RIO – At least 500,000 children in the country have not been vaccinated against polio. The Pan American Health Organization (PAHO) has listed Brazil as one of the eight Latin American countries with the highest risk of recurrence of the disease due to the high number of people without protection against the disease. In the most severe cases, the disease can cause paralysis.
According to Opas, a branch of the World Health Organization (WHO) in Latin America, low vaccination rates in these countries are a threat to the entire continent. No cases of the disease have been reported in the region since 1994. In Brazil, which already has 95% coverage of the polio vaccine, it is currently one of the lowest rates in its history, 67%, according to researcher Akira Homa, director of Biomanguinhos, from Fiocruz. He was responsible for eradicating the disease in the country in the 1980s.
“There are currently 500,000 children in our country who have not been vaccinated,” Homa said in an interview. Estadao. “This number is alarming, especially since we are close to Haiti and Bolivia, two countries with a high risk of infection.”
In Brazil, according to the National Immunization Program (PNI), children should be vaccinated with an injectable (inactivated virus) vaccine between the ages of two, four and six months. Then, they take two doses of oral immunosuppressant (live attenuated virus), the first at 15 months of age and the other at four years of age. According to official statistics, 67% of children had three doses of injectable vaccine. Oral vaccine coverage is even lower: 53%.
This does not mean that half of the children are completely unprotected. Even though the two regimes are incomplete, minors have some protection. However, from a public health point of view, according to Homer, it is ideal for all children to follow complete rules, both to prevent the transmission of the virus and to prevent possible mutations.
The injectable polio vaccine has been available in Brazil since 1973. But it was not until the 1980’s that the disease was finally eradicated in 1989, with the introduction of the oral vaccine and the national vaccine campaign (J. Gotinha was created for this activity). “We had the unity of the whole society,” Homa recalls. “We were able to vaccinate 18 million children in one day.”
In a note, the health ministry said it “closely monitors vaccination coverage and has worked to intensify strategies needed to reverse the low coverage scenario”. The folder also states that it recommends that states, municipalities, and federal districts conduct an active search for vaccines, and emphasizes the importance of maintaining routine immunizations. The ministry further said that dissemination of information on safety and efficacy of vaccines as a public health measure is also part of the ongoing work throughout the year.
Polio vaccination coverage was not so low?
Unfortunately, coverage of all vaccines, not just polio, has been steadily declining over five or six years, and more sharply, in the years leading up to the epidemic, even with the recommendation of social isolation. But the truth is that coverage has already fallen, not just in Brazil, but around the world. In 2019, the World Health Organization (WHO) named low vaccine coverage as one of the top ten public health problems in the world. The situation is really serious and very worrying because what we call the number of vulnerable people, the number of vulnerable people is increasing. Four weeks ago, we had a case of polio in Malawi, which is considered a polio free country. Most recently we found another case of polio in Israel, a country with a traditionally high vaccine coverage. There have been two imported cases.
Is there a real risk of polio returning to Brazil?
Yes, according to the Pan American Health Organization (PAHO) classification, polio imports exist and in Brazil, due to this low vaccine coverage, we are already considered a high risk country for re-infection. In addition, Brazil, Ecuador, Venezuela, Guatemala, the Dominican Republic and Suriname are in this category, with the exception of two other countries where the risk is considered high: Haiti and Bolivia. Note that we are surrounded by countries at risk of re-infection, and polio was considered eradicated throughout Latin America in 1994.
Polio is still an epidemic in which country?
In Pakistan and Afghanistan. The biggest problem, however, is the emergence of polio in the Middle East and other African countries where, due to low coverage, viruses derived from live attenuated vaccines are emerging.
Can you explain exactly how this process works?
The sabin vaccine (oral polio immunizer) is made from a live attenuated virus. Children who receive the vaccine spread the virus to the environment. With very little vaccination coverage, this virus can start circulating in immunized people. The more a virus is transmitted, the more mutations it goes through and it can become a new threat, as if it were a wild virus. If the vaccine coverage of the population is 95%, there will be no problem. But with so little coverage, it becomes a risk. In the case of Brazil, the coverage of injectable vaccines is 67%; That is, more than 30% of our children are unvaccinated. There are about 500,000 unprotected children. This is why PAHO has included Brazil among the countries at high risk for polio recurrence. The numbers are even more alarming because we are close to Haiti and Bolivia, two countries with a high risk of infection.
What is the reason for such low coverage in your analysis?
There are several reasons for this, there are many published works. One of the main reasons for this is that we are the victims of our own success. Since we do not have high incidence of the disease, the population does not see many cases, sick people do not see and people think they do not need to be vaccinated. It will not be necessary for the disease to be completely eradicated worldwide, but as long as there are polio-infected countries, we must continue to vaccinate children to prevent the entry of the wild virus into our country, especially with a high number of susceptible people. But I also think that the population needs to be better informed about the polio situation, people need to be called for vaccination, this transparent information is no more. There are also other issues that indicate the population, such as when opening a health center that coincides with working hours.
And what is the solution?
We are proposing a project to restore high immunization coverage by working in municipalities, where immunization plays a major role. We are following the daily routine in 41 municipalities of the two states, Amapa and Paraiba and based on these observations we will prepare a specific action plan for each city. The idea is to spread to the rest of the country.