Why does Brazil have no cases of measles? – 02/15/2024 – Balance and Health

Brazil is experiencing a certain calm when it comes to measles. According to the Ministry of Health, no new cases of the disease have been recorded since 2022, and vaccination coverage has increased by more than 10% in the last two years.

In other parts of the world — such as Europe and some parts of the United States — the situation is opposite: there is a growing wave of cases and even deaths. There has been a 45-fold increase in the number of virus infections in European countries.

The epidemic situation caused the United Kingdom’s Health Security Agency to classify measles as a “national incident”.

But what explains this difference? And what does Brazil need to do (or continue to do) to prevent the measles situation from worsening in the country?

What happens in Europe

In December last year, the World Health Organization (WHO) office in Europe classified the increase in measles cases on the continent as “alarming”.

In 2023, this region recorded 42,200 new infections due to this virus. The previous year, there were less than a thousand cases.

The WHO points out that the rate of new patients has accelerated recently — and is expected to continue to rise if “urgent measures are not taken to prevent future spread.”

As mentioned at the beginning of the report, the United Kingdom’s Health Security Agency classified the measles emergency as a “national incident”.

An article published by the academic journal Nature links this scenario to the drop in vaccination rates in European countries.

“Around 85% of British children under the age of five have received two doses of the MMR vaccine,” the text points out.

Authorities estimate that it is necessary to vaccinate at least 95% of the population to guarantee herd immunity, that is, a level of collective protection that prevents outbreaks and epidemics.

Among the factors for the low rate of vaccinations, Nature cites the Covid-19 pandemic — which disrupted many people’s immunization schedules — and the spread of false news about doses that protect against measles and other various infectious diseases.

On January 22, the UK public health service launched a vaccination campaign to contain the crisis.

In addition to asking parents and guardians to take their children to take the doses, health professionals will contact families whose children aged 6 to 11 are unprotected from measles.

The United States has also recorded cases of the disease in recent weeks, although the numbers are much lower when compared to Europe.

Between December 1st and January 31st, there were 23 diagnoses spread across Georgia, Missouri, New Jersey and Pennsylvania.

Worldwide, measles cases grew 18% between 2021 and 2022, says Nature.

The WHO also warns that deaths from the disease rose 43% in the same period.

What happens in Brazil

In 2016, the Pan American Health Organization (PAHO), which represents the WHO on the American continent, gave Brazil a measles elimination certificate.

The news, much celebrated at the time, confirmed that the country was free of the virus, thanks to decades of vaccination campaigns and surveillance and case detection programs.

But, in 2019, Brazil lost its certificate due to an outbreak that spread across several states.

In 2016 and 2017, Brazil did not even have a case of measles.

In 2018, there were more than 9,300 infections. The following year, the number rose to 20,900 and remained high in 2020, with 8,100 cases.

The scenario began to improve in 2021 and 2022 — and the country again recorded no measles infections in 2023.

These case curves can be largely explained by vaccination, point out experts interviewed by BBC News Brasil.

Vaccination coverage with the first dose of this vaccine was practically 100% between 2010 and 2014.

In 2015 and 2016, rates began to fall, but still within the 95% limit recommended by health agencies to guarantee herd immunity.

It was during this period that measles cases ended, and the country gained the elimination certificate.

From 2017 onwards, however, the situation became more complicated: with small variations, vaccination coverage fell little by little and reached an alarming 74.9% in 2021.

In practice, this meant that a quarter of Brazilian children were unprotected from a highly contagious and potentially fatal disease. With the population lacking immunity, an epidemic broke out.

The situation began to improve from 2022, when vaccination coverage reached 80.7%.

Last year, this rate increased to 85.6% — which was greatly celebrated by the Ministry of Health.

“I want to say that the vaccination movement won. We all achieved together the objective of reversing the downward trend in vaccination coverage. Society answered the call and included itself in this movement”, minister Nísia Trindade spoke in December.

“I would like to remember what the WHO has already said: the vaccine, together with treated water, is what guaranteed the reduction in child mortality and the increase in expectations around the world.”

Pediatrician Mônica Levi, president of the Brazilian Society of Immunizations (SBIm), assesses that there was recently a restructuring of the National Immunization Program (PNI) of the Ministry of Health, which helped in the recovery of vaccination rates.

“There is still a lot to be done to restore the 95% rate, but at least we see a reversal in the downward trend of recent years”, says the expert.

Doctor Eliana Bicudo, advisor to the Brazilian Society of Infectious Diseases, says that the vaccination situation is improving, but is still far from ideal.

“We still can’t put our head on the pillow and be carefree about measles. If we do that, this outbreak in Europe will catch us with our pants down”, warns the infectious disease specialist.

A new measles elimination certificate?

The fact that Brazil has been without new cases of measles for more than a year has rekindled hopes that the country will once again be declared a territory free of this virus.

The director of PAHO himself, Brazilian doctor Jarbas Barbosa, spoke about the subject in a lecture in Rio de Janeiro in December last year.

“Brazil has already been without any new cases diagnosed for a year, which also allows us to have great hope that, in the coming months, the verification commission will be able to certify the country again,” he said.

But Levi remembers that not registering new infections for a while is not the only decisive factor in becoming a measles-free territory.

“It is important to have homogeneity in vaccination, that is, to have all regions of the country with a high rate of immunized people, without many differences in this percentage from place to place”, highlights the doctor.

The president of SBIm also highlights the need for an active surveillance system, capable of quickly detecting patients with the virus who arrive in the country through ports, airports and borders.

A practical example of this type of action happened recently: on December 26th, a 3-year-old boy came with his family to Brazil from Pakistan.

He began to show some symptoms and was treated at a health unit in Porto Alegre on January 2, when he was placed in isolation. Tests confirmed that he had measles.

Cases imported from other places, like this episode with the boy coming from Pakistan, are not counted as local infections, which occurred in Brazil — but they raise a warning signal.

And there is a whole protocol — which involves early detection of measles, isolating the patient, vaccinating people who have had contact with them and monitoring the health of those involved — to prevent the disease from spreading and generating a new wave of transmissions. .

“And we need to have this entire system well structured to once again be a country that has eliminated measles”, reinforces Levi.

The unstable measles scenario in other parts of the world made PAHO sound the alarm last week.

The entity called on all countries in the Americas to “intensify vaccination activities, epidemiological surveillance and rapid response preparation for possible outbreaks.”

A highly contagious disease

Bicudo explains that measles is an infection caused by a virus, which is transmitted from one person to another through the airways (through coughing, sneezing and runny nose) or through contact with contaminated surfaces.

This microscopic agent has a high contagion capacity. It is estimated that someone infected can transmit measles to 12 or 18 other people.

“Measles causes damage to the airways, with symptoms of fever, body pain, headache, nasal congestion, spots on the skin, tearing, coughing, conjunctivitis and otitis”, lists Bicudo.

“In more serious situations, it can lead to pneumonia or even meningoencephalitis (an infection in the central nervous system), especially in more vulnerable patients.”

These cases are worrying and, without the necessary care, can lead to death.

There is no specific treatment against measles. Doctors prescribe medicines to alleviate discomfort and provide life support in the most serious cases.

The main way to stay protected against this virus is the vaccine. In Brazil, the Ministry of Health and SBIm recommend a two-dose schedule.

The first must be done at 12 months of age and uses triple viral, an immunizer that protects not only against measles, but also against mumps and rubella.

The second is carried out 90 days later, when the child turns 15 months old and receives tetraviral medication (which protects against measles, mumps, rubella and chickenpox).

For those who missed this deadline, there are no problems: you can take these vaccines at any time in your life.

Until the age of 29, the recommendation is to follow the two-dose schedule. Between the ages of 30 and 59, health authorities recommend the application of just one dose of the MMR.

The vaccine is available on the public network and there is no need for boosters: anyone who has taken two doses after turning one year old is protected for the rest of their life.

The high contagion capacity of measles requires that a large part of the population be vaccinated to create herd immunity, in which everyone is protected from an outbreak or epidemic.

“It is necessary for 95% of people to be vaccinated to ensure that that population is truly protected from this virus”, reinforces Bicudo.