Presence of infection and analysis of HPV subtypes in girls younger than 9 years old attended at a referral service in Espírito Santo, Brazil

Abstract

Human papillomavirus (HPV) is found in adults and adolescents and is associated with genital warts and cervical cancer. However, it has been detected in girls younger than 10 years old. Currently, there are no prevention methods for this age group, since it is not considered a risk group. The aim of this study was to evaluate the presence of infection and HPV subtype in girls under 9 years old attended at a referral service in the State of Espírito Santo, Brazil. Forty-three girls younger than 9 years old had gynecological brush samples collected from vulval and perineal/anal regions. Viral detection and subtyping were done using polymerase chain reaction, restriction fragment length polymorphism and DNA sequencing. Statistics was performed using Action Stat 3.1. The mean age of girls was 6.1 years. Sexual activity and abuse were not reported by 95.3%. Family stories showed viral infection in 9.3% of mothers, 4.7% of fathers and 9.3% of caretakers. None of these were related with the children infection. In the only case of mother's gestational HPV infection, the daughter tested negative. Genital warts and infection were observed in 7% and 13.9% of the patients, respectively. Viral subtypes detected were 6, 11, 38, and 42. These results demonstrate the presence of HPV infection in girls under 9 years of age. Prevalence studies are needed in order to evaluate a possible alteration in age of vaccination policy.

Seroprevalence of HPV serotypes 6, 11, 16 and 18 in unvaccinated children from Mexico City

“…We wish to emphasise that the prevalence of antibodies among the children participating in our study may be considerably higher than values reported elsewhere [27, 28]. Also, our results showed that boys aged 9–14 years had a higher HPV18 seroprevalence than other studies.…”

“…A study conducted in Brazil reported the presence of high-risk HPV serotypes in girls and boys aged 10–15 years, with a seroprevalence of 9.3% for HPV-16 and 1.9% for HPV-18 [28]. …”

“…A study carried out in Germany, with a sample drawn from the general population, observed that the group under 15 years of age had a prevalence of antibodies against serotypes 16 and 18 of <3% for both genders [27]. A study conducted in Brazil reported the presence of high-risk HPV serotypes in girls and boys aged 10–15 years, with a seroprevalence of 9.3% for HPV-16 and 1.9% for HPV-18 [28].…”

Prevalence of human papillomavirus in oral rinse samples from healthy individuals in northern Thailand

“…However, HPV can certainly be acquired at an early age: One of 34 children (a male, aged 9), followed up after one year, was found positive for HPV18. Sartori et al also reported the presence of HPV infection in girls under 9 years of age. Acquisition of HPV at an early age supports the recommendation that HPV vaccination should be done at the age of 9.…”

Prevalence of human papillomavirus type 16 in persistent oral lesions arising in patients with tobacco, areca nut, and alcohol habits

“…The products of PCR amplification reactions, performed in triplicates on a T100 ™ Thermal Cycler (Bio‐Rad), were resolved on 2% agarose (0.5 µg/mL EtBr) horizontal gel electrophoresis using a 1X TAE buffer system, and DNA bands were visualized using an UV gel documentation system (AlphaImager HP System, Protein Simple). The presence of HPV viral DNA was assessed by conventional PCR using degenerate primers MY09 and MY11 (Table ) targeting the L1 gene (HPV species) in reaction mixture composing nuclease‐free water, Taq buffer (1X), MgCl 2 (1.5 mmol/L), dNTPs (0.2 mmol/L), primers (0.4 µmol/L), DNA (60 ng), and Taq polymerase (1 U); the thermocycling steps were as follows: (a) initial denaturation: 95°C for 5 minutes; (b) 40 cycles of denaturation (95°C for 1 minute), annealing (56°C for 1 minute) and extension (72°C for 1 minute); and (c) final extension: 72°C for 10 minutes. Subsequently, a nested PCR assay was carried out using GP05+ and GP06+ specific primers (Table ), targeting the L1 amplicons amplified using MY09/MY11, for confirming the presence of HPV DNA using the reaction mixes comprising nuclease‐free water, Taq buffer (1X), MgCl 2 (1.5 mmol/L), dNTPs (0.2 mmol/L), primers (0.4 µmol/L), Taq polymerase (1 U), and DNA template (5 µL amplification product of MY09/MY11); the thermocycling steps were as follows: (a) initial denaturation: 95°C for 5 minutes; (b) 40 cycles of denaturation (95°C for 1 minute), annealing (45°C for 1 minute) and extension (72°C for 1 minute); and (c) final extension: 72°C for 10 minutes.…”