Whooping cough: 8 things you need to know Robyn Beck / AFP/Getty Images Pharmacist Kristy Hennessee administers a vaccination against whooping cough (pertussis), in Pasadena, Calif., on September 17, 2010. By NBC's Robert Bazell and contributor Joyce Ho Today the Centers for Disease Control announced there are more cases of whooping cough than they've seen in five decades. Why is it happening and what can you do to protect yourself? Below, find answers to frequently asked questions about this highly contagious illness. Why are so many outbreaks happening in 2012? The reasons for the current outbreaks of whooping cough, also known as pertussis, and what should be done to contain them are not especially clear. The reason is that one of the factors contributing to these outbreaks is a vaccine that is not as effective as everyone wants. Until 1997, the pertussis vaccine contained whole killed bacteria and it was extremely potent. But many doctors and parents believed the vaccine had an unacceptably large number of side effects. As a result, scientists developed a vaccine that contains only five proteins from the bacteria. This new vaccine is much safer but not quite as effective as the older one. That is why in some people immunity wanes over time and they gain the potential to become re-infected and pass the bacteria on to infants, who are at the greatest danger of serious complications. What is being done to curb the outbreaks? The CDC recommends vaccinating young children, but the message about booster shots for older children and adults is not. There is no question that as more people get vaccinated, there will be fewer cases. But with the current vaccine experts expect outbreaks like the ones we are seeing now in Washington State and elsewhere will continue. Scientists are now trying to develop a more effective, safer vaccine. What causes whooping cough? Whooping cough is an airway infection caused by the Bordetella pertussis bacteria that results in significant illness and risk of death in children, especially those younger than one year old. The World Health Organization estimates that there are 20 to 40 million cases of whooping cough in the world per year, with 90 percent of those cases occurring in developing countries. In 2010, there were 27,550 reported cases of pertussis in the United States, according to the Centers for Disease Control. What are the complications associated with whooping cough? Infants less than six months of age are at highest risk for developing severe complications from pertussis. Pneumonia, rib fracture or hernias from violent coughing, seizures, and fainting can all arise from whooping cough. Because infants have less developed immune systems, these complications from pertussis can be life-threatening. How is whooping cough spread? Whooping cough is spread through droplets in the air during coughing or sneezing. The bacteria is breathed in through the nose and then travels throughout the airways. This disease is highly contagious. What are the symptoms of whooping cough? The word "pertussis" means "violent cough," and that is the most striking symptom of this infection. The uncontrollable coughing spasms produce a distinctive "whooping" sound when patients try to breathe, and can lead to vomiting, loss of consciousness, and choking. Whooping cough begins with symptoms similar to the common cold - fever and runny nose. About a week later, patients start experiencing deep and violent coughing spells that make it hard to breathe. This cough usually lasts one to six weeks, but may persist up to 10 weeks. Click here to hear what whooping cough sounds like. How do I protect myself against whooping cough? The DTaP vaccine is a recommended childhood immunization that is given to children at 2 months, 4 months, 6 months, 15-18 months, and 4-6 years. The vaccine combination not only protects against whooping cough but also diphtheria and tetanus, which are other bacterial infections with severe health risks for patients. Because immunity against this bug goes down over time, booster shots are recommended in people ages 11-64. For more information visit the CDC's website. What do I do if I have it? Treatment includes antibiotics such as erythromycin if the infection is caught early enough. Babies with whooping cough are usually treated in the hospital because they are at higher risk for severe complications. To prevent yourself from spreading whooping cough to others, wear a face mask or cover your mouth when coughing. Do not go near babies and young children because they are very susceptible to the disease. Make sure everyone in your household is vaccinated and protected against pertussis. For more information, visit: NIH: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002528/ CDC: http://www.cdc.gov/pertussis/