative and positive women with normal cytology.

Prevalence and determinants of HPV infection among Colombian women with normal cytology

Human papillomavirus is the principal risk factor associated with cervical cancer, the most common malignancy among women in Colombia. We conducted a survey, aiming to report type specific prevalence and determinants of human papillomavirus infection in women with normal cytology. A total of 1859 women from Bogota, Colombia were interviewed and tested for human papillomavirus using a general primer GP5+/GP6+ mediated PCR-EIA. The overall HPV DNA prevalence was 14.8%; 9% of the women were infected by high risk types, 3.1% by low risk types, 2.3% by both high risk/low risk types and 0.4% by uncharacterized types (human papillomavirus X). Thirty-two different human papillomavirus types were detected, being human papillomavirus 16, 58, 56, 81(CP8304) and 18 the most common types. The human papillomavirus prevalence was 26.1% among women younger than 20 years, 2.3% in women aged 45-54 years, and 13.2% in women aged 55 years or more. For low risk types the highest peak of prevalence was observed in women aged 55 years or more. Compared to women aged 35-44 years, women aged less than 20 years had a 10-fold increased risk of having multiple infections. Besides age, there was a positive association between the risk of human papillomavirus infection and number of regular sexual partners and oral contraceptive use. In women aged below 25 years, high educational level and having had casual sexual partners predicted infection risk. In conclusion, there was a broad diversity of human papillomavirus infections with high risk types being the most common types detected. In this population multiplicity of sexual partners and, among young women, high educational level and casual sexual partners seem to determine risk.

[Bluetongue: isolation and characterization of the virus and identification of vectors in northeastern Argentina]

To establish if BTV was circulating in Argentina, 94 bovines from the Santo Tomé and Ituzaingó Departments of Corrientes Province were sampled every 30-60 days during 14 months. Red blood cells from those animals that showed seroconvertion with a c-ELISA were processed for virus isolation by inoculation in embryonated chicken eggs and cell cultures. Cells with CPE were positive by direct and indirect immunofluorescence with BTV specific reagents. These samples examined by electron microscopy showed virus particles with BTV morphological characteristics. Blood samples and tissue culture supernantants were positive by RT-PCR technique with primers corresponding to the segment 3 of the BTV genome. Haematophagous insects were captured in one farm using light traps and Culicoides insignis Lutz was the predominant species detected. This is the first isolation of BTV in Argentina from northeastern bovines without any disease symptom.

Periodontal disease among indigenous people in the Amazon rain forest

BACKGROUND

People are not all equally susceptible to periodontitis. To understand the epidemiology and natural history of this disease, it is important to study populations with varying genetic backgrounds and environmental exposures.

AIM

Characterize the periodontal condition of a sample of indigenous adults in a remote region of the Amazon rain forest and determine the association of periodontal disease with various demographic, behavioral and environmental factors.

METHODS

A cross-sectional evaluation of 244 subjects aged 20-70 years was conducted. Pocket depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), plaque and calculus were assessed for the Ramfjord index teeth.

RESULTS

These people had high levels of plaque, calculus and BOP. The mean PD was rather shallow (2.45 mm in 20-29 year-olds to 2.73 mm in 50+ year-olds) and did not increase significantly with age. Mean CAL (0.57 mm in 20-29 year-olds and 2.26 mm in 50+ year-olds) and mean location of the free gingival margin in relation to the cemento-enamel junction changed significantly with age (p<0.0001). Multivariate analysis revealed that increasing age, bleeding on probing and calculus scores were positively associated with mean CAL (p<0.01). Sex, ethnicity, level of modern acculturation, use of coca or tobacco paste, frequency of dental visits and plaque were not associated with mean CAL.

CONCLUSIONS

Periodontal disease in these people was mainly associated with gingival recession rather than deep pockets. Most people had clinical attachment loss but despite poor oral hygiene and extensive gingival inflammation, they did not have very severe periodontal destruction.

Associations of periodontal disease with femoral bone mineral density and estrogen replacement therapy: cross-sectional evaluation of US adults from NHANES III

The objectives of this study were to evaluate the possible association of periodontal disease with (1) femoral bone mineral density (BMD), and (2) estrogen replacement therapy in a large sample of US adults (N= 11,655). The mean clinical attachment loss (CAL) per person was the main outcome variable. Based on the total BMD of the proximal femur and using the WHO diagnostic criteria, subjects were classified as having osteoporosis, osteopenia, or normal BMD. After adjusting for confounders, females with high calculus scores and low BMD had significantly more CAL than females with normal BMD and similar calculus scores (p<0.0001). No association was observed among women with low and intermediate levels of calculus. The greater CAL present among women with low BMD was associated with gingival recession. Patterns of findings were similar but equivocal among men, of whom only 66 were osteoporotic. After adjustment for possible confounders, postmenopausal women who reported having used estrogen replacement therapy presented significantly less mean CAL than those who never used estrogen. These findings indicate that in the presence of high calculus scores, females with osteoporosis are at increased risk for attachment loss and that this risk may be attenuated by the use of estrogen replacement therapy.

Human herpesviruses and Porphyromonas gingivalis are associated with juvenile periodontitis

BACKGROUND

Although herpesviruses have been associated with adult periodontitis, their relationship with juvenile periodontitis (JP) has not been established. This case-control study examined possible associations between JP and pathogenic bacteria, the human cytomegalovirus (HCMV), and the Epstein-Barr type 1 virus (EBV-1).

METHODS

Subjects were participants in a larger survey of schoolchildren in North-Central Jamaica. Subgingival plaque samples from 15 subjects with JP, 20 with incipient periodontitis (IP), and 65 randomly-selected healthy controls were assayed for Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans using a 16S rRNA polymerase chain reaction (PCR) identification method, and for HCMV and EBV-1 using nested PCR identification.

RESULTS

Strong bivariate associations were found between JP and P. gingivalis (odds ratio [OR] = 12.7; 95% CI = 2.6, 61.4), HCMV (OR = 10.0; 95% CI = 2.7, 36.3), and A. actinomycetemcomitans (OR = 8.0; 95% CI = 2.3, 27.5), but not EBV-1. In multivariate analyses, P. gingivalis remained a significant explanatory variable (OR = 7.8; 95% CI = 1.5, 40.9); however, the associations were marginal for HCMV (OR = 4.6; 95% CI = 0.9, 22.7), and non-significant for A. actinomycetemcomitans (OR = 2.0; 95% CI = 0.4, 9.7). The associations with JP and the extent of attachment loss were even stronger when both P. gingivalis and HCMV were detected together. P. gingivalis (OR = 3.9; 95% CI = 1.3, 12.0) and EBV-1 (OR = 3.3; 95% CI = 1.0, 10.3) were the only significant explanatory variables in the multivariate analysis of IP.

CONCLUSIONS

P. gingivalis is the strongest and most stable indicator of periodontitis in Jamaican adolescents. Co-infection with P. gingivalis and HCMV appears to be particularly deleterious to periodontal health.