Continued improvement in stent-graft design, including branched endografts, will reduce but not eliminate multi-stage procedures. Percutaneous EVAR
Standard EVAR involves a surgical cut-down on either the femoral or iliac arteries, with the creation of a 4–6 cm incision. Like many surgical procedures, EVAR has advanced to a more minimally invasive technique, by accessing the femoral arteries percutaneously In percutaneous EVAR (PEVAR), small, sub-centimeter incisions are made over the femoral artery, and endovascular techniques are used to place the device over a wire. Percutaneous EVAR has been systematically compared to the standard EVAR cut-down femoral artery approach. Moderate quality evidence suggests that there are no differences in short-term mortality, aneurysm sealing, long and short-term complications, or infections at the wound site. Higher quality evidence suggests that there are no differences in post-repair bleeding complications or haematoma between the two approaches. The percutaneous approach may have reduced surgical time. Fenestrated EVAR
In certain circumstances, a specially designed custom-made graft, which has holes, or fenestrations, on the graft body to maintain the patency of the visceral arteries, is used for the procedure, which is called FEVAR (fenestrated endovascular aortic/aneurysm repair). When the aneurysm begins close to the renal arteries, standard EVAR may be contraindicated since there will be an inadequate length of suitable aorta for the endograft attachment. In these cases, a fenestrated endograft may be useful, where the attachment of the endograft to the aorta may be placed above the renal arteries with each fenestration aligned with a renal artery so that blood flow to the kidneys is maintained.
The hemagglutinin sequences of most of the H5N1 avian influenza viruses circulating in the past few years fall into two genetic groups, or clades. Clade 1 includes human and bird isolates from Vietnam, Thailand, and Cambodia and bird isolates from Laos and Malaysia. Clade 2 viruses were first identified in bird isolates from China, Indonesia, Japan, and South Korea before spreading westward to the Middle East, Europe, and Africa. The clade 2 viruses have been primarily responsible for human H5N1 infections that have occurred during late 2005 and 2006, according to WHO. Genetic analysis has identified six subclades of clade 2, three of which have a distinct geographic distribution and have been implicated in human infections:

Subclade 1, Indonesia
Subclade 2, Middle East, Europe, and Africa
Subclade 3, ChinaOn the basis of the three subclades, the WHO is offering companies and other groups that are interested in pandemic vaccine development these three new prototype strains:

An A/Indonesia/2/2005-like virus
An A/Bar headed goose/Quinghai/1A/2005-like virus
An A/Anhui/1/2005-like virus[...] Until now, researchers have been working on prepandemic vaccines for H5N1 viruses in clade 1. In March, the first clinical trial of a U.S. vaccine for H5N1 showed modest results. In May, French researchers showed somewhat better results in a clinical trial of an H5N1 vaccine that included an adjuvant. Vaccine experts arent sure if a vaccine effective against known H5N1 viral strains would be effective against future strains.