| an outbreak of mayaro virus disease in belterra, brazil. iii. entomological and ecological studies. | results in entomological and vertebrate host investigations made during dual outbreaks of mayaro (may) and yellow fever (yf) viruses in belterra, pará, brazil in 1978 are reported. over 9,000 insects representing 26 species were assayed in 396 pools for the presence of arboviruses. pools of haemagogus janthinomys dyar yielded the only isolates of either may or yf virus. the minimum field infection rate for nine isolates of may virus from hg. janthinomys was 1:82, and for two isolates of yf virus ... | 1981 | 6266265 |