[4] She later became a matron at Wellington Hospital,[5] New Zealand, having gone there with her mother Sarah, to nurse her own sister who was ill with tuberculosis.

In her final lecture she announced that she intended to visit Louis Pasteur in Europe, and then go on to work with Father Damien in Hawaii caring for lepers.

[6] She travelled from Tottenham to Bulgaria with others to nurse Russian soldiers wounded in Russia's war with Turkey in 1877.

Working at the Red Cross mission, her selflessness and devotion brought her an award from Empress Maria Fedorovna.

[7] Marsden would later report that she looked after lepers in New Zealand – but although there was a similar disease there was no leprosy amongst the Māori people.

[8] She continued to work as a nurse whilst also visiting the sick but wanting to leave for the British colonies to treat leprosy.

According to her book On sledge and horseback to the outcast Siberian Lepers, she met an English doctor in Constantinople who told her of the curative properties of an herb found in Siberia.

The Tsarina gave her a letter encouraging all who read it to assist Marsden with her plans to investigate leprosy in Siberia.

[12] In 1892, she became a fellow of the Royal Geographical Society[11] and she was personally given an angel shaped brooch by Queen Victoria.

[10] She never fully recovered from her journey but she gave her account of it in her book On Sledge and Horseback to Outcast Lepers in Siberia, published in 1893.

Although the Girl's Own Paper serialised her exploits and she was lauded by the Royal Geographical Society, accounts by William Thomas Stead held her accomplishments up for public derision.

The Reverend Alexander Francis, an English-speaking pastor in St Petersburg, obtained a confession from Marsden of "immorality with women".

[19] In 1893 Isabel Hapgood reviewed the book by Marsen describing her journey, and like others cast doubt on Marsden's efforts.

[23] In 1913 the Mayor of Bexhill contacted the committee and revealed that Marsden had been involved in controversy over funds and her sexuality.

[24] The Charity Organisation Society advised that Marsden was "not a fit person to manage charitable funds".

[24] The controversy surrounding Marsden was not resolved and she finished her life suffering from dropsy and senile decay.

The researchers found the buildings that had made up the leprosarium which today are used as a village hall and as a residence in the settlement of Sosnovka which formed part of the leper hospital.

[27] In 2009 a foundation stone was laid to mark Marsden's 150th anniversary for a planned memorial and park in Yakutia.

[13] The Royal Geographical Society has a small collection of items that belonged to Marsden including her watch, a whistle and the brooch that was given to her by Queen Victoria.