The period of greatest transmission of yellow fever is from December to March. Metropolitan regions of Rio de Janeiro, Minas Gerias and São Paulo are among the areas at risk of infection, Brazil health officials warned today.
The population living in areas recommended for the yellow fever vaccine should seek vaccination before the beginning of summer, the period of greatest risk of transmission of the disease. The Ministry of Health’s warning comes because recently affected areas and large population groups, such as the metropolitan areas of RJ, MG and SP, still have a large number of unvaccinated persons, that is, that are under risk of becoming ill. The disease has a high lethality, around 40%, which makes the situation more serious.
Since the outbreak recorded in December 2017, vaccination for yellow fever has been expanded to 4,469 municipalities. This was due to the inclusion of 940 cities located mainly in the capitals and metropolitan areas of the Southeastern and Southern regions of Brazil, where there was evidence of viral circulation. Vaccination coverage should be at least 95% of the population.
“We need to ensure that, especially in the municipalities of Rio de Janeiro and São Paulo, where many cases have occurred in the last two years, there is a preventive vaccination in anticipation of the summer when there is a greater circulation of the virus,” explains Carla Domingues, coordinator of the National Immunization Program.
The vaccine against yellow fever is offered in the National Vaccination Calendar and distributed monthly to the states. This year, 30 million doses of the yellow fever vaccine have already been sent throughout the country. Despite this availability, there is a low population demand for vaccination. People should take the dose at least 10 days before traveling to the recommended areas.
“The need for such preventive vaccination is crucial in yellow fever because if the majority of the population in these recommended areas is vaccinated, when the disease spikes in December, the need will be only of a vaccine block and we will not see rushing and huge queues in search of vaccine, “says Carla Domingues.
The target audience for vaccination are people from nine months of age who have no proof of vaccination. “We call on everyone in the recommended age group to seek vaccination rooms. It is no use to vaccinate one group and another not, since yellow fever is a disease transmitted by an infected mosquito and it can sting anyone. We should not wait for the onset of the disease, “emphasizes Carla Domingues.
Since April 2017, Brazil has adopted the vaccine’s single dose regimen, as recommended by the World Health Organization, supported by studies that ensure that one dose is sufficient for lifelong protection.
According to the new epidemiological bulletin, from July 1 to November 8 of this year, 271 suspected cases of yellow fever were reported, of which 150 were discarded, 120 remain under investigation and 1 was confirmed. Also in this period, 1,079 epizootics were reported in non-human primates. The new monitoring period is from July 1, 2018 to June 30, 2019. The data show the maintenance of viral circulation in the period of low occurrence (June to September), when low temperatures and rainfall usually imply in less favorable conditions to the transmission.
The report also confirms the first death from yellow fever in the second half of this year. The case was registered in São Paulo, with probable infection in the city of Caraguatatuba, where cases in monkeys (epizootics) had been detected months before the occurrence of the case. In this new monitoring period, epizootics have also been reported in monkeys in the states of São Paulo, Rio de Janeiro, Minas Gerais and Mato Grosso, where surveillance actions are under way.
In view of this, the Ministry of Health warns the health services network of epidemiological and environmental surveillance to anticipate the response and prevent the occurrence of the disease in humans. Among the guidelines for the intensification of surveillance are: to evaluate vaccination coverage in the municipalities of the Area with Vaccine recommendation (ACRV) and to vaccinate people from 9 months of age before the seasonal period of the disease; to guide travelers to the ACRV on the importance of preventive vaccination (at least 10 days before the trip), especially those who intend to carry out activities in wild or rural areas; to sensitize institutions and professionals from the health and extra health sectors (environment, agriculture / livestock, among others) on the importance of reporting and investigating death in monkeys.
In the previous monitoring period (from July 1, 2017 to June 30, 2018), 1,376 cases of yellow fever in the country and 483 deaths were confirmed. In total, 7,518 suspected cases were reported in this period, of which 5,364 were discarded and 778 were still under investigation. Since the beginning of the year (January 1 to November 8), 1,311 cases of yellow fever in the country and 450 deaths have been confirmed. In the same period last year, 795 cases and 262 deaths were reported.