What is Kissing Bug Bite?

The term ‘kissing bug’ is an everyday name used to describe different types of insects in the Triatominae family. These insects are often attracted to uncovered areas of skin, particularly the face, and that’s why they are commonly termed as ‘kissing bugs’. They are significant because they can transfer a harmful parasite called Trypanosoma cruzi (T. cruzi), which is responsible for Chagas disease.

Symptoms of Chagas disease were noticed as early as the 19th century, but it became officially recognized in 1909 when Carlos Chagas, after whom the disease is named, documented a case in his publication.

Chagas disease can be hard to diagnose, and often becomes a long-term health issue. It can seriously harm a person’s health and even poses a risk of death. Moreover, with the advent of globalization and growing concerns about the spread of insects that carry the disease, there’s a need for increased awareness about Chagas disease.

What Causes Kissing Bug Bite?

Chagas disease, also known as American trypanosomiasis, is an infection caused by a parasite named T. cruzi. This disease is transmitted by an insect called a triatomine, which gets infected with the parasite after biting an infected mammal. More than 24 types of mammals, including humans, raccoons, opossums, wood rats, cats, and dogs can carry this infection. In North America, there are not just 140 species of triatomines, but only about forty species actually transmit the disease.

The transmission process starts with the T. cruzi parasite entering the gut of the triatomine, or “kissing bug”, after an incubation period. The disease is then transmitted to other hosts when an infected kissing bug bites and deposits its feces, which contain the parasite, onto the skin or mucus membranes of the host. The feces are typically deposited during or after feeding, but not every bite results in an infection. Once inside the host, the T. cruzi parasite enters the blood, spreads to various tissues, multiplies, and then re-enters the bloodstream, where it can be picked up by other kissing bugs during their feedings.

Furthermore, in addition to this insect-based transmission, there have been cases where the disease was spread through blood donations, from mother to child during pregnancy, through food contaminated with the feces of an infected vector, organ transplants from infected donors, and migration of people from areas where Chagas disease is common to areas where it is not.

Risk Factors and Frequency for Kissing Bug Bite

Chagas disease is a global problem affecting an estimated six to 8 million people, many of whom don’t even know they are infected. This disease is particularly common in many countries of Central and South America, with the highest rates seen in Bolivia and Argentina. In these areas, around 28,000 new Chagas disease cases are reported each year, with Bolivia reaching up to six cases for every 100 people, typically in poorer, rural regions where the disease-spreading “kissing bug” thrives.

The disease also affects the United States, particularly Latin American immigrants, with over 300,000 cases estimated. The “kissing bug”, known to carry the disease, is common in states along the border with Mexico, like Texas, and its bites have been reported as far north as Delaware and Maine. The spread of Chagas disease is driven by a combination of infected individuals being bitten by the bug, and people moving from rural to urban areas. The true number of people with Chagas disease, especially heart problems caused by it, might be underestimated in the United States.

The risk of contracting Chagas disease also exists through blood transfusion and organ transplants. Approximately 0.02% of blood donors in the U.S. carry the disease, and if people receive infected blood, 10% to 20% of them will get Chagas disease. One study found that 0.3% of pregnant women were infected with the disease. Organ transplants from infected individuals also come with risk – around 18% to 19% for kidney transplants and 29% for liver transplants. Heart transplants from infected donors are discouraged. Moreover, up to 20% of HIV-infected patients may experience a reactivation of T. cruzi, the parasite causing Chagas disease.

Signs and Symptoms of Kissing Bug Bite

Chagas disease is a condition that often goes unnoticed in its early stages as it typically doesn’t cause symptoms. When symptoms do appear, they’re usually vague and can be easily confused with symptoms of other illnesses. However, some common signs of Chagas disease can include:

No symptoms (asymptomatic)
Fever
Feeling unwell (malaise)
A nodule at the site of entry of the infection (chagoma)
Swelling of an eyelid, usually on one side (Romana sign)
Swollen lymph glands
Enlarged liver or spleen (hepatosplenomegaly)

These symptoms typically develop over a four to eight week period. If the disease was contracted through mouth, other symptoms can include nausea, vomiting, diarrhea, stomach pain, or bleeding in the gastrointestinal tract. Although acute infection usually resolves on its own, some severe and uncommon symptoms related to specific organs might include inflammation of the heart muscle (myocarditis) or inflammation of the brain and spinal cord (meningoencephalitis). In babies obtained from infected mothers, Chagas disease can cause premature birth, low birth weight, fever, anemia, and low muscle tone.

In some people, the bug bite that spreads Chagas disease might lead to an allergic reaction. The person might develop a rash, redness of the skin, breathing difficulties, wheezing, nausea, vomiting, diarrhea, a fast heartbeat, and swelling.

Between 30% to 40% of people with Chagas disease will develop a chronic form of the disease, which can damage the body’s organs. The most common organ affected is the heart but the disease can also impact the gastrointestinal tract. Depending on the type and extent of organ dysfunction, symptoms can vary, which might include heart block, fainting, shortness of breath, chest pain, or sudden cardiac death for heart diseases; and, swallowing difficulties, nausea, vomiting, abdominal swelling, and abdominal pain for gastrointestinal issues.

People with weakened immune systems can see a resurgence or “reactivation” of Chagas disease. This could include symptoms such as chagoma, inflammation of the fatty layer of the skin (panniculitis), myocarditis, or meningoencephalitis.

Testing for Kissing Bug Bite

During the early stage of Chagas disease, the number of parasites in the blood is high. Therefore, doctors diagnose the disease by looking for these parasites under a microscope, often using a sample of the patient’s blood. Occasionally, they could also use other body fluids like cerebrospinal fluid, which is fluid around the brain and spinal cord. The polymerase chain reaction (PCR) test, a type of test that amplifies and detects DNA, may be more accurate at detecting these parasites. Sometimes, doctors also use PCR tests to monitor the disease or if they suspect it may become active again. For infants who may have been exposed to the disease in the womb but it wasn’t detected at birth, doctors can run a specific kind of blood test when the infant is roughly nine months old.

In the later or chronic phase of Chagas disease, the number of parasites in the blood reduces and thus, the PCR test becomes less dependable. Instead, doctors turn to tests that can detect antibodies made by the immune system to combat the T. cruzi parasite. These tests usually involve techniques like enzyme-linked immunosorbent assays (ELISA) or immunofluorescent antibody tests (IFAT), both of which detect a type of immune molecule called IgG. But these tests aren’t always perfect, so doctors often suggest running two different tests to increase accuracy. For certain situations such as early detection in infants or in organ transplant recipients, a molecular test that identifies specific DNA sequences may be recommended.

When a patient is confirmed to have Chagas disease, it’s crucial to check whether the disease has affected other vital organs of the body. The doctor will ask the patient about any symptoms they might have experienced. They’ll typically perform a heart assessment, including an electrocardiogram and echocardiogram, which are tests that monitor the heart’s activity and structure. If a patient reports gastrointestinal symptoms, the doctor may recommend a barium swallow test or barium enema. These tests involve filling the digestive tract with a chalky substance called barium, which helps make the area visible on an X-ray.

Treatment Options for Kissing Bug Bite

Doctors consider specific antiparasitic treatment for acute infections of a disease called Chagas, as well as for congenital or reactivated forms of the disease, indeterminate cases, women of childbearing age, high-risk exposures, and chronic cases in children under 18 years. Treatment may also be necessary for patients with weakened immune systems. However, the decision whether to treat adults with chronic Chagas disease or Chagas related heart problems is less straightforward.

The two medications currently used to treat Chagas disease are benznidazole and nifurtimox. There is no clear guidance on which medicine should be used as the first choice, but in the United States, benznidazole is often used because it’s more readily available. The Food and Drug Administration (FDA) approved benznidazole in 2017. A common side-effect of benznidazole is skin inflammation; more serious side effects can include bone marrow suppression and nerve damage.

Nifurtimox, the other antiparasitic therapy, isn’t currently FDA approved but can be obtained through the Centers for Disease Control and Prevention (CDC) in certain cases. Side effects of Nifurtimox can include nausea and vomiting, nerve damage, and negative effects on mental functions.

The success rate of these treatments can vary depending on several factors like the patient’s age, the stage of the disease, and how long the patient has been infected. During the acute or early phase of the disease, treatment is successful in 80% to 90% of cases, but in chronic disease, this falls to between 20% and 60%. Children usually respond better to treatment, and early screening and treatment can lead to better outcomes.

Patients with a history of Chagas disease who later have an organ transplant should be monitored regularly for signs of reactivation of the disease.

Treatment for complications of Chagas disease, such as rhythm disturbances and heart muscle disease, should follow current recommended treatments for those specific conditions. For example, a pacemaker or implanted cardioverter-defibrillator can be used to treat abnormal heart rhythms, and medications like amiodarone can help with recurrent dangerous heart rhythms. In cases of severe heart muscle disease, heart transplantation might be needed.

The use of antiparasitic therapy for established Chagas-related heart muscle disease is a topic of ongoing debate. In one study, the use of antiparasitic treatment in patients with this condition produced higher rates of reducing the detectable levels of the disease, but it didn’t seem to improve their symptoms or disease progression. Despite mixed results, some experts continue to recommend that Chagas-related heart disease be treated with antiparasitic therapy.

The symptoms of Chagas disease can fairly vague, often appearing similar to other illnesses, so it can be hard to diagnose. The signs can also suggest issues in various body systems. During the early stages, its symptoms, such as fever and fatigue, can look like a lot of other diseases that cause high temperature. One-sided eye swelling could be mistaken for a condition involving infection around the eye. Lastly, a Chagas rash could be thought to be a reaction to an insect bite or another kind of skin inflammation.

Here’s a list of conditions that might be considered when trying to diagnose Chagas disease:

Achalasia (swallowing disorder)
Acute colonic pseudo-obstruction (gut blockage)
Angina (chest pain due to reduced blood flow)
Atrioventricular block (heart condition)
Dissociation of atrioventricular
Chronic megacolon (enlarged colon)
Colonic Obstruction (block in the colon)
Constipation
Atherosclerosis of coronary artery (heart disease)
Dilated cardiomyopathy (heart muscle disease)
Esophageal motility disorders (swallowing disorders)
Esophagitis (inflammation of the esophagus)
Gastroesophageal reflux disease (GERD — a chronic digestive disease)
Hypertrophic cardiomyopathy (a disease in which the heart muscle becomes abnormally thick)
Leishmaniasis (parasitic disease)
Malaria
Meningitis
Myocardial rupture (a tear in the heart muscle)
Myocarditis (inflammation of the heart muscle)
Pulmonary regurgitation (a heart valve disorder)
Syncope (fainting)
Third-degree atrioventricular block (heart rhythm problem)
Toxic megacolon (expansion of the large intestine)
Toxoplasmosis (a parasite infection)

What to expect with Kissing Bug Bite

In the early stages of a certain disease, between 1% to 5% of patients may experience severe symptoms. The death rate for these patients may range from 0.2% to 0.5%. Among patients who progress to a chronic, or long-term, stage of the disease, about 10% may experience noticeable organ dysfunction, while 20% may have organ involvement without symptoms.

It’s estimated that roughly 12,000 people die each year due to this disease, known as Chagas disease. However, the severity of illness and death rates can vary significantly depending on how the infection was acquired.

Possible Complications When Diagnosed with Kissing Bug Bite

During the initial phase of infection, one may experience serious health issues, such as:

Myocarditis: an inflammation of the heart muscle
Pericardial effusion: a condition where fluid builds up around the heart
Encephalitis: inflammation of the brain
Meningoencephalitis: inflammation of the brain and the membrane surrounding it

In the long-term or chronic phase of the infection, complications may include:

Heart failure: a condition where the heart can’t pump well enough to meet the body’s needs
Arrhythmias: irregular heartbeats
Thromboembolic disease: a condition where blood clots form in blood vessels and can travel to other parts of the body
Megaesophagus: a major enlargement of the esophagus, which is the tube that carries food from the mouth to the stomach
Megacolon: extreme enlargement of the colon, which is part of the large intestine
Neuropathy: a nerve problem causing weakness, pain, or numbness

Preventing Kissing Bug Bite

The main way to prevent the spread of disease is to control the insects that carry it. This can be done using methods like insecticides. There’s also a big focus on improving living conditions. Strategies to protect people include getting rid of homes made of mud in developing countries and using bed nets to keep bugs away. Other methods include testing blood products, organ donors, and pregnant patients to make sure they aren’t carrying the disease.