How important is quarantine?

New birds, even seemingly healthy ones, can carry diseases. If a bird has a latent disease, the stress of moving to a new home can trigger the onset of symptoms which were not visible before.

Quarantine gives you time: time for diseases that have lain dormant to spring up, and time for you to observe the birds for any subtle signs of illness.

Ducks are very hardy and have a high resistance to infectious diseases. They are much less susceptible to disease than chickens and most other landfowl. They are not susceptible to Marek’s disease or infectious coryza, two diseases which are a major concern in chickens. Hence, quarantine is perhaps of less importance in a duck flock than a chicken flock. Many people don’t quarantine new ducks. Realistically, the risk is quite low.

But not zero. One sick duck could kill your entire flock. Ducks (wild waterfowl, particularly) are one of the primary carriers of avian influenza, and can also carry, transmit, and succumb to multiple other deadly diseases. If you have chickens, ducks can transmit diseases to your chickens even if they are not affected themselves.

Adhering to basic biosecurity practices and quarantining all new birds can save you a lot of potential heartache—or even the loss of your whole flock.

IT HAPPENS

In November 2024, Susie’s Duck Rescue in Hawaii, a nonprofit duck rescue with around 70 Muscovy ducks, was struck by avian flu. Susie’s birds suddenly started getting sick and dying. And although some began to recover, when she sent a dead bird to be tested by state officials, they confirmed it was avian flu. The Department of Agriculture then euthanized her entire flock. Avian flu affects backyard flocks and commercial flocks alike—and ducks are not exempt.

More recently, another poultry keeper I know lost her entire flock. She brought in some new chickens, and before long, all her birds—ducks, chickens, geese, everything—were getting sick and dying.

Here’s a quote from “KaleIAm” on Backyard Chickens:

I got rescue ducks that were abandoned on a pond and lived with wild mallards. They looked fine. They actually had infectious bronchitis, probably brought parasites that now live in my soil, and made my original ducks ill. I wish I had taken them to the vet before introducing them to my flock to test for parasites and viruses, instead of after when everyone got sick. I’m not saying you shouldn’t rescue. Rescuing is a wonderful thing. I just rushed things and I wish I hadn’t endangered my original birds.

KaleIAm

Here’s another story:

https://www.backyardchickens.com/threads/talk-me-though-deciding-to-cull-a-flock-infectious-bronchitis.1455699/

In this thread, poultry keepers share their stories about buying new birds and bringing in worms, coccidiosis, lice, mycoplasma, other respiratory diseases, and more:

https://www.backyardchickens.com/threads/lets-talk-about-why-you-should-quarantine-new-birds.1634558/page-2

Another one:

https://www.backyardchickens.com/threads/i%E2%80%99m-so-depressed-i-think-i-brought-pasteurella-fowl-cholera-into-my-flock.1317307/

And here’s another person who lost her flock to avian influenza:

https://www.backyardchickens.com/threads/what-i-learned-from-my-awful-experience-with-avian-flu.1532060/

It’s real. It happens. You too could be affected. Quarantine is one of the best measures you can take to avoid a tragedy.

Photo credit: “Very sick girl” (CC BY-NC-ND 2.0) by tifotter

Diseases you risk bringing in

(This isn’t an exhaustive list, and the “risk level” rating isn’t necessarily factual, but based on my own conjectures.)

7 steps for successful quarantine

Diseases can be transmitted through contaminated food, water, dirt, bedding, feathers, feces, aerosols, and “fomites” (objects such as shoes, clothing, and tools). Proper quarantine, unfortunately, isn’t as easy as “ a separate pen.”

If you don’t have the ability to do proper quarantine, penning new birds separately is better than nothing, but it won’t prevent the spread of all diseases.

Here’s how to do it properly:

1. The quarantine area should be at least 30 feet (10 meters) away from any other birds, and ideally downwind and downhill. Farther away is better. Some sources recommend 100 feet away. A separate building, such as a garage or even your house, is also an option.
2. To prevent cross-contamination, use separate feed and water dishes, as well as separate shovels or anything else you might use in the quarantine area. If it enters the quarantine pen, it shouldn’t go into your main flock without being disinfected.
3. Don’t wear the same shoes into the quarantine area as you do into your other birds’ area. Visit the quarantine area last, after you’ve finished caring for your other birds. A disinfecting foot bath is another option.
4. New birds could be a carriers of something they are immune to and show no signs of, but that your flock has no immunity against. For example, ducks can carry Newcastle disease and avian influenza without symptoms. Mycoplasma is a particular danger—birds who have had it and recovered will still be carriers for life. “Lifelong carriers” or “silent shedders” are asymptomatic, but they can still spread the disease. To combat this possibility, I recommend, if you can, introducing a potentially sacrificial “canary” bird from your flock to the quarantine area. House it with or next to the quarantined birds. If the “canary” doesn’t get sick after the quarantine period, you’re probably safe. It’s also possible for your birds to be immune to something the new birds are not immune to, in which case it’s possible the “canary” will remain healthy while the new birds get sick.
5. If you bring in new ducks from more than one source, they should be quarantined separately.
6. During quarantine, consider deworming the new birds, or at doing a fecal float test to check for internal parasites. Do NOT give the new birds antibiotics. Not only is antibiotic overuse a major problem, but you also don’t want to mask symptoms of disease; you want to know if there are symptoms.
7. After quarantine, wash and clean the quarantine area and the things in it, and disinfect it if possible.

Here are our new ducks quarantined in a pen far from the rest of our flock (several hundred feet away, in fact!).

How long should the quarantine period be?

Four weeks is the recommended time.

There’s no point in quarantine if you don’t fulfill the recommended time, because some diseases take some time to become noticeable or cause symptoms. Most notably, mycoplasma gallisepticum has an incubation period of 7-21 days.

The incubation period for avian influenza is 1-14 days. Most other diseases will show symptoms in less than two weeks, so if you feel you can’t wait and are willing to take the risk, two weeks is the minimum time for quarantine.

Some sources say six weeks is preferable. I think this is more applicable to chickens, because they are susceptible to Marek’s disease while ducks aren’t. Marek’s disease is the only worrisome disease, to the best of my knowledge, with a possible six-week incubation period (it’s 4-6 weeks).

At the end of 30 days, do a thorough examination of the duck or ducks in quarantine. If you see any signs of unwellness, don’t introduce them to the flock. Hopefully, however, all will go well, and the new birds can be introduced to the rest of your flock!

Biosecurity

Putting basic biosecurity practices into place can go a long way toward keeping your flock safe and healthy.

1. Keep a closed flock. This means not introducing any new birds from external sources and hatching your own ducklings instead. If you want to have a closed flock but want to breed regularly, be sure you start with enough genetic material to avoid/minimize inbreeding.

2. If you don’t want to keep a totally closed flock, the safest way to bring in new birds is by buying ducklings from a reputable hatchery. There is little to no risk in buying day-old ducklings from an NPIP-certified hatchery. Ducklings sold in TSC or other feed stores are usually from large hatcheries. Hatching eggs are also generally safe, but some diseases can be transmitted vertically through eggs—including mycoplasma gallisepticum (MG).

3. Avoiding poultry shows, auctions, and swaps is a good idea.

4. If you bring your birds to a show or expose them to other birds, quarantine them when you bring them home before reintroducing them to the rest of your flock. I know someone who brought his quail to an expo, and all of them died shortly thereafter.

5. Keep a separate pair of “farm” shoes or boots to wear around your duck yard or on the farm, and don’t wear them off your property, especially not to a feed store or another farm. Don’t wear “town/city” shoes into any place your ducks inhabit, especially if you’ve recently visited a feed store or suchlike.

6. Wild birds are one of the major carriers of disease. Covering your run and trying to keep wild birds away from your coop/run may be a good idea.

7. Some people spray the bottom of their shoes with bleachwater after visiting any yard with chickens or other poultry, or use disinfecting foot baths.

Other good resources:

https://opensanctuary.org/establishing-a-safe-and-effective-quarantine-policy/

https://www.backyardchickens.com/articles/the-essential-quarantine-an-important-but-often-underestimated-part-of-raising-chickens.67097/

https://the-chicken-chick.com/quarantine-of-backyard-chickens-why-and/

Buying new birds

If you do buy adult or juvenile birds, or even ducklings from backyard breeders or non-hatchery sources, be careful. Don’t buy birds that look sick, or even unthrifty.

One major red flag is nasal and/or ocular discharge, sneezing, or audible or labored breathing. These are likely signs of respiratory disease. Many respiratory diseases are very contagious and can be difficult to get rid of and/or very deadly.

Here are some things to look for when buying birds:

1. Are their eyes and nostrils clear?
2. Do their feathers look clean, bright, and smooth?
3. Do they look active — moving around, making noise, and taking an interest in their surroundings?
4. Do they have a good appetite?
5. Are they limping? Even if they aren’t, I recommend each duck’s feet for bumblefoot before buying.

I disregarded this advice the first time I decided to buy new ducks and quarantine them. I bought seven ducks from someone who kept them in a very small, very dirty enclosure. They didn’t look very healthy. Their feathers were dull and ragged. I just hoped it was a result of their conditions rather than any contagious illness. At the time, I didn’t think of checking for bumblefoot. I quarantined them, and fortunately they were not carrying any diseases, but most of them did have bumblefoot.

Even if a bird looks healthy and even if you know where it came from, it should be quarantined in case it’s an asymptomatic carrier of something but still infectious.