{"id":3859,"date":"2025-10-14T12:40:18","date_gmt":"2025-10-14T12:40:18","guid":{"rendered":"https:\/\/www.newsbeep.com\/us-ca\/3859\/"},"modified":"2025-10-14T12:40:18","modified_gmt":"2025-10-14T12:40:18","slug":"how-did-a-disease-from-the-14th-century-reappear-in-northern-california","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us-ca\/3859\/","title":{"rendered":"How did a disease from the 14th century reappear in Northern California?"},"content":{"rendered":"\n

The plague \u2014 aka the Black Death, aka the Great Pestilence \u2014 is rarely contracted today, yet it recently infected a South Lake Tahoe resident. But before you put on your 17th century \u201cair-purifying\u201d beaked mask<\/a>, let\u2019s find out from the experts why this disease is still around and how dangerous it is now. <\/p>\n

Most people associate the term \u201cplague\u201d with the massive and destructive event that killed 25 million Europeans in the Middle Ages, said professor John Swartzberg of UC Berkeley\u2019s School of Public Health. In the 14th century, the plague killed as much as 50%<\/a> of Europe\u2019s population. <\/p>\n

\u201cThe plague is really a specific disease that has … in our human history [reared] its ugly head and caused massive deaths,\u201d said Swartzberg, who works in the university\u2019s Infectious Diseases and Vaccinology division.<\/p>\n

It may be a threat of the past, but it continues to be a very serious disease, with a small number of cases every year. <\/p>\n

In the recent case of the South Lake Tahoe resident, it\u2019s believed the person contracted the rare disease after being bitten by an infected flea<\/a> while camping in the area, according to El Dorado County health officials. <\/p>\n

The most recent case before this one was reported in El Dorado County in 2020 and also was believed to have been transmitted in the same area, officials said. Two plague cases were reported in California in 2015<\/a>, suspected to have been caused by bites from an infected flea or rodent in Yosemite National Park.<\/p>\n

Even though medical advancements have made the deadly disease treatable, it hasn\u2019t been eliminated.<\/p>\n

Contracting the plague, even today<\/p>\n

The plague is caused by the bacterium Yersinia pestis and primarily affects small animals or rodents in the United States, Swartzberg said. <\/p>\n

There are three types of the plague: <\/p>\n

bubonic plague, with the trademark swollen lymph nodes; septicemic plague, when the infection spreads throughout the body; pneumonic plague, which infects the lungs. <\/p>\n

It can spread to humans and pets from the bite of an infected flea or from coming into close contact with, or handling, an infected rodent. <\/p>\n

The plague was introduced to the U.S. in the early 20th century from rat-infested steamships arriving in California from Asia, with the first case identified in the San Francisco area, Swartzberg said. <\/p>\n

To date, the last known case of rat-associated plague occurred in Los Angeles in the 1920s, according to county public health officials. <\/p>\n

The principal source of plague in Los Angeles County today is wild rodents in rural areas. <\/p>\n

Most people who do contract the plague do so while hiking or camping in these areas, and are unknowingly bitten by an infected flea, said Ashok Chopra, professor of microbiology and immunology at the University of Texas Medical Branch.<\/p>\n

Animals live in much greater concentrations in rural areas, where they are in closer proximity to other creatures and habitats, making it easier for the bacterium to thrive, Swartzberg said.<\/p>\n

Woodland creatures that could carry the disease and should be avoided include chipmunks, wood rats, mice and marmots. <\/p>\n

Where the plague could be contracted in SoCal<\/p>\n

In California, public health officials say the plague occurs in the foothills, plateaus, mountains and along the coast. It\u2019s largely absent from the southeastern desert region and the Central Valley. <\/p>\n

There is the potential for exposure throughout Los Angeles County, but areas where the risk is highest are the rural recreational and wilderness areas of the Angeles National Forest and San Gabriel Mountains, county officials said.<\/p>\n

People and their pets can get the plague if they visit or live in areas where wild rodents are naturally infected, according to the Los Angeles County Public Health Department<\/a>. People who live in close contact with rats also are at greater risk of getting the disease from the possibly infected rodents.<\/p>\n

It isn\u2019t uncommon for dogs and cats to become infected because pets do get fleas. An infected flea, although rare, can sicken pets, which are vulnerable to the disease, Chopra said.<\/p>\n

Why the plague has stuck around<\/p>\n

The U.S. has eradicated only one human infectious disease, which is smallpox, and that was done through vaccination, according to the Centers for Disease Control and Prevention<\/a>. <\/p>\n

There have been several vaccine candidates to ward off the plague, but at this time there aren\u2019t any Food and Drug Administration-approved inoculations for the disease, Chopra said. <\/p>\n

\u201cWe don\u2019t know how to eradicate an infection in a mammalian population that\u2019s spread by a vector like fleas,\u201d Swartzberg said, \u201cso I don\u2019t see us being able to eradicate this at this time in our history.\u201d<\/p>\n

But the plague isn\u2019t a top priority for infectious-disease experts or public health officials because it\u2019s under control. <\/p>\n

\u201cElimination means the infection is gone in a geographic area and there\u2019s no localized transmission,\u201d Swartzberg added, \u201cso we\u2019ve pretty much eliminated the plague as a serious problem.\u201d<\/p>\n

So, how much should we worry? If we get treatment in a timely manner, there\u2019s little to fear, according to experts.<\/p>\n

The plague can be treated with antibiotics, Chopra said, but if left untreated it can be fatal.<\/p>\n

\u201cIf the infection is overwhelming,\u201d he said, \u201cthen the bacteria can spread fairly quickly into the bloodstream, and then it becomes very dangerous.\u201d<\/p>\n

Times staff writer Clara Harter contributed to this report.<\/p>\n","protected":false},"excerpt":{"rendered":"The plague \u2014 aka the Black Death, aka the Great Pestilence \u2014 is rarely contracted today, yet it…\n","protected":false},"author":2,"featured_media":3860,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[599,4723,7,9,8,1436,4719,4717,4725,63,4722,4724,4716,4720,4721,4726,4718],"class_list":["post-3859","post","type-post","status-publish","format-standard","has-post-thumbnail","category-california","tag-area","tag-ashok-chopra","tag-california","tag-california-headlines","tag-california-news","tag-case","tag-disease","tag-flea","tag-infection","tag-los-angeles-times","tag-most-people","tag-pet","tag-plague","tag-public-health","tag-rodent","tag-small-animal","tag-swartzberg"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/3859","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/comments?post=3859"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/3859\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media\/3860"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media?parent=3859"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/categories?post=3859"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/tags?post=3859"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}