Printer-friendly versionPrinter-friendly version Share this


East County News Service

September 23, 2014 (Palomar) -- County officials are reminding people to protect themselves when they hike and camp after two squirrels trapped in routine monitoring in the Palomar Mountain area tested positive for plague.

Plague caused the death of millions during the Middle Ages, but today can be treated with antibiotics.  Without treatment, however, the disease can still cause serious illness or death, so avoiding contact with infected rodents or fleas that also transmit the disease is the best prevention.

County officials said the two squirrels were trapped last week in the Doane Valley Campground area and that people can protect themselves and pets by remembering some simple rules.

“People need to remember not to feed or play with squirrels when you come across them outdoors,” said San Diego County Environmental Health Director Liz Pozzebon. “Don’t play near squirrel burrows or set up your tents around them, and report dead squirrels to camp rangers.”

Environmental Health Vector Control crews have posted warning signs and dusted squirrel burrows in the area to kill the fleas that can transmit plague from squirrels and rodents to people.

It is not uncommon to find the bacteria — Yersinia pestis — that causes plague in San Diego County’s higher elevations, County officials said. The disease mainly affects wild rodents. However, it can be spread to humans when fleas first feed on infected animals and then bite people, or when people such as hunters handle the tissue or body fluids of infected animals.

People who contract plague can become seriously ill, and even die, unless they are treated quickly with antibiotics. Symptoms include sudden onset of fever, chills and tender lymph nodes.

County officials said hikers and campers in rural mountain areas should look for plague warning signs and always follow simple steps to make sure they don’t come into contact with disease-carrying fleas:

  • Avoid contact with ground squirrels, chipmunks and other wild animals.
  • Do not feed, touch or handle wild animals. Do not rest, camp or sleep near animal burrows in the ground.
  • Do not touch sick or dead animals.
  • Protect your pets by keeping them on a leash, by using flea controls, or even better, by leaving them safe at home.
  • Contact your doctor immediately if you become sick within a week of visiting an area known to have plague.

According to the CDC, the disease can also be transmitted to hunters handling an infected carcass.  The disease can also be transmitted to predator animals or cats if they consume an infected rodent. 

The plague can take several forms: bubonic, septicemic or pneumonic. According to the Centers for Disease Control:

Bubonic plague: Patients develop sudden onset of fever, headache, chills, and weakness and one or more swollen, tender and painful lymph nodes (called buboes). This form usually results from the bite of an infected flea. The bacteria multiply in the lymph node closest to where the bacteria entered the human body. If the patient is not treated with the appropriate antibiotics, the bacteria can spread to other parts of the body.

Septicemic plague: Patients develop fever, chills, extreme weakness, abdominal pain, shock, and possibly bleeding into the skin and other organs. Skin and other tissues may turn black and die, especially on fingers, toes, and the nose. Septicemic plague can occur as the first symptom of plague, or may develop from untreated bubonic plague. This form results from bites of infected fleas or from handling an infected animal.

Pneumonic plague: Patients develop fever, headache, weakness, and a rapidly developing pneumonia with shortness of breath, chest pain, cough, and sometimes bloody or watery mucous. Pneumonic plague may develop from inhaling infectious droplets or may develop from untreated bubonic or septicemic plague after the bacteria spread to the lungs. The pneumonia may cause respiratory failure and shock. Pneumonic plague is the most serious form of the disease and is the only form of plague that can be spread from person to person (by infectious droplets).

Plague is a serious illness. If you are experiencing symptoms like those listed here, seek immediate medical attention. Prompt treatment with the correct medications is critical to prevent complications or death.

For more information about plague surveillance, call the County Vector Control Program at (858) 694-2888 or visit the Vector Control Program website