Cockroaches — the creepy crawlies that live rent-free in our homes — are one of the most common household pests. These insects, which are synonymous with filth and grime, are notorious for harboring bacteria and viruses. However, what is largely unknown about them is that they can also trigger allergic reactions. Cockroach allergy, triggered by cockroach droppings, saliva and body parts is a very common yet underdiagnosed indoor allergy.
What causes cockroach allergy?
Dr Hitesh Billa, consultant interventional pulmonologist, allergy and asthma specialist, Apollo Clinics and Apollo Institute of Medical Science & Research, Hyderabad, explains that cockroach allergy is triggered by cockroach saliva, droppings, or body parts. “The immune system of an affected person mistakenly identifies these substances as harmful invaders,” he adds.
Further, he says that the immune system releases chemicals like histamine to combat what it perceives as a threat, thereby triggering an allergic reaction.
Symptoms of cockroach allergy
“Cockroach allergy is strongly associated with asthma, particularly among children and young adults living in urban areas, where cockroach infestations are more prevalent,” says Dr Billa.
He shares the different symptoms of cockroach allergy:
- Sneezing
- Runny nose
- Itchy and watery eyes
- Stuffy nose
- Rashes
- Breathing difficulties
- Chest tightness
- Coughing
- Wheezing
How do roaches get into our houses?
According to Dr Arif Ahmed, consultant pediatrician and allergist, Allermy Centre For Allergy And Chest Diseases, Hyderabad, cockroaches thrive in warm and moist environments with easy access to food, water and shelter, making the kitchen and bathrooms hotspots for their activity.
Cockroaches enter buildings through small holes, cracks and crevices, pipes and drains. They are usually reclusive during the day and sneak out at night. “Spotting a cockroach during the day is an indication that there are hundreds hiding, hinting at a severe infestation,” says Dr Ahmed.
Due to their affinity towards warm and humid conditions, the summer months are a gala time for roaches. They venture out of their hiding places more often in summers than in winters. Besides, the warm months are also their breeding season. Thus, the population increases rapidly during these months, making cockroach allergy more concerning.
How do cockroach allergens get transmitted?
“Cockroach allergens settle in dust, furnishings and fabrics, including bedding. They are stirred up during activities like sweeping and vacuuming, contaminating the indoor air. Inhaling these particles can trigger an allergic reaction in vulnerable people,” says Dr Meghana Potluri, consultant, allergy and immunology, Manipal Hospitals, Varthur, Bangalore.
Dr Potluri points out that dust mites and cockroaches tend to cross-react, that is, the same antibodies triggered by the cockroach antigen are also triggered by the dust mite antigen. Moreover, those who test positive for cockroach allergy often also test positive for dust mite allergy.
Identifying and treating cockroach allergy
Cockroach allergy can be diagnosed through a skin prick test, as well as a blood test, to identify the specific allergen triggering the symptoms and choose the appropriate treatment. Dr Potluri recounts the case of a 28-year-old chef from Bangalore who was on antiallergic tablets, nasal sprays and inhalers for 12 years for severe sneezing and asthma. “While she was on medication, she had not undergone any tests for allergies yet. Its results revealed that she was allergic to both dust mites and cockroaches,” says Dr Potluri. Being a chef, she was exposed to cockroach-infested kitchens, which would trigger her allergy. Following the diagnosis, doctors could help her manage the condition more effectively.
Dr Billa says, “Treatment involves cockroach eradication, symptom management and immunotherapy.”
Preventing cockroach infestation and allergies
Dr Ahmed lists some ways to prevent cockroach infestation:
- Do not leave food open
- Refrain from leaving unwashed dishes in the sink
- Avoid taking food into the bedroom
- Clean up food morsels
- Seal cracks and crevices
- Use insect traps and insecticides
- Hire professional pest control every six months
Dr Billa warns against using insecticides containing boric acid. “These can worsen asthma because when you inhale high concentrations of boric acid, it can irritate the respiratory system and trigger asthma symptoms,” he says.
Further, he advises people with a cockroach allergy against staying indoors when insecticides are being sprayed, as both the fumes and cockroaches fleeing from it can worsen allergy and asthma symptoms.
Takeaways
- Cockroach droppings, body parts and saliva can trigger allergic reactions in some.
- Cockroaches thrive in warm and humid conditions, making their infestation more common in summer months.
- Symptoms of cockroach allergy include asthma, rashes and an itchy and runny nose.
- Preventive measures include sealing cracks, maintaining hygiene and opting for pest control every six months.
