POST TIME: 1 October, 2018 00:00 00 AM
Fomite: A common object of transmission of infection
Prof. Dr. Md. Shahidullah

Fomite: A common object of transmission of infection

A fomite is any inanimate object that can become contaminated with infectious agents and serve as a mechanism for transfer of infectious agents from there to a new host, a healthy person. Examples of fomites include pens, pencils, books, hairbrushes, towels, utensils, currency notes, doorknobs, hand rails, calling bell buttons, water taps, clothing, bedding, furniture, seat covers, cutting boards, kitchen sponges, forks, knives, spoons, toothbrushes, cups, telephones, cell phones, toys, computer key board, mouse, TV remote and many others.These substances may get contaminated with infectious microorganisms from a person.

The microbes may survive there for a period of time and then may be transferred to other individuals. These inanimate objects act as one of the most common ways that people, especially the children get sick.

The diseases that commonly spread by means of fomites include the common cold, conjunctivitis, E. coli infection, hepatitis A, giardiasis, amoebic dysentery, rotavirus diarrhoea, typhoid fever, influenza, lice infestation, meningitis, pinworms, respiratory syncitial virus infection and many others. In fact, illnesses that spread by droplet transmission through sneezing, coughing, talking. fecal-oral transmission, and contact transmission can be transmitted to countless individuals by means of fomites.

During a person’s illness, microorganisms are shed in large numbers from the body through feces, urine, saliva, nasal fluid and blood. Fomites become contaminated with these microorganisms by direct contact with body secretions or fluids. They may be contaminated by contact with soiled hands too. Again, these inanimate objects may get contaminated during talking, sneezing, coughing, vomiting or defecation. Germs commonly live on these fomites for minutes or hours or sometimes even longer. The germs can be transferred to may individuals from the fomites during this period.

Fomites consist of the nonliving objects that can become contaminated with pathogenic microorganisms. Subsequently, they serve as media in the transmission of diseases. Researchers discovered that non-porous surfaces transmit bacteria and viruses better than porous materials. So, one is more likely to pick-up a disease from a door knob than from paper money. The reason is that porous, especially fibrous, materials absorb and trap the microorganisms, making it harder to contract them through simple touch.

Unfortunately, in health care settings, the situation can be far worse. Fomites are associated particularly with hospital acquired infections, as they are possible routes to pass pathogens between patients. Stethoscopes and blood pressure instruments are two such fomites associated with health care providers.

Antibiotic-resistant bacteria may be present on blood pressure cuffs, stethoscopes, hospital beds, bed sheets, utility room sinks, bathroom taps and bathroom doors. Basic hospital equipments such as ear nose throat examination instruments, endoscopy tubes, IV drip tubes, catheters, probe of ultrasonogram machine, life support equipments, etc. can be fomites.  Fomites and pathogens are just about everywhere! Toys in a daycare or in a doctor’s waiting room may have been handled or mouthed by kids. Cutting boards and kitchen sponges may teem with bacteria from the uncooked food they have touched. Multiple toothbrushes in the same container or cup may be the way that microbes spread among the members of the family.

Still, many of these potential infection scenarios are preventable. Interruption of the spread of infection through fomites can be reduced by recognizing them, avoiding them, disinfecting them or cleansing the hands after touching them. Improved hygiene in the home can dramatically lessen the spread of fomite-borne infections. First, we should remain careful not to contaminate common inanimate objects at home.

We should disinfect these fomites or clean our hands after touching them. Simple hand washing is perhaps the easiest, cheapest, and most effective way to guard against common fomite-borne diseases. We should not put our hands into the mouth without washing them properly after touching fomites. Common sense and good personal hygiene can reduce the threat posed by the fomites.