A recent case of a cat infected with plague resulting in death was confirmed in Albany County, Wyoming, USA, reminding people that plague is not a distant “history,” but a disease still present in nature that requires vigilance and appropriate prevention. Although human cases of plague infection are uncommon, it is crucial to understand the transmission routes, symptoms, and preventive measures.

What is Plague?

Plague is a severe infectious disease caused by the bacterium Yersinia pestis. This bacterium is typically transmitted among small mammals and their fleas. Historically, plague caused pandemics resulting in millions of deaths, such as the 14th century "Black Death." Fortunately, plague can now be effectively treated with antibiotics.

Plague Situation in Cats in Albany County, Wyoming

According to the Wyoming Department of Health (WDH) notice, recent laboratory testing confirmed a cat died from plague infection in a rural area of Albany County, Wyoming. This cat primarily roamed outdoors or in outbuildings. In the past few months, several other cats at the same location have also died, indicating that plague may be spreading in the area. No human plague cases have been reported in this region yet, but the Wyoming Department of Health noted that last September there was a human pneumonic plague case in Fremont County linked to contact with a sick outdoor pet cat.

How is Plague Transmitted?

Plague mainly spreads among rodents (such as rats, ground squirrels, etc.). These animals and the fleas on them are the primary hosts and vectors for Yersinia pestis. Human infection usually occurs through several routes:

• Flea bites: This is the most common transmission method. Fleas that bite infected animals then bite humans, transmitting the bacteria.
• Contact with infected animals: Handling, skinning, or consuming infected animals (such as ground squirrels, rats, wild rabbits, feral cats, wild foxes, etc.) can lead to infection if the skin has breaks. Cats that prey on infected rodents or are bitten by fleas may also become infected.
• Respiratory transmission: Patients with pneumonic plague can spread infectious droplets through coughing or sneezing. Others may contract the disease by inhaling these droplets. Pneumonic plague is highly contagious and can cause human epidemics.

It should be noted that although cats can transmit plague to humans, this is relatively rare. In February this year, Oregon reported a confirmed human plague case caused by infection from a pet cat.

What Are the Symptoms of Plague Infection?

After infection, humans usually develop symptoms within 1-7 days of incubation. Plague has several types with differing symptoms:

• Bubonic plague: The most common type, usually caused by infected flea bites. The bacteria enter the lymphatic system and multiply in nearby lymph nodes, causing inflammation, swelling, and pain called “bubo.” Swollen nodes may feel soft yet firm and be about the size of an egg. Other symptoms include sudden fever (often 39-41°C), chills, headache, fatigue, muscle aches, nausea, and vomiting.
• Pneumonic plague: The most severe and rapidly progressing type. It usually develops after bubonic plague spreads to the lungs but can also result directly from inhaling infectious droplets. Symptoms may appear within 24 hours after infection, including high fever, chills, chest pain, breathing difficulty, cough, and possibly bloody frothy sputum. Without timely treatment, pneumonic plague progresses quickly within two days, potentially causing respiratory failure, shock, and death.
• Septicemic plague: This type results from bacteria entering the bloodstream and spreading throughout the body. Symptoms include high fever, chills, extreme weakness, abdominal pain, vomiting, diarrhea, bleeding tendencies (under the skin, mouth, nose), and gangrene leading to blackened extremities (toes, fingers, nose) and tissue necrosis.

How to Prevent Plague?

Although plague sounds frightening, it is preventable, controllable, and treatable. The key to prevention is cutting off transmission routes:

• Avoid contact with wild animals: Especially in known plague areas, avoid contact, hunting, skinning, or carrying ground squirrels, rats, wild rabbits, feral cats, and their products. Do not sit or rest near rodent or ground squirrel burrows.
• Prevent flea bites: When in environments possibly exposing to fleas (camping, hiking, outdoor work), wear long pants and sleeves to minimize skin exposure and apply insect repellents containing DEET on skin and clothing to prevent flea bites.
• Manage pets properly: Especially outdoor cats and dogs should be treated with flea control products. Avoid allowing pets to contact dead or sick rodents. If plague infection is suspected in pets, wear gloves and masks when handling and promptly seek veterinary care.
• Maintain good personal hygiene: Wash hands frequently and avoid crowded, unsanitary places.
• Report and seek medical care promptly: If fever, chills, swollen lymph nodes, cough, or coughing blood occur within 10 days after activities in plague-endemic areas, seek medical care immediately and inform the doctor about travel and animal contact histories. Report dead animals or suspected plague patients to local CDC promptly.

Plague Treatment

If plague infection is suspected or confirmed, immediate treatment is necessary. Plague is a bacterial infection effectively treated with antibiotics. Early diagnosis and treatment significantly reduce mortality. Common antibiotics include streptomycin, gentamicin, doxycycline, and ciprofloxacin. Doctors may start empirical antibiotic treatment based on symptoms and exposure history before confirmation.

Frequently Asked Questions

• Is plague transmissible between people? Yes, pneumonic plague can spread through respiratory droplets between people.
• Can pet cats transmit plague to me? Possibly, but rare. Cats may become infected by preying on infected rodents or flea bites, then transmit plague to humans through scratches, bites, or respiratory droplets.
• Does every flea bite cause plague? No. Only fleas carrying Yersinia pestis can transmit the disease.
• Is plague curable? Yes. With timely diagnosis and appropriate antibiotic treatment, plague can be cured.

Overall, although there are confirmed cat plague cases in Albany County, Wyoming, this reminds us that plague has not entirely disappeared. However, there is no need for excessive panic. Understanding plague transmission and prevention, taking proper personal protection—especially being alert in areas with wild animal activity—can effectively reduce infection risk. If suspected symptoms appear, timely medical care and informing doctors of relevant histories ensure prompt and effective treatment.