Poliomyelitis


Background

In human history, poliomyelitis has caused tremendous trauma to numerous individuals and families and brought about immense loss of human lives as well as material resources. In an effort to minimize the damage caused by poliomyelitis and free humanity from the threat of the disease, the World Health Organization (WHO) launched the Global Polio Eradication Initiative in 1988. Since its inception, the program has achieved outstanding results with the efforts and cooperation of so many countries. In 2018, global poliomyelitis cases caused by wild polioviruses had fallen to 33, bringing the world close to the eradication objective.

Though the threat posed by poliomyelitis to human beings has been significantly reduced, for countries that have eradicated polio, the disease still poses a huge challenge to public health when wild poliovirus (WPV) is detected in patients. If poliomyelitis occurs in countries where polio vaccination rates are low, it becomes an even greater threat. Consequently, as long as poliovirus still spreads in certain countries, the risk of polio being imported from other countries cannot be completely eliminated and the challenge and threat will continue to exist. Afghanistan, Nigeria, and Pakistan are the only three countries that have never interrupted endemic transmission of WPV and pose a risk for polio outbreaks in polio-free regions of the world. A WPV outbreak occurred in Syria and Iraq during 2013–2014 after importation of a poliovirus strain circulating in Pakistan. The outbreak represented the first occurrence of polio cases in both countries in approximately a decade, and resulted in 38 polio cases, including 36 in Syria and two in Iraq. It shows that even in the polio-eradicated countries, polio can still occur and erupt into epidemics once again.

Furthermore, vaccine-derived polioviruses(VDPVs) pose a great threat to countries with low vaccination rates. Poliomyelitis has been eradicated in Taiwan since 2000. Nevertheless, frequent travel by Taiwanese businessmen to and of foreigners from regions where poliomyelitis is still common due to trade and personal reasons has furthered the transmission of poliovirus. As a result, it is rather difficult to prevent poliovirus from transmitting from other countries into our territory before the global eradication objective is reached. Therefore, even though it is unlikely that a polio epidemic might break out in Taiwan, we still need to be well-prepared at peacetime so that when an epidemic occurs, we may immediately detect it and effectively prevent its spread.

Epidemiology

Taiwan has not seen confirmed poliomyelitis cases caused by WPV infection since 1983. Poliomyelitis eradication was declared in the Western Pacific area where Taiwan is located in 2000.
Poliomyelitis Surveillance in Taiwan

National Notifiable Disease Surveillance System

  1. Poliomyelitis (Polio)
  2. Acute flaccid paralysis (AFP) 

Prevention and Control

1. AFP surveillance
In order to fulfill the global goal of eradicating poliomyelitis, AFP surveillance was instituted in Taiwan in 1994, as recommended by WHO. AFP surveillance is the gold standard for detecting cases of poliomyelitis, and also critical for documenting the absence of poliovirus circulation for polio-free certification. Whenever a suspected AFP cases must reported to the competent health authority for further examination and investigation.

2. Environmental surveillance
Environmental surveillance has been implemented following the WHO guideline through research projects that began in July 2012. From July 2012 to July 2019, none poliovirus was identified.

3. Routine immunization
(1)   A 5-dose OPV schedule was included in the routine childhood immunization schedule in Taiwan as advised by the Taiwan ACIP since 1983. In order to improve the quality of immunization service, the government has introduced DTaP-Hib-IPV into the national childhood immunization program with a 4-dose schedule targeting children at the age of 2, 4, 6, and 18 months.
(2)   In April 2012, Taiwan CDC revised the recommended childhood immunization schedule for Tdap-IPV vaccination to be administered at 5 years of age rather than when entering elementary school. This change encourages preschool children to get vaccinated at contracted hospitals/clinics instead of in school.(Tdap-IPV was replaced with DTaP-IPV in October 2017)

4. Current response strategies to the WHO’s declaration of polio as a Public Health Emergency of International Concern

(1)   Communication with the public and travel industry
Taiwan CDC issued press releases and the “International Epidemic Bulletin” to ensure travelers and travel industry could obtain adequate health information including introduction to poliomyelitis, vaccination recommendation and immunization requirement to and from affected countries.

(2)   Updating polio vaccination recommendations
The Taiwan Advisory Committee on Immunization Practices (ACIP) issued vaccination recommendations for travelers based on the WHO’s Temporary Recommendations. For those who visit countries with active poliovirus transmission, polio vaccination administration should be documented on an International Certificate of Vaccination or Prophylaxis (ICVP).

(3)   Health education for travelers
Taiwan CDC provides travelers updated health information on its official website. There are 32 contracted travel clinics providing pre-travel medical consultation and inactivated polio vaccine administration.

FAQs

1.      What is polio?
Polio (or poliomyelitis) is a disease caused by poliovirus. It can cause lifelong paralysis (can’t move parts of the body), and it can be deadly. But, the polio vaccine can protect against polio.

2.      What are the symptoms of poliovirus infection?
Most people who get infected with poliovirus do not have any symptoms.
In rare cases, poliovirus infection can be very serious. About 1 out of 100 people will have weakness or paralysis in their arms, legs, or both. This paralysis or weakness can last a lifetime.

3.      How serious is polio?
The risk of lifelong paralysis is very serious. Even children who seem to fully recover can develop new muscle pain, weakness, or paralysis as adults, 30 or 40 years later.
About 2 to 5 children out of 100 who have paralysis from polio die because the virus affects the muscles that help them breathe.

4.      How does polio spread?
Poliovirus is very contagious. The virus lives in an infected person’s throat and intestines. It spreads through contact with the feces (stool) of an infected person and through droplets from a sneeze or cough. You can get infected with polio if you have stool on your hands and you touch your mouth. Also, if you put objects, like toys, that have stool on them into your mouth, you/your baby can get infected.
An infected person may spread the virus to others immediately before and usually 1 to 2 weeks after developing symptoms. The virus may live in an infected person’s feces for many weeks. It can contaminate food and water when people do not wash their hands.

5.      What is the polio vaccine or IPV?
IPV is a type of polio vaccine. IPV stands for inactivated polio vaccine. It is given by a shot.
Polio vaccine protects children by preparing their bodies to fight the polio virus. Almost all children (99 children out of 100) who get all the recommended doses of IPV will be protected from polio.

6.      What can I do to protect my child from polio?
Vaccinate your child on time. Talk with your child’s doctor if you have questions. Keep a record of your child’s vaccinations to make sure your child is up-to-date.

7.      When should my child get the polio vaccine?
(1) Children should get four doses of DTaP-Hib-IPV at the following ages for best protection:

A.     First dose at 2 months.

B.     Second dose at 4 months.

C.     Third dose at 6 months.

D.     Fourth dose at 18 months

(2) And One booster dose of DTaP-IPV at 5 years.

※It is safe to get IPV at the same time as other vaccines.

8.      Is the polio vaccine safe?
IPV is very safe and effective at preventing polio. Vaccines, like any medicine, can have side effects. But, severe side effects from IPV are very rare.

9.      If my child does not get the polio vaccine, will he get polio?
Without the vaccine, polio spreads very easily. Before the polio vaccine, more than 400 people became paralyzed from polio in Taiwan each year. Today, thanks to the vaccine, there is no more polio in Taiwan. But, if people stopped vaccinating, we could see cases of polio again.

10.  How can I learn more about the polio vaccine?
To learn more about the polio vaccine or other vaccines, talk to your child’s doctor, call the toll-free 1922 (or 0800-001922) hotline or visit the website of Taiwan CDC.

More Information

  1. WHO|Poliomyelitis (polio)
  2. Global Polio Eradication Initiative
  3. USA CDC|Polio
  4. USA CDC|Polio Vaccination

 

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發佈日期 2014/11/24