Exogenous NAD, nicotinamide mononucleotide, or nicotinamide riboside is required for the growth of Haemophilus influenzae. These compounds have been defined as the V-factor growth requirement. We have previously shown that the internalization of nicotinamide riboside is energy dependent and carrier mediated with saturation kinetics. Thionicotinamide riboside, 3-pyridinealdehyde riboside, 3-acet...

Haemophilus influenzae type b is the leading cause of meningitis in children younger than 5 years of age in the United States. The incidence of infection with H influenzae type b in certain populations, such as Apache and Navajo Indians and Alaskan Eskimos, is 10 to 20 times higher than in the general US population. Another important feature of H influenzae type b infections in these population...

Conjugation: Although H. influenzae genes may be transferred by plasmid-mediated conjugation, this process is not discussed further below as it has received little attention and is rarely used for strain construction. Conjugative plasmids are common in H. influenzae as in other bacteria [1, 2, 3]. The F plasmid of Escherichia coli can conjugate into H. influenzae cells [4] (and into many other ...

had not been given to contacts of these patients, but only one of the "secondary" cases occurred within 30 days of the index case; the others were two months and three months apart. Although rifampicin prophylaxis is of limited value, the relatively poor compliance with the current recommendations suggests that its value is commonly reduced even further by incorrect use. There has been concern ...

To obtain more information on the much-debated definition of prokaryotic species, we investigated the borders of Haemophilus influenzae by comparative analysis of H. influenzae reference strains with closely related bacteria including strains assigned to Haemophilus haemolyticus, cryptic genospecies biotype IV, and the never formally validated species "Haemophilus intermedius". Multilocus seque...

We report on a case of spontaneous bacterial peritonitis (SBP) due to Haemophilus influenzae (H. influenzae) in an elderly patient with alcoholic cirrhosis. The patient presented with a 5 day history of fever, cough, and fatigue. Abdominal paracentesis revealed a very high neutrophil count (134,800 cells/μL). Secondary peritonitis and abdominal abscess were ruled out. Peritoneal fluid culture d...

Haemophilus influenzae is a commensal of the human upper respiratory tract. H. influenzae can, however, move out of its commensal niche and cause multiple respiratory tract diseases. Such diseases include otitis media in young children, as well as exacerbations of chronic obstructive pulmonary disease (COPD), sinusitis, conjunctivitis, and bronchitis. During the course of colonization and infec...

We describe the epidemiology of invasive Haemophilus influenzae disease during 2007-2014 in 12 European countries and assess overall H. influenzae disease trends by serotype and patient age. Mean annual notification rate was 0.6 cases/100,000 population, with an increasing annual trend of 3.3% (95% CI 2.3% to 4.3%). The notification rate was highest for patients <1 month of age (23.4 cases/100,...

Encapsulated Haemophilus influenzae is a causative agent of invasive disease, such as meningitis and septicemia. Several interactions exist between H. influenzae and the human host. H. influenzae has been reported to bind IgD in a nonimmune manner, but the responsible protein has not yet been identified. To define the binding site on IgD for H. influenzae, full-length IgD and four chimeric IgDs...

Strains of nontypeable Haemophilus influenzae show enormous genetic heterogeneity and display differential virulence potential in different clinical settings. The igaB gene, which encodes a newly identified IgA protease, is more likely to be present in the genome of COPD strains of H. influenzae than in otitis media strains. Analysis of igaB and surrounding sequences in the present study showed...