Epidemiology-of-Bed-bugs

In developed countries, there has been an increase in public awareness and media attention regarding the health consequences of bed bug bites and infestations in recent years.

This uptick in activity is a worldwide phenomenon, with an increase in the number of infestations occurring all over the world. Bed bug (Cimex Lectularius) are wingless, oval shape parasitic insects with a small (up to ¼ long) flattened body, which have over 90 species worldwide. They are blood-feeding insects that assaults on mammals, particularly in humans or birds for thousands of years. After feeding on blood of humans, colour of bed bugs changes from brown to purplish–red. Symptoms include psychological distress, loss of sleep, as well as skin rashes, dermatitis, asthma and allergic reactions Bed bugs tend to gather in hidden and undistributed places where a person sleeps, sits and extended for a period of time. They are usually found in the bed, sides and seams of the mattress and blankets, box spring, bed frame, head board cracks and crevices of walls. The recent rise in bed bugs infestation is caused due to social and environmental factors such as use of less persistent pesticides, increased resistance to insecticides, changes in pest control method and increased in international travel.

How Bed bug infection is transmitted?

Bed bugs do not fly and jump but transmitted from person to person. Bed bugs quickly crawl, suck the skin of victim and inject a chemical that numbs the skin before biting, allowing undisturbed feeding for 5minutes. Bed bugs have ability to spread near and far as they hide themselves in furniture and under clothes so when shifted from one place to others bed bugs also spread. They are not totally disappear from developed countries but locally spread through “active dispersal”, happens as a result of short distances walking, such as room-to-room travel or when they attempt to reach hosts from their dark comforting places. Bed bugs can also travel longer distances by being transported by humans in clothing, furniture and luggage through “passive dispersal”. Bed bugs are present in both tropical and temperate zones, present mainly in dark environments with more feasibility of warm-blooded hosts.

Sign and Symptoms of Bed bugs infestation:

Bed bug infestation can effect multiple body systems. A resident may not know that he/she suffer from bedbug infestation until they feel painless bites on their skin typically on neck, head, arms, legs or hands. In the absence of humans they may feed on mice, rats, chicken and other animals. After proper recognition of bedbug bites, dermal and contagious diseases are main medical problems with bugs. The most common symptoms of bed bugs bite is itchy and inflamed welts on the skin and may develop secondary infection through scratching. Victim of bed bug bite have been reported to suffer from unapparent, or small lesions to large wheals (5mm to 2cm in diameter) with a central hemorrhagic crust or vesicle at the bite side. Lesion may vary depending upon infestation intensity as well as mainly located in unclothed areas. Exceptional anemia and anaphylactic reactions have also been reported. Other reactions include bullous rashes, utricaria, dementia, psychosis, altered mentation, dermatitis and asthma.

Epidemiology of Bed bugs:

Bed bugs occur nearly worldwide. Adult bed bug lives for 6-12 months and survive without feeding for a year. Female bed bugs lay on average five eggs per night which hatch within a couple of weeks. Although there has been long association between bed bug and humans, for a period from 1950s to late 1990, this pest is relatively uncommon mainly in economically advantage nations. Prior to mid of 20th Century, bed bugs were prevalent in American households, but infestation swiftly rise after the introduction of synthetic insecticides DDT after world War II in 1990 due to environmental and social factors. Overcrowding, humidity, high human density and deprived conditions are risk factors for rapid turnover of infestation. Hence, the Mazandaran province, located in the north of Iran, is a suitable environment for bed bugs multiplication due to its humidity and dense population.

How to diagnose Bed bugs infestation:

Reports of bedbugs in hotels, apartments, motels  and houses has been increased in few past years worldwide; however, bedbug infest only a very small percentage of residence. To diagnosis of bedbug infestation is very important. History of bed bugs in an important tool to diagnose of disease. Confirming the diagnosis of a bedbug bite sometimes is difficult. Bedbugs are surely found in unclean, crowded or urban locations. A musty odor, blood strains from crushed bugs or dark red spots (faecal matter), Cast skin (empty shells of bedbug) or live crawling bedbugs on bed sheets, mattress and around bed are usually reported. Transmission of trypamosomiasis or hepatitis disease is possible and might be considered to diagnose infestation.

Treatment of bed bugs infestation:

Comfort from bed bugs can be achieved through the elimination of the active infection. For cutaneous reaction, antihistamine and tropical steroids are used to achieve ease from itching and respectively. Antiseptic or antibiotic lotions prescribed, if there is risk or presence of secondary bacterial due to scratching. However, good sanitary procedures for skin are also suggested. Psychological therapy is also needed for patients who feel severe depression or secondary delusional infestation-like syndrome. Patients having severe anaphylactic and systemic reactions, intramuscular epinephrine, corticosteroids and antihistamine are recommended. Without treatment, symptoms resolve spontaneously within 1-2 weeks since the bites are self-contained, but permanent post-inflammatory scars remain from weeks to months.    

How to prevent bed bugs infestation:

Although it is difficult to completely eliminate bed bugs, risk management can help to reduce their impact. First preventive measure is early detection that would help to minimize the chance of infection and control is easier to accomplish. Regular and comprehensive inspections by housekeeping personnel and the pest management during normal room maintenance are critical components of early detection. Protective Clothing include hat, long sleeves shirt and long pants helps to prevent bed bug bite. Light colour dresses and bright environment could help to prevent bed bug infestation as they will visible in these conditions. Pets are also source of bedbugs so there should be proper management while handling them. Always look for signs of bed bugs in hotel/resort/hostel rooms (examine folds of bed mattress, bedding, cracks and crevices of bed frame) during travelling. Prior to coming from travelling, always inspect cloths, baggage and folds of suitcases thoroughly. Pay attention while buying furniture and avoid buying used bed frames and mattresses.

Control measurement of Bed bug:

The low rate of infestation could be due to the proper health from prompt treatment by people through improvement in sanitation and increment use of residual insecticides. Bed bug eradication is mostly dependent on good collaboration between the owner of the pest-infested property and the pest management for site assessment, inspection, identification, and eradication. Reduce clutter to make it harder for bedbugs to hide. Clean infested rooms, vacuum carpets, furniture, bed mattresses and frames, and dismantle all furniture to reach all bedbug hiding spots, identifying and destroying eggs, nymphs, and adults. Cockroach aerosol pesticides are quick killing chemicals that may be sprayed to the afflicted region and for these purpose remnant insecticides is usually spread by professionals during inspection process.

Some strategies can also reduce the chance of infection or spread: attractive traps, use of pesticides, recruiting of professional pest control manager, regular inspection, hygiene procedures cleaning and organization of living areas, removal of bleeding and clothing from affected areas, washing sheets and blankets, drying in hot setting and targeted use of insecticides as well as basic education of people. Complementary actions includes: Modifying room temperature, destroying neighboring bird homes, removing peeling paint and plaster, and caulking or cracking any holes in the walls, ceiling, and around baseboards.  

Authors

1. Aarzoo Ashraf, M.Phil. Epidemiology and Public health, University of Agriculture, Faisalabad.

2.Muhammad Sohail Sajid, Chairman Dept. of Parasitology, University of Agriculture, Faisalabad.

By Aarzoo Ashraf

Well ,its Aarzoo Ashraf here (Nutritionist). Currently, I'm a student of M.Phil Epidemiology and Public Health from the University of agriculture Faisalabad.