Philippines: Re-emergence of vaccine preventable diseases - Revised Emergency Plan of Action (EPoA) n° MDRPH032

Situation Report
Originally published


A. Situation analysis

Description of the disaster

On 19 September 2019, the Department of Health (DOH) confirmed the re-emergence of polio (vaccine-derived poliovirus, VDPV) in the Philippines and declared a national polio outbreak. The re-emergence comes almost 20 years after the Philippines had been declared polio-free in 2000 and the last case of wild poliovirus was recorded in 1993.

Children below the age of five – particularly in urban slums or rural areas, from families of overseas Filipino workers, families continuously on the move (e.g. Bajjao), intra-country circular migrants or indigenous communities – suffer from prolonged vulnerability and disadvantage resulting in a chronic humanitarian situation with increased risk for preventable disease and death.
Underlying conditions for this situation include low vaccination coverage, unsafe water, poor sanitation, poor living conditions and lack of access to health services.

Since late 2018, there has also been a dramatic increase in localized measles outbreaks across the country. Since the national measles outbreak was declared, there have been at least 42,004 cases and 563 deaths reported between 1 January and 28 September 2019. In the same period for 2018 there were 14,985 cases 128 deaths with an overall total of 202 deaths in 2018. Most deaths are children with a median age of one-year-old.

The declaration of a polio outbreak followed a confirmed Vaccine Derived Poliovirus Type 2 (VDPV2) case in a three-year old child in Lanao de Sur (Mindanao) reported on 16 September 2019. Subsequently, another VDPV2 case of polio was confirmed on 20 September, this time in a five-year-old boy who was immunocompromised from Laguna which is adjacent to Metro Manila.

In addition, between 1 July and 27 August 2019, four environmental samples tested positive for VPDV1 from Tondo (Manila) with no genetic linkage found with any known VDPV1, indicating new emergence. Between 13 and 22 August 2019, two environmental samples tested positive for VDPV2 from Tondo (Manila) and Davao City. Both Type 2 samples were found to be genetically linked. As a result, VDPV2 was classified as circulating (cVDPV2). Please refer to Table 2 for the latest information on the samples confirmed (as of 25 October 2019).

Today, only three countries in the world have not been able to stop the circulation of wild polio virus (Pakistan, Afghanistan, Nigeria). The rest of all other outbreaks are caused by vaccine-derived polio virus. Not only the Philippines, but altogether five countries namely China, Papua New Guinea and Philippines (in the WHO Western Pacific region) and Indonesia and Myanmar (in the WHO Southeast Asia region) as well as Angola, Benin, Central African Republic, Congo, Ethiopia, Mozambique and Somalia (WHO Africa region) have declared outbreaks of Vaccine Derived Polio Virus in 2019. If outbreaks are not ended quickly and if the routine immunization coverage is not improved to at least 95 per cent, the at-risk countries may hinder the objective of ending polio. Consequently, globally it may take much resources and many years to contain the deadly virus, once again.

Poor immunization coverage is the root cause of the measles and polio outbreaks. The spread of Polio are facilitated by poor quality water and sanitation systems. Underlying factors for poor immunization coverage include supply issues (sustained and consistent vaccine availability, logistics, access to services) as well as demand issues (health literacy, vaccination fatigue, compliance). It is reported that children fully immunized for measles dropped over the last five years from 91 per cent to less than 40 per cent. In 2018 the estimated polio vaccination coverage2 for children in the Philippines less than one year old with the required three doses of bivalent oral polio vaccine (bOPV) was 66 per cent, far below the population-level coverage needed to prevent sustained transmission of polio. For inactivated poliovirus vaccine (IPV, introduced in 2016), coverage was 41 per cent.

The highly contagious nature of childhood vaccine-preventable diseases, coupled with the low vaccination rate and lack of herd immunity, has resulted in and will continue to foster multiple outbreaks. Marginalization of families, with poor health literacy and knowledge about disease transmission are a root cause as well. The environmental conditions in poor dense and congested urban and isolated hard-to-reach rural communities, all with poor hygiene and sanitation, have exacerbated the situation promoting the rapid spread of these diseases. These outbreaks represent acute phases of a chronic humanitarian situation, hence the required rapid humanitarian response.

In response to the polio outbreaks, the DOH is planning three vaccination rounds targeting 3,111,650 under-five children with monovalent Oral Polio Vaccine against poliovirus type 2 (mOPV2) in affected areas of Mindanao Lanao del Sur (including Marawi City), Davao del Sur and Davao City. DOH is also planning two vaccination rounds targeting 1,276,631 under-five children with bivalent Oral Polio Vaccine (bOPV) in the National Capital Region (NCR). Enhanced immunization with three doses of bOPV as well as inactivated poliovirus vaccine (IPV) nationwide is ongoing.

A combination of effective outbreak acute response with high coverage of Outbreak Related Immunization, of scaled-up surveillance and care for the sick at the community level may bring back the herd immunity and improve health protection for children under five in the Philippines, but this will not be enough to prevent future outbreaks or sustain protection of future children.

PRC will continue to provide home-based support for children with suspected Acute Flaccid Paralysis (polio) – including support for disability of paralyzed children (in keeping with principles of protection, gender and inclusion); as well as undertake mass vaccination, perform social mobilization, health and hygiene promotion, health education and to improve coverage of outbreak related immunization. Using community networks, PRC will also support disease surveillance efforts as requested by the government.

For the longer-term interventions, PRC will focus on micro-planning with the Red Cross 143 volunteer network to address context specific challenges in disadvantaged communities. For example, in areas where teenage pregnancy is high and young mothers are not empowered to avail of health services, actions will be taken to address low health literacy and ensure protection of girls. In areas where poor hygiene and lack of sanitation increases vulnerability, PRC will work toward household and community interventions for WASH.

The project will support PRC Epidemic Preparedness to better prepare PRC NHQ and chapters to respond to localized outbreaks and inform them better through better data governance and risk modelling. The Epidemic Preparedness (EP2) initiative will also document and disseminate learnings especially in the Asia Pacific (AP) region to help prepare other national societies for any outbreak.