FEATURE OBS/GYNE
FIGURE 1: Age-standardised incidence and mortality rates, cervical cancer by region of the world. Courtesy of Cancer Research UK
Eastern Africa Southern Africa Caribbean
Central America Western Africa South America Middle Africa
South Central Asia South Eastern Asia World
Eastern Europe Northern Africa Southern Europe Western Europe Northern Europe Northern America Eastern Asia
Australia/New Zealand Western Asia
0 10 20 30 40 Rate per 100,000 population
TABLE 1: BARRIERS TO SCREENING AND VACCINATION Barrier
Competing health needs
Limited financial and human resources
Poorly developed healthcare resources
Women are uneducated and disempowered
War and civil strife Widespread poverty The nature of the screening test
Healthcare priorities e.g. maternal mortality, HIV competing for shrinking healthcare budget
Limited healthcare professionals and health facilities
32 of the 53 countries in Africa have no radiotherapy services, nor any prevention, screening, early diagnosis or end-of-life care program
Poor healthcare access, health-seeking behaviour, and ability to generate income
Displacement of people, the creation of refugees, disruption of healthcare services, with subsequent loss of infrastructure and personnel and the diversion of state money to defence
Limited access to safe water, health services
Limited infrastructure, high quality laboratories, skilled healthcare professionals
and parts of Latin America, colposcopy is incorporated into the routine gynaecological examination of women. There are no data to support the use of colposcopy as a primary screening test and this is not generally recommended. A cost-effective model for five
developing countries which included Kenya and South Africa showed that screening with one-visit or two-visits in a lifetime using visual inspection or HPV DNA test coupled with immediate cryotherapy for screened positives for women aged 35 years or older, has the potential to reduce the lifetime risk of
cancer by 25–35% compared with no screening, and cost less than 500 dollars per year of life saved. Relative cancer risk declined by an additional 40% with two screenings at 35 and 40 years of age, resulting in a cost per year of life saved that was less than each country’s per capita GDP. In Africa, where minimal cervical screening services are available, this once in a lifetime screen-and-treat strategy may have an important impact in reducing the incidence of cervical cancer and needs to be evaluated locally to determine whether it is logistically feasible, acceptable and safe.
50
VACCINATION Prophylactic HPV vaccines give new promises for a primary prevention strategy for HPV infection and cervical cancer. The HPV vaccines have shown 95% efficacy in preventing vaccine HPV types and related precancerous lesions for up to seven years in large international cohorts of women. The vaccines have shown high safety, efficacy and immunogenicity for both the quadrivalent HPV 16⁄18⁄6⁄11 vaccine (GardasilÒ, Merck & Co., Inc.) and the bivalent HPV 16⁄18 vaccine (Cervarix, GlaxoSmithKline Biologicals). A number of countries in Africa have
Incidence Mortality
licensed the HPV vaccines. However, implementation plans are lagging and will depend largely on the affordability of the vaccines, and a clear cost/benefit ratio. In addition, protecting women against the virus requires vaccinating young women aged 10-12 three times in six months. This presents a unique challenge in Africa, where girls of this age may not be in school, where immunization is easiest. Since first-generation vaccines will target young adolescents, it will take several decades to determine the effect of these vaccines on the rate of death from cervical cancer. Even then, since current vaccines target only two types of oncogenic HPV, a combination of screening and vaccination will probably be required. Consequently, timely implementation of a cost-effective screening strategy for use in developing countries is particularly critical (see table 2).
CONCLUSION Cervical cancer is a preventable and treatable cancer. The introduction of HPV vaccines offers exciting options for cervical cancer prevention. However, until these vaccines become widely available and affordable for Africa, feasible screening strategies remain the primary prevention strategy. The availability of low cost cervical screening methods such as HPV-DNA testing and visual inspection methods represent tools that provide realistic opportunities for cervical cancer prevention in Africa. ■
AH LEARN MORE
Africa Health Exhibition was a huge success back in May. With 35% of exhibition space re-booked already, the event is set to be even bigger next year. For more information, visit us at:
www.africahealthexhibition.com
Arab Health Issue 3 2011 23
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64