Polio vaccination for stays in countries with polio outbreaks
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The World Health Organization (WHO) considers polio to be an international public health crisis, and a goal has been set to eradicate the disease. There has been a reduction in the number of reported cases, but the WHO still considers the risk of the spread of polio to be of concern.
It is important to get vaccinated before travelling to countries with an ongoing or recent outbreak of polio, to prevent infection in the individual and further transmission of the virus. The Norwegian Institute of Public Health recommends that everyone should be protected against against diphtheria, tetanus, pertussis and polio, and receive a booster dose every 10 years.
Current recommendations
As of August 2023, the recommendations apply to the following countries:
- Afghanistan, Algeria, Benin, Botswana, Burkina Faso, Burundi, Canada, Central African Republic, Djibouti, DR Congo, Egypt, Ivory Coast, Eritrea, Ethiopia, Gambia, Ghana, Indonesia, Israel, Yemen, Cameroon, Kenya, Mali, Malawi, Madagascar, Mauritania, Republic of Congo, Mozambique, Niger, Nigeria, Pakistan, Senegal, United Kingdom, Somalia, Sudan, Tanzania, Togo, Chad, Uganda, Ukraine, USA and Zambia.
- Statement of the thirty-sixth Polio IHR Emergency Committee (WHO August 2023)
Vaccination advice when staying in countries with an incidence of polio and countries that are vulnerable to new introductions of polio
Countries with outbreaks of wild poliovirus or vaccine-derived poliovirus type 1 or type 3
Countries at risk of exporting wild poliovirus or vaccine-derived polio type 1 or 3 must ensure that everyone departing from the country has received the polio vaccine. This is in addition to an intensification of the polio vaccination of the population.
As of August 2023, this applies to:
- Wild poliovirus: Afghanistan, Pakistan, Malawi and Mozambique
- Vaccine-derived poliovirus type 1: Madagascar, Mozambique, Malawi, DR Congo and Republic of Congo
- Vaccine-derived poliovirus type 3: Israel
To prevent export of infection from these countries, you must have received the polio vaccine between 4 weeks and 12 months before leaving the country. This applies to visitors who will be staying in the country for more than 4 weeks. The vaccination must be documented with an international vaccination certificate.
The vaccination advice applies to people of all ages. Children must also be vaccinated against polio during the last 12 months before departure from these countries, even if they are considered fully vaccinated according to the Norwegian childhood immunisation programme. When infants are going to travel to the above-mentioned countries, the public health nurse/ doctor at the public health clinic should consider bringing forward the vaccination and possibly switching to a 4-dose programme for infants who will otherwise not have time to receive two doses of polio vaccine before departure. Polio vaccine is given at vaccination clinics, public health clinics or by general practitioners.
Wild poliovirus is currently only endemic in Pakistan and Afghanistan. Recent confirmed cases of wild poliovirus in Malawi and Mozambique are considered to be imported because of their genetic similarity to poliovirus found in Pakistan.
Countries with prevalence of vaccine-derived poliovirus type 2
For travel to countries with prevalence of vaccine-derived poliovirus type 2, it is important to ensure up-to-date polio vaccination and to consider bringing forward the vaccination of infants. The WHO and Norwegian health authorities encourage visitors with a stay of more than 4 weeks in countries with polio outbreaks, who are at risk of exporting vaccine-derived poliovirus type 2, to follow the same advice as for countries with outbreaks of wild poliovirus or vaccine-derived poliovirus type 1 or type 3 (see above).
As of August 2023, several countries have prevalence of vaccine-derived poliovirus type 2: Algeria, Benin, Botswana, Burkina Faso, Central African Republic, DR Congo, Ivory Coast, Ghana, Indonesia, Israel, Yemen, Cameroon, Kenya, Malawi, Mali, Mozambique, Niger, Nigeria, Republic of Congo, Somalia, Sudan, United Kingdom, Togo, Chad, USA and Zambia.
The polio outbreaks in Yemen, DR Congo, Nigeria and Somalia account for 70 per cent of all disease cases worldwide.
In July 2022, the WHO reported a polio case with paralysis in an unvaccinated person in Rockland County, in the state of New York, USA. Related viruses have also been detected in sewage in Montreal (Canada), London (UK) and in Jerusalem (Israel) in 2022, suggesting transmission across national borders in connection with travel.
Vaccination coverage in Canada, the United States, United Kingdom and Israel is generally high, but the virus has been detected in areas with under-vaccinated population groups. The virus has been able to circulate and regain its disease-causing properties. Vaccination campaigns have been launched and monitoring heightened in these countries.
Countries without detected cases but vulnerable to reintroduction of poliovirus
Canada, Djibouti, Egypt, Eritrea, Ethiopia, Gambia, Mauritania, Senegal, South Sudan, Uganda and Ukraine are considered by the WHO to be at risk of new introduction of vaccine-derived poliovirus, even though they currently have no reported cases of polio. In Ukraine, two polio cases with paralysis were reported in 2021.
For travel to these countries, it is still important to ensure up-to-date polio vaccination, although the same applies to many other bordering countries.
About polio and polio vaccine
Polio (poliomyelitis) is a viral disease that can be eradicated with a vaccine because the virus is only detected in humans. Over 90 per cent of those infected have no symptoms, 9 per cent have influenza-like symptoms, while less than 1 per cent develop paralysis. The paralysis can occur in muscles anywhere in the body and can be fatal. The last major polio epidemic in Norway occurred in the mid-1950s, and the last domestic polio infection occurred in 1969. Use of the polio vaccine has led to the disease being under control in most parts of the world, and the WHO's European region was declared polio-free in 2002.
There are two types of polio vaccine, an inactivated (IPV - used in Norway) and a live, weakened oral vaccine (OPV) which is used in many countries. Vaccine-induced polio disease can only occur with the use of the live, attenuated polio vaccine, and is rare. In a population with low polio immunity, vaccine virus may begin to circulate, and in a few cases gradually regain the ability to cause polio with paralysis (circulating vaccine-derived poliovirus (cVDPV)).