Even if this is your baby's first winter, you're probably prepared for a few cases of the sniffles. It's those other winter bugs -- the ones that can cause soaring fevers or awful coughs -- that leave you rattled. But not for long. We walk you through the latest research on seasonal bugs that strike babies and provide expert tips on the best ways to fight back.

"How can I tell the difference between a cold and the flu?"

Fatigue, fever, cough and runny nose are classic signs of the flu, but some infants' only symptoms may be irritability, difficulty sleeping and rapid breathing, says Robert Baltimore, M.D., professor of pediatrics and epidemiology at Yale University in New Haven, Connecticut. A characteristic of the H1N1 flu is vomiting and diarrhea. A simple cold will generally not prompt fevers, phlegmy coughs or severe irritability.

Babies are among the most vulnerable to complications from flu viruses, including dehydration (watch for fewer wet diapers and/or dark urine), ear infections and bacterial pneumonia, which is often characterized by a high fever, severe coughing and trouble breathing. This is why seasonal and H1N1 flu vaccines are so strongly recommended for babies 6 months and older. If your infant is younger than that, everyone in your family -- and anyone who has regular close contact -- should be immunized for both the seasonal flu and the H1N1 flu, says Jennifer Shu, M.D., coauthor of Heading Home With Your Newborn (American Academy of Pediatrics). The flu season often doesn't peak until March, so your child could still benefit from getting the vaccine now.

Best Treatments:  The virus often takes a week or more to run its course, so all you can do is ease her symptoms. Offer formula or the breast more frequently to prevent dehydration; consider elevating the mattress in her crib, and use saline nose drops and/or a humidifier to relieve stuffiness. You can also try a nasal aspirator to suction out mucus. Ask your doctor about giving a pain/fever reducer to help keep her comfortable.

"What if the cough is persistent and severe?"

Pertussis (also known as whooping cough) is a highly contagious bacterial infection that is tricky to catch early because it starts out like a cold, with sneezing, runny nose and a mild cough, which usually worsens after the first few days of infection. Then after one or two weeks, often after the cold symptoms appear to subside, severe coughing spells begin. Babies will cough repeatedly (sometimes 10 to 15 times in a row), then take in a high-pitched breath (the whooping sound). Vomiting may follow. Prepare yourself: The cough can last as long as six weeks. Babies younger than 6 months are especially vulnerable because they're too young to be fully vaccinated. Up to 75 percent of infants younger than 6 months old who contract the disease must be hospitalized.

Best Treatments:  The CDC recommends that all adults receive the pertussis booster Tdap if it's been 10 years since their last shot (and sometimes sooner). This is because about 90 percent of susceptible people in a home contract whooping cough after exposure, and babies can catch the illness from parents or siblings whose immunity has waned. The shot is recommended for babies at 2, 4 and 6 months, with boosters at 15 to 18 months and 4 to 6 years. If your baby develops cold symptoms after coming in contact with someone with whooping cough, your doctor may start antibiotics immediately, which can shorten the course, the severity and the spread.

For an infant diagnosed with the full-blown illness, expect a course of antibiotics to prevent further transmission. Though it's difficult to watch your baby coughing relentlessly, the most important thing you can do is to try to keep him calm -- read to him, play soothing music, give lots of hugs -- whatever works. You can also use a cool-mist vaporizer to help loosen respiratory secretions and soothe irritated lungs and breathing passages. (Be sure to follow directions for keeping the vaporizer clean and mold-free.) In addition, keep your home free of irritants that can trigger coughing spells, such as aerosol sprays, tobacco smoke, and smoke from cooking, fireplaces and wood-burning stoves. Children with whooping cough may vomit or not eat or drink much because of frequent coughing. Offer smaller, more frequent meals and encourage your child to drink lots of fluids.