In China, the attribution of HPV52/58 is significantly higher than elsewhere. China's medical resources are concentrated in tertiary hospitals, where bearing “HPV-heavy-burden”, which can provide representative samples to delineates a national comprehensive landscape of the prevalence and multi-infection patterns of HPV among gynecological outpatients (GOP), and to evaluate the cross-protective efficacy of HPV16/18 vaccine.
We recruited participants out of GOP from 8 tertiary hospitals in 7 provinces of China. Cervical exfoliated cell samples were collected for HPV genotyping using Tellgenplex™ HPV DNA Assay. Odds ratio was used for the evaluation of the preference of any two types co-infection (AB): the real infection rate of AB divided by it's theoretical rate (the multiplication of the single infection rate of A and B).
Among 137,949 samples from GOP, the total prevalence of 27 HPVs (17hr/10lr) was 23.5%. Age-specific prevalence showed a flat “U-formed” pattern. The most prevalent hrHPVs were all from α9:16(3.3%), 52 (2.3%), 58 (1.9%). The most prevalent lrHPVs were both from α3: 81(0.9%), 61(0.9%). Overall, the prevalence of 6 and 11 were 0.6% and 0.3%, which differed by geographic region and decreased with age. Multi-infection was identified in 25.8%. The two-types-infection was predominant. We found that 15% of hrHPV infections were co-infected with lrHPV; while 40% lrHPV infections were co-infected with hrHPV. HPV16 consisted of 66.51% single infection, the highest, followed by 52(60.2%), 58(59.81%), while 26(33.3%) as the lowest. The mixed genotypes 16+58(283) and 16+52(265), 52+58(242), 16+18(195) were the most common multi-infections. The co-infection (AB) preference pattern of 13 hrHPVs to 16 was 31(3.4), 45(2.8), 33(2.7), 35(2.4), 18(2.3), 56(2.0), 59(1.8), 58(1.7), 39(1.7), 66(1.7), 51(1.6), 68(1.3), 52(1.2). The co-infection (AB) preference pattern of 13 hrHPVs to 18 was 31(3.9), 35(3.0), 56(2.7), 51(2.7), 33(2.6), 66(2.5), 59(2.4), 58(1.6), 39(2.2), 45(2.0), 52(1.7), 58(1.6), 68(0.7). This analysis revealed that HPV31 was the most involved in HPV 16/18 co-infection, while HPV52/58 had less co-infection preference to HPV16/18.
These co-infection (AB) preference patterns are highly consistent with cross-protective efficacy of HPV16/18 vaccine against HPV31, but almost negative vaccine efficacy against HPV52/58. On one side, this finding may explore the mechanism of cross-protection of HPV vaccines. On another side, it indicates that it is urgently needed to evaluate the efficacy of HPV vaccines and the influences to the HPV epidemic in China, where with high prevalence of HPV52/58 as the current vaccines only covering HPV16/18.
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