Impact of the SARS-CoV-2 pandemic on vaccine-preventable disease campaigns

Abstract

Background: The COVID-19 pandemic has contributed to the widespread disruption of immunization services, including the postponement of mass vaccination campaigns.

Methods: In May 2020, the World Health Organization and partners started monitoring COVID-19-related disruptions to mass vaccination campaigns against cholera, measles, meningitis A, polio, tetanus-diphtheria, typhoid, and yellow fever through the Immunization Repository Campaign Delay Tracker. The authors reviewed the number and target population of reported preventive and outbreak response vaccination campaigns scheduled, postponed, canceled, and reinstated at 4 time points: May 2020, December 2020, May 2021, and December 2021.

Findings: Mass vaccination campaigns across all vaccines were disrupted heavily by COVID-19. In May 2020, 105 of 183 (57%) campaigns were postponed or canceled in 57 countries because of COVID-19, with an estimated 796 million postponed or missed vaccine doses. Campaign resumption was observed beginning in July 2020. In December 2021, 77 of 472 (16%) campaigns in 54 countries, mainly in the African Region, were still postponed or canceled because of COVID-19, with about 382 million postponed or missed vaccine doses.

Interpretation: There is likely a high risk of vaccine-preventable disease outbreaks across all regions because of an increased number of susceptible persons resulting from the large-scale mass vaccination campaign postponement caused by COVID-19.

Keywords: COVID; SARS-CoV-2 pandemic; campaign; global; vaccination; vaccine-preventable diseases.

Figure 1a

Number of campaigns postponed because of COVID-19 and campaigns reinstated ^a after postponement because of COVID-19, as of December 15, 2020 ^a The cumulative number of campaigns reinstated after an initial postponement caused by COVID-19. ^b 90% (19/21) monovalent oral poliovirus type2 (mOPV2), 38% (3/8) bivalent oral poliovirus types 1&3 (bOPV) and 25% (3/12) inactivated polio vaccine (IPV) campaigns were reinstated after postponement because of COVID-19. ^c This column includes those campaigns that had ever been postponed at any point between March and December 2020 and represent the cumulative number of reinstated campaigns plus the number of campaigns that were still being postponed/ projected to be postponed because of COVID-19 as of December 2020.

Figure 1b

Number of campaigns postponed because of COVID-19 and campaigns reinstated ^a after postponement because of COVID-19, as of May 15, 2021 ^a The cumulative number of campaigns reinstated after an initial postponement caused by COVID-19. ^b 100% (22/22) monovalent oral poliovirus type2 (mOPV2), 43% (3/7) bivalent oral poliovirus types 1&3 (bOPV) and 28% (5/18) inactivated polio vaccine (IPV) campaigns were reinstated after postponement because of COVID-19. No trivalent oral polio vaccine (tOPV) or novel oral polio vaccine type 2 (nOPV2) campaign was recorded as “postponed COVID” or “reinstated COVID”. ^c This column includes those campaigns that had ever been postponed at any point between March 2020 and May 2021 and represent the cumulative number of reinstated campaigns plus the number of campaigns that were still being postponed/ projected to be postponed because of COVID-19 as of May 2021.

Figure 1c

Number of campaigns postponed because of COVID-19 and campaigns reinstated ^a after postponement because of COVID-19, as of December 1, 2021 ^a The cumulative number of campaigns reinstated after an initial postponement caused by COVID-19. ^b 100% (22/22) monovalent oral poliovirus type2 (mOPV2), 50% (3/6) bivalent oral poliovirus types 1&3 (bOPV) and 28% (5/18) inactivated polio vaccine (IPV) campaigns were reinstated after postponement because of COVID-19. No trivalent oral polio vaccine (tOPV) or novel oral polio vaccine type 2 (nOPV2) campaign was recorded as “postponed COVID” or “reinstated COVID”. ^c This column includes those campaigns that had ever been postponed at any point between March 2020 and December 2021 and represent the cumulative number of reinstated campaigns plus the number of campaigns that were still being postponed/ projected to be postponed because of COVID-19 as of December 2021.

Figure 2

COVID-19 related campaign postponement and resumption, by vaccine *, May 2020 to December 2021 (a) Vaccination campaigns postponed because of COVID-19. Note: This figure depicts the total number of campaigns that had previously been planned to take place, but that were projected to be postponed because of COVID-19. Campaigns that had been reinstated, even if implementation was delayed from the originally planned date, were removed from the postponement tally. This graph does not include the number of campaigns that were postponed because of non-COVID related reasons or the number of canceled campaigns. No trivalent oral polio vaccine (tOPV) or novel oral polio vaccine type 2 (nOPV2) campaign was recorded as “postponed COVID”. * Measles containing vaccines (MCV) including measles, measles rubella (MR), and measles mumps rubella (MMR); polio vaccines including bivalent oral polio vaccine types 1 and 3 (bOPV), monovalent oral polio vaccine type 2 (mOPV2) and inactivated polio vaccine (IPV); meningitis A conjugate vaccine (MenA); tetanus-diphtheria vaccine (Td); yellow fever vaccine (YF); typhoid conjugate vaccine (TCV); and oral cholera vaccine (OCV). (b) Progress on campaign resumption (campaigns that were previously postponed by COVID-19) Note: This figure depicts the total number of campaigns that had previously been postponed because of COVID-19 but have restarted. The date refers to when the campaign was conducted. This graph does not include the number of campaigns reinstated after an initial postponement because of non-COVID-related reasons. No trivalent oral polio vaccine (tOPV) or novel oral polio vaccine type 2 (nOPV2) campaign was recorded as “postponed COVID” or “reinstated COVID”. * Measles containing vaccines (MCV) including measles, measles rubella (MR), and measles mumps rubella (MMR); polio vaccines including bivalent oral polio vaccine types 1 and 3 (bOPV), monovalent oral polio vaccine type 2 (mOPV2) and inactivated polio vaccine (IPV); meningitis A conjugate vaccine (MenA); tetanus-diphtheria vaccine (Td); yellow fever vaccine (YF); typhoid conjugate vaccine (TCV); and oral cholera vaccine (OCV).

Figure 3

a: Vaccination campaign status, by country, as of May 15, 2020 b: Vaccination campaign status, by country, as of December 15, 2020 c: Vaccination campaign status, by country, as of May 15, 2021 d: Vaccination campaign status, by country, as of December 1, 2021