When I was a medical student, I knew a little about a lot. As I graduated and started surgical training, I grew to learn quite a bit more about quite a lot less. I then became a surgical specialist and knew a great deal about very little and, continued to the obvious conclusion, I will soon know absolutely everything about nothing at all!
So when I found myself thinking about summer months and the sights, smells. and sounds of this time of year, a topic that buzzed into my mind was insects. And it bugged me that nobody knows how many species there are – estimates range from 2–10 million, and less than one million have been characterized.
The stuff of phobias and horror movies, insects can also be purveyors of some rather nasty diseases, so I thought it worth reviewing some of the cream of the creepy crawlies capable of causing corporeal complaints. Not all are common and some are just plain interesting to me. To put it into context, for one bug alone there over 700 million cases of mosquito-borne illness annually worldwide as referenced below. While a sting is the issue with bees, wasps or spiders, in other cases, as with malaria, for example, an insect can be a vector, or vehicle, to transmit an infectious organism from one animal to another; the primary to secondary host. The life cycle of some of these transmitted infections can be quite fascinating. And some are pretty gross.
- Lyme disease is transmitted by the bite of a deer tick (or black-legged tick), which are notoriously small and, therefore, hard to see. Common in the mid-Atlantic, northeast and north-central USA (the western black-legged tick spreads the disease in the Pacific coastal region), like all ticks, these little fiends “cement” their mouthparts to the unwitting new human host and burrow into a blood vessel near the surface of the skin. The infectious organism that causes Lyme disease (so called because it was first described in Old Lyme, Connecticut) is Borrelia burgdorferi and it usually takes 1–2 days of attachment before an infection takes hold. Diagnosed by suspicion, or the typical “bull’s-eye” rash, obtaining laboratory confirmation is challenging and awareness is very important. I admire the work of singer Daryl Hall a while back raising the profile of this disease that can cause diverse symptoms such as fatigue, joint pain, kidney, and other problems. Although there is promise of better lab tests coming down the line, the mainstay of treatment is aggressive antibiotic treatment.
- When I went for a walk in some Virginia coastal woodland stupidly wearing open sandals, I was horrified to return to my friend’s cabin with intensely itchy feet, and more horrified to see tiny little red-black specks moving under my skin. Chiggers. An obscenely unpleasant affliction, these spider mite larvae use saliva to dissolve and then create a tube under the host’s skin. Although they itch like the dickens, they do not transmit disease. One should wash well with soap and water to drive away those devils that have not taken up residence, apply ice and hydrocortisone cream and avoid scratching as that can lead to infection.
- Rocky Mountain spotted fever (RMSF) is a serious bacterial infection caused by a bug with the poetic-sounding name Rickettsia rickettsia. It is transmitted by several ticks, and is not just found in the Rocky Mountains, but throughout the USA. The disease presents with fever, headache, and rash. Without treatment, RMSF is potentially deadly but antibiotics (doxycycline) are curative.
- The lone star tick does not just infest Texas but has a hold in much of the USA and can transmit several bacterial diseases all known as Ehrlichiosis. Presenting with similar symptoms to RMSF, together with fatigue and aching muscles, a diagnosis via special lab tests can take weeks. In some cases, a delayed reaction is an allergic reaction every time the infected person eats red meat. When I first heard this I was astonished; researchers at UVA in Charlottesville, my adopted home town, had discovered something that truly sounded like a horror movie symptom. What’s next? I thought. Allergies to chocolate?
- Dengue fever (“den-gee”) is a viral disease passed on by infected mosquitoes and causes a painful and exhausting illness, similar in some regards to West Nile virus and yellow fever. It is very common around the world including the Caribbean (except Cayman Islands and Cuba) and although reported in the USA, it is likely most cases were in people who had traveled here from overseas, although there have been outbreaks in the USA.
- Zika virus, passed on once again by pesky mosquitoes, made the news a few years back as the cause for women giving birth to children with various birth defects including microcephaly, or “small head.” Although mosquito bites are the primary form of infection, the virus can also be passed by sexual contact. For these reasons, it has been recommended that pregnant women should avoid travel to Zika-infested areas and infected (or potentially infected) men should use protective means such as condoms during any sexual contact.
- Malaria is yet another illness passed on by the all-too-generous mosquito which donates a parasitic infection. The disease is characterized by intermittent high fever, rigors (shaking chills) and feeling pretty wretched. It can lead to fatal complications and still afflicts millions of people around the world, with those in the USA almost invariably being foreign travelers. If going to infected areas of the world, please see a specialist before traveling and obtain suitable prophylaxis.
- West Nile is also a viral disease disseminated by mosquito bites, and it pops up all over the USA during warmer weather when the bugs are breeding, standing water is available around the home and people are not covered head to toe. In most cases there are no symptoms, but when present (around 20%) it causes a flu-like illness, but can be serious and even fatal. Unfortunately, there are no effective vaccines or treatments yet.
- Fire ants are an example of an invasive species; i.e., one that was not originally in the country and in this case, the red imported fire ant (RIFA) was inadvertently introduced in shipping crates. The problem with such introductions is that the new species lacks a natural predator and can expand territory in an uncontrolled manner. In America, RIFA cause about $5–6 billion/year in damage and medical expenses and are mostly found in the southern, subtropical states like Florida, Louisiana, Georgia and Alabama. As for the damage they will do to you? If you disturb a nest, countless of these little monsters will latch on and sting multiple times, a sensation akin to having numerous burns. Avoid them like the plague they are!
- Bedbugs – for number ten in my list of noxious nuisances I am selecting a nocturnal nemesis, the ubiquitous bedbug. I first alerted the flying community to these critters in an AOPA Pilot magazine article entitled “Sleep Tight” in the November 2011 edition. Since then, the plague has continued unabated – never check in to a hotel without (a) checking an online resource for reports of infestations at that hotel and (b) checking your room before bedding down for the night. Unless you don’t mind being literally eaten alive! And class of hotel has no relevance – there have been reports at all sorts of establishments from flop houses to five-star resorts.
But the best advice is to avoid bugs at all costs. In summer months where possible, cover up especially when hiking through tall grasses or similar environs. Apply bug spray to all exposed skin, and when returning from a walk, inspect your body for unwelcome visitors. Make sure there is no unnecessary standing water around your home, such as in a wheelbarrow after a rain shower.
If you have traveled to a Zika zone, use bug spray every day for three weeks or more so that if you are infected, you will not be a pool from which mosquitoes back home can feed and transmit to others.
If you find a tick has taken hold, there are specific ways to remove it – tweezers and a gentle, insistent twisting motion. Freezing these devious denizens of the dermis with wart spray also works. Recently, I had returned from a run in the park with plans to meet a pal who is an esteemed neurosurgeon later that day. As I arrived, I noted a little bump on the back of my neck and asked him to look. He confirmed it was a tick and, as no tweezers were to be found I can proudly tell you he removed it with a can opener and a fork; please don’t try this at home!
Finally, if you have been somewhere tick infested and feel unwell, see your doctor promptly to be tested and treated for one of the above conditions or one of the many others that insects can induce.
Enjoy the rest of the summer!