Goat Flu (Q Fever) Occurs in US Soldiers, Stateside
The recent epidemic of goat flu (Q fever) in the Netherlands that has resulted in more than 2,300 cases in humans and six deaths has not affected the United States, but goat flu is not unknown in America. Approximately 50 to 60 cases of the disease are reported in the United States each year, and since 2003, more than 30 cases have been reported in US soldiers serving in Iraq and Afghanistan.
Goat flu, often commonly referred to as Q fever (“Q” for “query”), is caused by the bacteria Coxiella burnetti. The disease is found in every country except New Zealand and was first described in Australia in 1935. It became a notifiable disease in the United States in 1999. According to the Centers for Disease Control and Prevention (CDC), the highly infectious and persistent nature of the bacteria makes its use as a biological warfare agent a concern.
Although goats, sheep, and cattle are the primary carriers of the bacteria, camels and other livestock as well as ticks and rodents can harbor the disease. The bacteria are shed in the urine, feces, and milk of infected animals, and is released at high levels in the amniotic fluids and placenta during birthing, even though the animals themselves rarely show any symptoms of Q fever. The bacteria are highly resistant to dryness, heat, and many common disinfectants. Humans are very susceptible to the disease and typically get it by inhaling the organisms from contaminated dust. In rare cases it may be acquired by tick bites or by ingesting contaminated milk or dairy foods.
Most cases of Q fever in humans occur among veterinarians, people who work in slaughterhouses or meat processing plants, dairy workers, and military personnel who are deployed in areas such as Iraq and Afghanistan where there are many herd animals. Exposure to contaminated manure, straw, or dust that is disturbed by the wind, vehicles, or helicopters may contribute to spread of the disease.
Only about 50 percent of people who are infected with C. burnetti develop symptoms, which may include high fever, severe headache, muscle aches, confusion, sore throat, chills, nonproductive cough, nausea, vomiting, diarrhea, abdominal pain, and chest pain. Up to 50 percent of people who have symptoms then develop pneumonia, and some get hepatitis. Only 1 to 2 percent of people with acute Q fever die of the disease. If symptoms persist for six months or longer, it is considered chronic Q fever, which is rare but more serious. The most serious complication of chronic Q fever is inflammation of the heart (endocarditis).
Q fever is treated with antibiotics, with doxycycline the treatment of choice, according to the CDC. Antibiotics are most effective if they are started within the first three days of illness. Quinolone antibiotics are also beneficial. Chronic Q fever endocarditis is very difficult to treat and typically requires multiple medications over a period of years. Although there is a human vaccine for Q fever available in Australia, none is commercially available in the United States. Thus US military personnel are not vaccinated against this disease. Animal vaccines are available in Europe but not in the United States.
The recent outbreak of goat flu/Q fever in the Netherlands has brought to the public’s attention a disease that is rarely in the news in the United States. The CDC notes that the disease is underreported in America, and therefore scientists cannot reliably determine how many cases of goat flu have actually occurred around the world. One reason it is on the minds of some people in the United States is its occurrence among soldiers serving in Iraq and Afghanistan. The USA Center for Health Promotion and Preventive Medicine notes that Q fever should be considered among deployed or recently redeployed soldiers who have an illness with fever, especially if they also have pneumonia or hepatitis.
Centers for Disease Control and Prevention
USA Center for Health Promotion and Preventive Medicine, July 2007