Contra Costa Health Services officials closed the school Friday because of the outbreak, but allowed it to reopen today to students, faculty and staff members who could prove that they were symptom-free and taking antibiotics, according to Contra Costa Health Services.
Public health nurses were at the school this morning screening students and staff members.
People who choose not to take antibiotics will not be allowed back to school for 21 days. If they remain symptom-free, they will be allowed back May 30, according to county health officials.
People with symptoms of whooping cough, also known as pertussis, will not be allowed back to school until they have completed a five-day course of antibiotics.
The school, which is in an unincorporated part of the county, has about 300 students between kindergarten and 12th grade and at least half of the infected children are in kindergarten, according to health officials.
The East Bay Waldorf School reportedly has an unusually high number of children who are not vaccinated against the infection, health officials said. The vaccine, which is not mandatory under state law, would have prevented most children at the school from contracting the disease, Dr. Wendel Brunner, the county's health services public health director, said.
Once thought to have been virtually wiped out in the United States, cases of whooping cough have been on the rise in California, in part because some people fear that the vaccine can cause seizures, attention deficit hyperactivity disorder and autism.
According to health officials, however, studies have found no connection between the vaccine and serious health complications.
Whooping cough, which gets its name from the characteristic gasping sound of a person fighting for breath while coughing, is spread through the air when someone coughs or sneezes, or by other close contact. The disease can be fatal in infants and can last for months in children and adults.
Other complications of the infection include vomiting, pneumonia, seizures and brain damage.
People who have symptoms of the illness are urged to get treated and not to attend public events.