By Lise Alves, Senior Contributing Reporter
SÃO PAULO, BRAZIL – After the confirmation of at least twelve deaths since 2017 from yellow fever in the São Paulo metropolitan area, health officials have announced a massive vaccination campaign against yellow fever in February. Authorities say that the vaccine given during the campaign, however, will be ‘fractionized’, or divided into four doses.
“There is no difference in efficacy between fractional and integral vaccines. What we are discussing is the time it endures by protecting at the level of sufficient antibodies for number of years,” noted David Uip São Paulo state’s Health Secretary, trying to dissipate rumors that there may not be enough vaccines to go around.
The fractionated dose was defined by a Ministry of Health directive, and has proven efficacy for eight years, while the full dose lasts a lifetime. According to officials, however, children between nine months and two years, pregnant women in risk areas, those with renal and diabetes problems and those travelling to countries where the vaccine is required, will be given the full dose.
“The expectation is that, with the fractionated dose about 4.5 million people will be vaccinated with another 1.5 million will be given the full dose,” explained Rejane de Paula, director of the Center for Epidemiological Surveillance for São Paulo state during a press conference earlier this week.
The campaign will run from February 3rd to 24th and target 53 cities including the capital, São Paulo city. Meanwhile authorities urge residents who haven’t been vaccinated to avoid parks and wooded areas where the mosquito carrying the yellow fever virus may be found.
Last October thirteen parks in the city were closed for precaution after monkeys contaminated with the yellow fever virus were found dead in the area. In late December another ten urban parks in the south and west of São Paulo city were closed indefinitely, ‘as a measure to prevent the spread of yellow fever’, according to officials.