Born in 1944, Sylva grow up in a traditional Jewish Zionist family in Riga. When Sylva was 20, she started her Zionist activity which included spreading Hebrew teaching books to USSR Zionist groups in different cities. She graduated with a degree in engineering from the Riga Polytechnic University.
Sylva had dreams of making a home in Israel. At the age of 25, in 1970, after repeatedly being denied exit from the Soviet Union, Sylva, her husband then Edward Kuznetsov, two brothers and 12 other Zionist activists, were arrested by the KGB for an escape attempt from the USSR. It is known as the “Dymshits-Kuznetsov Hijacking Affair” or “The First Leningrad Trial” or “Operation Wedding,” a code name for a plan to take an empty plane outside the Soviet borders, over to Sweden, bound for Israel.
Young, fearless, and the only woman in the dock, Sylva was ordered to stand and state her case. She proclaimed: “Even here, on trial, I still believe I’ll make it someday to Israel. This dream, illuminated by 2,000 years of hope, will never leave me. Next year in Jerusalem!” The first Leningrad trial was broadcast around the world, creating furious street protests in America, Australia, Europe, and Israel, triggering an international outcry from 24 governments. Sylva’s sentence was 10 years imprisonment but due to pressure from all over the world, she was released after 4 years and arrived in Israel.
After four years in the gulag and a worldwide campaign on her behalf, Sylva was freed. Arriving in Israel in 1974, she fought for the release of her two brothers, her husband – whose death sentence was commuted to 15 years hard labor – and other Prisoners of Zion, raising the cause with world leaders and holding a 16-day hunger strike at the United Nations. Eventually her pressure, and that of numerous other activists and world leaders, bore fruit, and most of the defendants were released before the end of their terms. In 1979, after nine years apart, Zalmanson and Kuznetsov reunited in Israel; a year later the couple had a daughter, Anat, who is now a filmmaker. For years, until her retirement in 2005, Sylva worked as a Mechanical Engineer. She is also a painter, starting in 1992. Working in acrylics and oil, her subjects are often depicted in vibrant colors, in mixed media. She exhibited in Israel, USA, UK, Italy, Romania and Finland, and was an accepted member of the "Painters and Sculptors Association of Israel".