WHO to consider 2020 global measles eradication goal

Progress toward elimination in the various WHO regions has been steady since 2000. Now studies are under way to evaluate feasibility of a global goal.

During the next year, WHO officials may take a major step toward worldwide measles eradication. With five of the six WHO regions having already declared eradication goals, the organization is considering the feasibility of a worldwide eradication goal by 2020. However, all countries face financial and political barriers toward achieving these goals.

“Certainly, global measles eradication is biologically feasible; it’s a virus on the short list of candidates for eradication because it fulfills certain criteria, including that there’s no nonhuman host,” said Stephen L. Cochi, MD, MPH, senior adviser, Global Immunization Division, National Center for Immunization and Respiratory Diseases at the CDC in Atlanta.

“There’s an effective tool to stop the disease, namely measles vaccine, which is highly effective and inexpensive for the developing world through UNICEF procurement,” Cochi told Infectious Diseases in Children. “And there’s been a demonstration in a large geographic area already of the feasibility of measles eradication, namely in the entire Western Hemisphere, where we’re now approaching 8 years with sustained interruption of the endemic measles virus.”

In May 2009, the executive board of WHO initiated a process to assess the feasibility of proceeding with a global measles eradication target, according to Cochi. The assessment includes examining political and financial issues, biologic feasibility, cost- effectiveness and programmatic feasibility. Each WHO region was asked to conduct a review of their respective countries last summer and fall. “Those reports were very positive in terms of the view that there was pretty good positioning for proceeding if there were sufficient resources and a target declared,” Cochi said.

He expects the WHO executive board and World Health Assembly will decide whether to set a 2020 target during 2011 or 2012. The feasibility reports will first be made available to the WHO executive board during its biannual meeting in January, during which time they will discuss whether to set the target, request further information or discuss the issue at the World Health Assembly meeting in May, Cochi said.

Progress in mortality reduction

One of the current global WHO goals is to reduce measles mortality by 90% by 2010. Remarkable progress has occurred as a result of 46 of 47 low-income priority countries (except India) implementing the proven strategies for eliminating measles. Although mortality has dropped 78% since 2000 — a reduction from an estimated 733,000 deaths in 2000 to 164,000 in 2008 — achievement of this goal by the end of 2010 does not seem likely. All WHO regions, except for Southeast Asia, have achieved the 90% reduction goal, according to a January WHO executive board summary. Within the Southeast Asia region, India is the only country that has not achieved this goal and accounts for most of the remaining global measles mortality burden.

“Approximately three-fourths of those remaining deaths are in India, so we can’t reach the 2010 target until and unless India fully engages and implements the proven strategies that the other 46 high-risk, poorer countries have implemented to get us where we are now,” Cochi said.

In 2000, those 47 countries carried 95% of the measles mortality burden, according to Edward Hoekstra, MD, MSc, senior health specialist with the Global Measles Program and Health Emergencies at UNICEF in New York. Children in each of these countries were receiving one dose of measles vaccine, rather than two.

UNICEF and the other Measles Initiative partner organizations worked with the governments in these 47 countries — except for India — to launch measles vaccine campaigns. All children aged 1 to 14 years were given a dose of measles vaccine during this “catch-up” campaign regardless of their prior vaccination status, and then follow-up campaigns were conducted every 3 to 4 years to vaccinate children since the previous mass campaign. Hoekstra said China is planning a nationwide follow-up campaign later this year, in which they will vaccinate more than 100 million children in 3 weeks.

According to Hoekstra, India has set a 90% mortality reduction goal by 2013. He also said that the government has recently decided to start introducing a second routine dose of the measles vaccine in that country. In 21 of the 35 states, immunization coverage is more than 80%, and each of these states will implement a second dose this year. The remaining 14 states will hold a campaign to vaccinate all children up to age 10 years, rather than 15 years, because most children in India will have had measles by age 10 years.

“We will be close to reaching our 90% [mortality reduction] goal globally at the end of the year, but I think in 2011 and at the latest 2012, we will reach the goal, depending on how many kids they can and will vaccinate in [India],” Hoekstra said.

Progress in each WHO region

In 1994, the WHO region of the Americas established a measles elimination goal for 2000 and met that goal in 2002. The entire Western Hemisphere is still in a state of sustained interruption of measles, and the only cases seen in the Americas are those imported from other parts of the world, Cochi said.

The European region and the Eastern Mediterranean region have set 2010 as the eradication target date and the Western Pacific region has set 2012. “All three of these regions have made a lot of progress in terms of both reducing measles cases and measles deaths … but certainly the European region and the Eastern Mediterranean region are very likely to miss the 2010 target,” Cochi said.

These three regions are now establishing a process for creating national commissions and a regional commission, both made up of independent experts, to review the situation and institute a closer and monitoring process going forward.

In the European region, measles incidence declined from 110 cases per million population to less than 10 cases per million in 2007-2008. However, in 2008, Western European countries saw a resurgence of measles cases, with the majority of outbreaks in unimmunized populations of countries where immunization programs are being challenged.

In 2009, 7,173 measles cases were reported from 32 countries in the European region, according to a EUVAC.NET Measles Surveillance Annual Report. Bulgaria is also in the midst of a measles outbreak, which was first reported in April 2009, according to Mark Muscat, MD, scientific coordinator in the department of epidemiology at Sans Serum Institute in Copenhagen, Denmark. Muscat said Bulgaria has now reported almost 18,000 cases and 20 deaths.

“This is a very sad situation. In a year when we were hoping measles could be eliminated from Europe, we are still seeing large populations in certain countries that are not vaccinated against measles,” Muscat said

Certain populations in Europe, including the Roma people in Bulgaria and the anthroposophic communities in German-speaking countries, are not vaccinated because of cultural beliefs and lack of access to health care.

The Wakefield study, which claimed to have found a link between autism and vaccines and has since been retracted, had a particular negative effect in Europe, specifically in the United Kingdom. “Following that article, there was a drop in the number of people vaccinated in the United Kingdom because both parents and the medical profession were confused as to what to do,” Muscat said.

Muscat is optimistic that the goal of eradication in Europe can be met in the next 5 to 10 years.

First-dose measles vaccine coverage increased from 69% in 1997 to 83% in 2008 in the Eastern Mediterranean region. However, according to the WHO executive board summary, this region faces challenges to elimination: No funding sources have been identified for measles follow-up supplementary immunization in 2010 and after for 12 countries. In addition, shortages of human resources have hindered surveillance, and in four of the countries in this region, vaccination coverage rates are at a standstill because of weak health systems.

In the Western Pacific region, first-dose measles vaccination coverage increased to 91% by 2008. With China’s recent campaign to conduct supplementary immunization activities and an increase in two-dose measles coverage in Japan, the region might attain its goal of elimination by 2012. However, if not successful, the region will likely achieve elimination by 2015, according to the WHO executive board summary.

The African region achieved its goal of 90% measles mortality reduction in 2006. In 2009, the region then set a target of elimination by 2020. According to the WHO summary, a collective effort between member states and the Measles Initiative in this region led to an improvement in first-dose measles vaccination coverage from 52% to 74%. “The African region has just done a superb job,” Cochi said. “It had the highest measles death burden of all the regions back in 2000.”

Southeast Asia is the only region without a target for measles elimination. Routine immunization in this region has improved, from 61% in 2000 to 75% in 2008, and the reported measles incidence has declined from 80 to 47 cases per million population, according to the WHO executive summary. “Ten out of 11 countries in that region, excepting India, have already indicated that they want to go for regional elimination,” Cochi said. “India has been reluctant to set a target date. There’s been discussion about 2020 for that region as well.”

India’s reluctance to set a target can be attributed to competing health priority demands in the country, namely polio eradication. However, there have been indications that India will start concentrating on measles as well.

Risk for resurgence

In a 2004 article in Pediatrics, H. Cody Meissner, MD, chief of pediatric infectious disease at Tufts Medical Center in Boston, and colleagues discussed a possibility of measles resurgence due to a reduction in political and financial commitment toward measles control.

In 2008, this possibility was brought closer to reality when 140 cases of measles were reported in the United States — double the number from the preceding years, according to Meissner. Most cases were imported into the United States, and unimmunized individuals were affected.

Meissner said it is important that people do not relax the requirements for vaccination; even though it is rare to see a case of measles in the United States, measles remains a continuing threat due to importations.

“It’s so important for people to understand that the measles vaccine has been licensed in the United States since 1963 — so almost 50 years,” Meissner said. “And you ask yourself, when we’ve got such an inexpensive and safe and effective vaccine, after almost 50 years of availability, why do we continue to have concerns about this vaccine?”

Cochi expressed concern that the Measles Initiative is becoming a victim of its own success because complacency has set in and financial commitment is lacking. In fact, he said that global funding from international organizations and agencies has dropped from about $150 million in 2007 to about $50 million in 2009 — 2010 is not looking any better.

The WHO executive board summary also noted that its Strategic Advisory Group of Experts on immunization had expressed concern about the decline in funding for measles control since 2008. The advisory group concluded that a resurgence of measles will occur if adequate resources are not guaranteed.

“What we think of measles and what Africa thinks of measles are two totally different ideas,” Hoekstra said. “That’s sometimes been a bit of a problem with our donors because they often don’t understand why measles is such a big issue.”

On the other hand, industrialized nations are seeing firsthand the negative effects of complacency, most specifically in Europe. “They had stopped measles transmission in Great Britain and now it’s back and has reestablished itself because of unfounded fears about the safety of the vaccine and the anti-vaccine movement,” Cochi said. “Anti-vaccine blogs and websites have proliferated now from the industrialized world to Eastern Europe, former Soviet Union countries and into some of the developing countries.”

Feasibility of the 2020 goal

The International Task Force for Disease Eradication completed a review in 2009 and concluded that measles eradication is biologically feasible. Programmatic feasibility has been demonstrated by the Americas region’s sustained elimination. The WHO executive board is awaiting study data on other requirements for setting a global eradication goal, including sufficient vaccine supply, cost-effectiveness, availability of resources, contribution to the health system, compatibility with other child health programs, and sufficient political and financial commitment.

The main obstacle is operationalizing the political commitment and biological feasibility to a high level of social commitment on all levels. Cochi is optimistic that the goal will be set within the next 1 to 2 years “There has been good progress so far this year toward polio eradication,” he said. “Continued progress toward polio eradication … will certainly ease up on any pressure that might act against considering establishing another global eradication initiative.”

In a 2008 article, Ciro de Quadros, MD, executive vice president at the Sabin Institute, and colleagues concluded that global elimination of measles is feasible — but only if countries fully apply the appropriate strategies of vaccination and recommended surveillance of measles, as recommended by the Pan-American Health Organization for the Americas region.

De Quadros told Infectious Diseases in Children that all resources must be identified and secured before a goal is set. “If not, you go into the same problems that polio eradication has gone through, which is a funding gap,” de Quadros said. “That’s what needs to be done now: [creating] a comprehensive plan, identifying the strategies correctly, and identifying and securing the resources before you launch a global initiative.”

In Europe, Muscat called for consolidating the strategies established for the WHO European region elimination target. He also said they need to concentrate on maintaining high vaccination coverage with a focus on certain groups, including the Roma and anthroposophic communities.

“We should continue advocating for use of the vaccine because that is a fundamental strategy to eliminating measles and hopefully eradicating it globally at one point,” Muscat said. “Apart from the strategy of vaccinating, we should continue as public health officials to monitor and survey … the progress of [measles] elimination.”

Meissner added that it is important that “unscientific and unsound theories” about autism or other neurologic disorders be disproven. “Education is important for parents so that they understand that these are completely unfounded theories,” he said.

“If all continents and all regions of the world work together and do the utmost in their own respective regions, then hopefully we might even eradicate measles in our lifetime,” Muscat said. – by Tina DiMarcantonio

Is a global measles elimination target feasible, and what else needs to be done to achieve that goal?

For more information:

• de Quadros CA, Andrus JK, Danovaro-Holliday MC, et al. Feasibility of global measles eradication after interruption of transmission in the Americas. Expert Rev. Vaccines. 2008;7(3):355-382.
• EUVAC.NET. Measles Surveillance Annual Report, 2009. http://www.euvac.net/graphics/euvac/pdf/annual_2009.pdf
• Meissner HC, Strebel PM, Orenstein WA. Measles vaccines and the potential for worldwide eradication of measles. Pediatrics. 2004;114:1065-1069.
• WHO Executive Board. Global Eradication of Measles: Report by the Secretariat. January 2010.