Varied impact of COVID-19 on routine immunization in the European Region

The WHO European Region saw a 1% decrease in routine immunization coverage, from 95% in 2019 to 94% in 2020 (the third dose of diphtheria-tetanus-pertussis-containing vaccine (DTP3) is used as a tracer indicator), according to WHO/United Nations Children’s Fund (UNICEF) estimates for routine coverage in 2020, released on 15 July 2021.

The Region as a whole continues to achieve high routine immunization coverage, and experienced a smaller decline during 2020 than all other regions of the world. The figures for 2020 are preliminary, based on data reported through the annual WHO/UNICEF Joint Reporting Form by only 36 (68%) of the Member States in the Region. The figures will be revised later in 2021 as more complete data become available.

The relatively small decrease in regional DTP3 coverage reflects intense efforts made by the ministries of health in the Region to continue or catch up on childhood immunizations, despite programmatic restrictions due to response measures for the COVID-19 pandemic.

However, the decrease masks large variations among countries, larger declines in some countries, and a lack of reported data from some countries where COVID-19 disruptions have also affected capacity to collect and report routine immunization coverage data.

Among the 36 European Member States for which estimates are available, a significant (≥ 5%) general drop in routine immunization coverage (across all antigens combined) was reported by Azerbaijan, Bulgaria, Georgia, Kazakhstan, Kyrgyzstan and the Republic of Moldova.

Lesser declines, with values below the regional target of 95% coverage, were reported by Italy (all antigens) and by Denmark, Lithuania and Romania (measles- and rubella-containing vaccines).

A few countries reported a slight increase in coverage for DTP3 and the first dose of measles-containing vaccine (MCV1), with more notable increases reported by Estonia and San Marino. Ukraine reported a decrease in MCV1 coverage but also an increase in DTP1 and DTP3.

Montenegro reported worryingly low coverage for measles, which fell to 24% in 2020 from an already low 33% in 2019. Other countries reported coverage levels comparable to 2019.

Accumulation of unvaccinated children can reverse decline in measles cases

Attaining the optimal immunization coverage (≥ 95%) with 2 measles- and rubella-containing vaccine doses at all subnational levels (provinces, regions and districts) while closing immunity gaps in all age groups is crucial for the elimination of measles and rubella.

While reported measles cases have declined dramatically (from over 104 000 in 2019 to approximately 12 000 in 2020, and only 59 for January to May this year so far), any decrease in vaccination coverage can lead to a rapid accumulation of vulnerable children and potentially fuel large outbreaks in the future.

Moreover, it is likely that factors related to the implementation of national COVID-19 response measures during 2020 contributed to the observed decline in reported measles cases in the Region. These include:

• fewer visits to hospitals and medical practitioners during full or partial lockdowns, which may have led to milder cases of disease going undetected;
• decreased measles and rubella virus transmission as a result of non-pharmaceutical measures such as stay-at-home recommendations, school closures, bans on mass gatherings, international border closures, widespread physical distancing, and improved hand hygiene and coughing/sneezing etiquette; and
• interrupted or disrupted disease surveillance due to the diversion of human and other resources to the COVID-19 response.

Measles continues to be endemic in many countries around the world and will resurge wherever it finds sufficient vulnerable people to infect. It is vital for children’s health that any missed vaccinations, against measles or any other vaccine-preventable disease, be caught up as quickly as possible.

Addressing COVID-19 challenges at the country level

The relatively small changes in coverage reported by many countries in the Region in 2020 are a reflection of the commitment and substantial efforts of national health system to ensure – and assure parents and caregivers – that routine vaccination sessions could continue with appropriate infection prevention control measures at the vaccination points for both parents and health workers.

In the Netherlands, for example, based on preliminary published data, vaccination coverage remained relatively high for nearly all vaccines in 2020, despite a temporary dip in monthly coverage in March 2020. Several initiatives implemented together prevented a major disruption to immunization service delivery in 2020:

• Group/mass vaccination events were converted into personal appointments with parents and children.
• Missed vaccinations were rescheduled in combination with other vaccinations (for example, human papillomavirus with meningitis ACWY).
• All mother-and-child care offices were kept open, with only 1 parent and child allowed to visit at a time.
• Invitations for vaccination included a flyer informing people on the safety of routine vaccination during the COVID-19 pandemic.
• The safety of immunization during the pandemic was also highlighted by the media.

European Immunization Agenda 2030

To tackle the challenges of the next decade, including the impact of COVID-19 on immunization systems and coverage, the Region will initiate a new immunization strategy to be presented to the WHO Regional Committee for Europe in September 2021. The European Immunization Agenda 2030 is a country-led policy framework focused on strengthening immunization systems in order to reduce the burden of vaccine-preventable diseases among all people at all ages.

Global picture

Globally, 23 million children missed out on lifesaving vaccines through routine vaccination services in 2020 – 3.7 million more than in 2019. This is the highest number of unvaccinated children since 2009, taking us back more than a decade. The majority of these children (up to 17 million) did not receive a single vaccine, highlighting immense inequities in vaccine access.

Without high childhood vaccination rates, countries face risks of multiple epidemics. This could be catastrophic in the context of COVID-19, particularly for countries with the weakest health systems.