US scientists have discovered the most effective HIV antibodies to date, which could be used to find a vaccine for the virus, dpa quoted a study published in Science as saying today. A team of researchers coordinated by the National Institutes of Health (NIH) found the two proteins that can neutralize more than 90 per cent of known global strains of HIV. The VRC01 and VRC02 antibodies neutralize more strains with greater strength than any other previously known antibody, the study said. After finding out how the antibodies work and where they attach to the virus, the scientists have started developing a potential vaccine. They also said that their work could be used in HIV treatment. "In addition, the technique the teams used to find the new antibodies represents a novel strategy that could be applied to vaccine design for many other infectious diseases," said Anthony Fauci, director of the NIH's National Institute of Allergy and Infectious Diseases. An AIDS vaccine, which will prevent HIV infection as effectively as vaccines prevent polio and other viral infections, is still several years away. Vaccine development is expensive and daunting because HIV is like a moving target, mutating readily. Finding individual antibodies that can neutralize HIV strains is difficult because the virus is constantly changing its surface proteins to evade recognition by the immune system - resulting in a very large number of HIV variants worldwide. But the newly found antibodies "attach to a virtually unchanging part of the virus, and this explains why they can neutralize such an extraordinary range of HIV strains," said John Mascola, who led one of the study teams. The findings were published shortly before a large international AIDS conference that brings together scientists, international bodies and non-governmental advocates in Vienna from July 18.