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Streptococcus Infection (Bacterial Infection with Streptococci) in Dogs

Occurrence: common
Location of illness: General/Whole body

Author: Dr. med. vet. Gisa Löwe | Last modified: 06.11.2025

A Streptococcus infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. in dogs is a bacterial infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. caused by bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. of the genus Streptococcus. These infections can cause a variety of symptoms, depending on the affected area of the body, ranging from mild to severe conditions.

The most important facts at a glance

Streptococci are gram-positive bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. that can cause infections in dogs, especially through Streptococcus canis and Streptococcus equi subsp. zooepidemicus. These bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. are often found in the normal microflora of dogs but can cause disease in the event of a weakened immune systemThe immune system is the body's defense system against infectious agents such as bacteria, viruses, fungi, and parasites. It comprises a complex network of organs, cells, and molecules that work together to protect the body. or skin injuries. Transmission usually occurs through direct contact with infected animals or contaminatedContaminated describes something that has been polluted by harmful microorganisms, chemicals, or other dangerous substances. In veterinary medicine, this can affect food, water, toys, or the environment. surfaces. Symptoms include pain, fever, lethargy, joint inflammation, cough, and loss of appetite. DiagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. is made through clinical examinations and laboratory analyses to identify the pathogenA pathogen is a microorganism or virus that can cause disease in its host. Pathogens include bacteria, viruses, fungi, and parasites.. Treatment is with antibiotics, based on sensitivity tests, supported by symptom-relieving measures such as pain relievers and fluid therapyTherapy refers to the treatment of diseases or disorders with the aim of alleviating symptoms, promoting healing, or improving quality of life. Therapies can be medicinal, surgical, or through other medical interventions.. A complete course of antibiotics is important to avoid resistanceResistance refers to the ability of microorganisms to withstand the effects of antibiotics, antifungals, or other antimicrobial drugs. Resistance can also refer to the body's ability to be insensitive to diseases or toxins. formation. The prognosisThe prognosis is the prediction of the likely course and outcome of a disease based on the general state of health, the nature of the disease, and the response to treatment. It can provide information on how a disease is expected to develop. is usually good with timely treatment but may be more guarded in severe infections. Preventive measures include good hygiene, avoiding contact with infected animals, and regular veterinary examinations. Research focuses on the genetic analysis of the bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease., development of vaccines, and alternative therapies to combat antibiotic resistanceResistance refers to the ability of microorganisms to withstand the effects of antibiotics, antifungals, or other antimicrobial drugs. Resistance can also refer to the body's ability to be insensitive to diseases or toxins.. A multidisciplinary approach is essential to promote the health of dogs.

Causes

Streptococci are a group of gram-positive bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. that occur in chain form and can cause infections in both animals and humans. There are many different types of streptococci, each of which can cause different diseases. The most common streptococcal species affecting dogs include Streptococcus canis and Streptococcus equi subsp. zooepidemicus.

Streptococcus canis is an opportunistic bacterium that is often found in the normal microflora of the skin, throat, and intestines of dogs. However, under certain conditions, such as a weakened immune systemThe immune system is the body's defense system against infectious agents such as bacteria, viruses, fungi, and parasites. It comprises a complex network of organs, cells, and molecules that work together to protect the body. or injury to the skin, this bacterium can cause disease. Streptococcus equi subsp. zooepidemicus is better known for infections in horses but can also infect dogs.

Streptococcus is usually transmitted through direct contact with infected animals or contaminatedContaminated describes something that has been polluted by harmful microorganisms, chemicals, or other dangerous substances. In veterinary medicine, this can affect food, water, toys, or the environment. surfaces. In some cases, airborne transmission can also occur, especially in densely populated animal shelters or kennels. The bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. can enter through open wounds or infect the respiratory tractThe respiratory tract includes the organs and structures involved in the breathing process, including the nose, pharynx, larynx, trachea, bronchi, and lungs. through inhalationInhalation is the act of breathing air or other substances into the lungs through the nose or mouth. In dogs and cats, inhalation of toxins, smoke, or allergens can lead to respiratory problems..

Symptoms

Very common symptoms:

Common symptoms:

Rare symptoms:

Septic Shock

The symptoms of a Streptococcus infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. in dogs can vary depending on the affected area of the body. Common symptoms include fever, loss of appetite, and general weakness. With skin infections, redness, swelling, and pus formation can occur.

In respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. infections, dogs often show a cough, nasalNasal refers to the nose and nasal cavities. In veterinary medicine, this can involve examinations, treatments, or diseases affecting the nose of dogs and cats. discharge, and respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress. Infections in the mouth or throat can lead to increased salivation, difficulty swallowing, and painful chewing. In severe cases, especially if the bacterium enters the bloodstream, systemic symptoms such as sepsis can occur, which can be life-threatening.

Diagnosis

DiagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. of a Streptococcus infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. is made through a combination of clinical examination and laboratory tests. The veterinarian will first perform a thorough physical examination of the dog and assess the symptoms as well as the animal’s medical historyThe medical history is the systematic collection of a patient's medical history through questioning. It includes information about previous illnesses, treatments, allergies, and lifestyle habits..

To identify the specific cause of the infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease., samples can be taken from affected areas. These samples, such as swabs from skin lesions or nasalNasal refers to the nose and nasal cavities. In veterinary medicine, this can involve examinations, treatments, or diseases affecting the nose of dogs and cats. discharge, are then cultured in a laboratory to confirm the presence of streptococci. Sensitivity tests can also be performed to determine the most effective antibiotics for treatment.

Therapy

Treatment of a Streptococcus infection in dogs is usually with antibiotics. The choice of antibiotic is based on the results of sensitivity tests to ensure that the chosen drug is effective against the specific type of bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease.. Commonly prescribed antibiotics include penicillinsPenicillins are a class of antibiotics derived from the Penicillium mold. They are used to treat bacterial infections by disrupting the cell wall synthesis of the bacteria. and cephalosporins.

In addition to antibiotic therapyTherapy refers to the treatment of diseases or disorders with the aim of alleviating symptoms, promoting healing, or improving quality of life. Therapies can be medicinal, surgical, or through other medical interventions., supportiveSupportive refers to supportive treatments that aim to alleviate symptoms and improve quality of life without directly treating the underlying cause of the disease. treatment may be necessary to relieve symptoms and promote recovery. This includes pain relievers, antipyreticAntipyretic drugs are medications used to reduce Fever. They work by acting on the heat-regulating center in the brain, thus regulating body temperature. These medications can be used in dogs and cats to reduce Fever, which is often a symptom of an infection or inflammation. medications, and in some cases intravenous fluids to stabilize fluid balance.

It is important to complete the entire course of antibiotics as prescribed by the veterinarian, even if symptoms improve, to ensure that all bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. are killed and no resistanceResistance refers to the ability of microorganisms to withstand the effects of antibiotics, antifungals, or other antimicrobial drugs. Resistance can also refer to the body's ability to be insensitive to diseases or toxins. develops.

Prognosis and follow-up care

The prognosisThe prognosis is the prediction of the likely course and outcome of a disease based on the general state of health, the nature of the disease, and the response to treatment. It can provide information on how a disease is expected to develop. for dogs with a Streptococcus infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. depends on various factors, including the severity of the infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease., the affected area of the body, and the dog’s general health. With timely diagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. and appropriate treatment, the prognosisThe prognosis is the prediction of the likely course and outcome of a disease based on the general state of health, the nature of the disease, and the response to treatment. It can provide information on how a disease is expected to develop. is usually good, and most dogs recover completely.

However, in severe cases, especially with systemic infections such as sepsis, the prognosisThe prognosis is the prediction of the likely course and outcome of a disease based on the general state of health, the nature of the disease, and the response to treatment. It can provide information on how a disease is expected to develop. may be more guarded and requires more intensive medical intervention and care. Early intervention is crucial to avoid complications and increase the chances of survival.

Prevention

To minimize the risk of a Streptococcus infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. in dogs, dog owners should pay attention to good hygiene and ensure that their pet lives in a clean environment. Regular bathing and brushing can help promote skin health and reduce the risk of skin infections.

It is also important to avoid contact with infected animals and to ensure that dog contact areas, such as kennels or pet boarding facilities, are cleaned and disinfected regularly. Vaccinations can also play a role, especially in environments with high infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. pressure.

Finally, it is beneficial to strengthen the dog’s immune systemThe immune system is the body's defense system against infectious agents such as bacteria, viruses, fungi, and parasites. It comprises a complex network of organs, cells, and molecules that work together to protect the body. through a balanced diet and regular veterinary examinations to promote general health and reduce susceptibility to infections.

Outlook on current research

Research surrounding Streptococcus infections in dogs has made significant progress in recent years. Streptococci are a group of bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. that can cause various infections, and they are known for their ability to multiply and spread rapidly. Scientists are focusing on understanding the pathogenesisPathogenesis describes the process of the origin and development of a disease, including the mechanisms that lead to the disease's symptoms and signs. of these bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. to develop better treatment methods.

A significant part of current research deals with the genetic analysis of streptococcal strains. By deciphering the genomes of these bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease., researchers are trying to identify specific genes that are responsible for their virulence and antibiotic resistanceResistance refers to the ability of microorganisms to withstand the effects of antibiotics, antifungals, or other antimicrobial drugs. Resistance can also refer to the body's ability to be insensitive to diseases or toxins.. These genetic insights could help develop targeted therapies that improve the effectiveness of treatment by exploiting specific weaknesses of the bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease..

Another focus of research is on the development of vaccines against Streptococcus infections in dogs. Although there are already vaccines for humans against some streptococcal types, these are not directly transferable to dogs. Researchers are working to develop vaccines that are specifically effective for the strains commonly found in veterinary medicine. These vaccines could represent a breakthrough in the preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. of Streptococcus infections.

In addition, intensive research is being conducted into alternative treatment methods to counteract increasing antibiotic resistanceResistance refers to the ability of microorganisms to withstand the effects of antibiotics, antifungals, or other antimicrobial drugs. Resistance can also refer to the body's ability to be insensitive to diseases or toxins.. These include the development of bacteriophage therapies, which kill bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. through virus-like organisms, as well as the use of probiotic approaches to influence the microbiome of dogs in such a way that it becomes more resistantResistant means being insensitive to a substance, drug, or treatment. In dogs and cats, resistance can refer to the ineffectiveness of antibiotics against certain bacterial strains or the insensitivity of parasites to certain pesticides. to streptococci.

The role of the environment and living conditions of dogs is also being investigated to find out which factors increase the risk of a Streptococcus infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease.. Studies show that dogs in close communities or under poor hygienic conditions have a higher risk of infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease.. These findings could help to develop preventive measures that significantly reduce the risk of infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. through better hygiene standards and living conditions.

In summary, current research shows that a multidisciplinary approach is necessary to effectively manage the challenges posed by Streptococcus infections in dogs. By combining genetic research, vaccineA vaccine is a substance that stimulates the immune system to develop immunity against specific pathogens without causing the disease itself. Vaccines may contain weakened or inactivated pathogens, toxoids, or recombinant antigens. development, alternative therapies, and preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. strategies, it will be possible to significantly improve the health of dogs worldwide.

Frequently asked questions (FAQs)

What are streptococci? Streptococci are a group of spherical bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. that occur in chain form and can cause a variety of infections in animals and humans. In dogs, they can cause skin infections, respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. infections, and other diseases.
How do dogs get infected with streptococci? Dogs can become infected through direct contact with an infected animal or through contaminatedContaminated describes something that has been polluted by harmful microorganisms, chemicals, or other dangerous substances. In veterinary medicine, this can affect food, water, toys, or the environment. objects and surfaces. Droplet infections via the air are also possible, especially in confined spaces or animal shelters.
What symptoms do dogs show with a streptococcal infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease.? The symptoms of a streptococcal infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. in dogs can vary but often include fever, cough, nasal discharge, swollen lymph nodes, and skin irritation. Severe cases can lead to pneumonia or sepsisSepsis is a life-threatening condition caused by the body's overwhelming response to an infection, which can lead to damage to its own tissues and organ failure..
How is a streptococcal infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. diagnosed? DiagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. is usually made through a combination of clinical examination, blood tests, and detection of the bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease. in swabs from affected areas. A veterinarian can create a bacterial culture to identify the exact pathogenA pathogen is a microorganism or virus that can cause disease in its host. Pathogens include bacteria, viruses, fungi, and parasites..
How is a streptococcal infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. treated? Treatment usually includes antibiotics to kill the bacteriaBacteria are microscopic, single-celled organisms that exist in almost every environment on Earth. Some types of bacteria are beneficial or even essential to life, while others can cause disease.. The choice of antibiotic depends on the sensitivity of the specific pathogenA pathogen is a microorganism or virus that can cause disease in its host. Pathogens include bacteria, viruses, fungi, and parasites.. Anti-inflammatory drugsAnti-inflammatory drugs are medications that reduce inflammation. They can be divided into nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids and are used in dogs and cats to reduce Inflammatory conditions and Pain. and fluid therapies can be given to relieve symptoms.
Can a streptococcal infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease. be prevented in dogs? Good hygiene, regular veterinary examinations, and vaccinations can help reduce the risk of infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease.. It is also important to avoid contact with infected animals and to keep living conditions clean and stress-free.
Are streptococcal infections in dogs contagiousContagious means infectious. Diseases that can easily be transmitted from one animal to another or from animals to humans are referred to as contagious. to humans? Some streptococcal strains can be zoonotic, meaning they can be transmitted from animals to humans. It is important to observe good hygiene measures when caring for an infected dog to minimize the risk of transmission.
Are there risk factors that increase the likelihood of infectionAn infection is the colonization and multiplication of pathogens such as bacteria, viruses, fungi, or parasites in an organism, which often, but not always, leads to a disease.? Yes, dogs with weakened immune systems, older dogs, and puppies are more susceptible to infections. Dogs living in crowded or unhygienic environments also have a higher risk of becoming infected.
Can streptococcal infections in dogs become chronicChronic refers to a condition or disease that is long-lasting or permanent. Chronic diseases often develop slowly and can lead to persistent or recurring health problems over time.? Typically, streptococcal infections are acuteAcute refers to a condition that occurs suddenly and is usually of short duration. In a medical context, it describes symptoms or illnesses that can quickly become serious and require immediate attention., but if left untreated or inadequately treated, they can become chronicChronic refers to a condition or disease that is long-lasting or permanent. Chronic diseases often develop slowly and can lead to persistent or recurring health problems over time. and lead to recurring health problems.
Why is research on streptococcal infections in dogs important? Streptococcal infections can cause serious health problems in dogs and are potentially transmissible to humans. Research helps to develop new treatment methods and preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. strategies to protect the health of pets and their owners.