Prevalence and Incidence of Psittacosis

Prevalence/Incidence of Psittacosis: Online Medical Books

16 MEDICAL BOOKS ONLINE! Review excerpts from medical books online, free, without registration, for more information about the prevalence and/or incidence of Psittacosis.

Pneumonia: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

Pneumonia can be classified in several ways:

❑ Microbiologic etiology — Pneumonia can be viral, bacterial, fungal, protozoan, mycobacterial, mycoplasmal, or rickettsial in origin. (See Types of pneumonia, pages 538 to 541.)

❑ Location — Bronchopneumonia involves distal airways and alveoli; lobular pneumonia, part of a lobe; and lobar pneumonia, an entire lobe.

❑ Type — Primary pneumonia results from inhalation or aspiration of a pathogen; it includes pneumococcal and viral pneumonia. Secondary pneumonia may follow initial lung damage from a noxious chemical or other insult (superinfection), or may result from hematogenous spread of bacteria from a distant focus.

Predisposing factors for bacterial and viral pneumonia include chronic illness and debilitation, cancer (particularly lung cancer), abdominal and thoracic surgery, atelectasis, common colds or other viral respiratory infections, such as acquired immunodeficiency syndrome, chronic respiratory disease (chronic obstructive pulmonary disease [COPD], asthma, bronchiectasis, and cystic fibrosis), influenza, smoking, malnutrition, alcoholism, sickle cell disease, tracheostomy, exposure to noxious gases, aspiration, and immunosuppressive therapy.

Predisposing factors for aspiration pneumonia include old age, debilitation, artificial airway use, nasogastric (NG) tube feedings, impaired gag reflex, poor oral hygiene, and decreased level of consciousness.

In elderly patients and patients who are debilitated, bacterial pneumonia may follow influenza or a common cold. Respiratory viruses are the most common cause of pneumonia in children ages 2 to 3. In school-age children, mycoplasma pneumonia is more common.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Ornithosis: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

Psittacine birds (parrots, parakeets, and cockatoos), pigeons, and turkeys may harbor C. psittaci in their blood, feathers, tissues, nasal secretions, liver, spleen, and feces. Transmission to humans occurs primarily through inhalation of dust containing C. psittaci from bird droppings; less commonly, through direct contact with infected secretions or body tissues, as in laboratory personnel who work with birds. Person-to-person transmission seldom occurs but usually causes severe ornithosis.

Incidence is higher in women and in people ages 20 to 50.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Idiopathic bronchiolitis obliterans with organizing pneumonia: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

BOOP has no known cause. However, other forms of bronchiolitis obliterans and organizing pneumonia may be associated with specific diseases or situations, such as bone marrow, heart, or heart-lung transplantation; collagen vascular diseases, such as rheumatoid arthritis and systemic lupus erythematosus; inflammatory diseases, such as Crohn’s disease, ulcerative colitis, and polyarteritis nodosa; bacterial, viral, or mycoplasmal respiratory infections; inhalation of toxic gases; and drug therapy with amiodarone, bleomycin, penicillamine, or lomustine.

Much debate still exists about the various pathologies and classifications of bronchiolitis obliterans. Most patients with BOOP are between ages 50 and 60. Incidence is equally divided between men and women. A smoking history doesn’t seem to increase the risk of developing BOOP.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Colorado tick fever: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

Colorado tick fever is transmitted to humans by a hard-shelled wood tick called Dermacentor andersoni. The adult tick acquires the virus when it bites infected rodents and remains permanently infective.

Incidence is high in Colorado, where up to 15% of people who regularly camp show past exposure. It's much less common in the rest of the United States.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Lassa fever: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

A chronic infection in rodents, Lassa virus is transmitted to humans by contact with infected rodent urine, feces, and saliva. The virus enters the bloodstream, lymph vessels, and respiratory and digestive tracts. It then multiplies in the cells of the reticuloendothelial system. In the early stages of this illness, when the virus is in the throat, human transmission may occur through inhalation of infected droplets.

As many as 100 cases of Lassa fever occur annually in western Africa; the disease is rare in the United States.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Pneumocystis carinii pneumonia: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

P. carinii, the cause of PCP, usually is classified as a protozoan, although some investigators consider it more closely related to fungi. The organism exists as a saprophyte in the lungs of humans and various animals as part of the normal flora in most healthy people. It becomes an aggressive pathogen in the immunocompromised patient. Impaired cell-mediated (T-cell) immunity is thought to be more important than impaired humoral (B-cell) immunity in predisposing the patient to PCP, but the immune defects involved are poorly understood. P. carinii becomes activated in immunocompromised patients when the CD4⁺ T-cell count falls below 200/µl.

P. carinii invades the lungs bilaterally and multiplies extracellularly. As the infestation grows, alveoli fill with organisms and exudate, impairing gas exchange. The alveoli hypertrophy and thicken progressively, eventually leading to extensive consolidation.

The primary transmission route seems to be air, although the organism is already present in most people. The incubation period probably lasts for 4 to 8 weeks.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Relapsing fever: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

The body louse (Pediculus humanus corporis) carries louse-borne relapsing fever (B. recurrentis), which typically occurs in epidemics during wars, famines, and mass migrations. Cold weather and crowded living conditions also favor the spread of body lice.

Inoculation takes place when the victim crushes the louse, causing its infected blood or body fluid to soak into the victim's bitten or abraded skin or mucous membranes.

Louse-borne relapsing fever is most common in North and Central Africa, Europe, Asia, and South America. No cases of louse-borne relapsing fever have been reported in the United States since 1900.

Tick-borne relapsing fever, however, is found in the United States and is caused by at least 15 Borrelia species; the three species most commonly identified with tick carriers are B. hermsii (associated with Ornithodoros hermsi), B. turicatae (associated with O. turicata), and B. parkeri (associated with O. parkeri). This form of the disease is most prevalent in Texas and other western states, usually during the summer when ticks and their hosts (chipmunks, goats, squirrels, rabbits, mice, rats, owls, lizards, and prairie dogs) are most active. In the colder weather, outbreaks sometimes afflict people such as campers who sleep in tick-infested cabins.

Because tick bites are virtually painless and most Ornithodoros ticks feed at night but don’t imbed themselves in the victim’s skin, many people are bitten unknowingly.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Rheumatic fever and rheumatic heart disease: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

Rheumatic fever appears to be a hypersensitivity reaction to a group A beta-hemolytic streptococcal infection, in which antibodies manufactured to combat streptococci react and produce characteristic lesions at specific tissue sites, especially in the heart and joints. Because very few persons (3%) with streptococcal infections ever contract rheumatic fever, altered host resistance must be involved in its development or recurrence. Although rheumatic fever tends to be familial, this may merely reflect contributing environmental factors. For example, in lower socioeconomic groups, incidence is highest in children between ages 5 and 15, probably as a result of malnutrition and crowded living conditions. This disease strikes generally during cool, damp weather in the winter and early spring. In the United States, it’s most common in the northern states.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Rocky Mountain spotted fever: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

R. rickettsii is transmitted to a human or small animal by the prolonged bite (4 to 6 hours) of an adult tick — the wood tick (Dermacentor andersoni) in the west and by the dog tick (Dermacentor variabilis) in the east. Occasionally, it's acquired through inhalation (it can occur in laboratory settings where aerosolization of blood and specimens may occur) or through the contact of abraded skin with tick excreta or tissue juices. (This explains why people should'nt crush ticks between their fingers when removing them from other people and animals.) In most tick-infested areas, 1% to 5% of the ticks harbor R. rickettsii.

Endemic throughout the continental United States, RMSF is particularly prevalent in the southeast and southwest. Because RMSF is associated with outdoor activities, such as camping and backpacking, the incidence of this illness is usually higher in the spring and summer. Epidemiologic surveillance reports for RMSF indicate that the incidence is also higher in children ages 5 to 9, men and boys, and whites.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Chlamydial infections: Causes and incidence
(Professional Guide to Diseases (Eighth Edition))

Transmission of C. trachomatis primarily follows vaginal or rectal intercourse or orogenital contact with an infected person. Because symptoms of chlamydial infections commonly appear late in the disease’s course, sexual transmission of the organism typically occurs unknowingly. Children born of mothers who have chlamydial infections may contract associated conjunctivitis, otitis media, and pneumonia during passage through the birth canal.

Chlamydial infections are the most common sexually transmitted diseases in the United States, affecting an estimated four million people in the United States each year.

» READ BOOK EXCERPT ONLINE »

Source: Professional Guide to Diseases (Eighth Edition), 2005

Chlamydial Infections: Chlamydial Infections - epidemiology
(The 5-Minute Pediatric Consult)

• C. trachomatis:
  • There are at least 15 serologically distinct variants (serovars).
  • C. trachomatis is the most frequent cause of epididymitis in sexually active young men.
  • Incubation period: 5–14 days after delivery for conjunctivitis
  • The possibility of sexual abuse should be considered in older infants and children with vaginal, urethral, or rectal C. trachomatis.
• C. psittaci (psittacosis/ornithosis):
  • Both healthy and sick birds can transmit the bacteria via the airborne route by their excrement or secretions.
  • Important sources of human disease are parakeets, parrots, macaws, pigeons, and turkeys.
  • Workers in poultry slaughter plants, poultry farms, pet shops, laboratory workers, and pet owners are at high risk.
  • Although usually rare in children, it should be considered in any child with environmental exposure who develops an atypical pneumonia. The incubation period is 7–14 days.
• C. pneumoniae: Antigenically, morphologically, and genetically distinct from other chlamydiae
  • It is assumed to be transmitted from person to person through aerosolized respiratory secretions.
  • C. pneumoniae has recently been associated with atherosclerotic cardiovascular disease. Limited evidence associates C. pneumoniae with asthma and bronchospasm, Alzheimer disease, multiple sclerosis, Kawasaki disease, HIV and other immune disorders, malignancy, otitis media, and episodes of acute chest syndrome in patients with sickle cell disease.
  • Coinfection with other respiratory pathogens, especially M. pneumoniae and Streptococcus pneumoniae, is frequent.
  • Incubation period: ~21 days

Chlamydial Infections - incidence

C. trachomatis:

• This is the most common reportable sexually transmitted infection in the US. The number of new infections exceeds 4 million annually.
• Rates of infection in adolescent girls are 15–20%.
• 23–55% of all cases of nongonococcal urethritis in men are caused by C. trachomatis. Up to 50% of men with gonorrhea may be coinfected with C. trachomatis.
• C. trachomatis pneumonia usually develops in infected infants <2 months of age (2 weeks to 5 months). The contagiousness of pulmonary disease is unknown, but is considered low.
• Half of the neonates born to infected mothers via vaginal delivery will acquire C. trachomatis. Conjunctivitis may develop in 30–50%. Pneumonia may develop in up to 30% of infants with nasopharyngeal infection.
• Ocular trachoma caused by serovars A, B, Ba, and C is the most common cause of preventable blindness in the world, but is rare in the US.

Chlamydial Infections - prevalence

C. pneumoniae:

• Increased prevalence rates of C. pneumoniae specific antibody have been documented in school-age children, reaching 30–45% in adolescents.
• Studies of CAPs in children have found C. pneumoniae in 6–19% of cases. Evidence of lower respiratory tract infection has been found in 0–18% of the pediatric population.
• Most infections are mild or asymptomatic. Acute infection does not appear to vary by season. A carriage state has been detected in 2–5% of patients. Recurrent infection is common, especially in adults.

» READ BOOK EXCERPT ONLINE »

Source: The 5-Minute Pediatric Consult, 2008

Psittacosis: Psittacosis - epidemiology
(The 5-Minute Pediatric Consult)

• Birds (e.g., pigeons, parrots, parakeets, turkeys, chickens, ducks) are the major reservoir.
• Infecting agent present in bird nasal secretions, urine, feces, feathers, viscera, and carcasses.
• Although inhalation is the most common route of infection, bird bites and mouth-to-beak contact also spread infection.
• Birds may be healthy or sick.
• Most reported cases (70%) are the result of exposure to pet caged birds (especially parrots, parakeets).
• Most common mammalian source of infection is sheep.
• Occupational hazard of workers in poultry plants, pet shops, zoos, farms
• Rarely transmitted person to person

Psittacosis - incidence

• Only 100–200 total cases reported in US each year
• Very rare disease in young children

» READ BOOK EXCERPT ONLINE »

Source: The 5-Minute Pediatric Consult, 2008

About prevalence and incidence statistics:

The term 'prevalence' of Psittacosis usually refers to the estimated population of people who are managing Psittacosis at any given time. The term 'incidence' of Psittacosis refers to the annual diagnosis rate, or the number of new cases of Psittacosis diagnosed each year. Hence, these two statistics types can differ: a short-lived disease like flu can have high annual incidence but low prevalence, but a life-long disease like diabetes has a low annual incidence but high prevalence. For more information see about prevalence and incidence statistics.

Rate This Website

What do you think about the features of this website? Take our user survey and have your say:

Website User Survey

Medical Tools & Articles:

Next articles:

• Videos related to Psittacosis
• Prognosis of Psittacosis
• Causes of Psittacosis
• Risk Factors for Psittacosis
• Symptoms of Psittacosis

Tools & Services:

• Bookmark this page
• Take a survey relating to Psittacosis
• Symptom Search
• Symptom Checker
• Medical Dictionary
• Give your feedback

Medical Articles:

• Disease & Treatments Search
• Misdiagnosis Center
• Full list of interesting articles

Forums & Message Boards

• Ask or answer a question at the Boards:
• I cannot get a diagnosis. Please help.
• Tell us your medical story.
• Share your misdiagnosis story.
• What is the best treatment for my condition?
• See all the Boards.

Enter your search terms Submit search form
Search The Web Search wrongdiagnosis.com