Dogs spreading Fleas, Worms, and other Illnesses

I. Early Accounts of Dogs Spreading Fleas & Worms by Sarah Smith

In the 18th and 19th centuries, dogs were frequently regarded with revulsion and feared as a health threat. Today, dogs are undoubtedly socially valued. This change in perspective started in the mid 19th century. By examining how dogs affected human health over the course of time, we can observe how they went from pests to pets.

Animals were just as much a daily part of urban life in Victorian cities as they were in the country. As industrialization progressed, so did the usefulness of many animals. Domestication of animals catalyzed the sentimentality in British populations and gave rise to sympathetic organizations such as the Royal Society for the Prevention of Cruelty to Animals. However, without understanding the consequences, domestication of animals cans be dangerous to humans. Earlier in the 19th century, people did not realize the connection between animals and human health. Even when the Public Health Act of 1872 was passed, human carelessness was the main focus:

“Yet if urban public health departments were preoccupied in sorting out the consequences of man’s own activities, there were other factors which contributed to a disregard for potential associations between human and animal disease,” (Hardy 2010).

Even before the modern sciences of parasitology and bacteriology, people viewed dogs negatively because their apparent uncleanliness brought mysterious illness. Dogs were not kept as pets; they were working animals. In the 19th century, many Medical Officers of Health carried out experiments to make baseline conclusions about the correlation between dogs carrying insects and uncleanliness. Then, they further correlated uncleanliness with illness in humans. “Rubbish, dust, maggot infested dead dogs, and offensive gullies infect marine shore parishes,” according to the MOH for Hanover Square in 1866. Another MOH explained an experiment conducted to determine why there was an increase in exposure to dog carcasses, which causes human illness. “Dogs were exposed to the influence of sewer gas, all of which got sick and died… ventilating shafts are left open for hours by workmen… cases of extreme dangerous illness from this cause,” (Bermondsey 1858). The need of precautionary action for health risks was presented in many of these reports. It was also understood that dead dogs were not the only source of human illness. “Worms found in excrement are tracked home on boots and contribute to human disease,” wrote the MOH for Islington in 1861. Dog feces were pretty well known to correlate with sickness by containing parasitic organisms, which is why ‘fouling the foot paths’ was considered such a nuisance. The progression of awareness spread to the understanding that these pathogens could be transferred through different forms of contact. “Evening scraps left from family’s dinner attracts pests and threatens health of inhabitants,” stated the MOH for the City of London in 1864.

The next implementation of public health practice was to make strategies of prevention general public knowledge and put the responsibility of taking appropriate precautions into the hands of each individual. With Europe being predominantly Christian, many people believed in the complete distinction between humans and beasts. “It was not until the new bacteriology began to uncover the specific agents of disease after 1876, that evidence began to emerge, effectively establishing links between animal and human diseases” (Hardy 2010). With this evidence, people started believing in the danger associated with careless handling of animals. To swiftly start an effective movement across the public, the state had to appeal to the social values of the population. Peter Atkins explained in his book Animal Cities, “One way to achieve the mass persuasion towards the goal of sanitation was to find moral naturalism and spiritual satisfaction in the outcomes, often portraying dirty environments as bad and their inhabitants as dangerous” (Atkins, 27). With this intention, most of the Medical Officer of Health reports were aimed toward suggestions of sanitation based on evidence of reported cases. “Children have picked up worms in larval stages when coming in too close contact with dogs, such as face licking… it is advised to keep all contact away  bodily fluids,” (Barking 1896). Another reported situation of contraction from contact was, “Owners of sick dogs should be warned not to handle excreta and to take great care to avoid contact with the dog’s urine. The infection may also be contracted from bathing in pools contaminated by the urine of dogs carrying or suffering,” (South Hornsey 1894). By reporting these incidents, public awareness was brought to danger situations of contact from pathogens. For livestock owners, precautions were encouraged when dealing with sick dogs and the rest of their animals. “Cattle of which have been bitten by a mad dog, or any other mad animal, as well as the flesh of measly pigs, must not, on any account, be exposed for sale,” (City of London 1897). At this point the public did not have much individual prior knowledge, but were advised of situations to be wary of.

As time passed, awareness of sanitation became a requirement as regulations started to be more strictly enforced. This expanded the responsibility of prevention from just individuals to a public health standard for society as a whole. With sanitation being a pretty established value, more people felt free to take dogs into their homes. “As London grew, sanitation regulations were imposed. As other animals disappeared from the streets, the pet dog filled a vacuum and were invited in from the cold” (Howell 2015). The Medical Officer of Health Reports started to look more and more like documented charts of regulation breeches or accidental exposures. “Fleas from a stray dog bit woman causing disease and eventual death. The dog was taken and washed with a solution of electrolytic fluid. There were several contacts in this case who were kept under observation, and vaccination,” (Poplar 1911). Because reports of infection and death were becoming less common, more careful detail over cases could be kept for research. MOH report, “Regulations requiring the wearing of collars by dogs while on a highway. Under these regulations, 11,611 dogs were seized by the police during 1920 and 7,244 destroyed,” (London County Council 1920) and “Dogs with viral infection are kept strictly isolated from all other dogs during the six months period of quarantine,” (Hendon 1962) both reported affirmative action being taken in these threatening situations. The public health system at this time has become more controlled by regulation and growth in scientific discovery. Much of this situation changes throughout the history of the 20th century that affects the relationship between poverty, disease and the state. Jordon Larsen, co-author of this page, will go on to explain this part of medical history.


V0019964 Toilet of a Spanish Family; flea picking
A man, boy, girl, woman, and baby picking fleas from each other’s heads with a dog seated next to them.  Credit: Wellcome Library, London.

II. Later Accounts Linking Dogs with Pests by Jordan Larsen

As noted above, London’s Medical Officers of Health linked dogs to disease by the 19th century, but these associations and interventions expanded in the 20th Century.  They began to increasingly “make a connection between the health and welfare of animals and the welfare of the state, or between the health and welfare of animals and that of the humans who depended on them for food, labor, and companionship” (Hardy, 374).   While rabies may have been the most common disease associated with dogs, London’s public health records indicate that the transmission of pests like fleas and worms and other diseases was also a common and anxiety-provoking problem for 20th-century Londoners.  The three main methods of this transmission appear to be through dog waste, proximity to dogs in the household or on the streets, and consumption of food contaminated by dogs allowed in shops or restaurants.

London’s health reports and historians make clear that dogs were ubiquitous in Victorian England, whether in the home as pets or wandering the streets as strays.  As evidence of the second instance, London’s Battersea Home for Lost and Starving Dogs received over “150,000 dogs during the first seventeen years of its operation” (Ritvo, 170).  Where there are dogs there is also dog waste.  The London Medical Officer of Health Reports include countless notices calling for the removal of dog excrement from public pavements.  The British took dog excrement to be more than just a nuisance; they believed that “decomposing organic matter released vapors that generated acute diseases and general ill-health in humans” (Hardy, 374).  More specifically, one health report reveals that by this period, it was common knowledge that dogs excrete germs capable of making humans ill. A later report from Hammersmith in 1962 notes that disease may be transmitted through water contaminated with the urine of infected animals. The health officer reported that a city drainage worker died from Weil’s Disease, and the source was traced back to infected animals nearby.  However, officials reportedly struggled to find an adequate remedy for keeping London streets clean. Owners of sick dogs were “warned not to handle excreta and take great care to avoid contact with the dog’s urine” and to avoid swimming in contaminated, non-chlorinated water in a 1954 report from Hornsey. One historian characterizes this struggle as the medical community “prioritizing public health over the interest of private individuals,” enforcing strict rules posted in public notices and regulating dog ownership with fees (Howell, 229).  These regulations did receive resistance from the dog-owning community, which is perhaps also evident in the multitude of notices spanning decades in the public health records.

The next transmission method linking dogs with pests and disease is general proximity in the houses and streets.  The Victorian Period brought an increase of dog ownership, and some of these dog owners voiced concerns over the cleanliness of their dogs.  In a 1948 Barking borough report, one dog owner wrote her public health officer asking if the vermin commonly found on her pet dog and cat were a danger to her children.  The officer responded in the negative, explaining that “fleas from dogs and cats fortunately do not trouble human beings.”  He conceded that worms “may be picked up from too intimate contact with dogs,” but that this is not as likely in urban Barking as in the country.  However, the officer finished with a warning that “it is never wise to let your child kiss her dog’s nose.”  In contrast, the 1920 Bermondsey report cites that occasionally the ctenocephalus canis, or dog flea, was found on humans, and that a flea epidemic coincided with a scarlet fever epidemic, though no direct relationship was expounded.  Another report from Acton in 1904 notes an official “amused” by a woman who called his office to request that a neighbor’s “mangy” dog be destroyed because it had transmitted an unnamed disease to seven local children.  These interactions demonstrate that 20th-century British public health officials combated their public’s concerns and misconceptions about dogs’ effects on health. Medical officers of health kept track of the number of people bitten by dogs, evidence that they linked dogs to the health and safety of the people.  Even if dogs were understood not to transmit one certain pest or specific disease, people often considered them unclean and a potential health threat.

V0010807 Advert for soap featuring little girls and dogs
Upper: A girl washing a dog as an advertisement for Nubolic soap. Lower: A girl talking to her dog about the dirty marks he has left on her pots and pans, to be cleaned with Sparkla soap.  Credit: Wellcome Library, London.

The final method through which dogs might transmit pests and disease is food contamination.  One medical officer of health reported a meat shipment that contained livers full of echinococcus cysts, the dog tapeworm in an early stage of its life cycle; one man died from eating this liver.  Reports from Wimbledon and Stoke Newington in the 1950s reference clean food campaigns and specifically highlight notices requesting that customers not bring dogs into food shops. These “printed notices were issued to all food traders in the Borough for exhibition on their premises,” requesting public cooperation to reduce food contamination by dogs.  These instances speak to one historian’s claim that Victorian British morality asserted that “the demands of humanity as well as of hygiene and public order require [dogs’] removal to domestic spaces where they can be enclosed and disciplined” (Howell, 226).

Part I Sources:

  1. Islington 1861
  2. Bermondsey 1858
  3. Barking 1948
  4. Hanover Square 1866
  5. Croydon 1945
  6. City of London 1922
  7. City of London 1970
  8. City of London 1864
  9. Hammersmith 1924
  10. London County Council 1920
  11. Hendon 1962
  12. Poplar 1911
  13. Hornsey 1954
  14. Howell, Phillip. “How the Dog Found a Place in the Family Home – From the Victorian Age to Ours.” The Domestic Dog in Victorian London , May 15, 2015. Accessed April 4, 2017. University of Cambridge.
  15. Hardy, Anne. “Pioneers in the Victorian Provinces: Veterinarians, Public Health, and Urban Animal Economy.” 1AD ed. Vol. NW1. Euston House, London: Wellcome Trust Centre for the History of Medicine at UCL, 2010.
  16. Peter Atkins, ed., Animal Cities: Beastly Urban Histories (2012)

Part II Sources:

  1. Acton 1904London’s Pulse: Medical Officer of Health reports 1848-1972.
  2. Barking 1948London’s Pulse: Medical Officer of Health reports 1848-1972.
  3. Bermondsey 1920, London’s Pulse: Medical Officer of Health reports 1848-1972.
  4. City of London, 1961London’s Pulse: Medical Officer of Health reports 1848-1972.
  5. Croydon 1945London’s Pulse: Medical Officer of Health reports 1848-1972.
  6. Hammersmith 1962London’s Pulse: Medical Officer of Health reports 1848-1972.
  7. Hardy, Anne. “Pioneers in the Victorian Provinces: Veterinarians, Public Health, and Urban Animal Economy. ” Urban History 29, no. 3 (2002): 372-387.
  8. Hornsey 1954, London’s Pulse: Medical Officer of Health reports 1848-1972.
  9. Howell, Philip. “Between the Muzzle and the Leash: Dog-walking, Discipline, and the Modern City.” In Animal Cities: Beastly Urban Histories, edited by Peter Atkins, 221-241. Surrey, UK: Ashgate Publishing Limited, 2012.
  10. Kensington 1954London’s Pulse: Medical Officer of Health reports 1848-1972.
  11. Ritvo, Harriet. The Animal Estate: The English and Other Creatures in the Victorian Age. Cambridge, Mass. : Harvard University Press, 1987.
  12. Stoke Newington 1952, London’s Pulse: Medical Officer of Health reports 1848-1972.
  13. Wimbledon 1951London’s Pulse: Medical Officer of Health reports 1848-1972.