The Philippines has launched a polio immunization campaign and declared an outbreak in the country after confirming two cases in children and finding the virus in drains in two provinces, the country's health ministry said.
The confirmed cases ended a 19-year period when the country, with about 105 million, is considered polio-free, according to the World Health Organization (WHO).
It was officially declared free of the virus, which tends to affect children under the age of five and can cause irreversible paralysis within a few hours, 2000.
The outbreak comes when the Philippines is struggling with separate epidemics of measles and dengue fever that have killed more than 1
Health Ombudsman says fear of a trial of dengue fever vaccine, which health workers began administering in 2016 and then stopped the following year, has caused the vaccination rate for all types of virus to decline in recent years.  In the capital, polio vaccinations dropped from just over 77 percent of the target number in 2016 to below 24 percent in June, making the $ 13 million metropolis a high-risk area for polio recurrence, according to the Department of Health.
No known cure
The latest polio cases were confirmed in a five-year-old boy in Laguna, a province southeast of Manila, and a three-year-old girl in southern Lanao del Sur province, according to the Department of Health. The falls were approximately 1,400 km (870 miles) apart.
Polioviruses were also detected in Manila's wastewater and in the Davao region's waterways, located on the southernmost island of the Philippines.
Oyun Dendevnorov, Philippines Representative for the United Nations Children's Fund (UNICEF), called the re-emergence "deeply confusing".
Nineteen years after the country was declared polio free, Polio reappears in the Philippines.
I strongly urge parents, health care professionals and local authorities to fully participate in the synchronized polio vaccination and to exercise good personal hygiene. pic.twitter.com/r9IA6Y51Kg
– Secretary Francisco Duque III (@SecDuque) September 19, 2019
When agreed there is no cure and transmission can only be prevented by immunizations.  "As long as a single child remains infected, children across the country are at risk, and even beyond being affected by polio," she said in a statement released by the WHO on Thursday.
A global effort to eradicate polio has reduced infections from more than 350,000 cases in 1988 to just 33 last year, according to WHO data. Only Afghanistan, Nigeria and Pakistan have failed to stop the transfer.
Polioviruses have returned to the Philippines almost two decades of being #polio -free. UNICEF and @WHOPhilippines support @DOHgov outbreak response. READ: https://t.co/7x5RZBJJKt #VaccinesWork #EndPolio
– UNICEF Philippines (@unicefphils) September 19, 2019
In 2016, the Philippines became the the first nation to use Dengvaxia, the world's first dengue vaccine, in a national trial program with hundreds of thousands of schoolchildren
More than 830,000 children received the Dengvaxia vaccine during the campaign.
The government stopped immunization-driven 2017 after French manufacturer Sanofi said a study showed that the vaccine could increase the risk of serious dengue infections.
However, Sanofi officials maintained that the Dengvaxia vaccine was safe and would reduce dengue infections if the vaccination continued.  Nevertheless, the disclosure caused a nationwide panic, with some parents claiming that the vaccine killed their children, although an investigation conducted by the government found no conclusive evidence that it did.  The data on 119 dead children is being reviewed in an ongoing investigation to determine if Dengvaxia was to blame, a panel of medical experts said in March.
Immunization coverage in the Philippines is currently 70 percent, below the recommended 95 percent level, according to Rolando Enrique Domingo, a secretary at the country's health department.
In 2018, 12 of the 17 regions in the country were identified as high risk areas for polio reemergence, according to the Department of Health.
"The polio vaccinations happen year-round, but our coverage has dropped over the last five years," Domingo told Reuters news agency.
"We have learned our lesson. It is time to move on and really start to vaccinate all children and make sure we maintain this every year," he said.