Whether it’s Zika virus, Ebola or MERS (Middle East Respiratory Syndrome), there is a long list of infectious diseases that get our attention when they dominate the news. Even though these are frightening illnesses, this intense level of scrutiny of exotic diseases minimizes the real threat.

The microbes that pose the biggest threat—in terms of annual sickness rates and death—are the potentially fatal ones that we are exposed to every day, such as influenza and hospital-acquired infections known as superbugs.

Why it matters to me: My research on the transmission of infectious disease is fueled, in part, by personal tragedy. Following heart bypass surgery at a highly regarded American hospital, my mother died after contracting a type of virulent hospital-acquired bacterial infection. Hospital-acquired infections kill about 75,000 patients in the US each year. But hospitals aren’t the only place where pathogens hang out.

Most people think that they have a good idea where these germs reside. Doorknobs, elevator buttons and handrails in public places are among the best-known hot spots. But hardly anyone thinks about the numerous other places that harbor pesky pathogens.

What you need to know…

Hidden Germs

Effective handwashing removes the germs that can make you sick. But sometimes we fail to recognize hidden sources of microbial contamination, which so often do not get cleaned properly (or at all).

Many of the germs we encounter are not harmful, and a healthy immune system can often handle most of the rest. In fact, some exposure to germs helps strengthen the immune system. However, with the smart hygiene practices described below, you will greatly reduce the odds of putting yourself, your colleagues and your loved ones at risk for a variety of illnesses, ranging from the common cold to the flu and pneumonia. Germ hot spots that will surprise you…

Neckties. Some doctors have stopped wearing ties in order to protect their patients. A study at a New York hospital found that nearly half of the ties tested were contaminated with Staph, K. pneumoniae and other disease-causing organisms.

I advise all men (not just doctors) to keep in mind that ties pick up and transmit germs, since they are rarely cleaned, dangle and sweep across surfaces, and are handled frequently. Men who are not working in health-care settings are less likely to pick up drug-resistant superbugs on their ties, but risks still abound, so it’s a good idea to clean your ties now and then.

My advice: Buy ties made from microfiber—these textiles tend to resist bacterial contamination more than silk, cotton or polyester. Some ties made of cotton, linen, polyester and/or microfiber can be hand-washed with detergent, air-dried and ironed, but silk and wool usually must be dry-cleaned, which isn’t foolproof in killing germs.

Note to women: Handbags have been found to harbor deadly germs, but a sanitizing alcohol wipe can be used to clean straps and the exterior of bags. Vinyl may be easier to clean than cloth or other material.

Cell phones. Have you ever washed your smartphone? It is certainly not recommended to immerse any cell phone in water, but most people don’t even wipe off the surface of their phones.

Important finding: A 2011 British study reported that 92% of cell phones had bacteria, with 16% carrying E. coli, bacteria typically found in feces.

My advice: Clean your phone every day by wiping it down with a microfiber cloth (the kind used to clean eyeglasses) that’s been moistened with 70% ethyl or isopropyl alcohol (commonly found in drugstores). Or try other products, such as Wireless Wipes, that are made specifically for cell phones.

Another option: An ultraviolet (UV) cell-phone sanitizer, such as PhoneSoap Charger or Cellblaster, which uses exposure to UV radiation to kill most bacteria. These products are available online for about $50 to $110.

Rings and other jewelry. Whether you’re wearing a plain band or a ring with elaborate settings, bacteria can thrive underneath it—an area that’s usually missed by handwashing.

My advice: When possible, remove rings before washing your hands. You should also clean your jewelry, including wristwatches. To avoid water damage, swab the surfaces with 70% ethyl alcohol or use a UV sanitizer device (described earlier).

Paper money. On average, paper currency stays in circulation for about six years. During that time, it comes in contact with wallets, purses, sweaty palms and filthy fingertips. When we tested dollar bills that we collected as change from New York food vendors, we found that about two-thirds were contaminated with different strains of bacteria…and two-thirds of those harbored coliform (fecal) bacteria.

If you use credit cards, you can largely avoid touching money, although sometimes you must hand your credit card to the cashier, which exposes it to someone else’s germs. You also have to touch the scanner and stylus, which have been touched by many customers.

My advice: Try to cleanse your hands after handling money, especially before you eat or touch your eyes, nose or mouth. And do not lick your fingers when counting out bills. Coins aren’t germ-free, but the metal alloys in the coins tend to inhibit bacterial growth. So it’s mainly paper currency that you have to worry about.

Airports. People who travel a lot encounter germs from other travelers. In airplanes, the tray tables, armrests and seat-back pockets can be teeming with pathogens. But there are other hot spots as well.

My advice: At the airport, for example, it’s a good idea to put your cell phone, keys and other personal possessions in a Ziploc bag before putting them in a security bin, which has held innumerable shoes, phones…and who knows what.

Rental cars. Even though most rental car agencies vacuum and quickly wipe down surfaces between rentals, studies show the steering wheel may harbor nasty bacteria. Who knows where the previous drivers’ hands have been?

My advice: When you rent a car, consider wiping down the steering wheel and door handles with sanitizing alcohol wipes.