Immunization and child health in developing countries: Canada's response

According to a national poll conducted in 1999, Canadians considered vaccination to be the most valuable scientific breakthrough of the 20th century (1). Dr Edward Jenner discovered the first vaccine against smallpox in 1798; however, the vast majority of existing vaccines were released on the market in the latter half of the 20th century (2), thanks to the accelerated efforts in vaccine research and development by scientists such as Dr Jonas Salk, who discovered a vaccine against the crippling disease, poliomyelitis. Scientific endeavour, in turn, seeded the creation of a global immunization program. Currently, the delivery of quality immunization services helps to prevent three million deaths annually worldwide, and it is heralded as one of the most cost effective public health interventions available (3). The initial benefits of vaccination accrued to countries that could afford to implement child immunization programs. In fact, when the World Health Organization (WHO) first initiated its Expanded Program on Immunization (EPI) in the mid-1970s, global vaccination coverage was an abysmal 5% for the six basic EPI vaccines: bacillus Calmette-Guréin, oral poliovirus, diphtheria, tetanus, pertussis and measles (2). It was only through the concerted efforts of the United Nations Children's Fund, WHO and private foundations, such as Rotary International, that the international community became increasingly aware of the importance of the Universal Child Immunization program. Appropriate financial resources were then allocated, resulting in a peak vaccination coverage of 81% by 1990 (Figure 1) (4). Global coverage of diphtheria-tetanus-pertussis from 1980 to 1998. Reproduced from reference 4 Unfortunately, faced with economic setbacks, competing national priorities and diminishing international interest, vaccination coverage stagnated and, even, dropped in a number of countries towards the turn of the millennium (5). The global coverage for diphtheria-tetanus-pertussis is now estimated to be 74% (6); this figure may be an overestimate of the real situation (7). The final result is that, worldwide, an estimated three million deaths still occur annually from vaccine-preventable diseases, despite a new schedule, including vaccinations for hepatitis B, Haemophilus influenzae type b (Hib) and yellow fever, used in those countries where it is warranted on public health grounds (7). One child in four is still not fully immunized against major childhood killers such as diphtheria, whooping cough, tetanus, polio, measles and tuberculosis by his or her first birthday (8). This is true despite the inexpensive cost of a full immunization package against the six basic EPI antigens, which is estimated to be US$17 per child (6). Infectious diseases contribute to more than two-thirds of the estimated 11 million to 12 million deaths annually of children younger than five years of age (9). More than half of these deaths are due to acute respiratory infections, diarrhoeal diseases, measles and other vaccine-preventable diseases. New vaccines have been introduced or may soon be available to fight a number of these pathogens, such as: Hib: To date, thousands of babies in richer countries have benefited from the dramatic reduction in Hib-related diseases. However, worldwide, an estimated 400,000 deaths still occur from Hib (10). Streptococcus pneumoniae: The newer childhhod seven-valent pneumococcal conjugate vaccine against S pneumoniae was approved by the US Federal Drug Administration on February 17, 2000; S pneumoniae is a major contributor to acute respiratory diseases, meningitis and septicaemia. A similar vaccine, which is formulated specifically for developing countries at a cost that is affordable to governments, may not be available for several years. Meanwhile, three million children in developing nations continue to die annually from non-Hib-related acute respiratory infections (10). Rotavirus: The American tetravalent rotavirus vaccine, which was licensed in 1998, was withdrawn recently because of an increased rate of intussusception in vaccinees (2). Given that the risk of morbidity and mortality from rotavirus-related diarrhoeal disease that is experienced by children in developing countries far exceeds the risk of developing intussusception from the vaccine, the ethical issue of withholding this potentially life-saving intervention from developing countries needs to be debated further. Newer vaccines, along with others such as yellow fever and hepatitis B, hold great promise against infectious disease threats. But, much work needs to be done to introduce these vaccines into existing national immunization schedules. It is also necessary to concentrate on boosting the faltering coverage rates of the six basic EPI vaccines. There are nearly one million measles-related deaths/year, despite the existence of a cheap, highly efficacious vaccine (11). The research and development of new vaccines focuses on diseases with a limited global burden and that are relevant to industrialized nations only. In fact, of the US$56 billion devoted annually to health research, less than 10% is directed towards diseases that afflict 90% of the world's population (12). With specific reference to vaccine research, Seth Berkely, president of the International AIDS Vaccine Initiative, notes that about US$2 billion dollars are spent annually on medical research into costly treatments, which are well beyond the reach of the majority of individuals with the human immunodeficiency virus (HIV) (12). Only $250 million is actually spent on the development of a vaccine that could prevent the devastating consequences of HIV infection (12). Furthermore, in the 1999 Report of the United States Institute of Medicine Report, Vaccines for the 21st Century: Tools for Decision Making (13), priorities for vaccine development are listed for 26 diseases, ranking cytomegalovirus, influenza, group B streptococcus and S pneumoniae as having the highest priority. Mycobacterium tuberculosis, although included, received a lower rating. There was no mention of vaccine research and development for diseases such as HIV/AIDS and malaria, which after acute respiratory infections, diarrhoeal diseases and measles, are the next great infectious killers of children younger than five years of age (12). This priority ranking should be expected to change after the announcement by US President Bill Clinton in his State of the Union address on January 27, 2000. He proposed to provide a US$1 billion credit, dollar for dollar, for the sale of vaccines against malaria, HIV/AIDS and tuberculosis as an innovative way to stimulate such markets (14). In addition, in the Vaccines for the New Millennium Act introduced on March 1, 2000, the United States proposes to authorize US$30 million during 2001/02 to the International AIDS Vaccine Initiative to speed the development and distribution of preventive AIDS vaccines by providing venture capital for industry research and development efforts. Canada is deeply aware of global inequities in basic immunization coverage and access to newly developed vaccines. Canada has made a firm commitment to improve the health of children through the full immunization of every child, and in particular, to eradicate polio and measles. This objective is reflected in the Strategy for Health developed in 1996. In addition, Canada has had a long history of focusing its international efforts on improving immunization programs. From 1986 to 1996, through CIDA, Canada provided on average $14 million/year towards immunization efforts through various programs, including the Canadian International Immunization Programme and the Global Polio Eradication Program. However, until recently, annual disbursements for projects that are purely related to immunization had, in fact, dropped progressively from 1994/95 to 1997/98 ($12.7 million to $9.8 million and $6.5 million to $5.7 million, respectively). It is difficult to compare Canada's overall performance on an international scale because exact global estimates for immunization support are hard to obtain due to a variable mix of targeted, integrated, pooled and untied funding by donors. At a minimum, several hundred million American dollars are used to support immunization programs each year, with funding slipping in the mid- to late-1990s. Concerned about the insufficient attention that global immunization programs were receiving in this period, CIDA launched the Canadian International Immunization Initiative (CIII) in 1998 (see Table 1). The Canadian International Immunization Initiative CIDA provides the Canadian Public Health Association (CPHA) with a contribution of $500,000 per year for five years. CPHA has been tasked with the responsibility of recruiting appropriate Canadian health professionals for immunization-related activities in developing countries with 80% of this grant and with partnering with other Canadian institutions in a domestic public awareness and outreach program with the remainder of the funding. Canadian health professionals interested in going overseas on short term assignments should contact Mr Ian Stein, the CPHA coordinator of this technical support component at < ciii@cpha.ca > (17). To date, Canada has sent its Chief of Immunization to the World Health Organization (WHO) to strengthen the global immunization effort, as well as a number of other Canadians on both long and short term postings. CIDA also funds the strengthening of smaller scale immunization programs through a number of Canadian nongovernmental organizations mainly in countries where the need is greatest such as sub-Saharan Africa and south Asia. Again, this is with a contribution of $500,000 per year for five years. CIDA provides the United Nations Children's Fund with an annual grant of $4.25 million for five years to strengthen national immunization programs, and procure Canadian vaccines, auto-disable syringes, safety boxes and other immunization supplies at internationally competitive prices. In fact, in 1998, CIDA provided the United Nations Children's Fund with enough Canadian vaccines to immunize more than 10 million children against measles. CIDA continues to be a major supporter of WHO. Through CIII, CIDA provides WHO with an annual grant of $4.25 million over five years to strengthen national immunization programs by addressing technical and programmatic aspects, management, information and surveillance systems. Finally, the Pan American Health Organization receives $500,000 per annum to support ongoing work in the area of epidemiological surveillance and the introduction of additional priority vaccines. CIDA provides the Canadian Public Health Association (CPHA) with a contribution of $500,000 per year for five years. CPHA has been tasked with the responsibility of recruiting appropriate Canadian health professionals for immunization-related activities in developing countries with 80% of this grant and with partnering with other Canadian institutions in a domestic public awareness and outreach program with the remainder of the funding. Canadian health professionals interested in going overseas on short term assignments should contact Mr Ian Stein, the CPHA coordinator of this technical support component at < ciii@cpha.ca > (17). To date, Canada has sent its Chief of Immunization to the World Health Organization (WHO) to strengthen the global immunization effort, as well as a number of other Canadians on both long and short term postings. CIDA also funds the strengthening of smaller scale immunization programs through a number of Canadian nongovernmental organizations mainly in countries where the need is greatest such as sub-Saharan Africa and south Asia. Again, this is with a contribution of $500,000 per year for five years. CIDA provides the United Nations Children's Fund with an annual grant of $4.25 million for five years to strengthen national immunization programs, and procure Canadian vaccines, auto-disable syringes, safety boxes and other immunization supplies at internationally competitive prices. In fact, in 1998, CIDA provided the United Nations Children's Fund with enough Canadian vaccines to immunize more than 10 million children against measles. CIDA continues to be a major supporter of WHO. Through CIII, CIDA provides WHO with an annual grant of $4.25 million over five years to strengthen national immunization programs by addressing technical and programmatic aspects, management, information and surveillance systems. Finally, the Pan American Health Organization receives $500,000 per annum to support ongoing work in the area of epidemiological surveillance and the introduction of additional priority vaccines. The Canadian International Immunization Initiative CIDA provides the Canadian Public Health Association (CPHA) with a contribution of $500,000 per year for five years. CPHA has been tasked with the responsibility of recruiting appropriate Canadian health professionals for immunization-related activities in developing countries with 80% of this grant and with partnering with other Canadian institutions in a domestic public awareness and outreach program with the remainder of the funding. Canadian health professionals interested in going overseas on short term assignments should contact Mr Ian Stein, the CPHA coordinator of this technical support component at < ciii@cpha.ca > (17). To date, Canada has sent its Chief of Immunization to the World Health Organization (WHO) to strengthen the global immunization effort, as well as a number of other Canadians on both long and short term postings. CIDA also funds the strengthening of smaller scale immunization programs through a number of Canadian nongovernmental organizations mainly in countries where the need is greatest such as sub-Saharan Africa and south Asia. Again, this is with a contribution of $500,000 per year for five years. CIDA provides the United Nations Children's Fund with an annual grant of $4.25 million for five years to strengthen national immunization programs, and procure Canadian vaccines, auto-disable syringes, safety boxes and other immunization supplies at internationally competitive prices. In fact, in 1998, CIDA provided the United Nations Children's Fund with enough Canadian vaccines to immunize more than 10 million children against measles. CIDA continues to be a major supporter of WHO. Through CIII, CIDA provides WHO with an annual grant of $4.25 million over five years to strengthen national immunization programs by addressing technical and programmatic aspects, management, information and surveillance systems. Finally, the Pan American Health Organization receives $500,000 per annum to support ongoing work in the area of epidemiological surveillance and the introduction of additional priority vaccines. CIDA provides the Canadian Public Health Association (CPHA) with a contribution of $500,000 per year for five years. CPHA has been tasked with the responsibility of recruiting appropriate Canadian health professionals for immunization-related activities in developing countries with 80% of this grant and with partnering with other Canadian institutions in a domestic public awareness and outreach program with the remainder of the funding. Canadian health professionals interested in going overseas on short term assignments should contact Mr Ian Stein, the CPHA coordinator of this technical support component at < ciii@cpha.ca > (17). To date, Canada has sent its Chief of Immunization to the World Health Organization (WHO) to strengthen the global immunization effort, as well as a number of other Canadians on both long and short term postings. CIDA also funds the strengthening of smaller scale immunization programs through a number of Canadian nongovernmental organizations mainly in countries where the need is greatest such as sub-Saharan Africa and south Asia. Again, this is with a contribution of $500,000 per year for five years. CIDA provides the United Nations Children's Fund with an annual grant of $4.25 million for five years to strengthen national immunization programs, and procure Canadian vaccines, auto-disable syringes, safety boxes and other immunization supplies at internationally competitive prices. In fact, in 1998, CIDA provided the United Nations Children's Fund with enough Canadian vaccines to immunize more than 10 million children against measles. CIDA continues to be a major supporter of WHO. Through CIII, CIDA provides WHO with an annual grant of $4.25 million over five years to strengthen national immunization programs by addressing technical and programmatic aspects, management, information and surveillance systems. Finally, the Pan American Health Organization receives $500,000 per annum to support ongoing work in the area of epidemiological surveillance and the introduction of additional priority vaccines. Through initiatives such as CIII, Canada is one of several major international players that has helped to reinvigorate international focus on the importance of immunization. CIDA played a key role in the recent development of the Global Alliance for Vaccines and Immunization (GAVI), which was officially launched in Davos, Switzerland at the World Economic Forum on January 31, 2000. GAVI represents a global partnership of WHO, the United Nations Children's Fund, the World Bank, the Bill and Melinda Gates Foundation, the Rockefeller Foundation, national governments of both developing countries and donor countries, industry and the research community (6). Through its renewed international commitment, it is hoped that GAVI will build on the success of the polio eradication campaign to ensure the following: By 2005, 80% of developing countries will have routine immunization coverage of at least 80% in all districts. By 2002, 80% of countries with adequate delivery systems will introduce hepatitis B vaccine, and all countries will introduce this vaccine by 2007. By 2005, 50% of the poorest countries with a high burden of disease and adequate delivery systems will have introduced Hib vaccine (6). Promising new vaccines in the near future include the new pneumococcal conjugate with an appropriate formulation for developing country serotypes and a revised formulation for the rotavirus vaccine. Through its research and development components, GAVI will contribute to an enhanced effort towards the development of vaccines against HIV/AIDS, malaria and tuberculosis. To date, GAVI has already received new funding of US$750 million over five years from the Bill and Melinda Gates Foundation. An additional US$150 million has been pledged by the United States over the next two fiscal years. This renewed partnership should have a major impact on immunizing every child and reaching the unreached, especially the poor. An update on the progress of this international coalition will be presented at the Fourth Canadian National Immunization Conference in December 2000 (15).

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