Alaska Fights Persistent Infectious Diseases
Combating Alaska’s disproportionately high STD rates are a big focus of the state’s epidemiologists. But the state is struggling with other persistent infectious diseases. A new report from the state sheds gives a look at the status of a few diseases.
Tuberculosis continues to be an extremely stubborn disease in the western part of the state. 66 cases of TB were reported last year, with the annual incidence of 9 cases per 100,000 statewide; that almost 3 times the national rate.
Michael Cooper is the Infectious Disease Program Director for the state’s epidemiology program. He says challenges to fighting TB come from the state’s rural nature and limited healthcare infrastructure. But it’s also history that keeps TB in the state.
"Maybe most importantly is this incredible history of TB we have in Alaska. We had probably some of the highest rates seen anywhere in the world ever, not more than 60 and 70 years ago. There was great progress made 50, 40 years ago, but it leaves a big pool of people who have a sort of quiet TB infection, latent TB, where they feel fine and they may very well never get active TB where they can spread it. But they have a 5 to 10 percent chance of becoming active at some point in their life. When they do, that's when they can spread it to people around them So it's a real challenge," said Cooper.
The southwest portion of the state, including the YK Delta and Bristol Bay had a per capita incidence of 7 times the statewide average last year. The report shows that the disease affects Alaska Natives and people with Asian and Pacific Islander heritage at a disproportionately high rate.
The state’s also keeping an eye on a dangerous form of influenza that’s on the rise, haemophilus influenzae invasive disease. Thanks to a vaccine introduced in 1991, healthcare providers have all but eliminated one strain of the bacteria.
"When a vaccine came out with very good uptake, especially across rural Alaska, HiB numbers went way down. But corresponding to that, we've had in increase in invasive cases of another sero group, haemophilus influenzae A. We've actually had an increase, which you can't see in the report, but the B numbers are much lower than they were years ago, while the A numbers have crept up," said Cooper.
No vaccine is available for the A form. Cooper says it tends to be most damaging for young people.
"Serious long term consequences, kids with permanent nuerologic damage, long term sequelae which will never reverse: meningitis, seizures, kids that are hospitalized right now from outcomes related to their Haemophilus A disease. The same with Haemophilus B, we just aren't seeing as many cases fortunately in kids. Especially with children with these invasive types of Haemophilus, we see frequently severe outcomes, occasional deaths," said Cooper.
There have been 113 cases of Haemophilus influenza over the past five years, including 15 in 2012. The state works closely with the CDC's Arctic Investigations program on the disease.