The Mott Clinic

The Horton Malaria Laboratory (1925-1975)


The following topic is broadly based on an article by Henry R Rollin - "The Horton Malaria Laboratory, Epsom Surrey (1925-1975)" Published in the Journal of Medical Biography 1994: 2: 94-97

Woman Suffering From General Paralysis of the Insane
Woman Suffering From General Paralysis of the Insane c1869
Photgragh taken in West Riding Lunatic Asylum, Wakefield, Yorkshire.
Image source: Wellcome Images (WI no. L0019063)

In Austria in 1917 Julius Wagner-Jauregg, a professor of psychiatry at the University of Vienna, reported dramatic success in treating patients with the previously incurable condition of General Paralysis of the Insane (GPI). He got a Nobel Prize for his work in 1927.

The cause of GPI - spirochaete Treponema pallidum
The cause of GPI - spirochaete Treponema pallidum

Patients with this illness would initially show signs of sudden and often dramatic psychotic symptoms, have unusual eye and muscular reflexes, have speech and hearing problems, develop seizures and dementia. Eventually they became completely incapacitated and, over a course of three to five years, would die. The cause of GPI was known to be bacteriological - a syphilitic invasion of the central nervous system by the spirochaete Treponema pallidum bacterium. The new treatment involved deliberately infecting GPI patients with a separate and potentially lethal disease - malaria!

Wagner-Jauregg was aware that remissions and even cures had been reported in patients who had also contracted other illnesses, such as typhoid, resulting in high temperatures. His idea was to induce a high fever and so raise their body temperature and kill off the bacteria in the brain. (During a malaria attack the patient's temperature often rose to 40ºC or higher.)

A Mosquito
A Mosquito

In July 1917 he inocculated nine GPI patients with blood from a malarial patient. He reported complete recovery in four of these patients and considerable improvement in two more. He then devised a complex treatment protocol, first testing the blood of 275 "at risk" patients. He then treated them with malarial blood, followed by quinine (to quench malaria), alternating with injections of neosalvarsan to clear the blood of spirochetes. His success rate was remarkable: 83 % of the patients were free from the progression of the illness. He proved that successful malaria inoculation therapy would stop the progress of GPI and reverse some symptoms but this treatment could not reverse any long term damage already caused. However, if treated early enough patients, would make a good recovery and could often return home and even resume work.

The news of these experiments was of great interest to those involved with mental health as it was the first real treatment that could be used on GPI sufferers who amounted to about 1 in 12 of mental hospital admissions. The experimenters faced several moral, legal and ethical dilemmas as they would not normally knowingly infect a patient, with a potentially lethal disease, let alone one that would require significant additional nursing care.

The First World War delayed the introduction of this treatment into the UK, until Professor Warrington Yorke experimented with it at Whittingham Mental Hospital near Liverpool. On 21 July 1922 he inoculated three male patients with blood from a malaria patient. In the same year Lieutenant-Colonel Sydney Price James (1870-1946) of the Indian Medical Service experimented with malaria therapy at the Manor War Hospital in Epsom. The following year some of the mental hospitals run by the London County Council (LCC), including Horton, started trials the malaria therapy. As there was a risk of other patients contracting malaria, in 1925 it was decided to set up a specialist centre for London just to provide this malaria therapy for GPI patients. The centre, together with a separate specialist laboratory just to study malaria, was established in the isolation building at Horton Hospital, Epsom.

The first Director of the specialist malaria laboratory at Horton was Lieutenant-Colonel James. He worked out a set of criteria to be met before a particular strain of the malaria parasite should be used for malaria therapy. On 25 May 1925 infected mosquitoes, that met this criteria, were allowed to feed on two female patients at the Horton Centre and the so called Madagascar strain Plasmodium vivax of malaria was recognized. The discovery of this strain together with many others helped to establish the worldwide reputation of the laboratory.

Malaria parasites destroy red blood cells
Malaria parasites destroy red blood cells

At this time Horton Hospital had mainly women patients but soon men were admitted to the unit which was initially known as 'C' Hospital. Early trials had many failures,some fatal, as the clinicians needed to experiment with different combinations of drugs to have the best effect on the GPI infection and minimise the unwanted effects of the malaria. By 1935 about 700 patients had been treated, of which 75% were said to have recovered completely. Towards the end of its use the full recovery rates for malaria therapy were in the region of 30 to 35 percent with many more patients having the progress of their illness paused or halted. Whilst this level of full recovery may seem low today the results were better than nothing and the treatment helped many thousands of people who previously had no hope.

The name of the centre, 'C' Hospital, changed to the Mott Clinic in the late 1920s, named after the Director of the Central Laboratory and Pathologist to the LCC Mental Hospitals, Sir Fredric Mott (1855-1926).

The Mott Clinic
The Mott Clinic

During the Second World War supplies of quinine were greatly reduced. This caused concerns for the Allies fighting in Africa and the Far East as this debilitating disease could put large numbers of troops out of action. A promising anti-malaria drug, Mepacrine, was successfully tested at the Horton laboratory under wartime maximum security conditions.

Many of the directors of the laboratory became distinguished because of their work. These include John Alexander Sinton VC FRS (1884-1956), Major General Sir Gordon Covell (1877-1975) and Professor P C C Garnham (1901-1995). Of particular note is P G Shute OBE (1894-1977) who was injured in WWI and repatriated to Manor War Hospital.While convalescing, he worked at the laboratory for Colonel Sir Ronald Ross Nobel Laureate (1857-1932). Shute, though poorly educated, was soon found to have great skill in examining blood for malaria parasites and in dissecting mosquitoes. He went on to become a major player in the field of malaria research, by increasing the knowledge of the parasite's life cycle. Shute was ably assisted by Marjorie Maryson.

Sir Fredrick Mott Prof Warrington Yorke
Sir Gordon Covell Professor Percy Cyril Claude Garnham
John Alexander Sinton Percy G Shute
Sir Ronald Ross
(Top Row L to R) Sir Fredrick Mott and Prof Warrington Yorke
(Row 2 L to R) Sir Gordon Covell and Professor Percy Cyril Claude Garnham
(Row 3 L to R) John Alexander Sinton and Percy G Shute
(Row 4) Sir Ronald Ross
Image source: Wellcome Images

Today GPI is rare thanks to antibiotics such as penicillin which came in shortly after the end of World War Two. The introduction of penicillin greatly reduced the demand of malaria therapy. The laboratory was turned into a malaria research centre called the Horton Malaria Reference Laboratory which became the WHO Regional Malarial Centre of Europe. In 1973 the laboratory and what remained of the Mott Clinic were closed and work transferred elsewhere. During its existence the centre treated approimately 10,000 patients and the laboratory provided material for inoculating patients in other parts of the UK and Europe. The centre also trained clinical and laboratory staff for many other hopsitals. Records of the Mott Clinic are at the London School of Hygiene and Tropical Medicine and some other items are held by The Wellcome Library. A plaque to the Mott Clinic and to those who worked there was unveiled at the building on 25 June 1975 by Professor P C C Garnham FRS. The plaque is now at Bourne Hall Museum, accession no. 2006.100.

The mosquito breeders

The patient is taken into a special room having double doors and windows. The room contains no crevice in which an infected mosquito could be lost. An expert releases the mosquitoes one by one from a special box. After the patient has been inoculated the mosquitoes are caught - a task involving much patience - and counted back into the receptacle.

The patient, after the usual period of incubation, develops malarial fever, for which he is treated in the ordinary way. It is claimed that men and women who otherwise would have died insane have been restored mentally, and some are able to follow their occupations.

The treatment was discovered accidentally. A short time ago malaria broke out in a mental hospital in Southern Europe. When the fever passed it was found that the general paralysis of the insane sufferers had regained their sanity.'

Westminster Gazette, 13 August 1925


This article was researched and written by Peter Reed, 2006