Infection with high‐risk HPV types among female sex workers in northern Vietnam

Vaccines against two high‐risk human papillomavirus (HPV) types, HPV‐16, and HPV‐18, are in use currently, with high efficacy for preventing infections with these HPV types and consequent cervical cancers. However, circulating HPV types can vary with geography and ethnicity. The aim of this study was to investigate the prevalence of HPV types and the association between HPV types and abnormal cervical cytology among female sex workers in Northern Vietnam. Cervical swabs and plasma samples were collected from 281 female sex workers at two health centers in Hanoi and Hai Phong in 2009. The HPV L1 gene was amplified by PCR using original and modified GP5⁺/6⁺ primers. Amplified PCR products were genotyped by the microarray system GeneSquare (KURABO) and/or clonal sequencing. Of the 281 women, 139 (49.5%) were positive for HPV DNA. Among the HPV‐positive samples, 339 strains and 29 different types were identified. Multiple‐type and high risk‐type HPV infections were found in 85 (61.2%) and 124 (89.2%) women, respectively. The most common genotype was HPV‐52, followed by HPV‐16, HPV‐18, and HPV‐58. Abnormal cervical cytology was detected in 3.2% (9/281) of the women, and all of these samples were positive for HPV‐DNA. Age ≤25 years and infection with human immunodeficiency virus were associated positively with HPV infection among the women while ever smoking was associated negatively. These results show that HPV‐52 is most prevalent among female sex workers in Northern Vietnam, most of whom had normal cervical cytology. This information may be important for designing vaccination strategies in Vietnam. J. Med. Virol. 85:288–294, 2013. © 2012 Wiley Periodicals, Inc.     

Prevalence and viral load of oncogenic human papillomavirus types associated with cervical carcinoma in a population of North Italy

A cross‐sectional study was carried out in a population of North Italy to determine the prevalence of eight oncogenic human papillomavirus (HPV) types most commonly found in cervical carcinoma and to study the relationship between HPV DNA loads and severity of disease. A total of 597 cervical samples obtained from patients with pathological findings (n = 472) and from women with normal cytology (n = 125) were analyzed by means of normalized Real‐time PCR assays to quantify HPV‐16, ‐18, ‐31, ‐45, and ‐33 group (including ‐33, ‐52, ‐58, ‐67); the normalization of oncogenic HPV viral load was carried out by quantitation of a single copy gene. The two most common oncogenic HPV types found were 16 and 31 (24.3% and 22.9% of pathological samples, respectively); multiple infections were demonstrated in 22% of pathological samples. Overall, the HPV total viral load was found to increase with increasing severity of associated lesions, although a stronger association was observed only for HPV‐31 and HPV‐16 (γ = 0.49 and 0.41, respectively) as compared to HPV‐18 and ‐33 group (γ = 0.19 and 0.02, respectively). However, we found that high levels of HPV‐31 or 33 group DNA could be prognostic of minor oncogenic risk for high‐grade squamous intraepithelial lesions (H‐SIL) (age adjusted odds ratio [AORs] = 1.57 and 1.26, respectively) than HPV‐16 and HPV‐18 (AORs = 30 and 8, respectively). The AORs also increased with HPV total viral load and reached a maximum of AORs = 15.7. Thus, HPV load is a type‐dependent risk marker for the development of H‐SIL. J. Med. Virol. 81:278–287, 2009. © 2008 Wiley‐Liss, Inc.     

Prevalence and type distribution of high‐risk human papillomavirus infection in women undergoing voluntary cervical cancer screening in Italy

The aim of this survey was to assess the prevalence and distribution of oncogenic human papillomavirus (HPV) genotypes in women who underwent screening for cervical cancer in Italy. The correlation of genotypes with the cytological results was also evaluated. Cervical samples were collected from 9,947 self‐referring women for cervical cancer screening. Participants were screened by liquid‐based cytology and high‐risk HPV testing using the Hybrid Capture 2 test. Positive samples were genotyped by PCR. Samples (1,474; 14.8%) were positive for high‐risk HPV. The prevalence was 29.4% in the 15–19 years‐group, decreasing progressively to 6.1% at 50–54 years of age and increasing to 12.2% in those aged over 65 years. HPV 16 was the genotype detected most frequently followed by HPV 31, HPV 18, HPV 56, and HPV 51. HPV 16 or 18 were present in 4% of women with normal cytology and both were detected contemporarily in only 14 women. Twenty‐two percent of atypical squamous cells, 26% of low‐grade and 56% of high‐grade squamous intraepithelial lesions at cytology were positive for HPV 16 and/or 18. The prevalence of HPV infection in Italy is in agreement with that reported worldwide. HPV 16 was the prevalent genotype. The concomitant infection with HPV 16 and HPV 18 (vaccine targets) was found rarely. Apart from HPV 16 and 18, there was a substantial presence of HPV genotypes against which the vaccines available currently have shown cross‐protection efficacy. The findings of this study may contribute to reliable predictions on the potential efficacy of an HPV vaccine in clinical practice. J. Med. Virol. 81:529–535, 2009. © 2009 Wiley‐Liss, Inc.     

Multiple human papilloma virus types in cervical infections: competition or synergy?

Mejlhede N, Pedersen BV, Frisch M, Fomsgaard A. Multiple human papilloma virus types in cervical infections: competition or synergy? APMIS 2010; 118: 346–52. Coinfection with multiple human papilloma virus (HPV) types is common in cervical HPV infection. To evaluate if infections with different HPV types occur independently, we examined 3558 women above 15 years of age suspected of cervical HPV infection. Among them, 1842 (52%) women were HPV negative and 1716 (48%) were HPV positive as analysed by a PCR‐based commercial microarray assay for mucosal types. Of the HPV‐positive samples, 824 (48%) had single infections, while 892 (52%) had multiple infections. Observed numbers of concurrent HPV types differed from expected numbers under the assumption of independence between infections by the various HPV types. Significant positive associations were observed for 16 pairs of HPV types in statistical analysis accounting for mass significance. Significant negative associations were also found, i.e. women with HPV‐16 infection had 0.4 times the odds of having HPV‐51 compared with women not infected with HPV‐16. HPV‐16 was the only type with odds ratios <1 for all pairwise combinations. While our findings of statistically significant coexistence do not prove biological dependence among HPV types, they do suggest that infections with some HPV types may depend on the existence of certain other HPV types. Any interaction between coexisting HPV types could either decrease or increase the efficacy of current HPV vaccines that offer mainly type‐specific protection, depending on whether the types vaccinated against compete with other HPV types or not.     

Type‐specific human papillomavirus prevalence in cervical intraepithelial neoplasia and cancer in Iran

In Iran, human papillomavirus (HPV) vaccination is not currently included in the national vaccination program and there are no comprehensive approaches to cervical screening program. Regional data on distribution of HPV types in women is important to predict the impact of current HPV vaccines. Although several studies on distribution of HPV types in cervical precancer and cancer have been conducted in Iran, in most of them HPV positive samples were subjected to specific‐primer genotyping (mainly 16 and 18), and leaving the other HPV genotypes almost undetermined. Therefore, the present study aimed to investigate the distribution of HPV types in cervical neoplasia from West and Northwest of Iran. A total of 112 women with atypia, cervical intraepithelial neoplasia, and invasive cervical cancer were included. A PCR assay was performed in all samples to detect the presence of the HPV genome using the GP5+/6+ L1 consensus primer set. All HPV positive samples were subjected for sequencing. In overall, HPV prevalence was 20% in atypica, 44.5% in cervical intraepithelial neoplasia I, 92.3% in cervical intraepithelial neoplasia II‐III, and 98.2% in invasive cervical cancer. The most frequent HPV type was HPV 16 (79.2%), which was followed by HPV types 18, 6, and 33 at the frequencies of 6.5%, 5.1%, and 2.7%, respectively. The least HPV types were found to be 31, 45, 53, 58, and 66. In conclusion, this study shows that the current HPV vaccines could have great impact to reduce the burden of cervical cancer in Iran.     

Prevalence of human papillomavirus genotypes in northern Taiwanese women

The prevalence of Human Papillomavirus (HPV) in the general population of northern Taiwan is described. A total of 343 consecutive cervical swabs from women visiting the medical center for routine gynecologic care were included. Cervical cell cytology was examined by the Papanicolaou (Pap) test, and a PCR‐based hybridization gene chip analysis was used to identify HPV genotypes. The HPV prevalence in the overall population was 32.4%. When divided into two groups according to cytology, 20.9% of women with normal cytology were HPV positive while 75.3% of women with abnormal cytology were HPV positive. Among positive samples, 68.5% were single type infections while 31.5% harbored multiple HPV types. A total of 32 types of HPV were identified; the leading five were HPV16 (5.8%), HPV58 (5.3%), HPV53 (4.1%), HPV52 (3.8%), and HPV18 (2.3%). Our results constitute baseline data and may provide important implications for future prophylactic programs. The relatively high prevalence of HPV 58, 53, and 52 among northern Taiwanese women has important implications for vaccine development. J. Med. Virol. 82:1739–1745, 2010. © 2010 Wiley‐Liss, Inc.     

Testing of a new probe 16/18/45 Hybrid Capture (Digene) in women with high risk HPV infection

BACKGROUND: HPV HR detection test are needed when ASCUS is diagnosed on Pap test. The risk of progression to cervical cancer is dependant on the HPV genotype and three types (HPV 16, 18 and 45) are found in 77.4% of the cervical cancer. Here we have tested a new probe 16/18/45 (Digene) that is able to detect specifically these three types. MATERIAL AND METHODS: Thirty-seven women with a Hybrid Capture 2 High Risk test (Digene) positive were selected to test the new probe 16/18/45. Samples were typed using sequencing reaction after GP5+/GP6+ PCR. Types were given after comparison with the GenBank. Discordant results were controlled with Inno-Lipa HPV genotyping v2 test (Innogenetics). RESULTS: Among the 37 women with HR HPV result, 48.6% were positive with the probe 16/18/45 (18 patients). After genotyping, 12 results were concordant and six discordant (three HPV 31, two HPV 58 et one HPV 59). For the other 19 patients with negative result, 18 are concordant and one discordant (HPV 18). Global concordance for typing between this probe and sequencing was 81% with a kappa test of 0.62 that means a good concordance. Positive predictive value is 66.6% and negative predictive value is 94.7%. CONCLUSION: This study shows a good efficiency of the 16/18/45 probe to detect the genotypes that have the higher risk of progression to cervical cancer. This probe could also allow to follow the epidemiology of HR HPV infection after a large use of HPV vaccines.     

Distribution of human papillomavirus genotypes among cervical intraepithelial neoplasia and invasive cancers in Macao

Macao is a densely populated city situated in East Asia where a relatively high prevalence of human papillomavirus (HPV) types 52 and 58 has been reported in women with invasive cervical cancer. To provide data for a population‐specific estimation on the impact of HPV vaccines, paraffin‐embedded tissues collected from women with invasive cervical cancer or cervical intrapeitheilal neoplasia grade 2 or 3 confirmed histologically were examined for HPV using the INNO‐LiPa kit. Of the 35 HPV‐positive patients with invasive cancer, one HPV type was detected in 68.6%, and 31.4% were co‐infected with more than one HPV type. Overall, HPV 16, HPV 18, HPV 52, and HPV 54 were the most common types found respectively in 57.1%, 17%, 11.4%, and 8.5% of patients with invasive cervical cancer. Among the 59 HPV‐positive patients with cervical intraepithelial neoplasia grade 2/3, 55.9% hardbored one HPV type, and 44.1% had co‐infections. The common HPV types found included HPV 16 (52.5%), HPV 52 (23.7%), HPV 58 (18.7%), and HPV 33 (17%). Although HPV 11 (a low‐risk type) was also found commonly in invasive cervical cancers (14.3%) and cervical intraepithelial neoplasia grade 2/3 (15.3%), the fact that they all existed as co‐infections with another high‐risk type suggested HPV 11 was not the cause of the lesion. The current vaccines targeting HPV 16/18 are expected to cover 62.9–74.3% of invasive cervical cancers and 32.2–55.9% of cervical intraepithelial neoplasia 2/3 in Macao. Widespread HPV vaccination is expected to reduce substantially the disease burden associated with cervical neoplasia in Macao. J. Med. Virol. 82:1600–1605, 2010. © 2010 Wiley‐Liss, Inc.     

Prevalence of HPV cervical infection in a family planning clinic determined by polymerase chain reaction and dot blot hybridisation

The overall prevalence of human papillomavirus (HPV) cervical infection in 131 women attending a family planning clinic was 7% (HPV 6/11, 16, 18, 31) by dot blot hybridisation, 53% (HPV 11, 16, 31) by polymerase chain reaction (PCR), and 56% by the two methods combined. HPV 16 and 18 were the commonest types (4% each) by dot blot, HPV 16 (39%) by PCR. Fifteen percent of subjects had mildly abnormal cervical cytology (grades 1A, 2A, or 3). There was no significant correlation between cytological abnormality and HPV positivity, or between cytological or HPV status and other postulated risk factors for cervical neoplasia. It is concluded that PCR is considerably more sensitive than dot blot DNA hybridisation in detecting HPV cervical infection in such a "low risk" setting, where HPV copy number may be low. Firm conclusions cannot be drawn from our results regarding a causal role for HPV or other factors in the development of cervical neoplasia.     

Prevalence of human papillomavirus in women attending cervical screening in the UK and Ireland: New data from northern Ireland and a systematic review and meta‐analysis

There is substantial international variation in human papillomavirus (HPV) prevalence; this study details the first report from Northern Ireland and additionally provides a systematic review and meta‐analysis pooling the prevalence of high‐risk (HR‐HPV) subtypes among women with normal cytology in the UK and Ireland. Between February and December 2009, routine liquid based cytology (LBC) samples were collected for HPV detection (Roche Cobas® 4800 [PCR]) among unselected women attending for cervical cytology testing. Four electronic databases, including MEDLINE, were then searched from their inception till April 2011. A random effects meta‐analysis was used to calculate a pooled HR‐HPV prevalence and associated 95% confidence intervals (CI). 5,712 women, mean age 39 years (±SD 11.9 years; range 20–64 years), were included in the analysis, of which 5,068 (88.7%), 417 (7.3%) and 72 (1.3%) had normal, low, and high‐grade cytological findings, respectively. Crude HR‐HPV prevalence was 13.2% (95% CI, 12.7–13.7) among women with normal cytology and increased with cytological grade. In meta‐analysis the pooled HR‐HPV prevalence among those with normal cytology was 0.12 (95% CIs, 0.10–0.14; 21 studies) with the highest prevalence in younger women. HPV 16 and HPV 18 specific estimates were 0.03 (95% CI, 0.02–0.05) and 0.01 (95% CI, 0.01–0.02), respectively. The findings of this Northern Ireland study and meta‐analysis verify the prevalent nature of HPV infection among younger women. Reporting of the type‐specific prevalence of HPV infection is relevant for evaluating the impact of future HPV immunization initiatives, particularly against HR‐HPV types other than HPV 16 and 18. J. Med. Virol. 85:295–308, 2013. © 2012 Wiley Periodicals, Inc.     

Distribution of human papillomavirus genotypes in cervical intraepithelial neoplasia and invasive cervical cancer in Canada

Infection with high‐risk human papillomavirus (HPV) causes cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC). The distribution of HPV types in cervical diseases has been previously described in small studies for Canadian women. The prevalence of 36 HPV genotypes in 873 women with CIN and 252 women with ICC was assessed on cervical exfoliated cells analyzed with the Linear Array (Roche Molecular System). HPV16 was the most common genotype in CIN and ICC. The seven most frequent genotypes in order of decreasing frequency were HPV16, 51, 52, 31, 39, 18, and 56 in women with CIN1, HPV16, 52, 31, 18, 51, 39, and 33 in women with CIN2, HPV16, 31, 18, 52, 39, 33, and 58 in women with CIN3, and HPV16, 18, 45, 33, 31, 39, and 53 in women with ICC. HPV18 was detected more frequently in adenocarcinoma than squamous cell carcinoma (P = 0.013). Adjustment for multiple type infections resulted in a lower percentage attribution in CIN of HPV types other than 16 or 18. The proportion of samples containing at least one oncogenic type was greater in CIN2 (98.4%) or CIN3 (100%) than in CIN1 (80.1%; P < 0.001 for each comparison). Multiple type infections were demonstrated in 51 (20.2%) of 252 ICC in contrast to 146 (61.3%) of 238 women with CIN3 (P < 0.001). Adjusting for multiple HPV types, HPV16 accounted for 52.1% and HPV18 for 18.1% of ICCs, for a total of 70.2%. Current HPV vaccines should protect against HPV types responsible for 70% of ICCs in Canadian women. J. Med. Virol. 83:1034–1041, 2011. © 2011 Wiley‐Liss, Inc.     

Prevalence and genotype distribution of human papillomavirus in non-neoplastic cervical tissue lesion: cervical erosion

Human papillomavirus (HPV) infection is the commonest sexually transmitted infection, which is associated with various clinical conditions, ranging from asymptomatic infection to malignant disease of the cervix. The aim of this study was to evaluate the prevalence and genotypic distribution of HPV in women with cervical erosion and to compare the results with those in women with a clinically normal cervix. A further aim was to establish the association between HPV infection and cervical cytology results in women with and without cervical erosion. Cervical samples were collected by liquid-based method and consecutively evaluated for the presence of HPV DNA and for cervical cytology. HPV DNA was tested by a nested polymerase chain reaction (PCR) and typed by reverse dot blot genotyping. Cytological classification was made according to Bethesda 2001 criteria. The overall HPV prevalence was 16.9%; HPV DNA was positive in 20.2% of women with cervical erosion and 12.8% in women with normal cervix (P < 0.05). Multiple infections were found in 34.1% of the HPV-positive women. Commonest types were HPV 18 (32.9%), HPV 16 (29.5%), HPV 54 (20.5%), and HPV 6 (17%). Cervical cytology results were abnormal for 5.2% of women with cervical erosion and for 1.3% with clinically normal cervix (P < 0.05). This study detected a high prevalence of HPV infection in women with cervical erosion compared to women with a normal cervix. This data may contribute to the HPV epidemiology in the southeastern Turkey. It is recommended that women with cervical erosion should be given priority in HPV screening programs.     

Prevalence and genotype distribution of human papillomavirus infection of the cervix in Spain: the CLEOPATRE study

Human papillomavirus (HPV) infection is a necessary cause of cervical cancer. The aim of this study was to estimate the prevalence of cervical HPV infection and HPV type-specific distribution among women attending cervical cancer screening in Spain during 2007 and 2008. Women aged 18-65 years were recruited according to an age-stratified sampling method. Liquid-based cervical samples were collected and analyzed for cytology, HPV detection, and genotyping. HPV genotyping was determined using the INNO-LiPA HPV Genotyping Extra Reverse Hybridization Line Probe Assay. Prevalence estimates were age-standardized using 2001 Spanish census data. The present study included 3,261 women. Age-standardized HC2-based HPV prevalence was 14.3% (95% CI, 13.1-15.5) among women aged 18-65 years, and 28.8% (26.6-31.1) among women aged 18-25 years. High-risk HPV types were detected in 12.2% (95% CI, 11.1-13.4) of HPV-tested women, representing 84.0% of HPV-positive samples. Multiple infections were present in 4.1% (95% CI, 3.4-4.8) of HPV-tested women (25.0% of HPV-positive samples). The most common high-risk HPV-types among HPV-tested women were 16 (2.9%), 52 (1.8%), 51 (1.6%), 31 (1.3%), and 66 (1.2%). HPV-type 16 was present in 16.9% of HPV-positive samples. One or more of the HPV vaccine types 6/11/16/18 were detected in 3.8% of HPV-tested women (22.1% of HPV-positive samples). Though not a true population-based survey, this study provides valuable baseline data for future assessment of the impact of current HPV vaccination programs in Spain. The high prevalence of HPV infection among young women may reflect recent changes in sexual behavior.     

Evaluation of type-specific HPV persistence and high-risk HPV viral load quantitation in HPV positive women under 30 with normal cervical cytology

The persistence of high-risk HPV (HR-HPV) infection is necessary for the development of cervical intraepithelial neoplasia. The aim of this study was to evaluate if HR-HPV typing and HPV16, 18, 31, and 33 quantitation are predictive for type-specific infection persistence and/or the development of CIN in women under 30 with normal cervical cytology. Young women (under 30) attending a family planning clinic who were HPV positive with normal cervical cytology were included. HPV genotyping was assessed by MY09/MY11 PCR, sequencing, phylogenetic analysis, and cloning when necessary. HR-HPV viral load was quantified using duplex real-time PCR. Study patients were offered for a second smear and HR-HPV detection and quantitation after 12 months. HR-HPV was identified in 43 (21.9%) of the 199 included women. Of these, 39 patients had a second cervical sample taken within a mean interval of 11.7 months (8.8-18.3 months). The mean HR-HPV 16, 18, 31, and 33 initial viral load was 1.9 × 10(6) copies/million cells. The level of viral load did not reveal any significant association with type-specific HR-HPV persistence or the subsequent development of cervical intraepithelial neoplasia. Only HPV16 infection was significantly more likely to persist (91.7% vs. 33.1%, P=0.001) and to develop CIN (33.3% vs. 3.7%, P=0.025). In women under 30 with normal cytology, HR-HPV viral load is common and is not predictive of HPV persistence or the development of cervical intraepithelial neoplasia. HPV16 positive women are significantly more likely to have persistent infection and to develop cervical intraepithelial neoplasia.     

Human Papillomavirus Prevalence and Genotype Distribution among HIV-Infected Women in Korea

The epidemiology on human papillomavirus (HPV) among human immunodeficiency virus (HIV)-infected women in Korea is not well established. A retrospective study was conducted to determine the prevalence and genotype distribution of HPV infection among HIV-infected women in Korea. HPV DNA genotype and cervical cytology were examined in 60 HIV-positive women and 1,938 HIV-negative women. HPV genotypes were analyzed by using a HPV DNA chip. HIV-infected women had higher prevalence of high-risk HPV (hr-HPV) infection (30% vs 4.9%, adjusted odds ratio [AOR], 6.96; 95% confidence interval [CI], 3.63-13.34, P<0.001) and abnormal cervical cytology (18.3% vs 1.8%, AOR, 10.94; 95% CI, 5.18-23.1, P<0.001) compared with controls. The most common hr-HPV genotype detected in HIV-infected women was HPV 16 (10%), followed by 18 (6.7%) and 52 (5%). Prevalence of quadrivalent vaccine-preventable types (HPV 6, 11, 16, and 18) was 21.7% and 2.3% in HIV-positive women and HIV-negative women, respectively. Age was a significant risk factor for hr-HPV infection in HIV-infected women (P=0.039). The presence of hr-HPV was significantly associated with abnormal cervical cytology (P<0.001). These findings suggest that HPV testing for cervical cancer screening in HIV-infected women would be necessary, particularly among young age group.     

The prevalence of HPV infections in HPV‐vaccinated women from the general population

Currently, three prophylactic HPV vaccines are commercially available to prevent HPV 16/18 infection and associated lesions. The aim of the study was to assess markers of HPV infection in women/girls before vaccination and to ascertain the prevalence and spectrum of post‐vaccination HPV types. Three hundred and thirty subjects of which 75 were virgins were enrolled. Before the first dose of the HPV vaccine and 1, 3 and 5 years after the completion of HPV vaccination, the samples for cytology, HPV detection and anti‐HPV antibody response were taken. At enrolment, HPV DNA was detected in 38% of sexually active girls/women. At the first, second and third follow‐up, HPV DNA was found in 40, 45, and 39% of them. The seroprevalence rates to HPV 6, 11, 16 and 18 in these subjects were 31, 21, 18 and 10%. On the follow‐up significantly higher levels of antibodies to HPV 16/18 were found after application of divalent vaccine. Results of the study demonstrate high prevalence of HPV infection in young women. In a substantial number of women, HPV‐specific antibodies as well as high‐risk HPV types were detected. HPV‐specific antibodies were also frequently found in non‐sexually active girls. The acquisition of HPV after the onset of sexual life was very fast.     

Prevalence of human papillomavirus types 6, 11, 16, 18, 31, and 33 in a cohort of Greek women

To study HPV prevalence and HPV types 6, 11, 16, 18, 31, and 33 distribution in cervical smears in a cohort of Greek women. One thousand six hundred thirty-six samples were cytologically evaluated and molecularly analyzed, by PCR based assay. Abnormal cytology was identified in 997 women and 75.4% of them were HPV DNA positive, while 639 had normal cytology and 24.6% were HPV DNA positive. HPV was detected in 62.9% of 256 ASCUS smears, 89.3% of 516 LSIL, 86.7% of 60 HSIL and 47.3% of 165 with cervical carcinoma. Overall, HPV 11 was the most common type (13.4%), followed by 18 (10.3%), 6 (7.2%), 16 (6.4%), 31 (3.4%) and 33 (3.4%). Multiple infections with two (11.3%) or more types, primarily 11 and 18 (4.8%), were also identified. Low-risk types 11 and 6 were common in ASCUS (36.6% and 26.4%, respectively), and high-risk types 16 and 18 in HSIL (42.3% and 30.8%, respectively) and in cancer (51.3% and 41%, respectively). Multiple infections were detected in 2.2% of normal and 31.7% of HSIL. HPV prevalence was 75.4% in abnormal and 24.6% in normal cervical smears. HPV 16 and 18 were the most common types in cancer. Single infection with type 11 and multiple infections with 11 and 18 were more frequent.     

Prevalence and genotype distribution of human papillomavirus infection in Harbin,Northeast China

This study aimed to investigate the overall prevalence of human papillomavirus (HPV) infection among women examined at a hospital in Harbin and to evaluate the impact of HPV types on the natural outcome and state of cervical cytology. A total of 2,938 female outpatients from the affiliated hospital of Harbin Medical University were enrolled. Rapid hybridization gene chip and liquid-based cytology tests were used to detect HPV genotypes and cervical cytology. The overall prevalence of HPV in women who came to this hospital was 36.45 %. The majority were infected with a single strain, and the high-risk HPV (HR-HPV) type constituted the largest proportion. HPV16 and 58 were the most common types, while the genotypes of single low-risk HPV (LR-HPV) were not the same in different age groups. HPV53, 16 and 81 were the most common types in multiple HR-HPV infection; HR-HPV16, 33, 81 and LR-HPV 6, 44, 43 were the most common in HR and LR-HPV infection. In total, 44.1 % of the women with HSIL and 44.0 % with ASCUS were positive for HR-HPV16. Multiple HPV infections and single HPV infections had no effect on the natural outcome after half a year. HPV16, 81 and 35 had a better natural outcome, followed by HPV52 and 53, but HPV58, 59 and 18 had a bad outcome after half a year. This is the first study to show that the distribution of HPV types is different in Harbin than it is in other regions. These findings will provide guidance for the vaccination program in this area.     

Detection of HPV types and neutralizing antibodies in Gansu province,China

A total of 82 samples from patients with cervical cancer (Group 1) and 50 samples from patients with other genital diseases (Group 2) were collected in Gansu, China. All 132 samples were tested for HPV DNA with a typing kit that can detect 21 types of HPV, and also tested for neutralizing antibodies against HPV‐16, ‐18, ‐58, ‐45, ‐6, and ‐11 using pseudovirus‐based neutralization assays. The results revealed that 28% (23/82) of sera in Group 1 were positive for type‐specific neutralizing antibodies with a titer range of 160–640, of which 23.2% (19/82), 2.4% (2/82), 2.4% (2/82), 1.2% (1/82), and 1.2% (1/82) were against HPV‐16, ‐58, ‐6, ‐18, and ‐45, respectively. Only one serum (2%) in Group 2 was positive for neutralizing antibodies, which were against HPV‐6 with a titer of 2,560. Overall, 85.4% (70/82) of samples in Group 1 were HPV DNA‐positive, compared with 28% (14/50) of samples in Group 2. The seven most common types detected in Group 1 were HPV‐16 (80%), HPV‐52 (7.1%), HPV‐66 and HPV‐11 (5.7% each), and HPV‐58, HPV‐18, and HPV‐33 (4.3% each), while the four most common types in Group 2 were HPV‐16 (12%), HPV‐52 and HPV‐11 (6% each), and HPV‐68 (4%). The concordance between HPV DNA and corresponding neutralizing antibodies was 32.9% (27/82) with a significant difference (P < 0.005). More specifically, the concordance was 42.7% (35/82) for HPV‐16 in Group 1. The full‐length sequences of six HPV types (HPV‐16, ‐58, ‐33, ‐59, ‐11, and ‐68) were determined and showed 99% identities with their reported genomes. J. Med. Virol. 81:693–702, 2009 © 2009 Wiley‐Liss, Inc.