Vaccine
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Non-typhoid Salmonella (NTS) is a leading cause of food-borne illness with more than 90 million annual cases and an emerging antimicrobial resistance among the strains worldwide. Paradoxically, no vaccines are available against these pathogens. Numerous NTS strains share surface O-antigens with Salmonella enterica serotype Typhi. As intestinal antibodies against O-antigens have proven protective against NTS in animal experiments, it appears conceivable that the oral whole-cell typhoid vaccine, Salmonella Typhi Ty21a (Vivotif(®)), which effectively elicits intestinal antibodies against O-antigens, could exhibit cross-protective efficacy against NTS. We sought immunological evidence in support of cross-protective efficacy of Ty21a against NTS. ⋯ Intestinal antibodies against O-antigens protect against NTS in animal experiments. Ty21a was found to elicit intestinal immune responses cross-reactive with NTS strains sharing O-antigens with Ty21a. These include the most common NTS, Salmonella Enteritidis and Typhimurium. The data suggest that Ty21a may have cross-protective efficacy against numerous NTS strains.
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The majority of industrialized and some developing countries have established technical advisory bodies to guide and formulate national immunization policies and strategies. These are referred to as National Immunization Technical Advisory Groups (NITAGs), WHO and its partners have placed a high priority on assisting in the establishment or strengthening of functional, sustainable, and independent NITAGs. To enable systematic global monitoring of the existence and functionality of NITAGs, in 2010, WHO and UNICEF included related questions in the WHO-UNICEF Joint Reporting Form (JRF) that provides an official means for WHO and UNICEF to collect indicators of immunization programme performance. ⋯ Impressive progress has been observed in the proportion of countries reporting NITAGs with formal terms of reference (24% increase), a legislative or administrative basis (10% increase), and a requirement for members to disclose their interests (14% increase). Some of the poorest developing countries now enjoy support from a NITAG which meet all six process indicators. These may serve as examples for other countries.
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The worldwide prevalence of infection with human papillomavirus (HPV) in women without cervical abnormalities is 11-12% with higher rates in sub-Saharan Africa (24%), Eastern Europe (21%) and Latin America (16%). The two most prevalent types are HPV16 (3.2%) and HPV18 (1.4%). Prevalence increases in women with cervical pathology in proportion to the severity of the lesion reaching around 90% in women with grade 3 cervical intraepithelial neoplasia and invasive cancer. ⋯ Genital warts represent a sexually transmitted benign condition caused by HPV infection, especially HPV6 and HPV11. Reliable surveillance figures are difficult to obtain but data from developed countries indicate an annual incidence of 0.1 to 0.2% with a peak occurring at teenage and young adult ages. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.
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The reframed paradigm of cervical cancer prevention will include strategic combinations of at least four major components: 1) routine introduction of human papillomavirus (HPV) vaccines to women in all countries, 2) extension and simplification of existing screening programs using HPV-based technology, 3) extension of adapted screening programs to developing populations, and 4) consideration of the broader spectrum of cancers and other diseases preventable by HPV vaccination in women, as well as in men. On a global scale, vaccination of newborns and infants is well established and has developed a successful working infrastructure. The hepatitis B virus (HBV) vaccination programs offer a model for HPV introduction in which newborn and infant immunization achieves a rapid reduction in the prevalence of the HBV carrier rates in immunized cohorts of children, and of liver cirrhosis and liver cancer decades later. ⋯ Significant political and advocacy efforts at the Global level (World Health Organization, other United Nations agencies and The GAVI Alliance) need to be organized and reinforced to achieve a meaningful reduction in HPV transmission and its related health conditions and cancers. This desirable goal is now scientifically and technologically attainable, and great progress is being made in obtaining financing for global HPV immunization. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.
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The availability of prophylactic human papillomavirus (HPV) vaccines has provided powerful tools for primary prevention of cervical cancer and other HPV-associated diseases. Since 2006, the quadrivalent and bivalent vaccines have each been licensed in over 100 countries. By the beginning of 2012, HPV vaccine had been introduced into national immunization programs in at least 40 countries. ⋯ In the 5 years since HPV vaccines were licensed, there have been successes as well as challenges with vaccine introduction and implementation. Further progress is anticipated in the coming years, especially in low- and middle-income countries where the need for vaccine is greatest. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.