The Isolation Hospital was three miles south of Alnwick, and intended for treatment of Smallpox. It was jointly operated by Alnwick Urban and Rural District Councils, Amble, Belford and Rothbury.
The World Health Organisation declared that Smallpox had been eradicated in 1980. Before that, there were two forms of the virus. Variola major was the more severe, with a death rate of about 30%. Variola minor was less severe, with death rates below 1%. In the UK the last significant outbreak of Variola Major was early in the 20th century. The last major outbreak of Variola Minor began around 1919, and peaked in the late 1920s.
At the start of the 20th century Medical Officers periodically had to deal with small outbreaks of smallpox brought from overseas, and ports such as Blyth made provision to isolate patients. However, there would sometimes be a more serious outbreak, and most districts in Northumberland had made no preparations to isolate smallpox patients. This was causing some concern, but provision would only be made after a more serious outbreak reached Northumberland. Then 409 cases were reported in 1903 and 373 in 1904. By 1905 a site had been identified for Alnwick and plans prepared. The Alnwick Engineering and Foundry Company tendered to provide a corrugated iron building at £264. The chosen site was alongside the former Shilbottle Wagonway.
The Isolation hospital had been opened by 1909, but as things turned out there would not be another serious outbreak of smallpox in Northumberland for almost two decades, and the hospital normally seems to have been moth-balled. In 1911, though, it was opened and used to treat victims of an outbreak of Enteric Fever (typhoid) at Hipsburn.
Then in the 1920s the number of small-pox cases in Northumberland started to rise again. In 1924 the county reported 392 cases and in 1925 it reported 629. Ashington, Bedlington, and Prudhoe were badly affected, and the Medical Officer was clearly disappointed that the response in Ashington fell short of what was needed. Smallpox was prevalent in Morpeth, but only one case fell within the Alnwick district. To open and staff the Alnwick isolation hospital for one person would be expensive, so a 75-year old patient from the Alnwick District was treated in the Morpeth Smallpox Isolation hospital at Chevington. He recovered, and the number of cases fell away again.
Early in WW-2, when children were first evacuated from the cities there were concerns in rural areas that children from slum areas would spread infectious diseases. By 1939 there had been no cases of smallpox in the county for several years, so the Regional Medical Officer decided that the hospital would better be used to isolate evacuated children suffering from contagious diseases such as scabies, impetigo and ringworm. A year later the Medical Officer reported that the isolation hopital had been almost continuously in use for this purpose: normally treating from 5-15 patients. Similar diseases were not unknown in rural areas but the Alnwick Isolation Hospital was only used to treat evacuees – it was not used to treat local children.
After the war the Ministry of Health assessed all the Northumberland hospitals and in 1947 it found the Alnwick Isolation Hospital was unfit for treatment of the sick, and they declared that it should be closed. The buildings continued to appear on OS maps that were surveyed in the early 1950s, but by then they are no longer marked as a hospital. The two wards and a separate accommodation building still remained, and a family lived there until it was demolished in 1967, or thereabouts. By then the corrugated iron was more than 60 years old, but still in good condition, and it was re-used for farm buildings. Nothing remains now.