Covetrus
|
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New World screwworm
treatment options for dogs
and cats
1
The potential re-emergence of the
New World screwworm (NWS,
Cochliomyia hominivorax), has
renewed regulatory and clinical focus
on prevention and treatment strategies
for this historically eradicated parasite.
NWS has been spreading northward
from Mexico toward the U.S. southern
border, prompting heightened
surveillance and preparedness efforts.
In response, the FDA's Center for
Veterinary Medicine (CVM) has outlined
treatment options for NWS myiasis
in animals. In late 2025, Elanco's
Credelio
®
Quattro-CA1 (lotilaner,
moxidectin, praziquantel, and pyrantel
chewable tablets) received FDA
conditional approval for the treatment
of NWS larval infestations in dogs.
Additionally, Credelio
®
(lotilaner) and
Credelio
®
CAT (lotilaner) chewable
tablets were granted FDA Emergency
Use Authorization for the treatment
of NWS infestations in dogs and
cats, respectively.
According to current regulations,
veterinarians may use these products
extra-label with a valid veterinarian-
client-patient relationship (VCPR),
providing defined therapeutic
options should NWS cases occur in
companion animals. If a case of NWS
is suspected, the veterinarian should
follow USDA Animal and Plant Health
Inspection Service (APHIS) protocols
for nationally reportable diseases.
Key Regulatory Actions,
Emerging Therapies,
and Clinical Innovations
Shaping Small
Animal Practices
I N D U S T R Y N E W S
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