For the past year, I have been in China representing the Centers for Disease Control and Prevention (CDC) as the team lead on the World Health Organization (WHO) Expanded Program on Immunization (EPI). The work is great, and my Chinese colleagues are wonderful. Although immunization is immunization, there are many fascinating differences between the US program and the one in China.
Eradication of Vaccine-Preventable Diseases
In addition to the EPI team, WHO has a country office in China that has health-related teams, such as Health Care Reform, Environmental Health, and Noncommunicable Diseases. Our EPI team consists of 4 people: 2 Chinese physician epidemiologists, 1 Chinese administrative expert, and me. I’m the newest team member, having moved to Beijing just more than 1 year ago.
The mission of our team is to support China’s immunization efforts to accomplish the nation’s goals of controlling, eliminating, or eradicating vaccine-preventable diseases through effective, evidence-based immunization practices. To accomplish this, we work with the China Ministry of Health EPI division, the Chinese Center for Disease Control and Prevention’s National Immunization Program, the WHO Western Pacific Region EPI team and headquarters in Geneva, the US CDC, and other partners inside and outside of China.
The US CDC has supported WHO China EPI for more than 2 decades by providing immunization experts and a modest amount of funding to the WHO China office. Most of the previous work has been disease-specific: polio eradication, measles elimination, and advanced hepatitis B control.
The reason that the US CDC sends people to China has a typical “immunization” answer — for both direct and indirect benefits. The direct benefits are to children in China, of course, but the indirect benefits are global. China remaining polio-free is critically important to the Global Polio Eradication Initiative; China’s eventual elimination of measles and rubella will support the global initiative that will eradicate these diseases; and China’s reduction of chronic hepatitis B among children will reduce exportation of hepatitis B virus.
Photo courtesy of Lance E. Rodewald, MD.
China’s ‘Model for the World’
Although transmission of hepatitis B virus to newborn and young children has been markedly reduced in China, the high overall rate of chronic hepatitis B infection among adults results in ongoing horizontal transmission. Determining who is newly acquiring hepatitis B infection in China, and assessing the most cost-effective means of interrupting this transmission, is a substantial technical, programmatic surveillance, and economic challenge.
The China immunization program has had a string of impressive successes over the years. China was recently verified to have reduced the prevalence of chronic hepatitis B infection among children younger than age 5 years from more than 8% in the prevaccine era to less than 1% in 2009. Because chronic infection is the source of hepatitis B transmission and the main cause of liver cancer and cirrhosis, this success will reverberate in China — and globally — forever.
Although China was certified polio-free in 2000, an imported case from Pakistan caused an outbreak in 2011 that China had to stop. China’s outbreak response was so successful that WHO called it a model for the world. In 2011, China’s national vaccine regulatory authority was certified by WHO as being able to assure the quality of China-manufactured vaccines, paving the way for prequalification of China vaccines for the Global Alliance for Vaccines and Immunization and the United Nations Children’s Fund (UNICEF) markets. And in 2012, China was verified by WHO to have eliminated maternal and neonatal tetanus.
This is a very good time for immunization in China. The immunization leadership, scientific staff, and laboratory expertise and capacity are all excellent. An effective and efficient China immunization program is vital for the health of Chinese children.
Barriers to Immunization Success in China
The successes have been striking, but the remaining challenges faced by the China program are quite daunting. Although greatly reduced in incidence, the indigenous H1 genotype of measles still circulates in most China provinces. The national goal is to eliminate measles by 2015, an effort that will require a very strong routine immunization program. Once measles is eliminated, the China program will be faced with imported cases until measles is eradicated globally, just like the current situation in the United States.
The China Ministry of Health’s EPI provides all children in China with free vaccines that protect against 12 diseases: polio, measles, mumps, rubella, diphtheria, tetanus, pertussis, hepatitis B, hepatitis A, Japanese encephalitis, invasive meningococcal disease, and tuberculosis. There is a very good immunization delivery infrastructure for these vaccines, all of which are domestically manufactured.
However, there are several vaccines in use in the US system that are not part of China EPI: Hib, pneumococcal conjugate (PCV), rotavirus, influenza, inactivated poliovirus vaccine (IPV), and human papillomavirus (HPV) vaccines. All of these vaccines except HPV vaccine are licensed and available in China, but parents need to pay out-of-pocket for the non-EPI vaccines. Because these vaccines can be relatively expensive, financially vulnerable children have diminished access to them.
Evidence-based decisions to include a new vaccine into the program require knowledge of the preventable burden of disease and an assessment of anticipated public health and economic benefits and costs. Acquiring this information is expensive and can be quite challenging. Financing for domestic vaccine development and production is essential, since all China EPI vaccines are produced in China. China has a large birth cohort that is about 4 times the size of the US birth cohort, so these considerations can be quite enormous.
The legal framework for China’s immunization program has a pathway for the inclusion of new vaccines into the program, which China is scheduled to update; management of the non-EPI vaccines is likely to be part of that update. This may ease some of the barriers to more widespread use of these vaccines.
Oral Polio Vaccine Versus Inactivated Polio Vaccine
Although polio-free for many years, China is an all oral polio vaccination (OPV) country. Last fall, the WHO’s Strategic Advisory Group of Experts recommended that OPV-using countries introduce a dose of trivalent IPV in preparation for a global switch from trivalent OPV to bivalent OPV. IPV will be needed for immunity from type 2 polio virus, the only source of which is vaccine-associated, because the wild type 2 polio virus has been eradicated.
Adding a dose of IPV to an all-OPV schedule is a substantial task that requires a reliable source of IPV, and preparation of the program, doctors, nurses, and most important, the parents. Maintaining parental confidence in OPV while introducing IPV will be critically important because high polio coverage is vital to maintaining a wall of immunity capable of preventing imported outbreaks. Because one of the key differences between OPV and IPV is the safety profile, parents understanding of the rationale and time line for changing over to IPV will be essential.
Appreciation for United States Focus on Immunization
For the past 20 years, my medical focus has been on immunization, and I would say that there are some notable similarities between immunization in the United States and China. Both countries see the tremendous value of immunization, emphasizing its public health and economic value. Similar to China, the legal framework of the US immunization program supports evidence-based immunization recommendations, and backs the Advisory Committee on Immunization Practices (ACIP) recommendations with automatic funding for the vaccines. There is the Vaccines for Children funding in the public sector, and mandated insurance coverage in the private sector. This legal structure has helped foster the development of new life-saving vaccines, and makes them available to children in a timely manner, regardless of socioeconomic status.
Having private pediatricians and family physicians responsible for the administration of the vast majority of vaccines in the US integrates immunization into comprehensive primary care. The strong epidemiology that supports immunization in the US keeps the immunization schedule safe and effective. Living abroad has helped me appreciate the depth of investment that the United States makes in the health of children through immunization.
Daily Living Abroad
The WHO office is an English-speaking environment, and many Chinese colleagues speak English. Although I take lessons in Chinese, the language, although interesting, is very difficult for me to learn. The Chinese characters are fascinating, but there are thousands of them. I have great admiration for people who can speak both languages. We have translators for many key meetings, and my workmates help me understand meetings that don’t have formal translation.
China is a very active place, with so many things to do and see. In addition to taking language classes, my wife, Patricia, and I enjoy going on day trips around Beijing, seeing performances, taking other classes, and meeting new people.
I especially like bicycling around town. Commuting is easiest by bicycle, and it is the most fun way to travel. The built environment in Beijing is especially good for bikes as there are wide bike lanes on almost all of the streets. Beijing is very flat, so the cycling challenge is not physical. Instead, cycling is more of a mental challenge with many vehicles and pedestrians in the bike lanes, forcing one to calculate many trajectories to plan a good path through the traffic. It is especially fun to be in a city with more than a million other cyclists.
We miss family, friends, and work colleagues the most. It is great to have visitors over here so we can catch up. Our son, Tom, is in college at the University of Kansas, and our daughter, Theresa, recently graduated from the University of Georgia. With modern technology, it is relatively easy to keep in touch despite being half a world away, but it is difficult being at such a distance from our children, even though they are adults.
‘Such a Privilege’
China and Chinese culture are endlessly fascinating. My business travel takes me all over China to see immunization programs and research/evaluation projects in action. It is very nice to get to see a country by working in the country. The wide variety in food, transportation, and geography is amazing.
Every day I realize that it is such a privilege to be in China working on immunization. There is a tremendous openness to collaboration on immunization projects. I love my job, and my professional colleagues here are wonderful; they are very dedicated and hardworking, but also fun to work with.
During this assignment, I’ve realized there are myriad ways to serve abroad. Many physicians develop teaching, service, or research relations in other countries that can happen on short-term, long-term, or repeated bases. Working abroad brings people with different backgrounds together for the shared goal of improving children’s health everywhere.