No abstract

The recent Zika virus (ZIKV) and chikungunya virus (CHIKV) epidemics highlight the explosive nature of arthropod-borne (arbo)viruses transmitted by Aedes spp. mosquitoes 1,2. Vector competence and the extrinsic incubation period (EIP) are two key entomological parameters used to assess the public health risk posed by arboviruses 3. These are typically measured empirically by offering mosquitoes an infectious bloodmeal and temporally sampling mosquitoes to determine infection and transmission status. This approach has been used for the better part of a century; however, it does not accurately capture the biology and behavior of many mosquito vectors which refeed frequently (every 2-3 days) 4. Here we demonstrate that acquisition of a second noninfectious bloodmeal significantly shortens the EIP of ZIKV-infected Ae. aegypti by enhancing Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

IMF programs, program evaluation, sample selection bias,

Quarterly evidence on participation in IMF programs for the period 1974-2003 is examined using the techniques of hazard analysis and error-correction estimation. Three hypotheses are proposed and tested. An increase in cumulative prior participation in IMF programs is found to cause a reduction on average in the length of a new spell of participation. The length of time between participation spells is reduced significantly with an increase in prior participation in IMF programs. Reserve adequacy is shown to be significantly and positively affected by participation in IMF programs. The results support a "revolving door" explanation of participation in IMF programs. Copyright by the President and Fellows of Harvard College and the Massachusetts Institute of Technology.