Bruno Project Rescue, Inc. v. Centers for Disease Control and Prevention

Opinion

United States Court of Appeals For the First Circuit

No. 25-1801

BRUNO PROJECT RESCUE INC., a 501(c)(3) corporation; ANNIE'S FAITH FOUNDATION, a 501(c)(3) corporation; CARIBBEAN CANINE CONNECTION CO., a 501(c)(3) corporation; ARUBA FLIGHT VOLUNTEERS INC., a 501(c)(3) corporation, d/b/a New Life for Paws Foundation; POTCAKE PLACE K9 RESCUE (USA) INC., a 501(c)(3) corporation; SAVE THE SATOS, a 501(c)(3) corporation,

Plaintiffs, Appellants,

v.

CENTERS FOR DISEASE CONTROL AND PREVENTION; UNITED STATES DEPARTMENT OF HEALTH AND HUMAN SERVICES; JIM O'NEILL, in the official capacity as Director of the Centers for Disease Control and Prevention,

Defendants, Appellees.

APPEAL FROM THE UNITED STATES DISTRICT COURT FOR THE DISTRICT OF MASSACHUSETTS

[Hon. Denise J. Casper, U.S. District Judge]

Before

Montecalvo, Lynch, and Dunlap, Circuit Judges.

Aaron M. Katz and Aaron Katz Law LLC for appellants.

Brian J. Springer, Attorney, Appellate Staff, Civil Division, United States Department of Justice, with whom Brett A. Shumate, Assistant Attorney General, Leah B. Foley, United States Attorney, and Thomas Pulham, Attorney, Appellate Staff, Civil Division, United States Department of Justice, were on brief, for appellees. July 13, 2026 DUNLAP, Circuit Judge. Plaintiffs-Appellants are

organizations that rescue stray puppies on Caribbean islands and

place the puppies with adoptive families in the United States.

Plaintiffs challenge a regulation issued by the Centers for Disease

Control and Prevention ("CDC"), an agency within the United States

Department of Health and Human Services. See Control of

Communicable Diseases; Foreign Quarantine: Importation of Dogs and

Cats, 89 Fed. Reg. 41726 (May 13, 2024) (codified at 42 C.F.R. pt.

71). The regulation requires that "[a]ll dogs presented for

admission into the United States must be at least six (6) months

old at the time of their arrival into the United States," and that

dogs not meeting this criterion "shall be denied admission and

returned to the country of departure." 42 C.F.R. § 71.51(f)

(2026). Plaintiffs claim that this age requirement -- as applied

to dogs imported into the United States from Caribbean

islands -- exceeds the CDC's authority under 42 U.S.C. § 264(a)

and is otherwise arbitrary and capricious under the Administrative

Procedure Act ("APA"), 5 U.S.C. § 706(2). The district court

granted the CDC summary judgment on Plaintiffs' claims. After

careful review, we discern no error in the district court's

judgment. We therefore affirm.

I.

The dog-maintained rabies virus variant (sometimes

referred to by the acronym "DMRVV," but which, for purposes of

- 3 - simplicity, we will refer to as "rabies") is a deadly infectious

disease that can be transmitted from an infected dog to any mammal

and, "once clinical signs appear, . . . is almost always fatal."

89 Fed. Reg. at 41726, 41754. "There is no treatment available

for persons ill with rabies." Id. at 41754. Although the United

States has been declared rabies-free since 2007, id. at 41726,

rabies remains a "serious public health threat in . . . more than

100 countries" and "kills approximately 59,000 people, mainly

children, per year globally from dog bites." Id. at 41754.

Addressing reintroduction of rabies is costly and difficult. Id.

at 41756–57. Thus, the CDC seeks to prevent reintroduction of

rabies into the United States -- as has happened before, in 1988.

See id. at 41754; see also id. at 41756–57.

The United States has regulated the import of dogs into

the United States and has imposed rabies vaccine requirements since

at least 1956. See Revision of Chapter, 21 Fed. Reg. 9805, 9879

(Dec. 12, 1956). As updated in 1985, see Foreign Quarantine, 50

Fed. Reg. 1516 (Jan. 11, 1985), the relevant regulation established

that -- except for certain dogs that were admitted into the country

for research purposes, were under six months old and had never

been in a country with rabies, or were at least six months old and

had not been in a country with rabies in the past six months -- a

dog could not enter the United States without a "valid rabies

vaccination certificate" that showed that the dog had been

- 4 - vaccinated when the dog was at least three months old and at least

thirty days before arrival at the port of entry. 42 C.F.R.

§ 71.51(a), (c) (1985).

Regulations of dog importations have changed over the

years. In 2021, the CDC temporarily suspended dog imports from

countries that the CDC designated as rabies high-risk countries on

account of rabid dogs with fraudulent paperwork entering the United

States from those countries. See Temporary Suspension of Dogs

Entering the United States From High-Risk Rabies Countries,

86 Fed. Reg. 32041 (June 16, 2021).

At issue in this case, the CDC again revised its dog

import regulations through notice-and-comment rulemaking in 2024,

allowing its temporary suspension of dog imports from rabies

high-risk countries to expire and requiring, among other things,

that all dogs "arriving in the United States be at least six months

of age."1 89 Fed. Reg. at 41727, 41738. The regulation's stated

1 The CDC also required that all dogs arriving in the United States be microchipped and that all dog importers submit a CDC dog import form for each dog imported to help officials verify that the dogs presented for admission are the same dogs identified in their accompanying documentation. Control of Communicable Diseases; Foreign Quarantine: Importation of Dogs and Cats, 89 Fed. Reg. 41726, 41727–28 (May 13, 2024) (codified at 42 C.F.R. pt. 71). For dogs imported from countries designated as rabies high-risk countries, the CDC required that importers "submit a standardized vaccination form verifying the rabies vaccination status of the dog." Id. at 41728. If the dogs imported from rabies high-risk countries were not vaccinated in the United States, the CDC also required that importers must "have their dog(s) undergo a veterinary exam and revaccination with a

- 5 - purpose was to "prevent the reintroduction and spread of" rabies

and to "prevent and deter the importation of dogs with falsified

or fraudulent rabies vaccine documentation." Id. at 41726. The

CDC determined that the regulation helps confirm that the dog is

old enough to have had an effective vaccine, because a dog's age

is most easily assessed after six months, as a dog has lost its

baby teeth by that time. Id. at 41765–66. According to the CDC,

the age requirement helps officials determine that "the dog

presented matches the documentation presented, particularly the

age listed for the dog, and that the dog is old enough to have

been adequately vaccinated for rabies." Id. at 41766. Further,

the CDC observed that the age requirement would "align[] with USDA

importation rules, ease[] enforcement of the vaccination

requirements, and reduce[] opportunities for fraud." Id.

Finally, the CDC determined that screening for rabies is easier

after six months due to the difficulty at younger ages of

distinguishing between uncoordinated movements that are simply

part of normal puppy behavior and those that are due to rabies.

Id.

USDA-licensed rabies vaccine at [a] CDC-registered [animal care facility]" and must either "obtain a rabies serologic test from a CDC-approved laboratory for their foreign-vaccinated dogs demonstrating adequate titer levels" or "have their dog remain under quarantine at the facility for 28 days after revaccination or until confirmation of adequate rabies serologic test from a CDC-approved laboratory is obtained, whichever occurs first." Id. at 41728–29.

- 6 - This age requirement substantially affects Plaintiffs'

dog-rescue efforts in the Caribbean islands, as Plaintiffs assert

that they have been harmed because they now have to care for

rescued puppies on the islands until the puppies reach six months

old and that fewer people in the United States want to adopt

six-month-old dogs (causing Plaintiffs to experience difficulty

fundraising for their rescue efforts). Accordingly, Plaintiffs

brought this lawsuit under the APA, alleging that the age

requirement exceeds the CDC's statutory authority and is otherwise

arbitrary and capricious. After the parties cross-moved for

summary judgment, the district court granted judgment to the CDC.

The court reasoned that the age requirement is within the CDC's

statutory authority because it facilitates reliable inspections of

imported dogs. Further, the court reasoned that in promulgating

the age requirement, the CDC duly considered the relevant issues

and reasonably explained its decision. Plaintiffs now appeal from

the district court's judgment.

II.

We review the district court's decision granting summary

judgment de novo. Littlefield v. U.S. Dep't of the Interior, 85

F.4th 635, 643 (1st Cir. 2023). Instead of the usual Federal Rule

of Civil Procedure 56 standard, however, the summary judgment

"rubric . . . has a special twist in the administrative law

context." Int'l Junior Coll. of Bus. & Tech., Inc. v. Duncan, 802

- 7 - F.3d 99, 106 (1st Cir. 2015) (quoting Associated Fisheries of Me.,

Inc. v. Daley, 127 F.3d 104, 109 (1st Cir. 1997)). Under the APA,

we "hold unlawful and set aside agency action, findings, and

conclusions found to be . . . (A) arbitrary, capricious, an abuse

of discretion, or otherwise not in accordance with law . . . [or]

(C) in excess of statutory jurisdiction, authority, or

limitations, or short of statutory right." 5 U.S.C. § 706(2).

"Because the APA standard affords great deference to agency

decisionmaking and because the Secretary's action is presumed

valid, judicial review, even at the summary judgment stage, is

narrow." Littlefield, 85 F.4th at 643 (quoting Visiting Nurse

Ass'n Gregoria Auffant, Inc. v. Thompson, 447 F.3d 68, 72 (1st

Cir. 2006)).

That said, when we review whether an action was within

an agency's statutory authority, we "may not defer to an agency

interpretation of the law," Loper Bright Enters. v. Raimondo, 603

U.S. 369, 413 (2024), but "must exercise [our] independent judgment

in deciding whether an agency has acted within its statutory

authority, as the APA requires," id. at 412. Because the

"judiciary is the final authority on issues of statutory

construction," id. at 401 (quoting Chevron, U.S.A., Inc. v. Nat.

Res. Def. Council, Inc., 467 U.S. 837, 843 n.9 (1984), overruled

by, Loper Bright, 603 U.S. 369), we have an "obligation to

independently interpret the statute . . . us[ing] every tool at

- 8 - [our] disposal to determine the best reading of the statute," id.

at 400. We are to "interpret statutes, no matter the context,

based on the traditional tools of statutory construction." Id.

at 403.

When we review whether an agency action is arbitrary or

capricious, however, we are "not to substitute [our] judgment for

that of the agency" and we only evaluate whether it was "based on

a consideration of the relevant factors and whether there has been

a clear error of judgment." DHS v. Regents of the Univ. of Cal.,

591 U.S. 1, 16 (2020) (first quoting FCC v. Fox Television

Stations, Inc., 556 U.S. 502, 513 (2009); and then quoting Citizens

to Pres. Overton Park, Inc. v. Volpe, 401 U.S. 402, 416 (1971)).

This standard of review is "highly deferential," and we will

"uphold an agency determination if it is 'supported by any rational

view of the record.'" Littlefield, 85 F.4th at 643 (quoting

Marasco & Nesselbush, LLP v. Collins, 6 F.4th 150, 172 (1st Cir.

2021)).

A. Statutory Authority

Plaintiffs' first argument on appeal is that the age

requirement as applied to dogs imported from the Caribbean islands

exceeds the CDC's statutory authority under 42 U.S.C. § 264(a).

The CDC relied on § 264(a) for the legal authority to impose the

age requirement challenged here. 89 Fed. Reg. at 41737. That

section states in relevant part:

- 9 - The Surgeon General, with the approval of the Secretary, is authorized to make and enforce such regulations as in his judgment are necessary to prevent the introduction, transmission, or spread of communicable diseases from foreign countries into the States or possessions . . . . For purposes of carrying out and enforcing such regulations, the Surgeon General may provide for such inspection, fumigation, disinfection, sanitation, pest extermination, destruction of animals or articles found to be so infected or contaminated as to be sources of dangerous infection to human beings, and other measures, as in his judgment may be necessary.

42 U.S.C. § 264(a) (emphases added).2 The Supreme Court has noted

that "[r]egulations under this authority have generally been

limited to quarantining infected individuals and prohibiting the

import or sale of animals known to transmit disease." Ala. Ass'n

of Realtors v. HHS, 594 U.S. 758, 761 (2021) (citing Ban on Sale

and Distribution of Small Turtles, 40 Fed. Reg. 22543 (May 23,

1975) (banning sale of small turtles to prevent the spread of

salmonella)); see, e.g., Control of Communicable Diseases;

Restrictions on African Rodents, Prairie Dogs, and Certain Other

Animals, 68 Fed. Reg. 62353 (Nov. 4, 2003) (restricting imports

and sales of certain animals to prevent the spread of monkeypox).

In Alabama Association of Realtors, the Supreme Court

held that § 264(a) likely did not authorize the CDC to extend a

2 The Surgeon General's authority has been delegated to the CDC. See 42 C.F.R. § 70.2 (2026).

- 10 - residential eviction moratorium in order to prevent the spread of

COVID-19. 594 U.S. at 763–64. The Court stated that the

authority granted in the first sentence of § 264(a) -- making and

enforcing regulations as "necessary to prevent the introduction,

transmission, or spread of communicable diseases" -- is informed

by the second sentence of § 264(a). Id. at 763. The second

sentence "informs the grant of authority by illustrating the kinds

of measures that could be necessary: inspection, fumigation,

disinfection, sanitation, pest extermination, and destruction of

contaminated animals and articles. These measures directly relate

to preventing the interstate spread of disease by identifying,

isolating, and destroying the disease itself." Id. Applying the

text of § 264(a) to the eviction moratorium, the Court noted that

there was a far more indirect, downstream connection between

evicting tenants and the interstate spread of disease than "the

direct targeting of disease that characterizes the measures

identified in the statute. Reading both sentences together,

rather than the first in isolation," the Court concluded that it

was a "stretch" to read § 264(a) as granting the CDC "authority to

impose th[e] eviction moratorium." Id. at 764.

Alabama Association of Realtors instructs that we must

review the age restriction at issue here to determine whether it

is consistent with the kinds of illustrative measures listed in

the second sentence of § 264(a) and whether it directly relates to

- 11 - preventing the introduction, transmission, or spread of

communicable diseases. We conclude that the age restriction is

not only consistent with the types of measures described in

§ 264(a), but is in fact one of the enumerated measures set out in

that section: The age requirement is an "inspection" measure.

Additionally, we conclude that such measure directly relates to

preventing the introduction of rabies into the United States.

The edition of Black's Law Dictionary that was current

in 1944, when § 264(a) was first enacted, defined "inspection" as

"more than perusal, . . . a critical examination, close or careful

scrutiny, a strict or prying examination, or an investigation."

Inspection, Black's Law Dictionary (3d ed. 1933); see also

Inspection, Funk & Wagnalls New Standard Dictionary (1943) ("The

act or process of looking into; especially, a careful critical

investigation or scrutiny."); Inspection, Webster's New

International Dictionary (2d ed. 1934) ("Act or process of

inspecting; a strict or prying examination."). The definition of

inspection's root word, "inspect," was "[t]o look, to view or

oversee for the purpose of ascertaining the quality or condition

of the thing." Inspect, Black's Law Dictionary (3d ed. 1933); see

also Inspect, Funk & Wagnalls New Standard Dictionary (1943) ("To

examine carefully or critically; investigate and test

officially."); Inspect, Webster's New International Dictionary (2d

ed. 1934) ("To look upon; to view closely and critically, esp. so

- 12 - as to ascertain quality or state, to detect errors, etc.; to

scrutinize.").

Under these definitions, the CDC's age requirement

qualifies as an inspection measure that allows officials "to

ascertain the quality or condition of the dogs." U.S. Sportsmen's

All. Found. v. CDC, 167 F.4th 813, 819 (6th Cir. 2026). It helps

officials conduct a "close or careful scrutiny" or "prying

examination" of imported dogs to ascertain their condition or state

by making screening for rabies easier. Although "puppies are

susceptible to rabies," it can be difficult to screen them for

rabies because it is hard to discern whether awkward movements are

due to rabies or normal puppy growth and development. See 89 Fed.

Reg. at 41766. The age requirement helps officials rule out young

age as a reason for any uncoordinated movement patterns that might

otherwise potentially signify rabies. Id. As the Sixth Circuit

has determined in another case involving a challenge to the same

regulation at issue here, "if the officials can rule out age as a

cause for the uncoordinated movements, then the officers can more

accurately ascertain the condition of the dog." U.S. Sportsmen's

All. Found., 167 F.4th at 819.

The age requirement also helps officials ascertain that

a "dog is old enough to have been adequately vaccinated for rabies"

because veterinarians can have difficulty determining "with

specificity whether a dog has reached the age at which it can be

- 13 - fully protected by the rabies vaccine before six months of age."

89 Fed. Reg. at 41765–66. "Many rabies vaccines are licensed for

use in dogs on or after 12 weeks of age," and laboratories have

suggested that it can take thirty days for the vaccine to become

effective. See id. at 41765. It takes time "to ensure the animal

has developed an adequate antibody response to vaccination." Id.

But "it is difficult to accurately assess the age of dogs that are

between four and six months old due to variability in an individual

dog's dental eruption patterns (loss of baby teeth)." Id. Once

a dog loses its baby teeth by six months old, veterinarians can

then inspect its teeth to accurately assess if it "has reached the

age at which it can be fully protected by the rabies vaccine."

Id. The age requirement is thus an inspection measure that

directly relates to preventing reintroduction of rabies into the

United States.

Plaintiffs object that the CDC's age requirement cannot

be characterized as facilitating an inspection for rabies because

any dog imported from countries that the United States has

recognized as rabies-free "will definitely not be infected with

rabies." This is incorrect for at least two reasons. First,

Plaintiffs fail to recognize that a dog imported from a country

recognized as "rabies-free" could still potentially have rabies

because rabies could have been reintroduced into that country but

not yet discovered. See, e.g., 89 Fed. Reg. at 41787 (citing

- 14 - Malaysia as an example of a country where, after having previously

been recognized as rabies-free, rabies was reintroduced in 2017

and where forty-five people died after having been infected with

rabies between 2017 and 2022). Second, a dog arriving from a

country recognized as "rabies-free" could still potentially have

rabies if the dog's importer brought the dog from a high-risk

country but stopped over in a rabies-free country and then

misrepresented the dog's country of origin at a U.S. port of entry.

See id. at 41766 (stating that the CDC has documented numerous

instances where dogs under six months old and from countries with

a high risk of rabies were routed to the United States through

rabies-free countries and then were fraudulently represented as

coming from rabies-free countries of origin). Thus, puppies

arriving from countries recognized as rabies-free still pose a

risk of carrying rabies.

In response to the CDC's fraud-prevention rationale,

Plaintiffs argue that the age requirement is unnecessary to

determine that an imported dog matches its documentation because

the regulation also imposes a requirement that all dogs be

microchipped in order to enter the country. See id. at 41727.

This argument does not get Plaintiffs very far. Even assuming

arguendo that the age requirement does not help officials assess

whether a dog matches its proffered documentation, the age

requirement still helps officials screen dogs for rabies and

- 15 - ascertain whether they are old enough to have been adequately

vaccinated against rabies. Further, where "[t]he importation of

just one dog infected with [rabies] risks reintroduction of the

virus into the United States, which could result in loss of human

and animal life and substantial public health response costs," id.

at 41736, nothing prevents the CDC from using a belt-and-suspenders

approach to ensure that the dog presented at a port of entry is

the same dog described in its documentation. The CDC retains

substantial discretion on what measures are necessary to prevent

the reintroduction of rabies into the United States; Congress has

directed that whether a measure is "necessary" to prevent the

introduction of rabies into the United States is a "judgment"

committed to the CDC. See 42 U.S.C. § 264(a).

We also reject Plaintiffs' argument that the age

requirement is effectively a prophylactic import prohibition of a

broadly defined class (dogs that are less than six months old)

that, under 42 U.S.C. § 265, must be accompanied by

country-specific findings that there is a "serious danger" of dogs

from that country having rabies. Section 265 allows the

CDC -- upon making a determination that "there is serious danger

of the introduction of" any communicable disease from a foreign

country and that this danger "is so increased by the introduction

of persons or property from such country that a suspension of the

right to introduce such persons and property is required in the

- 16 - interest of the public health" -- to prohibit "the introduction of

persons and property from such countries or places as [it] shall

designate in order to avert such danger." 42 U.S.C. § 265. The

age requirement, however, is not an import prohibition. It does

not prohibit the importation of dogs; rather, it is merely a

condition of entry for all dogs being imported. Once puppies are

six months old, if they meet all other conditions of entry, they

are allowed entry. Because the age requirement is properly viewed

as a measure enacted under § 264(a), not a prohibition on the

importation of dogs enacted under § 265, the CDC was not obligated

to make country-specific findings concerning rabies risk to adopt

the age requirement.

Our reading of the age requirement as a condition of

entry does not render § 265 superfluous. It is true that § 264(a)

and § 265 both authorize the CDC to take preventative measures

against the introduction of communicable disease. But "we

approach federal statutes touching on the same topic with a 'strong

presumption' they can coexist harmoniously." Dep't of Agric.

Rural Dev. Rural Hous. Serv. v. Kirtz, 601 U.S. 42, 63 (2024)

(quoting Epic Sys. Corp. v. Lewis, 584 U.S. 497, 510 (2018)). And

here, each provision has effect in distinct cases. See J.E.M. Ag

Supply, Inc. v. Pioneer Hi-Bred Int'l, Inc., 534 U.S. 124, 144

(2001) ("[T]his Court has not hesitated to give effect to two

statutes that overlap, so long as each reaches some distinct

- 17 - cases."). Section 264(a) authorizes the CDC to enact measures

that identify or isolate infected animals to prevent the

introduction or spread of a communicable disease, without regard

to whether the communicable disease is known to exist in the

animal's country of origin. By contrast, § 265 gives the CDC the

power to ban the entry of animals from a foreign country where a

communicable disease exists, regardless of whether any specific

animals are infected. Thus, a dog could be barred from entry

under § 264(a) because it failed disease-prevention-related

inspection requirements, even if its country of origin was

classified as rabies-free; and a dog could be independently barred

from entry under § 265 due to the existence of rabies in its

country of origin, even if the dog could otherwise pass all

disease-prevention-related inspection requirements. "Where two

laws are merely complementary -- as is undisputedly the case

here -- our duty lies not in preferring one over another but in

giving effect to both." Kirtz, 601 U.S. at 63.

B. Arbitrary and Capricious Review

Plaintiffs also argue that the age requirement as

applied to dogs imported from Caribbean islands is arbitrary and

capricious under the APA. Arbitrary and capricious review "simply

ensures that the agency has acted within a zone of reasonableness

and, in particular, has reasonably considered the relevant issues

and reasonably explained the decision." FCC v. Prometheus Radio

- 18 - Project, 592 U.S. 414, 423 (2021). Although "we must conduct a

searching examination to ensure that the agency's decision is

reasonably supported by the administrative record," we will -- in

our "highly deferential" review -- "uphold an agency determination

if it is 'supported by any rational view of the record.'"

Littlefield, 85 F.4th at 643 (quoting Marasco & Nesselbush, LLP,

6 F.4th at 172).

[W]e will not vacate an agency's decision unless it "has relied on factors which Congress had not intended it to consider, entirely failed to consider an important aspect of the problem, offered an explanation for its decision that runs counter to the evidence before the agency, or is so implausible that it could not be ascribed to a difference in view or the product of agency expertise."

Nat'l Ass'n of Home Builders v. Defs. of Wildlife, 551 U.S. 644,

658 (2007) (quoting Motor Vehicle Mfrs. Ass'n of the U.S., Inc. v.

State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 43 (1983)).

Ultimately, an agency simply needs to articulate a "rational

connection between the facts found and the choice made." State

Farm, 463 U.S. at 43 (quoting Burlington Truck Lines v. United

States, 371 U.S. 156, 168 (1962)).

In its final regulation, the CDC articulated several

reasons to support its decision to impose the six-month age

requirement. As already discussed, the CDC's primary rationale

was that the age requirement would better facilitate efforts to

- 19 - identify potentially rabid dogs at ports of entry and ensure the

effectiveness of rabies vaccinations. See 89 Fed. Reg. at 41765–

66. For the same reasons underlying our conclusion that the age

requirement facilitates inspection, we agree with the Sixth

Circuit that the "age requirement made it easier to spot

potentially rabid dogs before they enter the country and ensure

that rabies vaccinations were effective. It is reasonable for the

CDC to have drawn the conclusions it did on this record." U.S.

Sportsmen's All. Found., 167 F.4th at 822.3

Plaintiffs primarily attack the CDC's age requirement by

arguing that it is overbroad in that it applies to rabies-free

countries such as the Caribbean islands. An agency, however,

usually need not show that it has adopted the most narrowly

tailored option to address its concerns4; we are "not to ask whether

a regulatory decision is the best one possible or even whether it

is better than the alternatives." FERC v. Elec. Power Supply

3Some other reasons the CDC gave for the age requirement included the ability of dogs older than six months to better endure the "long travel times, temperature fluctuations, oxygen or altitude changes, and food/water deprivation" common in international transport, 89 Fed. Reg. at 41788–89, and the age requirement's alignment with the minimum six-month age requirement for dog imports for commercial purposes under USDA regulations, id. at 41766. These reasons provide additional rational support for the CDC's age requirement. 4 Of course, regulations must be narrowly tailored in certain

circumstances, such as when they impinge on First Amendment rights by effecting "[a] content- or speaker-based restriction on protected speech." Time Warner Cable Inc. v. FCC, 729 F.3d 137, 155 (2d Cir. 2013).

- 20 - Ass'n, 577 U.S. 260, 292 (2016). Inquiring instead whether the

agency's decision was rational, see State Farm, 463 U.S. at 43, we

conclude that it is. It is not irrational to conclude that

importers may attempt to transport dogs from high-risk countries

into the United States through countries in the Caribbean, given

their proximity to the United States. The CDC has identified

instances of fraud regarding dogs transported through other

rabies-free countries including Canada and Mexico, 89 Fed. Reg. at

41766, and it is a reasonable inference that individuals could do

the same through Caribbean nations. An agency is allowed to make

"a reasonable predictive judgment based on the evidence it had."

Prometheus Radio Project, 592 U.S. at 427. This is especially

true here, where § 264(a) gives the CDC authority to make

"regulations as in [its] judgment are necessary to prevent the

introduction . . . of communicable diseases from foreign

countries," 42 U.S.C. § 264(a), and where the CDC has noted the

extraordinary costs and difficulties of dealing with the

importation of just one dog with rabies -- not to mention the risk

to lives from such an event, 89 Fed. Reg. at 41754–57.5 In short,

Plaintiffs' reliance on National Fuel Gas Supply Corp. v. 5

FERC, 468 F.3d 831 (D.C. Cir. 2006), is misplaced. In that case, the D.C. Circuit held that the Federal Energy Regulatory Commission ("FERC") had not provided "evidence of a real problem" where FERC's order at issue did "not include a single example of abuse" by a certain class of entities; rather, any potential for abuse was merely theoretical. Id. at 841. By contrast, here, the analogous class of entities is rabies-free countries, and the CDC has

- 21 - it was "acceptable for the CDC to regulate across the global board

rather than target only high-risk areas." U.S. Sportsmen's All.

Found., 167 F.4th at 822.

Plaintiffs relatedly attack the CDC's regulation on the

basis that the CDC did not adequately explain how the age

requirement could prevent fraud. We disagree. The CDC noted that

it had been "document[ing] a marked increase in fraud committed by

importers of dogs from [rabies] high risk countries." 89 Fed.

Reg. at 41755 (citing numerous sources). The CDC observed that

"[m]ultiple international and U.S. investigations have identified

importations of puppies that were too young to meet rabies

vaccination requirements," and that "reports of . . . underage

dogs with fraudulent vaccination records have been documented in

the United States and abroad." Id. Specifically, the CDC

outlined several instances between 2015 and 2021 where rabid dogs

with falsified vaccination documentation were imported into the

United States from countries with a high risk of rabies, requiring

significant effort and expense to locate, treat, and monitor the

persons and animals with whom the rabid dogs had come into contact

while infectious. Id. at 41755–56. Further, the CDC noted that

documented examples of importers attempting to fraudulently transport dogs from high-risk countries into the United States through nearby rabies-free countries. Thus, the threat of fraudulent transfer of dogs through the Caribbean rabies-free countries is not simply theoretical, as was the threat of abuse in National Fuel.

- 22 - it had "documented many instances of young dogs under six months

of age being routed from [rabies] high-risk countries through

[rabies]-free countries, such as Canada or Mexico, to circumvent

U.S. entry requirements," and where the importers "made claims

that their dogs had not been in a [rabies] high-risk country."

Id. at 41766. It also stated that it had "documented several

instances of importers attempting to import an unvaccinated dog

using the vaccination paperwork for another dog." Id. at 41767.

Given the concerns raised by all these reports of fraud, it was

reasonable for the CDC to impose the age requirement for all

imported dogs, not just those coming directly from high-risk

countries. As the CDC stated, requiring all dogs to be at least

six months of age will allow the CDC to "better confirm that the

dog presented matches the documentation presented, particularly

the age listed for the dog." Id. at 41766.

Plaintiffs argue that the age requirement and other

measures imposed by the regulation at issue are not adequate to

solve the vaccination-paperwork fraud problem, seemingly implying

that the age requirement is underinclusive and thus irrational.

Although the age requirement may not be fully adequate to prevent

the reintroduction of rabies into the United States, that is beside

the point. "We know of no law that prohibits an agency from

attacking the evils within its jurisdiction in a piece-meal

fashion." BASF Wyandotte Corp. v. Costle, 598 F.2d 637, 663 n.53

- 23 - (1st Cir. 1979). That the age requirement rationally facilitates

identifying potentially rabid dogs at ports of entry, ensuring the

effectiveness of rabies vaccinations, and deterring fraud is

sufficient. The CDC's action did not need to solve all dog import

problems all at once. We further note that the age requirement

was not imposed in isolation. It was accompanied by other measures

that, taken together, likewise facilitate identifying potentially

rabid dogs, ensuring that imported dogs are adequately vaccinated

against rabies, and deterring fraud. See 89 Fed. Reg. at 41727–

29.

Finally, Plaintiffs' contention that the CDC overlooked

Plaintiffs' reliance interests fails as well. When an agency

changes its existing policies, it must recognize "that

longstanding policies may have 'engendered serious reliance

interests that must be taken into account.'" Regents, 591 U.S.

at 30 (quoting Encino Motorcars, LLC v. Navarro, 579 U.S. 211, 222

(2016)). "It would be arbitrary and capricious to ignore such

matters." Id. (quoting Fox Television Stations, 556 U.S. at 515).

Here, in imposing the six-month age requirement, the CDC acted

within the zone of reasonableness by considering the relevant

issues, including the interests of importers. Contrary to

Plaintiffs' argument, the CDC sufficiently accounted for

Plaintiffs' reliance interests in their dog rescue efforts in

rabies-free countries. After providing opportunity for and

- 24 - receiving public comments, the CDC stated that it was "provid[ing]

additional flexibility and less burden to importers without

compromising public health goals" by adopting a six-month age

requirement instead of a seven-month age requirement recommended

by some in the scientific community. 89 Fed. Reg. at 41765. The

CDC thus "reasonably considered the relevant issues and reasonably

explained the decision" in imposing the age requirement. See

Prometheus Radio Project, 592 U.S. at 423.

III.

For the foregoing reasons, the district court's judgment

is affirmed.

- 25 -