Prevalence of antibodies to measles and rubella in Sana'a, Yemen.

Prevalence of antibodies to measles and rubella was tested in sera collected from 1368 subjects in urban and rural Sana'a. Overall, 11.7% had no antibodies to measles and 14.6% had no antibodies to rubella, despite the fact that measles but not rubella vaccine is included in the vaccination program in Yemen. Of 89 children <5 years of age 49 (55.1%) had no detectable antibodies to measles, demonstrating that supplementary measles immunization campaigns are required to prevent virus circulation. Assessment of measles immune status among infants in the first year of life is required to determine the optimum age for measles vaccination. Rubella vaccination should be considered with care in Yemen.

Increased frequency of the k-ras G12C mutation in MYH polyposis colorectal adenomas.

Colorectal tumours from MYH polyposis patients display an excess of somatic G : C --> T : A transversions in the adenomatous polyposis coli gene. Here, we identify k-ras mutations in nine out of 54 (16.7%) MYH polyposis tumours. Their presence was associated with increased dysplasia and tubulovillous morphology (P=0.005). G : C --> T : A transversions in k-ras were significantly more frequent in MYH polyposis adenomas than in sporadic or familial adenomatous polyposis-associated tumours (P

Oral antibodies to human papillomavirus type 16 in women with cervical neoplasia.

This study investigated the relationship between human papillomavirus type 16 (HPV-16) antibodies detected in oral fluid from women with cervical neoplasia, their HPV-16 antibody seroprevalence, and their cervical HPV-16 DNA presence. Cervical HPV-16 DNA was detected by polymerase chain reaction in 43.2% (35/81) of these women. The prevalence of IgG and IgA antibodies to HPV-16 virus-like particles (VLP-16) in oral fluid and was investigated by enzyme-linked immunosorbent assay. Anti-VLP-16 IgA antibodies were detected in oral fluid from 54.3% (44/81) of women with cervical neoplasia, compared with 8% (3/36) in controls (P = 0.000002). Anti-VLP-16 IgG was detected in oral fluid from 43.2.9% (25/72) and 13.3% (4/30; P = 0.029), respectively. Women who were HPV-16 DNA positive at their cervical lesion, displayed an oral fluid anti-VLP-16 IgA prevalence of 60.7% (17/28) and HPV-16 DNA negative women an oral fluid anti-VLP-16 IgA prevalence of 50% (20/40; P = 0.38). Oral fluid anti-VLP-16 IgG prevalence in HPV-16 DNA positive women was 28.6% (8/28) compared with 40% (16/40) in oral fluid from HPV-16 DNA negative women (P = 0.3). Amongst HPV-16 DNA positive women, the anti-VLP-16 IgG seroprevalence was 75% (21/28) and IgA seroprevalence 35.7% (10/28) and for the HPV-16 DNA negative women these values were 60% (24/40) and 32.5% (13/40), respectively. Oral IgA antibody testing proved no more sensitive than serum antibody detection for the determination of HPV infection but could be useful as a non-invasive screening method for women with cervical neoplasia and for estimating the mucosal antibody response to HPV vaccines.

Cervical lesions are associated with human papillomavirus type 16 intratypic variants that have high transcriptional activity and increased usage of common mammalian codons.

Human papillomavirus type 16 (HPV-16) is a major cause of cervical neoplasia, but only a minority of HPV-16 infections result in cancer. Whether particular HPV-16 variants are associated with cervical disease has not yet been clearly established. An investigation of whether cervical neoplasia is associated with infection with HPV-16 intratypic variants was undertaken by using RFLP analyses in a study of 100 HPV-16 DNA-positive women with or without neoplasia. RFLP variant 2 was positively associated [odds ratio (OR)=2.57] and variant 5 was negatively associated with disease (OR=0.2). Variant 1, which resembles the reference isolate of HPV-16, was found at a similar prevalence among those with and without neoplasia. Variants 1 and 2 were also more likely to be associated with detectable viral mRNA than variant 5 (respectively P=0.03 and P=0.00). When HPV-16 E5 ORFs in 50 clones from 36 clinical samples were sequenced, 19 variant HPV-16 E5 DNA sequences were identified. Twelve of these DNA sequences encoded variant E5 amino acid sequences, 10 of which were novel. Whilst the associations between HPV-16 E5 RFLP variants and neoplasia could not be attributed to differences in amino acid sequences, correlation was observed in codon usage. DNA sequences of RFLP variant 2 (associated with greatest OR for neoplasia) had a significantly greater usage of common mammalian codons compared with RFLP pattern 1 variants.

High prevalence of human papillomavirus type 16 infection among children.

Infection with high-risk human papillomaviruses (HPV), is the most significant risk factor for cervical cancer and it may be possible to prevent this malignancy by immunisation. Before immunisation programmes can be designed, however, it is necessary to know the age of acquisition and all routes of infection for these viruses. Sexual transmission is well documented and vertical transmission has also been demonstrated, although the frequency of transmission remains controversial. We previously showed that vertical transmission frequently results in persistent infection, and now present data on the prevalence of HPV-16 DNA (the most prevalent high-risk HPV type) in healthy children. Buccal samples from 267 healthy children aged 3-11 years were tested for HPV DNA by generic PCR (MY09/MY11), and a HPV-16 specific nested PCR. Reverse transcriptase (RT)-PCR was used to determine the prevalence of transcriptionally active HPV-16 infection in a subset of children. HPV-16 DNA was detected by nested PCR in 138 of 267 (51.7%) samples, whereas HPV DNA was detected in only 45 (16.8%) specimens by generic PCR, that has a lower analytical sensitivity. There were no significant differences in prevalence according to age or sex. Early region mRNA was detected by RT-PCR in six (11.3%) of 53 HPV-16 E5 DNA positive samples. HPV-16 E5 DNA sequences from 10 children confirmed the identity of the sequences detected and identified 13 HPV-16 variants.

Serologic evidence of human herpesvirus 8 transmission by homosexual but not heterosexual sex.

Epidemiologic studies link Kaposi's sarcoma with a sexually transmitted agent. Human herpesvirus 8 (HHV-8) is likely to be that agent, but routes of transmission are poorly described. A seroepidemiologic study was conducted to determine whether HHV-8 is transmitted sexually between heterosexuals. Sera from 2718 patients attending a sexually transmitted disease (STD) clinic were tested for antibodies to HHV-8 and herpes simplex virus type 2 (HSV-2). Information on sex partners in the previous 12 months and past STDs were obtained by questionnaire. Relationships between possible risk factors and HHV-8 infection were assessed by logistic regression. Overall, seroprevalence of HHV-8 was 7.3%. Independent risk factors for HHV-8 in the whole group were homo/bisexuality and birth in Africa and, among homo/bisexual men, a history of syphilis and HSV-2 and human immunodeficiency virus seropositivity. Among heterosexuals there was no evidence for sexual transmission; the only independent risk factor for HHV-8 seropositivity was birth in Africa.

High risk genital papillomavirus infections are spread vertically.

It is well recognised that high-risk human papillomaviruses (HPVs) are spread by sexual activity, but the possibility of non-sexual transmission remains controversial. We present evidence for vertical transmission from at least 30% HPV positive mothers to their infants, resulting in persistent infection in children. That the mother is the source of infant infection has been confirmed by DNA sequencing. We also discuss the evidence for oral HPV-16 infection in children. In our own studies, HPV-16 DNA was detected in buccal cells from 48% children, aged 3-11 and transcriptionally active infection was confirmed in some children. Other studies have reported prevalences of 19%-27% among children less than 11 years of age. Studies that have failed to detect high-risk HPVs in children have used techniques which were insufficiently sensitive to detect the low levels of virus present. Serological studies also suggest that < or = 45% prepubertal children have acquired HPV-16. Thus, convincing evidence is now available for vertical transmission of high risk HPVs, which probably results in widespread infection among children. The consequences of such infections remain to be elucidated.

Human herpesvirus 8: seroepidemiology among women and detection in the genital tract of seropositive women.

An indirect IFA to detect antibodies against latent nuclear antigens of human herpesvirus 8 (HHV-8) was used to determine the prevalence of HHV-8 antibodies in 169 women attending a sexually transmitted diseases clinic and a human immunodeficiency virus (HIV) clinic at a London hospital. Nested polymerase chain reaction was used to detect HHV-8 DNA in 93 blood samples and 89 cervical brush scrapes (CBS). Another 96 CBS from women attending a colposcopy clinic were also analyzed. The overall seroprevalence of HHV-8 was 18.3%. The seroprevalence was higher among women born in Africa (24.7%) than among women born elsewhere (11.5%; P=.06) and was independent of HIV serostatus. HHV-8 DNA was detected in 3 CBS and 6 peripheral blood samples from 11 HHV-8-seropositive women but not in CBS from 78 seronegative women, 96 women from the colposcopy clinic, or in blood samples from 82 seronegative women.

Rubella virus and chronic joint disease: is there an association?

Synovial fluid samples and/or biopsies from 79 patients with various chronic inflammatory joint diseases or traumatic joint injury were tested for rubella virus (RV) in order to confirm or refute results from other studies that suggested RV as a cause of chronic inflammatory joint disease. Sixty-eight of the 72 patients tested had RV antibodies. RV RNA was detected by reverse transcription-PCR in the synovial fluid cells from two patients. RV was also isolated by cell culture from the synovial fluid of one of these two patients. This patient was a 42-year-old female with common variable immune deficiency and Mycoplasma hominis arthritis, while the other was a 68-year-old female with rheumatoid arthritis. While these results fail to confirm that RV is associated with chronic inflammatory joint disease, they suggest that RV may persist within a joint and be reactivated when cell-mediated immunity is suppressed.

Molecular analysis of rubella virus epidemiology across three continents, North America, Europe, and Asia, 1961-1997.

E1 gene nucleotide sequences of 63 rubella virus isolates from North America, Europe, and Asia isolated between 1961 and 1997 were compared phylogenetically. Two genotypes were evident: Genotype I contained 60 viruses from North America, Europe, and Japan, and genotype II contained 3 viruses from China and India. The genotype I isolates prior to 1970 grouped into a single diffuse clade, indicating intercontinental circulation, while most post-1975 viruses segregated into geographic clades from each continent, indicating evolution in response to vaccination programs. The E1 amino acid sequences differed by no more than 3%; thus, no major antigenic variation was apparent. Among 4 viruses from congenital rubella syndrome that occurred following reinfection, only one amino acid substitution occurred in several important epitopes, indicating that antigenic drift is not important in this phenomenon. However, 2 viruses isolated from chronic arthritis exhibited changes in these epitopes. Isolates of the RA 27/3 vaccine strain were readily identifiable by nucleotide sequence.

Proliferative T-cell responses to human papillomavirus type 16 E5 are decreased amongst women with high-grade neoplasia.

Proliferative responses to human papillomavirus type 16 (HPV-16) E5 peptides were determined for short-term cell lines derived from peripheral blood mononuclear cells of 75 women. Cell lines from 16 of the 75 women proliferated in response to stimulation with pooled E5 peptides; this was most common for patients with low-grade squamous cervical intraepithelial lesions (LSIL; 6 of 15 patients, 40%) and less frequent for asymptomatic women with no cervical lesions (4 of 20, 20%), those with high-grade squamous intraepithelial lesions(HSIL; 5 of 33, 15%) and others with cervical cancer (1 of 7, 14%, P = 0.027). Amongst these patients, proliferative responses were exclusive to those that were positive for HPV-16 DNA (12 of 41, 29%; c.f. none of 13 HPV-16 DNA-negative subjects exhibited a proliferative response; P= 0023) and were again most prevalent amongst HPV-16 DNA-positive LSIL (6 of 14, 43%), as compared with HPV-16 DNA-positive HSIL (5 of 23, 22%) or HPV-16 DNA-positive cervical cancer patients (1 of 4, 25%, P > 0.05). In contrast, for asymptomatic women, responsiveness was statistically independent of HPV-16 DNA status, i.e. responsiveness in HPV-16 DNA-positive and DNA-negative subjects was observed in 3 of 15 (20%) and 1 of 5 (20%) cases, respectively (P > 0.05). There were no associations between detection of HPV-16 mRNA and proliferative responses (P> 0.05). These data suggest that HPV-16 E5-specific T-helper activity is depressed amongst women with HSIL lesions.

Transmission of cervical cancer-associated human papilloma viruses from mother to child.

There is now compelling evidence that persistent infection with certain types of human genital papillomaviruses (HPV) may, after many years, lead to cervical cancer. However, HPV have been detected in asymptomatic women, infants and children. Several studies have demonstrated that infants can acquire high-risk HPV infections from their mothers at birth. Thus, the traditional view that cervical-cancer associated HPV infections are primarily sexually transmitted needs to be re-assessed. Accordingly, the role of mother to child transmission of cancer-associated HPVs may need to be investigated further. These facts are pertinent to those developing prophylactic vaccines to prevent high-risk HPV infections and cervical carcinoma.

Relationship between human papillomavirus infection and overexpression of p53 protein in cervical carcinomas and lymph node metastases.

Overexpression of p53 protein is common in cervical carcinoma. We investigated archival biopsies from 26 cervical cancer patients (24 with available lymph nodes) to determine the relationship between p53 overexpression and HPV infection at the cervix and lymph nodes. Twelve cervical carcinoma patients had p53 protein in cervical biopsies detectable by immunohistochemistry using monoclonal antibody DO-1, and 22 were positive for HPV DNA in polymerase chain reaction assays (16, contained HPV-16; 3, HPV-18; and, 3 HPV-X). Seven cervical cancer patients had one or more lymph nodes positive for p53 protein, and all but one of these were concordantly p53 positive at the cervix. However, detection of p53 protein in cervical biopsies was predictive neither of the expression of p53 at draining lymph nodes (P > 0.1) nor of the occurrence of metastases (P > 0.1). Fourteen patients were positive at one or more lymph nodes for HPV DNA. Cervical positivity for HPV DNA was associated significantly with concordant HPV positivity at the lymph nodes (P = 0.039) and was predictive of metastases (P = 0.019). There was no association between positivity for p53 and for HPV DNA at primary cervical carcinomas or at the lymph nodes (all P > 0.1). We conclude that, although detectable p53 protein is a common feature of cervical carcinomas, it is not predictive of metastases and is independent of HPV infection.

Polymerase chain reaction protocols for the detection of DNA from mucosal human papillomavirus types -6, -11, -16, -18, -31 and -33.

Individual types of human papillomaviruses (HPV) which infect mucosal surfaces have been implicated as the causative agents for carcinomas of the cervix, anus, penis, larynx and the buccal cavity, occasional periungal carcinomas, as well as benign anogenital warts. The identification of particular HPV types is thus important for: identifying patients with premalignant lesions who are at risk of progression to malignancy; epidemiological studies; studies of the natural history of these viruses; and even medico-legal cases of suspected sexual abuse of children. In this protocol we describe PCR assays for: the identification of DNA from the mucosal HPVs types -6, -11, -16, -18, -31 and -33; a consensus HPV PCR for detecting DNA from 20 characterised mucosal HPVs, as well as more than 25 novel HPVs; and, for a control PCR for beta-globin.

Detection of human papillomavirus type 16 early-gene transcription by reverse transcription-PCR is associated with abnormal cervical cytology.

Human papillomavirus type 16 (HPV-16) is associated with abnormal Papanicolou smears, indicative of cervical intraepithelial neoplasia. HPV-16 is the most common genital HPV and is found in up to 40% of young women with normal cervical cytology. In order to investigate whether transcriptionally active HPV-16 infection is associated with abnormal cervical smears, a reverse transcription-nested PCR assay with primers from the E5 open reading frame was developed to detect all HPV-16 early-region mRNA (E-mRNA) transcripts. It was used to study HPV-16-infected women with normal and abnormal cervical cytologies to obtain evidence of active infection. Among HPV-16 DNA-positive women, HPV-16 E-mRNA was detected in 15 of 37 (40.5%) women with abnormal cervical cytology but in only 4 of 35 (11.4%) women with normal cytology (P = 0.007). Thus, HPV-16 E-mRNA transcription is associated with abnormal cervical smears and may have value as a prognostic marker of progressive disease.

Nucleotide sequence analysis of a major antigenic domain of the E1 glycoprotein of 22 rubella virus isolates.

We have determined the nucleotide sequence of the region of the rubella virus genome which encodes amino acids 195-296 of the E1 glycoprotein (E1-195-296) from a panel of 22 rubella viruses obtained from Europe, USA and Asia between 1963-1995. E1-195-296 contains neutralizing and haemagglutinating determinants, and may represent a major antigenic domain. The nucleotide sequence divergence of the 22 rubella viruses compared to the Therien strain sequence ranged from 0.65-7.14%. The greatest sequence divergence occurred in two rubella viruses of Indian origin, and was more than twofold greater than that previously reported for rubella virus. The majority of nucleotide changes occurring in the 22 viruses did not effect the deduced amino acid sequence of E1-195-296. Two rubella viruses isolated from cases of reinfection in pregnancy did not exhibit nucleotide sequence variation resulting in changes in the deduced amino acid sequence of E1-195-296, suggesting that antigenic change within this region of E1 is not associated with rubella reinfection. A rubella virus isolated from a synovial fluid sample exhibited a nucleotide substitution in a putative neutralization domain contained within E1-195-296. Phylogenetic analysis was performed to study the relationship between E1-195-296 coding sequences of the 22 viruses in this report and corresponding sequences of other rubella viruses in the databank.