Trachoma: A Very Brief History

by John S. Emrich and Charles Richter
October 2023

Trachoma is an ancient disease of the eye that regularly caused blindness in a very visible way. Today, according to the National Eye Institute, NIH, it remains the leading cause of preventable blindness worldwide. A short time after initial infection, the patient may develop sensitivity to light, excessive tearing, and, most notably, inflammation and the resulting redness of the upper eyelid. This last symptom remains mild for many patients, while about a third will have a severe response that includes “pus-exuding, granular, beefy-red eyelids that conjure up one of the most familiar clinical descriptions of trachoma.” Hippocrates analogized eyelids of those in the acute phase to the lid to a cut ripe black fig—red, thickened, and speckled with white dots. He also first referred to the disease as “ophthalmia,” a name the disease would retain for many centuries. If left untreated, the patient will have scar tissue begin to form on the upper eyelid.

Following the acute phase, which can last for a few days to a few weeks, the patient enters cicatricial (scarring) trachoma, when inflammation may subside, but the scarring caused by the active phase begins the slow process of blindness by either causing the eyelid to buckle so the lashes rub, irritate, and eventually scar the cornea or the inflammation under the eyelids irritates the cornea and is compounded by the scratching of the in-turned eyelashes.

Origins

There is, however, some debate about its origins between the Yangtze and Yellow Rivers in China or the Tigris-Euphrates river system in Mesopotamia. Current evidence adds more weight that transmission between humans began at a time when the aggregation of early settlementscreated the crowded conditions that would have allowed the disease to flourish. As these areas sat at the crossroads of many ancient trade routes could have easily acted as the source of the spread the disease.

 

The historical record is clear that trachoma was endemic in other major river valley settlements of antiquity—Indus and Ganges (India), Nile (Egypt), in addition to the potential origin sites in China and Mesopotamia. Reference to trachoma in China date back to 2700 BCE, Sumer in 2000 BCE, Egypt in 1550 BCE, India between 1000 and 500 BCE, Arab authors in the ninth century BCE, and Ancient Greece, described by Hippocrates, Plato, and Aristotle. It was not until the Napoleon’s Egyptian campaign (1798–1801) that trachoma became a serious presence in Europe. During the campaign, trachoma was an epidemic among both the French and British troops. As there was no cure, civilian outbreaks soon followed with the return of the soldiers.

Medical Response

Following the outbreaks caused by the Egyptian campaign, European militaries took the disease seriously as it spread easily and diminished readiness. Many created separate eye hospitals for treatment and research into the cause of the disease. This was replicated in the civilian sphere with the creation of eye hospitals and clinics and a new field of medicine, ophthalmology, was created and quickly spread to hospitals.

In the United States

It is unknown when trachoma first arrived in the United States, though there is evidence that there were numerous cases in the early to mid-19th century. Hospitals specializing in eye or eye and ear started springing up in the 1850s, and the U.S. military began surveilling sailors and soldiers for trachoma around the same time.

Everything changed in 1897 when Walter Wyman, supervising surgeon general of the U.S. Marine Hospital Service (MHS), declared trachoma to be a "dangerous contagious disease" that was “seldom seen except among recent immigrants from the eastern end of the Mediterranean, Polish and Russian Jews, Armenians and others from that locality.” Wyman instructed his medical officers to examine the eyes of immigrants entering the United States, paying special attention to those with inflamed or watery eyes. As noted earlier, trachoma was widespread in most of the U.K. and Europe, so Wyman’s orders were clearly targeting the wave of immigrants from Southern and Eastern Europe (many of whom were Jewish) as well as from Asia.

As a response to the feared importation of trachoma from immigrants, U.S. Congress passed a 1902 law fining the steamship companies $100 per person who was diagnosed with trachoma and required the company to return the immigrant back home for treatment. In response, the companies began their own trachoma screening at the ports of entry and many potential immigrants were not able to board the steamships. In 1905, a new law required trachoma screening of every immigrant and barring entry to anyone who was diagnosed with the disease. If it was diagnosed as an easily curable case, the immigrant would be held and treated at the station. (The anti-immigrant fervor would reach a political crescendo less than two decades later with the passage of the Immigration Act of 1924, which created a quota for the number of immigrants from different regions of Europe that could enter the United States while excluding Asian immigrants.)

In 1912, the MHS began a three-year survey of trachoma in an area across the central United States, dubbed the “trachoma belt,” as well as at a number of Indian reservations. (The trachoma belt extending through Virginia, Kentucky, Tennessee, Missouri, Arkansas, Alabama, and Oklahoma, and included small parts of Ohio, Indiana, Illinois, and Kansas.) The results at the end of survey told a story of endemic trachoma in rural school children, factory workers in Youngstown, Ohio, and across many Indian reservations.

Although the causative agent for trachoma was still unknown, three commonalties in these populations wereidentified: crowding where one slept and bathed, inadequate hygiene, and poor sanitation. The alleviation of these conditions dovetailed nicely with the strengthening public health movement and related infrastructure projects in cities, including public running water, toilets, and trash removal. In the rural communities, where trachoma was sometimes referred to as a “family disease,” different solutions were needed.

As the MHS survey found, an example from the mountains Kentucky share commonalities with other rural areas of the trachoma belt: “The whole family often sleep, live, and cook in the one room of the home, and in addition, use the same towel for days without changing, and wash in the same basin, which is often a stone partially buried beside the well and having a deep depression on the top, the thorough cleaning or even emptying of this rudimentary basin being practically impossible.” The response by the MHS was to create trachoma hospitals, with the first was opening in Kentucky in 1913. In addition to Kentucky, hospitals were constructed in Virginia, West Virginia, Tennessee, North Dakota, Arkansas, Georgia, and Missouri.

The small trachoma hospitals acted as a hub where screenings, treatment, research, and education were undertaken. The early success of the hospitals led to the creation of smaller, outpatient trachoma clinics. Each clinic was headed by a nurse who traveled from the hospitals to remote areas to provide services, including better disease surveillance, and to bring back patients to the clinic or hospital for treatment.

Treatment

The basic treatments for trachoma did not change greatly from ancient times through the mid-19th century. It typically involved turning the eyelids inside out and then scraping the follicles. There were, of course, attempts at herbal and metal remedies as well as variations in surgical techniques, including some surgeons removing more of the eyelid, including tarsectomy (removal of the diseased tarsal plate and underlying conjunctival tissue), which denounced as a treatment by the wider medical community in the late-1920s. Sanitary conditions, pain management, and instruments were improved over the centuries, but the technic was still used into early twentieth century until the advent of sulfa drugs. These were used predominantly for outpatient treatments as well as following surgeries. The advent of antibiotics dramatically changed the treatment for trachoma, with surgery necessary only in the most extreme cases.

Finding the Causative Agent

The germ theory of disease, established in the 1870s, meant that there must be a causative agent for trachoma; it could no longer be caused by the mysterious and anomalous “miasma.” In 1907, Austrians Ludwig Halberstaedter and Stanislaus von Prowazek were able to demonstrate the transmissibility of the disease via scrapping from conjunctival secretions of infected orangutans to healthy orangutans. Their findings were successfully repeated by other researchers, but none could isolate the microorganism that cause trachoma. As no technique could isolate the microorganism as a bacterium, for decades it was believed to be a virus.

In 1957, T’ang Feifan, Chang (Zhang) Xiaolou, Huang Yuantong, and Wang Keqian at Tong Ren Hospital in Beijing successfully isolated the causative agent in a chick embryo. After many tests, the researchers realized that it was not a virus, but a strain of chlamydia—one of the few bacterium small enough to pass through the finest laboratory filters of the day. The successful culturing of the bacterium enabled the researchers to share their results with other labs around the world.