New strain of dengue fever spreads
MATO GROSSO DO SOL, BRAZIL-Health authorities in Brazil say there has been a steep rise in the confirmed cases of dengue fever this year.
More than 200,000 people were infected in the first seven weeks of 2013 compared to 70,000 in the same period last year, official figures suggest.
The southern state of Mato Grosso do Sul has been hardest hit.
Officials said the cases were likely to rise as the rainy season increases the risk of reproduction of the mosquito which transmits the disease.
Health Minister Alexandre Padilha said that despite the higher incidence, the cases had been less severe than those recorded last year.
According to Mr Padilha, these figures showed that the authorities were following the right strategies in their fight against the fever.
He said extra training given to health care professionals and improvements to the network of basic care providers had clearly paid off.
But Mr Padilha warned state authorities not to let down their guard as the rainy season could exacerbate the situation, with standing water providing an ideal breeding ground for the mosquitoes carrying the disease.
Apart from Mato Grosso do Sul, seven other states across southern and central Brazil have been affected by the epidemic.
More than half of the cases have been caused by the DENV-4 strain of the virus, which was first detected in Brazil in 2011.
Mr Padilha said that because the strain was still relatively new to the country, more people were susceptible to infection.
There are four known types of dengue fever. Once people are infected by one type, they become immune to that variation, but not to other strains.
26 February 2013