UNICEF-WHO Philippines: Polio Outbreak Situation Report #8 (19 November 2019)

Report
from World Health Organization, UN Children's Fund
Published on 19 Nov 2019

Highlights

  • No new confirmed cases in the past week.

  • Preparations ongoing for next round of synchronized polio vaccination campaign on 25 November-7 December targeting 4.4 million children under 5 in National Capital Region (NCR) and 6 regions in Mindanao.

  • Second batch of 1,206,000 doses of monovalent Oral Polio Vaccine against type 2 (mOPV2) to arrive on 25 November.

  • High-profile preparatory meeting with over 60 governors, mayors and other key stakeholders for Mindanao held in Davao on 12 November.

  • Current polio outbreak resulting from persistently low routine immunization coverage, and poor sanitation and hygiene.

  • Philippines is affected by both cVDPV1 and cVDPV2. cVDPV is considered a public health emergency of international concern (PHEIC).

Current Situation

No new human cases confirmed this week.

So far, 4 human cases confirmed with polio: 3 with circulating vaccine-derived poliovirus type 2 (cVDPV2) from the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM) and 1 with immunodeficiencyrelated VDPV type 2 (iVDPV2) from Laguna; as well as 16 environmental samples: 11 for poliovirus type 1 and 5 for type 2.

In response to the 2 latest confirmed cases relatively close to one another, the Department of Health (DOH) vaccinated 16,664 children 0-59 months old in Lambayong (Sultan Kudarat province), Datu Piang, and Datu Paglas (Maguindanao province) on 4-8 November, 95% of the target.

All samples were tested by the National Polio Laboratory at the Research Institute for Tropical Medicine (RITM), whereas sequencing and genetic analysis is done at the NIID in Japan and additional genetic characterization provided by the United States Centers for Disease Control and Prevention (CDC).

The NIID and CDC confirmed that all VDPV1 samples were genetically linked but did not find a genetic linkage with any other known VDPV1 detected globally, indicating new emergence.
Comparison done at NIID and CDC in poliovirus databases showed the Laguna case not to be genetically linked with any other known type 2 poliovirus, indicating new emergence. All other VDPV2 samples are genetically linked.

After the successful round of synchronized polio vaccination campaigns on 14-27 October, where 1,628,717 children 0-59 months old were vaccinated, preparations are currently on going for the upcoming round on 25 November-7 December in NCR using bivalent OPV against poliovirus type 1 and 3 (targeting almost 1.3 million children under 5) and the 6 regions of Mindanao using monovalent OPV against poliovirus type 2 (over 3.1 million children under 5). The second batch of 1,206,000 doses of mOPV2 is estimated to arrive in the country on 25 November.

Particularly the Mindanao vaccination campaign is expected to be challenging, since it involves 6 different regions with a target population of over 3 million children under 5.