Kissing bug bite – a kiss you would not want
It was the summer of 2005 if I recall correctly, I was just sitting on the couch watching TV. Suddenly I felt something like a fine needle prick on my left elbow. Turning to take a look, I faintly saw something, an insect scurry down the arm rest and disappeared underneath the couch. Not more than an hour later, there was swelling and intense itchiness on that elbow.
It worsened that night I wasn’t able to sleep well. The following morning, my elbow had swollen up and was itchy as hell. Hydro cortisone cream and anti-histamines finally gave some relief. The whole ordeal lasted for almost 5 days.
The culprit was the kissing bug, an insect belonging to the subfamily Triatominae. Also known as assassin bugs, the specie found in the Philippines is Triatoma rubrofasciata.
These insects are active during the night, feeding on the blood of dogs, raccoons, rodents and humans. The name ‘kissing bug’ came from their habit of drawing blood near the mouth or around the eyes as the skin on these parts of the human body are easier to pierce.
Their saliva contains chemicals that causes itchiness, swelling and in some cases severe allergic reactions that can be fatal.
However, the bite of the kisser bug is minor compared to something else: its feces. Aside from drawing blood near the mouth, the kisser bug has another, more unnerving habit: after feeding, it defecates near the bite mark. Its feces contains a parasite that causes Chagas disease.
From the Center for Disease Control website:
Chagas disease is caused by the parasite Trypanosoma cruzi, which is transmitted to animals and people by insect vectors that are found only in the Americas (mainly, in rural areas of Latin America where poverty is widespread). Chagas disease (T. cruzi infection) is also referred to as American trypanosomiasis.
What are the signs and symptoms of Chagas disease?
The acute phase lasts for the first few weeks or months of infection. It usually occurs unnoticed because it is symptom free or exhibits only mild symptoms and signs that are not unique to Chagas disease. The symptoms noted by the patient can include fever, fatigue, body aches, headache, and rash. The signs on physical examination can include mild enlargement of the liver or spleen, swollen glands, and local swelling (a chagoma) where the parasite entered the body. The most recognized marker of acute Chagas disease is called Romaña’s sign, which includes swelling of the eyelids on the side of the face near the bite wound or where the bug feces were deposited or accidentally rubbed into the eye. Even if symptoms develop during the acute phase, they usually fade away on their own, within a few weeks or months. Although the symptoms resolve, if untreated the infection persists. Rarely, young children (<5%) die from severe inflammation/infection of the heart muscle (myocarditis) or brain (meningoencephalitis). The acute phase also can be severe in people with weakened immune systems.
During the chronic phase, the infection may remain silent for decades or even for life. However, some people develop:
cardiac complications, which can include an enlarged heart (cardiomyopathy), heart failure, altered heart rate or rhythm, and cardiac arrest (sudden death); and/or
intestinal complications, which can include an enlarged esophagus (megaesophagus) or colon (megacolon) and can lead to difficulties with eating or with passing stool.
– Center for Disease Control, FAQ on Chagas Disease
The average life-time risk of developing one or more of these complications is about 30%.
Fortunately, Chagas disease is now very treatable. What’s important is to get tested soon after being bitten by a kissing bug.
The best way to avoid having the disease is to avoid being bitten by a kissing bug. Regularly cleaning the house, sleeping under a mosquito net, closing gaps and openings in our houses are effective ways.
Checking your bedroom for these insects before going to bed is a also a good practice. While the prevalence of Chagas disease in the Philippines is very, very low, prevention is still key.