What is Zoonotic Atypical Pneumonia, Know its Causes, Symptoms, Treatment, Types. Prognosis, Epidemiology

Zoonotic Atypical Pneumonia affects almost 1 in 5 people who are already suffering from pneumonia and is one of the common causes of morbidity of patients. The causative agents of Zoonotic Atypical Pneumonia don’t always respond to conventional antibiotic therapy. Therefore, fast and accurate identification of Zoonotic Atypical Pneumonia is necessary for a proper clinical treatment and a positive outcome. Moreover, pathogens of atypical pneumonia are present usually in sputum of patients in association with a rapid increase in WBC count with an absence of any alveolar outflow.

Diagnosis of Zoonotic Atypical Pneumonia

What is Zoonotic Atypical Pneumonia?

Zoonotic Atypical Pneumonia is a type of pneumonia caused by one or more zoonotic pathogens but not the traditional ones. Zoonotic Atypical Pneumonia is actually a systemic infectious ailments affecting pulmonary component and can be clinically differentiated from common pneumonia by the involvement of extra pulmonary organs. The symptoms of Zoonotic Atypical Pneumonia are totally different from typical pneumonia. Atypical pneumonia is always practically mono-microbial. Three main zoonotic pathogens cause Zoonotic Atypical Pneumonia, which includes Chlamydophila psittaci causing Psittacosis; Francisella tularensis causing Tularemia; and Coxiella burnetii causing Q fever.

Symptoms of Zoonotic Atypical Pneumonia

Some common symptoms of Zoonotic Atypical Pneumonia are as follows:

  • Resistant to common antibiotic medications such as beta lactams including penicillin or sulfonamide
  • Shivering and cough
  • Common symptoms of Zoonotic Atypical Pneumonia include upper respiratory tract infection along with mild or high fever
  • Muscle pain with stiff joints is also another symptoms of Zoonotic Atypical Pneumonia
  • Absence of alveolar discharges
  • Extra pulmonary symptoms with secretion of moderate amount of sputum
  • Breathing trouble can also be a symptom of Zoonotic Atypical Pneumonia
  • Chest pain that worsens in vigorous coughing
  • Excessive sweating with moist sticky skin
  • Leukocytosis is not seen
  • Loss of energy and appetite, which may lead to fatigue
  • Infection doesn’t spread to the entire lobar area but remain resisted to one place inside the pulmonary lobes.

Types of Zoonotic Atypical Pneumonia

Zoonotic Atypical Pneumonia is basically caused by three zoonotic pathogens: Chlamydophila psittaci, Francisella tularensis, and Coxiella burnetii and therefore are of three types:

  • Psittacosis: Also known as parrot fever, is a zoonotic lethal infectious disease caused by bacterial species Chlamydophila psittaci, and spreads through different species of bird like parrot, macaw, hen, duck, pigeon, etc. After 5-15 days of infection in human it shows systemic illness along with severe atypical pneumonia. Other symptoms include: joint ache, high fever, nose bleeding, conjunctivitis, etc. In severe cases, it may cause massive pneumonitis symptoms together with hepatomegaly, endocarditis, neurological dysfunction, keratoconjunctivitis and ultimately leads to death.
  • Tularemia: Tularemia or commonly referred to as rabbit fever is usually caused by Gram (−)ve bacterial pathogen called Francisella tularensis. It is very fussy and unrestricted intercellular pathogenic bacterium, which needs cysteine for development and is highly infectious and spread through aerosol or by animal vectors like ticks or mosquito. Infection takes 3-5 days to incubate and shows clinical signs like loss of appetite, fever (mild to high), sepsis symptoms, lethargy and other pneumonia symptoms that leads to death.
  • Q-fever: Q-fever is an infectious disease caused by obligate small intracellular bacterial pathogenic species named as Coxiella burnetii. The pathogen is found in domestic mammals like cattles, dogs or cats and thus spread through inhalation or contamination with urine, milk or other body fluids. Most common symptoms include: upper respiratory symptoms, pleuritic ache, nausea, mental confusion, severe headache, cough and cold, joint stiffness, excessive perspiration and in severe stages it may lead to life-threatening atypical pneumonia or acute respiratory distress syndrome.

Epidemiology of Zoonotic Atypical Pneumonia

Zoonotic Atypical Pneumonia is difficult to diagnosis and is also non-responsive towards common antibiotic therapies. Even the clinical manifestation of the disease cannot be differentiated easily from the other pathogen-causing pneumonia. Therefore, more clinical investigation is required which is very much time consuming and show low sensitivity and thus leads to further clinical complication and outlook.

Infection may spread throughout the year and can cause epidemic in smaller communities of the society. The disease transmits through contact between person to person or in closed populated areas like schools and colleges, intensive care units and wards of hospitals, children care centers, public places and transports, etc. As the diagnosis is time consuming as well as difficult therefore mortality rates increases fast and prevention of infection becomes the priority.

Prognosis of Zoonotic Atypical Pneumonia

Most of the patients having Zoonotic Atypical Pneumonic symptoms survive in better condition with proper antibiotic treatment but some pathogen-causing pneumonia can be lethal in severe condition. Problems become more difficult to handle if patients have medical history of kidney failure, Chronic Obstructive Pulmonary Diseases, weak immune system or Diabetes Mellitus; in such cases mortality rate is very high.

Risk Factors of Zoonotic Atypical Pneumonia

Not every person who is exposed to those pathogenic bacteria will catch the infection as soon as they are exposed to them. Risk factors that increase the chance to get affected by this pathogenic bacterial infection of Zoonotic Atypical Pneumonia include the following:

  • Adult or older age
  • Poor immune system
  • Smoking or drinking habits
  • Any type of chronic ailment.

Causes of Zoonotic Atypical Pneumonia

Zoonotic Atypical Pneumonia is a systemic disease that occurs mostly due to bacterial pathogenic infection. The common causative agents of Zoonotic Atypical Pneumonia include three bacterial pathogens, namely,

  • Chlamydophila psittaci: Responsible for causing psittacosis, which in severe condition leads to atypical pneumonia.
  • Francisella tularensis: Causing tularemia and shows atypical pneumonia symptoms.
  • Coxiella burnetii: Mainly leads to Q fever that in severe cases results in pneumonia or acute respiratory distress syndrome.

Some cases of Zoonotic Atypical Pneumonia occur due to viral, fungal or protozoan infection. Zoonotic Atypical Pneumonia mainly affects people with age around 40 years and condition of pneumonic symptoms varies from mild to severe. Around 5-15% of pneumonias that occur worldwide each year is atypical and is usually mild.

Diagnosis of Zoonotic Atypical Pneumonia

People diagnosed with early pneumonia symptoms have to undergo some physical examination. Depending on the results of chest X-ray or radiographs, your doctor can be sure that whether you are suffering from acute atypical pneumonic symptoms or other respiratory diseases like bronchitis. As the severity of the disease increases other tests can be done to be sure that a person is infected with Zoonotic Atypical Pneumonia and the tests are:

  • Total blood culture
  • Arterial blood examination
  • Blood test for specific bacterial infection
  • Blood tests for identification of particular antibodies
  • CBC or complete blood count
  • Bronchoscopy
  • Throat swab culture
  • Gram staining study of sputum
  • Mucus culturing from lungs
  • Chest CT scan
  • Open lungs biopsy test
  • Complete urine culture

In Zoonotic Atypical Pneumonia cases, infiltration usually spreads in a fan-shaped manner from the bronchus region to the entire periphery of the surface of lungs. In this spreading process lower lobe of lungs may involve but sometimes the infection may affect both or any one of the two lobes.

Treatment of Zoonotic Atypical Pneumonia

Generally two-steps of treatment are involved in treating Zoonotic Atypical Pneumonia symptoms. Further details are discussed below:

  • Antimicrobial Therapy or Antibiotic Treatment to Treat Zoonotic Atypical Pneumonia: As the patients suffering from Zoonotic Atypical Pneumonia is resistant towards beta-lactam or sulfonamide, therefore following antibiotic medications are used to treat the disease complications which includes:
    • Azithromycin
    • Telithromycin
    • Clarithromycin
    • Doxycycline or Tetracycline
    • Erythromycin
    • Rifampin and Macrolides
    • Fluoroquinolones including levofloxacin.
  • Antibiotics for Zoonotic Atypical Pneumonia are given orally directly at home.
  • However, in severe conditions of Zoonotic Atypical Pneumonia, antibiotics are injected intravenously along with adequate oxygen supply.
  • Antibiotic treatment for Zoonotic Atypical Pneumonia should be continued for more than 2 weeks as per doctor’s advice.

Self-help Tips for Dealing with Zoonotic Atypical Pneumonias

Other than medication, some steps of treatment should also be followed properly at home in order to get rid of Zoonotic Atypical Pneumonia symptoms. This includes self-care treatment measures mainly followed at home to get fast relief.

  • Take enough of rest and sleep. Leave the household work to others for few weeks.
  • Drink plenty of water and other fluid like soups or juices so as to decrease secretion and also for recovery of phlegm.
  • Manage high fever either with aspirin or NSAIDs including Ibuprofen or Naproxen. You may also take acetaminophen to lower down your temperature. However, never give aspirin to small children.
  • Without doctor’s advice don’t take any cough medicines. As cough medicines usually makes harder to bring up cough properly with excess sputum.


Most people with Zoonotic Atypical Pneumonia usually recover faster with proper antibiotic treatment, but it is advised to follow the doctor’s prescription thoroughly without missing anything. There are chances to get back the infection if the complete course of antibiotic therapy is not followed. Mostly the symptoms for Zoonotic Atypical Pneumonia are mild and can be treated quickly but complication may arise if left unnoticed. As per some published data it is seen that the risk for getting Zoonotic Atypical Pneumonia infection is increasing day by day. So prevention can be taken by stopping smoking and following proper hygiene like washing hands before eating, cover up your mouth while cough and sneezing, etc.

Also Read:

Team PainAssist
Team PainAssist
Written, Edited or Reviewed By: Team PainAssist, Pain Assist Inc. This article does not provide medical advice. See disclaimer
Last Modified On:April 3, 2018

Recent Posts

Related Posts