Streptococcus pneumoniae

Presented by-Md. Masud Rana

Characteristics First isolated simultaneously and independently by the U.S.

Army physician George Sternberg and the French chemist Louis Pasteur.

Gram-positive, alpha-hemolytic, facultative anaerobic member of the genus Streptococcus.

Major cause of pneumonia in the late 19th century.

Incubation period of pneumococcal pneumonia is short about 1 to 3 days.

Rapidly diagnosed by collecting sputum specimens.

Catalase test negative.

Diagnosis and Identification

QUELLUNG REACTION

Virulence factor

Pneumolysin• Binds cholesterol• Forms pores• Impair phagocytes• Contribute to lung damage

PspA- function unknownSpsA- binds secretory chain of sIgAPsaA- adherence to pneumocytesCbpA- binds choline

Virulence factor

Virulence factor

Capsule• Complex polysaccharide• Anti phagocytic

Cell wall components• Inflammation• Peptidoglycan fragments• Interaction with meninges

Pathogenesis & Disease

Pneumonia

Sign and Symptoms Symptoms of pneumococcal disease depend on the part of the body

that is infected. They can include-• fever• cough• shortness of breath • chest pain• stiff neck• confusion and disorientation• sensitivity to light• joint pain, chills, ear pain, sleeplessness, and irritability.• In severe cases cause hearing loss, brain damage, and death.

Epidemiology

• The African Region has the highest burden of global child mortality • About 45% of global under-5 deaths• 50% of worldwide deaths from pneumonia in this age group• Less than 2% of these deaths take place in the European Region• Less than 3% in the Region of the Americas• More than 90% of all deaths due to pneumonia in children aged less

than 5 years take place in 40 countries• According to the official estimates from WHO for the year 2000, two-

thirds of all these deaths are concentrated in just 10 countries.

Estimated Number Of Deaths

Burden of Pneumococcal infections among under five children Result-• Around 30% of the sample respondents had Pneumonia• 17% had Severe Pneumonia • 26% had been affected by Meningitis• The rest had been suffering from Sepsis• Mother’s higher education level had been linked up with the reduction of

Pneumonia• Mean difference of Nature of fuel used for cooking, weight and weight for age

were significantly differ among children with pneumococcal and non- Pneumococcal infection groups.

Epidemiology In Bangladesh

Risk Factors Risk factors related to the host and the environment that affect incidence of childhood clinical

pneumonia in the community in developing countrieszz

Definite risk factorsMalnutrition Low birth weight (≤ 2500 g) Non-exclusive breastfeeding (during the first 4 months of life) Indoor air pollutionCrowding

Likely risk factorssmokingZinc deficiencyConcomitant diseases (e.g. diarrhoea, heart disease, asthma) 

Possible risk factorsMother’s educationRainfall (humidity)Vitamin A deficiencyOutdoor air pollution

Transmission

Pneumococcal bacteria spread from-o-person-to-person by direct contact with respiratory secretionso-sneezingo-coughingo-Many people have the bacteria in their nose or throat without being

ill. When immune system is impaired the symptoms of infection will manifest.

Prevention and Treatment Antibiotics• Penicillin only for susceptible pneumonia• Some strain multidrug-resistant Vaccine• Capsular vaccine-poorly immunogenic in elder New vaccine-protein conjugated to capsular serotypes Future vaccine--mixture of surface protein-pneumolysin-pspA DNA vaccine

Passive immunization-injection of anti-capsular antibodies from Another source

SHOW IS OVER

Summary-

Please keep your environment clean ,make your generation healthy & wealthy