If zika causes brain deformations, microcephaly, how come this epidemic is restricted to Brazil, asks a New England medical think tank.
There are 1,500 confirmed cases of microcephaly in Brazil, but in Colombia, a study of nearly 12,000 pregnant women infected with zika found zero microcephaly cases, said the New England Complex Systems Institute.
The institute describes itself as an independent academic research and educational institution with students, postdoctoral fellows and faculty with additional faculty, students and affiliates from Massachusetts Institute of Technology, Harvard, Brandeis and other universities nationally and internationally.
Although there are at least five cases of pregnant women with zika in Costa Rica, there are no diagnosis of microcephaly, according to the Ministerio de Salud.
Microcephaly and Guillain-Barré syndrome have been attributed
to zika infection. However, the New England Institute study said that the zika-microcephaly link should be reconsidered.
“One possibility that has been raised is the pesticide pyriproxyfen, which is applied to drinking water in some parts of Brazil to kill the larvae of the mosquitos that transmit zika,” the institute said in its report.
In April the U.S. Centers for Disease Control and Prevention and other agencies said that the medical consensus was that zika caused microcephaly. Pregnant women were advised not to visit areas where zika is prevalent and urged to exercise birth control if they are not pregnant and visiting. The presence of slightly more than 100 cases in Costa Rica is expected to have an impact on tourism.
The New England institute based its study on one published in the New England Journal of Medicine that said there were no cases of microcephaly among 12,000 pregnant women in Colombia as of May 2. At the same time four cases of microcephaly were reported there of women who were not infected.