Globally, measles outbreaks are on the rise. In 2019, public health professionals have seen simultaneous outbreaks that span multiple continents. Two weeks ago, the Outbreak Observatory team highlighted one of these outbreaks in the United States’ Pacific Northwest. Cases linked to the outbreak—centered in Clark County, Washington—have been reported in multiple other states. Since then, the number of confirmed cases has grown to 53 (up from 39 in our previous post), not including 4 additional cases identified just over the state’s border in Multnomah County, Oregon.

A widely held belief amongst public health professionals is that vaccine hesitancy has opened the door for the global resurgence of measles and other vaccine-preventable diseases. There is a growing concern that low vaccine coverage, in small pockets or across large geographic areas, will increase the risk of devastating outbreaks. This was the case in the Clark County measles outbreak as well as an ongoing measles outbreak in Rockland County, New York and an emerging outbreak in Texas. Outside of the United States, several countries in Europe have faced similar challenges, and there has been an increased effort in the region to address growing vaccine hesitancy. Additionally, health officials in the Philippines attributed an ongoing measles outbreak that has claimed 70 lives in the past month to vaccine “fearmongering.”

In 2018, Outbreak Observatory documented the resurgence of measles and other vaccine preventable diseases. With their growing global presence and a slew of associated political challenges, these outbreaks have consistently drawn our attention and provided windows for important operational lessons. This week, we will look at two separate measles outbreaks in Madagascar and Ukraine. Both are current examples of how low vaccination coverage can provide ideal conditions for large-scale outbreaks.

Measles in Ukraine

Last week, WHO announced that the European region reported approximately 83,000 cases of measles in 2018. This was more than 3 times the number reported in 2017, including more than 54,000 cases in Ukraine alone. The Ukraine outbreak has continued into 2019, with no signs of slowing. Ukraine has reported more than 3,000 cases in the past week alone and 8 deaths since the beginning of January.

The severity of the Ukrainian measles outbreak has been attributed to a number of factors, including an uphill battle with vaccine coverage and a geopolitical conflict that have put additional stress on the country’s health infrastructure. According to the World Bank, immunization rates for children 12-23 months fell below 50% in the Ukraine during 2016. These numbers rebounded the following year, but the country is still feeling the effects of consecutive years with low coverage. The tumultuous nature of Ukraine’s immunization rates derives partly from the impact of geopolitical conflicts on the health system and growing vaccine hesitancy among the country’s constituents.

Some researchers suggest that the recent geopolitical conflicts in Ukraine have reduced the country’s capacity to achieve high levels of vaccine coverage. In the Science article published earlier this week, the author shares that in 2016, Ukrainian  vaccination rates fell because of a late order the previous year. They proposed that this delay was partially due to a shift in government attention in response to the conflict in the eastern region of the country.  This put additional stress on the Ukrainian healthcare system and reduced their capability to achieve adequate vaccine coverage.

In addition to political challenges, a number of events shook public confidence in vaccine safety. In 2008, a story of a 17-year-old male passing away shortly after receiving a measles and rubella vaccination stirred up concerns over vaccine safety.  Health officials confirmed that the cause of death was unrelated to the vaccine, but news media had already shared the story widely, raising concern and fear among some members of the public. A recent research study has also raised concerns that social media campaigns have extended the shelf life of  vaccine safety rumors. The study focused on a Russian-based disinformation campaign targeting the United States using bots and trolls on social media. Although this research was nested in the United States, there is longstanding evidence of ongoing disinformation activities in Ukraine. The steep drop in vaccine coverage from 2008 to 2010 can not be completely attributed to increased vaccine hesitancy, but there is no denying that the phenomenon has played a prominent role.   

Ukraine has taken several notable steps to contain this outbreak. In 2017, the country established a task force with intergovernmental partners with the aim of increasing vaccination coverage in vulnerable populations. Despite this renewed effort, Ukraine still saw a sharp increase in the number of cases. Ukraine’s immunization program held a workshop early this year to identify other mechanisms to improve immunization coverage in the country. The outcomes should aid health professionals in framing the challenge at hand, and when paired with vaccination campaigns, these mechanisms could help reduce the burden of this outbreak. Ukraine’s Minister of Health stated in January that the the country plans to initiate a “special operation” in the Lviv region this February to boost vaccination coverage, to be followed by similar pushes in other regions. Hopefully, this will be the first step in reducing the hold of this serious public health threat.

Measles in Madagascar

Madagascar recorded more than 53,000 measles cases between September 3, 2018 and February 5, 2019. Similar to the outbreak in Ukraine, the outbreak has been largely attributed to low vaccination coverage. There have been cases of measles in every major town, city, and village in Madagascar. Health officials believe that vaccine coverage was below 50% when the outbreak started, a drop from the 58% coverage estimate that UNICEF and the WHO reported for 2017.

These low levels of coverage stem from a number of systematic factors. One of the major factors driving Madagascar’s measles outbreak is the instability of its healthcare system. Madagascar’s health system had several major deficiencies under the previous government, but is had made strides toward a handful of impactful public health goals. After a coup in 2009, many underlying challenges still remained, and progress toward major investments that previous leadership supported, such as the construction of a $22 million hospital, were abandoned completely. Madagascar’s healthcare system has continuously played catch-up while the country’s political framework shifted, creating opportunities for outbreaks of infectious disease. Madagascar recently elected a new president, and he will face the challenge of revitalizing their healthcare system.

Madagascar’s healthcare workforce has been overworked and underfunded, leading to a decrease in the capacity to perform routine immunization, particularly for vulnerable populations, among other challenges. Additionally, the onset of this measles outbreak coincided with the beginning of the season for other infectious diseases of concern, including plague. There is speculation that the heightened focus on these pathogens limited public health attention and resources available at the beginning of the measles outbreak. An additional element adding to the severity of Madagascar’s outbreak is widespread childhood malnutrition. There is a body of academic literature that has demonstrated the role of malnutrition in compounding the effects of infectious diseases, like measles, in children.

The underlying, systemic challenges associated with Madagascar’s healthcare system could inhibit the country from addressing this challenge alone. The Madagascar government has established working relationships with the WHO and other international partners, and it will look to strengthen its immunization efforts through these cooperative efforts. In January, the WHO organized a vaccination campaign with several other agencies to reach more than 2 million children over 13 regions across the country. The results and impact of this campaign are not yet available, but the effort is a step toward increased vaccination coverage. Aside from that immunization campaign, UNICEF and USAID will continue to support response operations as well as efforts to reinforce recommended routine vaccinations.

Lessons Learned

The outbreaks in Ukraine and Madagascar illustrate the importance of ensuring high levels of vaccination coverage globally, and the outbreaks in Ukraine and the US highlight the ongoing challenge of combating vaccine hesitancy. The outbreaks in Ukraine and Madagascar provide a modern example of the risk posed by low vaccination coverage. The sheer number of cases in these outbreaks is harrowing, and these examples could be a tool in efforts to communicate the critical role of routine vaccination and and the importance of maintaining high levels of vaccine coverage. Whatever the reason—limited healthcare infrastructure, multiple health threats stretching limited response resources, or vaccine hesitancy—low vaccination coverage remains an important challenge around the world, in all healthcare settings, and these outbreaks provide objective evidence of how it can allow vaccine-preventable diseases to re-emerge anywhere in the world.

Photo courtesy of Cynthia Goldsmith
Outbreak Observatory aims to collect information on challenges and solutions associated with outbreak response and share it broadly to allow others to learn from these experiences in order to improve global outbreak response capabilities.