Cat G-Strep

"GStrep" is the short version of "Group G Streptococcal". "GStrep" is part of the normal microbial flora of the gastrointestinal tract, vagina, and skin of cats. "Streptococci" are normally non-pathogenic, but a few species can cause significant morbidity and mortality ranging from death in young kittens, from pyometra, pneumonia and upper respiratory infection.

Beta-haemolytic streptococci belong to the Lancefield groups A, B, C or G classification.

  • Genus: Streptococcus
    • Group A Streptococcal
      • S. Pneumoniae
      • S. Zooepidemicus
    • Group B Streptococcal
      • S. Agalactiae
    • Group C Streptococcal
      • S. Equi
    • Group G Streptococcal
      • S. Canis


Requires specialized equipment to grow streptococci and veterinary lavatories are reluctant to incubate something for 10 days (High Cost).  Many veterinarians are not aware of G-Strep and can mistake it as Upper Respiratory Infection, Chlamydia,Calicivirus or Panleukopenia. General you should know if you are dealing with a Upper Respiratory Infection because it affects multiple cats within a household with symptoms of running nose, gunky eyes, sneezing fits and so on.

It is suggested to preform a feline upper respiratory PCR test and bacterial culture to rule out other possible ailments that present with the SAME symptoms such as Feline Mycoplasma. 

Treatment for G-strep is for a gram-positive bacterium. It will not treat problems such as Mycoplasma.


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"Streptococci Infections" in adult cats have a high probability of show no symptoms! Unfortunately kittens have a weak immune system making them more subseptable to death may show symptoms prior to death. Many kittens will show no clinical symptoms of illness until hours before death. Usually not all of the kittens in the litter are affected. Kittens are typically infected with the bacteria from the queen's vagina during birth. This can result in an abscess of the umbilicus which spreads into the liver and abdominal cavity, leading to peritonitis and septicaemia. Some kittens may have an obvious umbilical abscess or swelling.

  • Unexplained spontaneous abortions or absorption.
  • Unexplained death of newborn kittens.
  • Birth abnormalities (Intestines on outside, cleft palette).
  • Affected kittens die between 1 and 10 days, rare cases of up to 6 weeks old.
  • No clinical symptoms of illness until hours before death.
  • Affected kittens show slower than average weight gain.
  • All the signs of Chlamydia but negative on testing.
  • Difficulty swallowing due to swelling.
  • Fever
  • Lethargy
  • Coughing
  • Pneumonia


Consult with your veterinarian before any treatment.


  • Non-Pregnant: Clindamycin (Antirobe), also referred to as Clin-Tabs, 25mg per 6-10 lbs, twice a day for 20 days. Must run all breeding adults and potential breeders. All cats in the household, including spays/neuters, males and older kittens should be treated. Tip for getting cat's to take the capsules, open capsule and mix powder with chicken baby food.
  • Pregnant: Same as above plus the following. Clavomox (amoxicillin/clavulanate) and/or azithromycin for 5-10 days before giving birth. Give the mother long lasting penicillin 1cc subQ immediately following the birth.
  • Newborn: As soon as the kittens are born, dip the cords in iodine then administer "long lasting penicillin Injection" (benzathine/procaine pen G), acts on susceptible bacteria within 15 minutes and keeps working for 48 hours. Draw up 1.5 cc sterile water or saline into a 3cc syringe. Then draw up .25cc/ml long lasting penicillin. Shake the syringe. Take off the needle. Insert the needle of a 1cc (tuberculin) syringe into the 3cc syringe (where you took off the needle) and draw off .25cc/ml of this mixture into separate syringes for each kitten. Prepare this solution no more than a couple of hours before the kittens are born (refrigerate). Give each kitten this injection subQ.


  • Dehydration: Re-hydration is also important for restoring the body with fluid and flushing the system of the infection. Kittens will be unable to digest food if too dehydrated.
  • Weight-loss: All felines, especially kittens, in your household should be weighed immediately so you can determine weightloss.
  • Respiratory Distress: Cat(s) showing signs of respiratory distress of any level should be seen by the veterinarian immediately they may require intensive veterinary supportive care (Incubator with oxygen therapy, fluids and antibiotics).



  • After clindamycin treatment, the G Strep will most likely still be retained in the normal flora at a very low level.  Therefore, the cat could always be a potential G Strep carrier with respect to breeding only.  In other words, we should be concerned with the breeding aspects of the Strep G rather than whether the cats do not have any G Strep at all, since the clindamycin will most likely not get every last bit of it - even at a 3 week dose. The other thing (which you may already know) is that a culture will take about 10 days, and will most likely come back with "normal flora", because the G Strep is at such a low level that it won't "register" on the lab tests.
  • Beta-haemolytic Streptococci are usually resistant to sulfamethoxazole, tetracycline and gentamicin. Resistance to penicillins or cephalosporins is very rarely detected.

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