infectious diseases
The Best Defense: Routine Public Health Testing
by Kim Krisberg, writer
Late last fall, China entered its fifth epidemic wave of H7N9 influenza, with nearly 600 cases as of
April. About 40 percent of people who become infected die as a result. The virus’s re-emergence has US
public health laboratories on alert.
I
n this case, however, that heightened awareness isn’t part of a larger
emergency response effort, like the ones public health workers are waging
against Zika virus. If H7N9 evolved into a strain that could easily pass
from person to person—a capability the virus does not currently have—public
health laboratories are prepared to quickly scale up their response systems.
Such a scenario makes clear the importance of well-funded public health
preparedness programs. But in its current form, what the H7N9 threat really
underscores is the critical nature of routine, everyday public health work—
work that typically goes unnoticed and unknown.
“Looking for the usual is where we find the unusual,” said Peter Shult, PhD,
interim laboratory director at the Wisconsin State Laboratory of Hygiene.
“We’re always monitoring for novel viruses. But in the final analysis, it’s about
routine surveillance—that’s the capacity and capability that we need to keep
well funded.”
I t’s critical that public health laboratories be on the
cutting edge of detecting new and emerging conditions
and diseases.
H7N9 has been on Wisconsin’s radar since it first emerged in China in 2013.
Since then, the World Health Organization has reported more than 1,300
human cases in China, with fifth wave case counts the highest so far. Evidence
suggests that most people become infected after contact with infected poultry
or contaminated environments, such as live poultry markets. There is no
evidence of sustained person-to-person transmission of the virus, but WHO
has reported signs of antiviral resistance. In Wisconsin, monitoring for H7N9 is
part of its routine surveillance of seasonal flu strains.
During flu season, Shult said the laboratory typically tests a few thousand flu
specimens, gathering data on which strains are in circulation and monitoring
for potential pandemic threats. If scientists are unable to subtype a specimen,
it indicates a potential novel strain such as H7N9 and further testing is
conducted. Wisconsin is also one of three National Influenza Surveillance
Reference Centers, which means it conducts additional, higher-level molecular
testing that informs the following year’s flu vaccine planning.
News of H7N9’s fifth wave didn’t trigger a surge in the laboratory’s activities,
Shult reported, though identifying a case in the US would be significant. He
noted that the laboratory has been doing year-round flu surveillance for a
while now, monitoring for travel-related flu strains and responding to novel
strains closer to home, such as the human cases of H3N2v flu, which arise
from swine contact, that were detected in Wisconsin in 2012.
Right now, Shult said the Wisconsin laboratory is prepared and capable of
confronting multiple outbreaks and threats. But the laboratory needs
adequate funding to sustain that capacity.
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LAB MATTERS Spring 2017
“For instance, if we had an outbreak of flu and vaccine-preventable disease, we
could handle that given current staffing and equipment,” he said. “But if I take
a hit in dollars, I’d say at that point, all bets are off.”
At the federal level, monies from the Affordable Care Act’s (ACA) Prevention
and Public Health Fund have become wholly entwined with the Centers for
Disease Control and Prevention’s (CDC) base budget and core activities.
Since the ACA’s enactment, the fund has invested $40 million
annually into CDC’s Epidemiology and Laboratory Capacity
(ELC) program, which funds all 50 state health
departments. Of particular importance, ACA ELC
funds are flexible—as opposed to disease-
specific—and that means laboratories can
use them to build, maintain and improve
all-hazards readiness.
On the ground in Wisconsin, for
example, the ELC helps fund 20
of 40 bench-level scientists in
the laboratory’s communicable
diseases division. If an
ACA repeal eliminated the
Prevention and Public Health
Fund, “it would cripple us,”
Shult said.
Victor Waddell, PhD,
MS, bureau chief of the
Arizona State Public Health
Laboratory, agreed: “The
(ACA) ELC funding has
become extremely important
to us.” In Arizona, the funds
support mosquito-borne
virus testing, equipment
maintenance, scaled-up
food-borne disease testing and,
of course, flu surveillance. The
Arizona laboratory conducts routine
seasonal flu testing, rapidly identifying
circulating flu strains, monitoring
for signs of antiviral resistance, and
forwarding rare specimens to CDC for further
testing.
isconsin is also one of three National
W
Influenza Surveillance Reference Centers, which means
it conducts additional, higher-level molecular testing that
informs the following year’s flu vaccine planning.
PublicHealthLabs
@APHL
APHL.org