Bartonella
A genus of tiny gram negative bacilli. The pathogenic species include:

Bartonella bacilliformis – causing oroya fever
Bartonella henselae – causing cat scratch disease
Bartonella quintana – causing trench fever

They are usually transmitted by arthropods.

Haemophilus influenzae in blood agar
Pfeiffer’s bacillus is Haemophilus influenzae. It is also known as influenza bacillus. It is a small gram negative bacillus first observed by Pfeiffer in 1892. It causes meningitis and acute respiratory infections.

There are a group of diseases that occur in various endemic foci around the world. They are are associated with poor hygiene. They are spread by body contact. They vary in their clinical manifestations. They are difficult to distinguish from syphilitic treponemes. 
The 3 main types of nonvenereal treponematosis are:

Endemic syphilis – caused by Treponema pallidum endemicum
Yaws – T. pallidum pertenue
Pinta – T. pallidum carateum

It is a non tuberculous mycobacteria belonging to the group ‘photochromogens’ and is the causative factor for swimming pool granuloma. It is similar to M.kansasii.
Differentiating features of M.marinum from M.kansasii

Poor growth at 37C
nitratase negative
pyrazinamide hydrolase positive
L- fucosidase positive

It is the group of non tuberculous mycobacteria forming Group I of Runyon’s Classification of non tuberculous mycobacteria. 
Features:
They do not form pigment when kept in the dark. But when a young culture is exposed to light in the presence of air for one hour and later incubated for 24-28 hours, they produce a yellow orange pigment. Their rate of growth is slow, but is faster than that of Mycobacterium tuberculosis.
Members of photochromogens include M.kansasii, M.marinum, M.simiae.

Swimming pool granuloma also known as fish tank granuloma  is a disease caused by Mycobacterium marinum. It is a type of non tuberculous mycobacteria belonging to the group ‘Photochromogens’ in Runyon’s Classification. It manifests as a warty skin lesion.

Photochromogens
Scotochromogens
Nonphotochromogens
Rapid growers

In the natural resorvoir hosts, leptospira does not produce any manifestations. When humans come into contact with water polluted with the  urine of resorvoir hosts, leptospira enter the body through abrasions in skin or through intact mucous membranes of nose, mouth or conjunctiva.
The incubation period is about 10 days (range –  2-26 days). Manifestations can range from mild fever to severe illness with hepatorenal damage (Weils disease). Symptoms include rigors, vomiting, headache and intense congesion of eyes. Jaundice may be present in 10-20% cases by second or third day. Fever …

It refers to the transient inflammatory response seen when administration of antibiotics results in large scale killing of microorganisms and release of endotoxins. The rate of release of endotoxins is much greater than the rate at which the body can detoxify them. This results in manifestations such as fever, myalgia, headache. 
eg: may be found during treatment of syphilis, leptospirosis

Plague being a bacterial disease, responds to the following antibiotics, especially if adminstered early in the course of the disease:

streptomycin
doxycycline
cholramphenicol