Zika outbreak expected to end in 2 to 3 years

The researchers, whose work is published in the journalScience, estimated that infections from the mosquito-borne viruswill become so widespread in affected countries that populationswill develop what is called "herd immunity." This occurs when ahigh percentage of a population has become immune to aninfection either through developing natural immunity or throughvaccination, making a wider outbreak less likely.

"Because the virus is unable to infect the same person twicethanks to the immune system generating antibodies to kill itthe epidemic reaches a stage where there are too few people left to infect for transmission to be sustained," study author NeilFerguson of the School of Public Health at Imperial CollegeLondon said in a statement.

The study was based on mathematical models of the virus,which has been shown to cause microcephaly, a birth defectmarked by small head size that can lead to severe developmentalproblems in babies.

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The researchers compared data from Zika's transmissionacross Latin America to data on similar viruses, such as dengue,to create a model of projected Zika transmission. They forecastthat large-scale transmission will end in two to three years andnot resume for a decade.

Ferguson said it may be too late to try to control mosquitopopulations to prevent widespread Zika transmission, andmosquito abatement efforts might delay and prolong the outbreak,which will eventually die out naturally.