It takes very little effort to avoid a big problem with infectious diseases transmitted by bugs.
The World Health Organization focused on vector-borne diseases as its theme for World Health Day on April 7. World Health Day marks the anniversary of the WHO being established in 1948. A theme is picked each year to highlight a public health priority, and this year it’s all about bugs and the diseases they carry.
Dr. Nancy F. Crum-Cianflone, who specializes in infectious diseases in a San Diego physicians’ practice with Dr. Gonzalo R. Ballon-Landa, said there is good reason to become educated about infections carried by bugs, as many such diseases are present in Southern California. The Centers for Disease Control reported that there were 500 reported cases of West Nile virus in California in 2012. Twenty people died from the disease, which is carried by mosquitoes.
“Tick-borne diseases are less common in San Diego compared with the eastern parts of the U.S., but still occur,” Crum-Cianflone said.
The most common, Lyme disease, is reported in approximately 100 cases a year in California, she said.
These diseases shouldn’t be taken lightly, and West Nile virus and Lyme disease aren’t the only diseases carried by bugs, she said.
“A variety of bugs and insects can carry infectious agents that can lead to human infections,” Crum-Cianflone said. “After a bug bite, viruses or bacteria that the bug carries can make people sick.”
Besides Lyme disease, ticks can also carry Rocky Mountain spotted fever and ehrlichiosis, which is a general term used to include a number of bacterial diseases that affect both humans and animals.
The West Nile virus can be very serious because it can cause fevers and occasionally leads to meningitis, Crum-Cianflone said. One-fifth of those infected develop symptoms that include fevers and flu-like illness. Crum-Cianflone said one in 150 of those infections develop into an infection in the brain, which is then classified as meningitis. Those symptoms include fever, stiff neck, headache and, in some cases, confusion, she said.
Lyme disease can be dangerous as well, Crum-Cianflone said. Symptoms of Lyme disease include a rash that appears as a red, circular area with a partial center clearing resembling a bull’s-eye, fever, swollen lymph nodes, joint aches and headaches.
Crum-Cianflone said prevention is key in dealing with these diseases because there are no vaccines to protect the public from them.
Prevention is easy and doesn’t cost much, she said.
The best way to prevent infectious diseases stemming from bugs is to avoid bugs. That means staying out of wooded or bushy areas. Those who hike or do other outdoor activities should implement other preventive measures, such as using an insect repellent containing a 20 to 30 percent N,N-Diethyl-meta-toluamide (DEET), which is the active ingredient in repellents, she said. Those spending time outdoors need to wear long-sleeve shirts and pants to protect against insect bites, the doctors said.
“Young children can be protected by putting a fine netting over strollers and baby carriers,” Crum-Cianflone said.
Property owners should drain all standing water and cover swimming pools to prevent mosquitoes from breeding, she said. That includes draining empty flower pots, wheelbarrows and tires that may be on the property.
Crum-Cianflone said people should clear tall grasses and brush around the home and around lawn edges to prevent ticks. Parents need to check their children for ticks after they’ve been playing outside, and pet owners need to inspect their animals if they stay outside for any length of time. Campers and hikers, need to check their bodies for ticks once they exit the woods, the doctor said, and ticks that are discovered should be promptly removed.
The good news, according to Crum-Cianflone, is that these infections can’t be transmitted from human to human.
“Persons with these infections are not contagious,” she said. “The exception is that they can be passed through blood transfusions. However, blood is typically screened for agents like (West Nile virus) prior to use.”