Generating epidemiological, economic and attitudinal evidence to inform policy-making about HPV vaccine introduction in India and Ethiopia

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Human Papilloma Virus (HPV) is a virus found throughout the world. The virus is transmitted between humans, mainly by sexual contact. Cancer of the cervix is the second most common cause of cancer in most parts of the world. Almost all cases are caused by HPV. HPV also causes rarer genital and oral cancers in males and females. There are many types of HPV, but two types (16 and 18) are responsible for most (about 70%) of cancer cases throughout the world. Since 2006 two vaccines have been available that can prevent infection by types 16 and 18. In UK one of the vaccines was introduced into the national program in 2008, given to girls 12-13 years of age. Most industrialised countries now use the vaccine for girls, some also vaccinate boys. There are 3 types of vaccine available covering 2, 4 and 9 types of HPV. The burden of cervical cancer is highest in developing countries, partly for sociological reasons, and partly because few developing countries have cervical screening (Pap smear) programs that detect and treat early stages of cancer, reducing the number of cases that progress to clinical cancer. Vaccination could prevent most of these cases, but up to now HPV vaccine use in developing countries has been very limited because of the high price of the vaccine. In addition, because the vaccine is given to girls in early adolescence, fears have been expressed in some quarters about the safety and the effectiveness of the vaccines. Between India and Ethiopia it is estimated that 40% of all cervical cancers occur in these two countries. In India the vaccine has been used on a limited scale, based on decisions taken by local authorities. Some areas of India have high cervical cancer risk, while others have lower risk. By measuring the proportions of young women who are infected with high risk HPV types, and also measuring the patterns of sexual behaviour, we will develop a simple way by which Indian authorities can estimate the risk level in their communities, and therefore prioritise HPV vaccine introduction. We will also study the other types of HPV circulating to help the government decide on which vaccine to use. To help with vaccine decision making we will also measure the cost of cervical cancer, both in monetary and in human terms. We will investigate these issues by interviewing newly diagnosed cases, as well as conducting interviews with the families of deceased cases. To demonstrate that the vaccine actually works in India we will follow a group of young vaccinated women in the Punjab state where the HPV vaccine is being used. We expect that in future researchers will be able to show a greatly reduced number of infections in these girls. In Ethiopia, cervical cancer is common, but as there are no cancer registries it is not possible to say how common. The government has undertaken a pilot vaccination program in 2 areas of the country, Jimma in the south, and Mekelle in the north. We will measure how common HPV infection is in these areas. Then we will follow 2000 girls who have been vaccinated, and a similar number of unvaccinated girls, yearly to record sexual behaviour and to measure how many have been infected. This will provide the government and the community with proof of the effectiveness of the vaccine, enabling them to accelerate the introduction of the vaccine and to maintain vaccine coverage. To support this studies of the true cost of cervical cancer will be conducted along similar lines to the studies in India. During the course of this study we will evaluate the HPV laboratory in Vellore, India. That laboratory will be used for all Indian and many Ethiopian samples. During the study the laboratory techniques will also be taught to two Ethiopian scientists, after which they will establish a HPV laboratory in Ethiopia.