UNICEF-WHO Philippines: Polio Outbreak Situation Report #6 (1 November 2019)

Report
from World Health Organization, UN Children's Fund
Published on 01 Nov 2019

Highlights

  • Third confirmed case is a four-year old female from Maguindanao, who tested positive for poliovirus type 2, found to be genetically linked to the Lanao del Sur case. There will be an outbreak immunization activity on 4-8 November. for more than 21,000 children under 5 years from 3 municipalities in the area
  • Synchronized polio vaccination campaigns on 14-27 October covered 1,628,717 children 0-59 months old: 95.5% of the target.
  • Current polio outbreak resulting from persistently low routine immunization coverage, and poor sanitation and hygiene.
  • Circulating vaccine-derived poliovirus (cVDPV) is considered a public health emergency of international concern (PHEIC).

Current Situation

A new cVDPV type 2 case has been confirmed on 24 October 2019 in Maguindanao province of the Bang-samoro Autonomous Region in Muslim Mindanao (BARMM). The date of onset of paralysis for this case is 12 September 2019. Detailed epidemiological investigation for the case is ongoing. This brings the total count to three confirmed cases in the country (two cVDPV2, and one immunodeficiency-related VDPV2 or iVDPV2).
The confirmed polio case is a four-year old female from Datu Piang in Maguindanao who had not received any dose of oral polio vaccine (OPV). On 25 October, stool samples sent to the National Institute of Infectious Diseases (NIID) in Japan tested positive for VDPV2. The polio virus isolated was genetically linked to the VDPV2 from the confirmed polio case in Lanao del Sur.
In response to the newly confirmed case, the Department of Health (DOH) will be conducting an outbreak immunization activity in Datu Piang on 4-8 November for more than 21,000 children under 5 from 3 municipalities connected to the newly confirmed cVDPV2 case.
A total of 16 environmental samples have been tested positive for poliovirus up to date: 11 for cVDPV1 and 5 for cVDPV2 (See Figure 1)
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 is not genetically linked with any other known type 2 poliovirus, indicating new emergence. All other VDPV2 samples are genetically linked.
Synchronized polio vaccination campaigns on 14-27 October covered 1,628,717 children 0-59 months: 95.5% of the targeted 1,703,639. Preparations are ongoing for upcoming rounds in National Capital Region (NCR) using bivalent OPV against poliovirus type 1 and 3 (targeting almost 1.3 million children under 5) and 6 regions of Mindanao using monovalent OPV against poliovirus type 2 (over 3.1 million children)