There was good news Monday on World TB Day: cases of the respiratory disease have reached an all-time low in California.
The state reported 2,170 tuberculosis cases in 2013, down slightly from the 2,189 cases in 2012.
But the reports were mixed for the central San Joaquin Valley.
Fresno County saw cases increase from 34 in 2012 to 39 last year. Tulare County reported 12 cases in 2012 and 16 in 2013 and Kings County cases increased from five to six between the two years.
Madera and Merced counties had decreases. Madera cases dropped from 10 in 2012 to five last year; Merced cases dropped from 19 to 12.
Fresno County cases had been falling steadily in the past seven or eight years, said Dr. Kenneth Bird, interim public health officer and TB controller. The increase between 2012 and 2013 could be an indication that the number of cases is leveling off, he said.
The health department has reached out to high-risk populations for screening, including going to homeless shelters. Recently health workers began screening inmates in the Fresno County Jail, Bird said.
But five of the patients in 2013 were children younger than 15 and of those, two were younger than five years of age. This is worrisome, Bird said: "At that age, the disease can get very bad, very fast."
And when children are infected, it indicates "there are adults out there who are going longer with undiagnosed TB," he said. "They are going untreated and infectious longer."
Statewide, TB cases in children ages 4 and younger have increased from 48% to 59% between 2012 and 2013, the state Department of Public Health reported.
Tuberculosis is caused by bacteria spread through the air when a person coughs, sneezes or talks. People can be exposed to TB germs and have no symptoms and cannot spread the bacteria to others. They can remain infected with no disease for the rest of their lives, but in 5%-10% of cases, those infected progress to "active" disease, a serious, life-threatening illness that can be spread.
The concern remains that people seek care when they have TB symptoms -- a cough for more than two weeks, a fever, fatigue and weight loss, Bird said.
Doctors also need to assess patients to see if they are at risk of infection and offer TB tests, he said.
Merced County, which had a decrease in cases this past year, has seen a steady decline in cases since about 2000. But Dr. Timothy Livermore, the county's health officer, said more patients now have other health conditions, such as diabetes, that makes it harder to treat them for tuberculosis.
Diabetes affects the immune system, he said, and "it also seems it can be a problem with the absorption" of the drugs to treat TB.
According to the state Department of Public Health, 35% of adult cases had underlying medical problems in 2013 and diabetes was the most common.
An estimated 2.4 million Californians are infected with TB and are at risk of becoming sick in the future, the state said. California reports more cases than any state.
Source: California Department of Public Health