In mainstream society, the word “outbreak” is often associated with epidemiological emergencies of Hollywood disaster-movie proportions.
But in the real life world of public health, the term often plays out in a tamer fashion, says Dr. Jonathan Fielding, director of Los Angeles County Department of Public Health.
"Outbreak," says Fielding, essentially means a greater number of cases of a particular illness than would normally be expected in a defined geographic region or time period.
The California Department of Public Health (CDPH) seconds that definition.
"'Outbreak' means the occurrence of cases of a disease (illness) above the expected or baseline level," Ralph Montano, spokesman for the CDPH, wrote in an email response to questions from KPCC. "Usually over a given period of time, in a geographic area or facility, or in a specific population group."
The term grabbed headlines in recent days when L.A. County health officials confirmed that an outbreak of tuberculosis (TB) is happening among the homeless population living in downtown’s Skid Row community.
But, says Fielding, this outbreak is not of the high-drama variety nor is it anything new to the area.
“We’ve known there was a problem since 2007,” he says, adding that it's "not unusual to have higher TB (rates) in homeless population."
But the particular strain of TB involved in this outbreak only became known to local health officials six years ago, he says, thanks to their ability at that time to begin genotyping TB strains.
Coupled with epidemiological data gathered by health workers, genotyping is key to helping scientists trace and track those who may be infected with the disease.
"We now have a number of cases with same genotype that totals about 80 cases," says Fielding. Those cases are concentrated mostly in the downtown Skid Row area.
That tally is expected to climb as federal health officials this week join state and county public health scientists in collecting and compiling more epidemiological data in the Skid Row neighborhood.
Fielding confirmed Friday that his agency asked the CDC for assistance "about a couple months ago."
As a result, he says, eight CDC employees are scheduled to arrive in Los Angeles today to help county health workers who’ve already been receiving assistance from the CDPH’s Tuberculosis Control Branch.
Together, the health officers from all three branches will collect and sort epidemiological data in an effort to identify and treat residents of Skid Row who may be infected, says Fielding. The data will also be used to create a more robust TB screening and prevention computer data system for use by homeless shelters and skid row health providers.
"Basically we’re doing a lot of statistical analysis and getting a lot of hands on the problem at the same time," he says. "Trying to develop this unified data base is quite intensive work and we’re very happy to have the collaboration."
TB is a bacterial infection of the lungs that can be spread through the air when an infected person coughs or sneezes. TB is less infectious than the viruses that cause the flu or the common cold, and it can’t be spread by touching an infected person or by sharing food and drink with them, the CDC says.
TB Symptoms include the coughing up of blood or sputum, chills, weakness and weight loss.
Known also as "consumption," the disease was nearly eradicated in the U.S. but experienced a resurgence in the mid-1980s, the CDC reports.
Since then, the U.S. reports thousands of cases each year. In California, CDPH logged 2,325 cases of TB in 2011, down from 2,329 in 2010, Montano says.