Related Experiment Video

Updated: Aug 9, 2026

Humanized Mouse Model to Study Bacterial Infections Targeting the Microvasculature
11:40

Humanized Mouse Model to Study Bacterial Infections Targeting the Microvasculature

Published on: April 1, 2014

Outbreak of meningococcal disease caused by PorA-deficient meningococci

A van der Ende1, C T P Hopman, W C M Keijzers

  • 1Department of Medical Microbiology, Academic Medical Center, PO Box 22700, 1100 DE Amsterdam, The Netherlands. a.vanderende@amc.uva.nl

The Journal of Infectious Diseases
|February 25, 2003
PubMed

Insights

Transmission of PorA-deficient meningococci can cause invasive disease, as seen in a Dutch outbreak. This finding suggests that PorA-based vaccines may offer limited protection against meningococcal disease.

Area of Science:

  • Microbiology
  • Epidemiology
  • Vaccinology

Background:

  • Group C meningococcal disease outbreaks pose a significant public health risk.
  • Neisseria meningitidis expresses PorA outer membrane proteins, a common target for vaccines.
  • The role of PorA-deficient meningococci in disease transmission and severity is not fully understood.

Purpose of the Study:

  • To investigate the characteristics of meningococcal isolates during an outbreak in The Netherlands.
  • To determine if PorA-deficient meningococci can be transmitted and cause invasive disease.
  • To assess the potential impact of PorA deficiency on the efficacy of PorA-based vaccines.

Main Methods:

  • Epidemiological data collection from a 2001 outbreak in southwestern The Netherlands.
  • Molecular characterization of seven group C Neisseria meningitidis isolates using various typing methods.
  • Analysis of PorA expression in patient isolates.

Main Results:

  • Seven identical group C meningococcal isolates were identified, differing only in PorA expression.
  • Isolates from five out of seven patients were found to be PorA deficient.
  • The study confirmed the transmission and invasive potential of PorA-deficient meningococci.

Conclusions:

  • PorA-deficient Neisseria meningitidis can be transmitted between individuals.
  • PorA-deficient meningococci are capable of causing invasive meningococcal disease.
  • Current PorA-based meningococcal vaccines may have limited effectiveness against PorA-deficient strains, necessitating further vaccine development.

More Related Videos

Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria11:32

Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria

Published on: February 23, 2014

Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery10:03

Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery

Published on: November 5, 2019

Related Concept Videos

Rocky Mountain Spotted Fever01:26

Rocky Mountain Spotted Fever

Rocky Mountain Spotted Fever (RMSF) is a severe tick-borne illness caused by Rickettsia rickettsii, a Gram-negative, coccobacillary bacterium. This pathogen is an obligate intracellular parasite, requiring a host cell for replication. Transmission occurs through the bite of an infected tick. In the United States, the most important vectors are Dermacentor variabilis (American dog tick) and Dermacentor andersoni (Rocky Mountain wood tick), though other tick species may also serve as vectors.
Bacterial Meningitis01:24

Bacterial Meningitis

Bacterial meningitis is a severe infectious disease involving inflammation of the meninges, the protective membranes surrounding the brain and spinal cord. It occurs when pathogenic bacteria cross the blood–brain barrier and enter the cerebrospinal fluid. Common causative organisms include Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b, Listeria monocytogenes, and Escherichia coli K1. The exact route of entry varies by pathogen and host condition.Routes of Entry...
Viral Meningitis01:18

Viral Meningitis

Viral meningitis is the most common form of meningitis and is often referred to as aseptic meningitis to indicate the absence of bacterial involvement. It is generally milder than bacterial meningitis, with symptoms including fever, headache, stiff neck, drowsiness, nausea, photophobia, and vomiting. Rarely, more severe manifestations or death may occur. Common causative agents include enteroviruses, particularly coxsackie A and B viruses and echoviruses, all members of the Enterovirus genus...
Cryptococcal Meningitis01:27

Cryptococcal Meningitis

Cryptococcal meningitis is a life-threatening opportunistic infection predominantly associated with HIV/AIDS, accounting for over 100,000 deaths annually worldwide. However, it also affects individuals with other forms of immunosuppression, including those undergoing immunosuppressive therapy, organ transplant recipients, patients with innate immunodeficiencies, and individuals with hematological disorders. The infection is caused mainly by Cryptococcus neoformans and Cryptococcus gattii,...
Bacterial Meningitis I: Introduction01:22

Bacterial Meningitis I: Introduction

Bacterial meningitis is a severe, life-threatening inflammation of the meninges, particularly the pia mater and arachnoid mater, affecting the subarachnoid space, ventricles, and cerebrospinal fluid (CSF). If untreated, it can lead to significant neurological complications or death.Causative AgentsCommon pathogens vary with age and immune status. In adults, major organisms include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. Streptococcus agalactiae (group B...
Bacterial Meningitis II: Pathophysiology01:26

Bacterial Meningitis II: Pathophysiology

Bacterial meningitis typically begins when pathogens such as Neisseria meningitidis and Streptococcus pneumoniae colonize the nasopharynx and invade the bloodstream. This process is facilitated by bacterial virulence factors, such as polysaccharide capsules, which resist phagocytosis and complement-mediated killing. Less commonly, bacteria reach the central nervous system via contiguous spread from infections like otitis media or sinusitis, through congenital or acquired dural defects, or...