A Study in Adolescent Females to Explore Cytomegalovirus Infection

Inclusion Criteria:

- A female adolescent between, and including 10 and 17 years at the time of enrolment
regardless of pregnancy status and contraception method used or not used.

- Subjects who the investigator believes that the subject and/or the subject's
parent(s)/Legally Acceptable Representative(s) (LAR[s]) can and will comply with the
requirements of the protocol.

- Written informed assent and/or consent obtained from the subject and/or the
parent(s)/LAR(s) of the subject.

- Subject is likely to remain in the area and/or return for required study Site Visits
and complete Sample Collection Visits.

Exclusion Criteria:

- Child in care.

- Use or planned use of any investigational or non-registered antiviral drug or vaccine
during the study period.

- Known medical history of any recurrent clinical herpes episodes requiring episodic or
chronic suppressive treatment with oral or parenteral antiviral treatment such as
acyclovir, famciclovir, valacyclovir or any other anti-herpes virus anti-viral during
the year preceding enrolment. Topical anti-viral are allowed.

- Subjects with history of previous vaccination against CMV.

- Chronic administration of immunosuppressants or other immune-modifying drugs within 6
months prior to Visit 1 or planned administration during the study. Inhaled and
topical steroids are allowed.

- Administration of immunoglobulins and/or any blood products within 3 months prior to
Visit 1 or planned administration during the study.

- Any confirmed or suspected immunosuppressive or immunodeficient condition including
HIV-infection, based on medical history and physical examination (no laboratory
testing required).

- Any major congenital defects, serious chronic illness or organ transplantation.