Whooping cough

caused by the bacterium Bordetella pertussis (or B. pertussis) . It mainly affects babies younger than 6 months old who aren't yet protected by immunizations, and kids 11 to 18 years old whose immunity has started to fade.
Whooping cough causes severe coughing spells, which can sometimes end in a "whooping" sound when the child breathes in.

those of a common cold:
runny nose
sneezing
mild cough
low-grade fever
Also, there may be diarrhea at an early stage

into coughing spells. During a coughing spell, which can last for more than a minute, a child may turn red or purple. At the end of a spell, the child may make the characteristic whooping sound when breathing in or may vomit. Between spells, the child usually feels well.
While many infants and younger kids with whooping cough develop the coughing fits and accompanying whoop, not all do. And sometimes babies don't cough or whoop as older kids do. Infants may look as if they're gasping for air with a reddened face and may actually stop breathing (this is called apnea) for a few seconds during very bad spells.
Adults and teens may have milder or different symptoms, such as a prolonged cough (rather than coughing spells) or coughing without the whoop.

through tiny drops of fluid from an infected person's nose or mouth. These may become airborne when the person sneezes, coughs, or laughs. Others then can become infected by inhaling the drops or getting the drops on their hands and then touching their mouths or noses.
Infected people are most contagious during the earliest stages of the illness for up to about 2 weeks after the cough begins. Antibiotics shorten the period of contagiousness to 5 days following the start of antibiotic treatment.

of the DTaP (diphtheria, tetanus, acellular pertussis) immunization.
DTaP immunizations are routinely given in five doses before a child's sixth birthday. For additional protection in case immunity fades, experts recommend that kids ages 11-18 get a booster shot of the new combination vaccine (called Tdap), ideally when they're 11 or 12 years old.
The Tdap vaccine is similar to DTaP but with lower concentrations of diphtheria and tetanus toxoid. It also should be given to adults who did not receive it as preteens or teens. The vaccine is also recommended for all pregnant women during the second half of each pregnancy, regardless of whether or not they had the vaccine before, or when it was last given.

close contact with infants, because babies can develop severe and potentially life-threatening complications from whooping cough. An adult's immunity to whooping cough lessens over time, so getting vaccinated and protecting yourself against the infection also helps protect your infant or child from getting it.
People who live with or come into close contact with someone who has pertussis should receive antibiotics to prevent the spread of the disease, even if they've already been vaccinated against it. Young kids who have not received all five doses of the vaccine may need a booster dose if exposed to an infected family member.

symptoms) for whooping cough is usually 7 to 10 days, but can be as long as 21 days.
Duration
Pertussis usually causes prolonged symptoms — 1 to 2 weeks of common cold symptoms, followed by up to 3 months of severe coughing.
The last stage consists of another few weeks of recovery with gradual clearing of symptoms. In some children, the recovery period can last for months.

cough. To make a diagnosis, the doctor will take a medical history, do a thorough physical exam, and may take nose and throat mucus samples to be checked in a lab. Blood tests and a chest X-ray also might be done.
Whooping cough is treated with antibiotics. Many experts believe that antibiotics are most effective in shortening the length of the infection when they're given in the first stage of the illness, before coughing spells begin. But even if antibiotics are started later, they're still important because they can stop the spread of the pertussis infection to others.