The vaccine coverage for measles, mumps and rubella, or the triple viral vaccine (SCR), has fallen significantly in Brazil and in the State of São Paulo over the last years and that may be one of the reasons for the current measles outbreak in the capital and the rest of the state, of which the first cases appeared on march, this year. The serotype circulating amongst the inhabitants of São Paulo is the D8, prevalent in European countries. Therefore, it is more likely the measles virus was reintroduced in São Paulo through cases from those countries and it’s less likely to be related to the cases from Venezuela, which led to an outbreak in the states of Amazonas and Roraima last year, according to Professor Marta Heloisa Lopes, of the Department of Infectious Diseases of FMUSP, and responsible for the Immunization Center of HCFMUSP and Head of the Immunology Laboratory of Medical Investigation (LIM 48).

The teacher has given the lecture “Measles – Upgrades” on August 9th for an audience of professionals, researchers and students, who crowded the Amphitheater Mario Camargo of the Tropical Medicine Institute of FMUSP.

The current cases of measles are less frequent among children. The most frequent group now is that of young adults from 15 to 29 years old, the target public of the recent campaigns of the Health Ministry. “The monovalent vaccine against the measles was licensed in Brazil in 1967 and systematically distributed as of 1973, and the triple viral (measles, mumps and rubella) only entered the calendar of the National Immunization Program in 1992. Consequently, many think they have been immunized in their childhood, but they are wrong”, said the professor.

The specialist demystified polemics round the security of the triple viral vaccine. “It’s an old vaccine, safe and with many researches on it. It doesn’t increase the risk of autism, neither it triggers the disorder in children prone to develop it. The affirmation is based on several researches; the most recent one has evaluated over 650 thousand children in Denmark”, she said.

The triple viral vaccine is contraindicated for pregnant women, children under six months old, gravely immunosuppressed people and those who received vaccines of live bacteria or virus over the last 30 days – which includes the SCR itself, besides yellow fever, varicella, BCG, oral polio or rotavirus. The immunoglobulin is only used for patients who can’t take the measles vaccine or who have had direct contact with a measles case – which is called post-exposure prophylaxis.

The coverage for the SCR vaccine in Brazil used to be about 90,19% in 2014 and dropped to 76% in 2018; in the State of São Paulo, it went from 98% to 81% in the same period. The Ministry of Health accounted for 1.226 cases of the infection from May 12th to August 3rd, of which 1.220 were in the State of São Paulo, four in Rio de Janeiro, one in Bahia and another in Paraná. The certification of a country free of the disease, obtained in 2016, was lost in 2018, when there was an occurrence of the same outbreak for over 12 months.

Preliminary data of the Pan American Health Organization (PAHO) show the notified cases of the measles in the world has grown 300% in the first three months of this year, compared to the same period in 2018. The tendency is the increase of cases, due to the low coverage (around 85% in the world), with the second dose having an even lower coverage, of 67%.