Meningococci are a type of bacteria that cause serious infections. The most common infection is meningitis, which is an inflammation of the thin tissue that surrounds the brain and spinal cord. Meningococci can also cause other problems, including a serious bloodstream infection called sepsis. In its early stages, you may have flu-like symptoms and a stiff neck. But the disease can progress quickly and can be fatal. Early diagnosis and treatment are extremely important. Lab tests on your blood and cerebrospinal fluid can tell if you have it. Treatment is with antibiotics. Since the infection spreads from person to person, family members may also need to be treated.
A vaccine can prevent meningococcal infections.
Meningococci are a type of bacteria that cause serious infections. The most common infection is meningitis, which is an inflammation of the thin tissue that surrounds the brain and spinal cord. Meningococci can also cause other problems, including a serious bloodstream infection called sepsis. In its early stages, you may have flu-like symptoms and a stiff neck. But the disease can progress quickly and can be fatal. Early diagnosis and treatment are extremely important. Lab tests on your blood and cerebrospinal fluid can tell if you have it. Treatment is with antibiotics. Since the infection spreads from person to person, family members may also need to be treated.
A vaccine can prevent meningococcal infections.
The presentation provide in depth knowledge about two of the most affecting bacteria to human health. They are Neisseria ( causing gonorrhea and Meningitis) and Shigella ( Diarrhea)
Streptococcus pyogenes
Streptococcus pyogenes.jpg
S. pyogenes bacteria at 900x magnification
Scientific classification
Kingdom: Eubacteria
Phylum: Firmicutes
Class: Bacilli
Order: Lactobacillales
Family: Streptococcaceae
Genus: Streptococcus
Species: S. pyogenes
Binomial name
Streptococcus pyogenes
Rosenbach 1884
Streptococcus pyogenes is a species of Gram-positive bacteria. These bacteria are aerotolerant and an extracellular bacterium, made up of non-motile and non-sporing cocci. As expected with a streptococci, it is clinically important in human illness. It is an infrequent, but usually pathogenic, part of the skin microbiota. It is the predominant species harboring the Lancefield group A antigen, and is often called group A streptococcus (GAS). However, both Streptococcus dysgalactiae and the Streptococcus anginosus group can possess group A antigen. Group A streptococci when grown on blood agar typically produces small zones of beta-hemolysis, a complete destruction of red blood cells. (A zone size of 2–3 mm is typical.) It is thus also called group A (beta-hemolytic) streptococcus (GABHS), and can make colonies greater than 5 mm in size.[1]
Like other cocci, streptococci are round bacteria. The name is derived from Greek words meaning chain(Strepto) of berries (coccus) and pus(pyo)-forming(genes), because streptococcal cells tend to link in chains of round cells (see image) and a number of infections caused by the bacterium, produce pus. Streptococci are can be catalase positive or negative.[2] S. pyogenes can be cultured on blood agar plates. Under ideal conditions, it has an incubation period of 1 to 3 days.[3]
An estimated 700 million GAS infections occur worldwide each year. While the overall mortality rate for these infections is 0.1%, over 650,000 of the cases are severe and invasive, and have a mortality rate of 25%.[4] Early recognition and treatment are critical; diagnostic failure can result in sepsis and death.[5][6]
Haemophilus is the name of a group of bacteria. There are several types of Haemophilus. They can cause different types of illnesses involving breathing, bones and joints, and the nervous system. One common type, Hib (Haemophilus influenzae type b), causes serious disease. It usually strikes children under 5 years old
The presentation provide in depth knowledge about two of the most affecting bacteria to human health. They are Neisseria ( causing gonorrhea and Meningitis) and Shigella ( Diarrhea)
Streptococcus pyogenes
Streptococcus pyogenes.jpg
S. pyogenes bacteria at 900x magnification
Scientific classification
Kingdom: Eubacteria
Phylum: Firmicutes
Class: Bacilli
Order: Lactobacillales
Family: Streptococcaceae
Genus: Streptococcus
Species: S. pyogenes
Binomial name
Streptococcus pyogenes
Rosenbach 1884
Streptococcus pyogenes is a species of Gram-positive bacteria. These bacteria are aerotolerant and an extracellular bacterium, made up of non-motile and non-sporing cocci. As expected with a streptococci, it is clinically important in human illness. It is an infrequent, but usually pathogenic, part of the skin microbiota. It is the predominant species harboring the Lancefield group A antigen, and is often called group A streptococcus (GAS). However, both Streptococcus dysgalactiae and the Streptococcus anginosus group can possess group A antigen. Group A streptococci when grown on blood agar typically produces small zones of beta-hemolysis, a complete destruction of red blood cells. (A zone size of 2–3 mm is typical.) It is thus also called group A (beta-hemolytic) streptococcus (GABHS), and can make colonies greater than 5 mm in size.[1]
Like other cocci, streptococci are round bacteria. The name is derived from Greek words meaning chain(Strepto) of berries (coccus) and pus(pyo)-forming(genes), because streptococcal cells tend to link in chains of round cells (see image) and a number of infections caused by the bacterium, produce pus. Streptococci are can be catalase positive or negative.[2] S. pyogenes can be cultured on blood agar plates. Under ideal conditions, it has an incubation period of 1 to 3 days.[3]
An estimated 700 million GAS infections occur worldwide each year. While the overall mortality rate for these infections is 0.1%, over 650,000 of the cases are severe and invasive, and have a mortality rate of 25%.[4] Early recognition and treatment are critical; diagnostic failure can result in sepsis and death.[5][6]
Haemophilus is the name of a group of bacteria. There are several types of Haemophilus. They can cause different types of illnesses involving breathing, bones and joints, and the nervous system. One common type, Hib (Haemophilus influenzae type b), causes serious disease. It usually strikes children under 5 years old
STI information with content knowledge of what is important relating to protecting oneself. This is targeted for 16yer old students as teaching support and may contain some graphic pictures.
This week, cerebrospinal meningitis is on the news. This disease, which is majorly prevalent during the dry season has been reported to be ravaging five states in the North-West region of Nigeria including- Zamfara, Sokoto, Kebbi, Katsina and Niger States.
An infection of the central nervous system can be a life-threatening condition, especially for children with weakened immune systems. These infections need ...
Forensic medicine medical negligence 2-bolam principle
Microbiology lec6
1. Medical Microbiology
Systemic bactreiology
Gram +ve cocci
Lecture-7
Dr. Saleh M Y OTH
PhD
Medical Molecular Biotechnology and Infectious Diseases
013/10/2010
IMS - MSU
4. - Causes 60-70% of all bacterial
pneumonias
- Small, lancet-shaped cells
arranged in pairs and short
chains
- Culture requires blood or
chocolate agar
- Growth improved by 5-10% CO2
- Lack catalase and peroxidases
– cultures die in O2 4
5. S. pneumoniae
- All pathogenic strains form large capsules –
major virulence factor
- Specific soluble substance (SSS) varies
among types
- 90 different capsular types have been
identified
- Causes pneumonia and otitis media
5
6. Epidemiology and Pathology
- 5-50% of all people carry it as normal flora in the
nasopharynx; infections are usually endogenous
- Very delicate, does not survive long outside of its
habitat
- Young children, elderly, immunocompromised,
those with other lung diseases or viral infections,
persons living in close quarters are predisposed to
pneumonia
- Pneumonia occurs when cells are aspirated into the
lungs of susceptible individuals
- Pneumococci multiply and induce an overwhelming
inflammatory response
- Gains access to middle ear by way of eustachian
6
tube
9. View of ear anatomy indicating route
of infection
9
10. Cultivation and Diagnosis
- Gram stain of specimen – presumptive
identification
- Quellung test or capsular swelling reaction
- α-hemolytic; optochin sensitivity, bile
solubility, inulin fermentation
10
11. Treatment and Prevention
Traditionally treated with penicillin G or V
Increased drug resistance
Two vaccines available for high risk
individuals:
- Capsular antigen vaccine for older adults and
other high risk individuals – effective 5 years
- Conjugate vaccine for children 2 to 23 months
11
13. Family Neisseriaceae
Gram-negative cocci
Residents of mucous membranes of warm-
blooded animals
Genera include Neisseria, Branhamella,
Moraxella
Two primary human pathogens:
- Neisseria gonorrhoeae (STD)
- Neisseria meningitidis
13
14. Genus Neisseria
- Gram-negative, bean-shaped, diplococci
- None develop flagella or spores
- Capsules on pathogens
- Pili
- Strict parasites, do not survive long outside of the
host
- Aerobic or microaerophilic
- Oxidative metabolism
- Produce catalase and cytochrome oxidase
- Pathogenic species require enriched complex
media and CO2
14
15. Neisseria Gonorrhoeae:
The Gonococcus
Causes gonorrhea, an STD
Virulence factors:
- Fimbriae, other surface molecules for
attachment; slows phagocytosis
- IgA protease – cleaves secretory IgA
15
16. Epidemiology and Pathology
- Strictly a human infection
- In top 5 STDs
- Infectious dose 100-1,000
- Does not survive more than 1-2 hours
on fomites
16
18. Gonorrhea
Infection is asymptomatic in 10% of males and
50% of females
Males – urethritis, yellowish discharge, scarring,
and infertility
Females – vaginitis, urethritis, salpingitis (PID)
mixed anaerobic abdominal infection,
common cause of sterility and ectopic tubal
pregnancies
Extragenital infections – anal, pharygeal,
conjunctivitis, septicemia, arthritis
18
21. Gonorrhea in Newborns
Infected as they pass through birth canal
Eye inflammation, blindness
Prevented by prophylaxis immediately
after birth
21
22. Diagnosis and Control
Gram stain – Gram-negative intracellular
(neutrophils) diplococci from urethral, vaginal,
cervical, or eye exudate – presumptive
identification
20-30% of new cases are penicillinase-producing
PPNG or tetracycline resistant TRNG
Combined therapies indicated
Recurrent infections can occur
Reportable infectious disease
22
24. Neisseria Meningitidis: The
Meningococcus
Virulence factors:
- Capsule
- Adhesive fimbriae
- IgA protease
- Endotoxin
12 strains; serotypes A, B, C cause most
cases
24
25. Epidemiology and Pathogenesis
Prevalent cause of meningitis; sporadic or
epidemic
Human reservoir – nasopharynx; 3-30% of adult
population; higher in institutional settings
High risk individuals are those living in close
quarters, children 6 months-3 years, children
and young adults 10-20 years
25
26. Epidemiology and Pathogenesis …
Disease begins when bacteria enter bloodstream,
cross the blood-brain barrier, permeate the
meninges, and grow in the cerebrospinal fluid
Very rapid onset; neurological symptoms;
endotoxin causes hemorrhage and shock; can
be fatal
26
29. Clinical Diagnosis
Gram stain CSF, blood, or asopharyngeal
sample
Culture for differentiation
Rapid tests for capsular polysaccharide
29
30. Treatment and Prevention
Treated with IV penicillin G, cephalosporin
Prophylactic treatment of family members,
medical personnel, or children in close
contact with patient
Primary vaccine contains specific purified
capsular antigens
30
32. Other Gram-Negative Cocci and
Coccobacilli
Genus Branhamella
- Branhamella catarrhalis – found in nasopharynx:
significant opportunist in cancer, diabetes,
alcoholism
Genus Moraxella
- Bacilli – found on mucous membranes
Genus Acinetobacter
32