Ever heard about fowl pox in chickens? Have you ever wondered if it’s contagious or fatal to your flock?
Fowl pox in chickens is a viral disease that is contagious and needs your immediate intervention. The avian pox virus causes it and can manifest as wet or dry.
Luckily, this is not a fast-spreading viral infection, but it’s still important for you to react quickly and potentially prevent the spread to all of your birds.
In this article, you’ll learn all there is to know about fowl pox in chickens, its symptoms, treatment, and prevention.
Fowl Pox in Chickens: An Overview
Mammals—including humans—are not susceptible to it. Fortunately, humans are not vulnerable to other types of avipoxviruses either.
It is usually contracted through abrasions (cuts or scrapes) in the skin. It’s especially common in areas with high mosquito populations since their bites carry the infection.
Fowl pox occurs in two forms: cutaneous (dry) and diphtheric (wet). I’ll expand on these more in the below sections.
Some chickens become naturally immune to it after contracting Fowl Pox; others can catch it repeatedly—especially when they are stressed or already have a weakened immune system.
Fowl Pox Explained
The fowlpox virus possesses a large genome, approximately 300 kilobases in length, consisting of linear double-stranded DNA. Each end of the genome features a hairpin loop.
This genetic material encodes over 200 genes, encompassing crucial elements such as DNA polymerase, NTPaseI, uracil glycosylase, and thymidine kinase.
The expression of these genes follows distinct temporal patterns categorized as immediate, early, and late.
Differences in genomic profiles are observed between field strains linked to outbreaks and vaccine strains.
These strains can be partially distinguished through methods like restriction endonuclease analysis, nucleotide analysis of specific genes, and immunoblotting.
However, it is molecular analyses of fowlpox virus strains from vaccines and those in natural settings that reveal significant distinctions.
Avipoxviruses exhibit intricate, multilayered virions. The capsid takes on a brick-shaped form, measuring approximately 330 × 280 × 200 nm.
It is enveloped by one or more membranes that enclose a biconcave core housing the genome within a nucleoprotein complex.
How Fowl Pox Spreads Between Chickens
Usually, pox spreads through direct contact with infected birds or contaminated surfaces.
This happens when birds share a coop, especially through food and water sources, foraging near contaminated feces, or sharing nesting boxes.
Feather debris, skin dander, pus, scabs, blood, and flaked-off pieces of skin are other ways that it transmits from chicken to chicken.
It can also spread by chickens pecking at one another’s eyes or beaks.
Once it is in a coop, it is difficult to stop the spread throughout the entire flock.
Knowing the symptoms, swiftly quarantining the affected chickens, and then immediately disinfecting the entire coop and run are the best ways to slow or stop the spread.
Dry Fowl Pox in Chickens (Cutaneous Form)
Dry Pox usually gives chickens dry, scaly lesions on unfeathered areas such as the comb, wattles, and legs.
Lesions may also appear in the mouth, pharynx, and trachea.
These lesions are white, grey, or black; they may look like cuts or raised and may be mistaken for blisters. These blisters will eventually grow, turn yellow, or look like dark scabs or warts.
After the chicken is cured of Fowl Pox, it will be left with scars where these warts or scabs once were.
Wet Fowl Pox in Chickens (Diphtheritic Form)
Wet Pox is uncomfortable and more deadly than dry pox.
It leaves your flock with yellowish lesions in the mucous membranes of the mouth, throat, and upper respiratory tract.
These lesions can lead to difficulty breathing and swallowing.
How to Prevent Fowl Pox in Chickens
Vaccinating chickens against fowl pox is a strong preventive measure.
Implementing strict biosecurity measures helps prevent the introduction and spread of the virus, too.
This includes controlling access to the flock and disinfecting equipment and facilities.
Infected birds should be quarantined or isolated from the rest of the flock to prevent further transmission.
This is not always successful because it spreads fast, but it’s low-effort and is absolutely worth a try.
Can You Vaccine for Fowl Pox in Chickens?
There is currently no specific and effective treatment for avian infections caused by the fowlpox virus.
For now, the primary emphasis lies in prevention, especially smart biosecurity measures and vaccinations.
In regions where fowlpox is more prevalent, it is recommended to vaccinate chickens and turkeys using a live-embryo- or cell-culture-propagated virus vaccine.
The most commonly utilized vaccines are live, attenuated strains of the fowlpox virus and the pigeonpox virus, known for their high immunogenicity and low pathogenicity.
In high-risk areas, a live, attenuated virus vaccine of cell-culture origin is often administered within the first few weeks after hatching, followed by revaccination at 12–16 weeks of age, which is typically adequate.
The timing of vaccinations is contingent on factors such as the health of the birds, the extent of exposure, and the nature of the operation.
Given the gradual spread of infection, administering vaccinations when fewer than 20% of the birds exhibit lesions can effectively limit the virus’ dissemination within affected flocks.
Remember that passive immunity might impede the replication of the vaccine virus.
Progeny from recently vaccinated or recently infected flocks should only be vaccinated once passive immunity has sufficiently declined.
A week after vaccination, those birds should be examined at the vaccination site for swelling and scab formation, referred to as “take.”
The absence of vaccine take may indicate insufficient vaccine potency, lingering passive or acquired immunity, or errors in the vaccination process.
In these cases, it’s wise to revaccinate with a different vaccine lot number.
Fowl Pox Vaccines
Here are some of the best available Fowl Pox vaccines available online. You can also get vaccines through your local veterinarian.
How to Treat Fowl Pox in Chickens
There isn’t a specific antiviral treatment for fowl pox in chickens; this is something they will have to work through naturally on their own.
However, supportive care and management practices can help affected birds recover and prevent the spread of the virus.
Here are some general guidelines to help you help your flock.
Isolation and Care
Immediately separate the affected chickens. This will prevent the spread and make it less likely that the entire flock will be affected.
Keep all birds (sick and healthy) at the most comfortable temperature possible.
This may mean supplementing heat or offering cooling stations (fans or even air-conditioning) to reduce stress and make it easier for their immune systems to fight off Fowl Pox naturally.
Food and Water
Offer good, easily accessible nutrition. Offer easily digestible and nutritious food to infected birds.
Even if your flock typically prefers foraging, give them feed in their coop or run to make it easier for them.
This helps maintain their strength and aids in the recovery process.
Always have clean and fresh water available.
Yes, chickens are notorious for making a mess of their water, especially if you offer their water in an open bowl or bucket.
Now is the time to empty and rinse the bucket at least once a day.
This makes the water more enticing and allows their immune systems better chances of recovering.
Lesion and Scabs
Do NOT pick at the lesions or scabs.
I know it’s easy to want to pull those off, but don’t touch them.
They are uncomfortable for the bird and will only become more painful if handled (especially if you pick at them).
Letting these marks heal naturally speeds up the healing process, reducing the risk of secondary bacterial infections or further transmission to other birds.
These scrabs, lesions, blisters, and accompanying pus or secretions will cause the spread or reinfection of your flock.
Vaccinate your birds to prevent another outbreak.
While there is no specific treatment, prevention is key. Vaccination is a proactive measure to control the spread of fowlpox.
Consult with a veterinarian to establish an appropriate vaccination schedule for your flock.
Is Fowl Pox the Same as Chicken Pox?
Fowl Pox is not the same as Chicken Pox.
These are different diseases that affect different species and cannot be spread from poultry to person or person to poultry.
Fowl Pox only spreads to birds and is caused by the avian poxvirus.
It is transmitted through direct contact with infected birds or contaminated surfaces.
As mentioned, the disease can manifest in two forms—dry pox and wet pox—causing lesions on unfeathered areas, mucous membranes, and respiratory tracts.
On the other hand, chickenpox is a human disease that is caused by the varicella-zoster virus.
Chickenpox is highly contagious and spreads through respiratory droplets or direct contact with the skin lesions of an infected person.
Common symptoms include itchy skin lesions, fever, and malaise.
Is Fowl Pox Contagious for People Too?
Fowl Pox does not have zoonotic risk. It cannot replicate in humans, meaning it will not spread to people.
You do not have to wear special protective equipment to the coop to take care of your sick birds, though it is a good idea always to wash your hands before and after visiting your backyard flock.
Remember that there are still some chicken and duck diseases that can make people sick.
Fowl Pox in Chickens: FAQs
Here are some of the most frequently asked questions on Fowl Pox and their answers.
How Do You Treat Fowl Pox in Chickens?
There is no specific antiviral treatment for fowl pox in chickens, which is why prevention is so important.
Infected birds should be promptly isolated from the rest of the flock to prevent the spread of the virus to healthy individuals.
Offer all birds plenty of clean, fresh water, sterilize/disinfect the coop and run, and in the future, vaccinate to prevent another outbreak.
How Do You Know If Your Chicken Has Fowl Pox?
For dry pox, look for dry, scaly lesions on unfeathered areas such as the comb, wattles, and legs.
Wet pox lesions are yellowish and can occur in the mucous membranes of the mouth, throat, and upper respiratory tract.
Chickens with lesions in the oral cavity may exhibit difficulty eating and drinking.
Respiratory distress may occur if the respiratory tract is affected.
Infected chickens may become lethargic and show a decrease in normal activity levels and feed intake.
Does Fowl Pox Go Away On Its Own?
Fowl pox is a viral disease, and in many cases, the symptoms may resolve on their own as the chicken’s immune system fights off the infection.
However, the duration of recovery can vary, and the severity of symptoms may influence the overall well-being of the affected birds.
The larger your flock, the longer Fowl Pox will stick around.
Some birds will become immune to it, while others may catch it repeatedly.
Because of this, we strongly recommend quarantining the sick birds and disinfecting the coop to prevent re-infection.
Is Fowl Pox Contagious To Humans?
Fowl pox is not known to be contagious to humans.
The avian pox virus causes fowl pox, and it primarily affects birds, especially chickens, turkeys, and other domestic poultry.
The virus is not considered a zoonotic disease, meaning it is not typically transmitted from animals to humans.
Are Eggs Safe to Eat from Chickens With Fowl Pox?
Eggs laid by chickens with fowl pox are safe to eat.
The fowl pox virus primarily affects the skin, mucous membranes, and respiratory tract of chickens, and it is not known to be transmitted through the eggs.
As mentioned, fowl pox is not zoonotic, so humans will not contract it in any way.
Is Fowl Pox Painful for Chickens?
Fowl Pox ranges from uncomfortable to painful for chickens.
These lesions are usually on the face, wattles, and legs, and it’s uncomfortable in these sensitive areas.
Wet pox lesions usually affect the mouth, throat, and respiratory tract.
These lesions may cause difficulty in breathing and swallowing, leading to greater discomfort or pain for affected chickens.
Both wet and dry fowl pox are stressful for chickens.
Will Fowl Pox Kill My Chickens?
Most of the time, Fowl Pox ‘just’ causes slow growth, reduced or stopped egg production, bad health, discomfort, and poor feed conversion.
If the Fowl Pox is wet (diphtheritic), then it could involve the oral cavity or air passage, which is much more likely to kill your chickens.
Fowl Pox in Chickens: Before You Go…
In conclusion, fowl pox poses a significant health concern for chickens, impacting their well-being and productivity.
Recognizing the distinctive lesions, monitoring behavioral changes, and promptly isolating infected birds are crucial steps in disease management.
While fowlpox may resolve independently, providing supportive care and practicing effective biosecurity measures are essential for optimal recovery and preventing further spread.
Vaccination emerges as a key preventative tool, safeguarding flocks and mitigating the impact of this viral infection.
Collaboration with a veterinarian, careful observation, and proactive measures contribute to the overall health and resilience of poultry populations against fowl pox.