Introduction to Bacterial Diseases
Understanding bacterial diseases and their prevention is of utmost importance, as bacterial diseases pose a significant threat to human health. They are responsible for causing a wide array of infections worldwide. This article aims to provide a solid foundation in the realm of bacterial diseases by discussing the underlying mechanisms that allow bacteria to thrive, invade host tissues, and cause diseases. It is important to study the diagnostic techniques, ways to identify these pathogens, and how to combat bacterial infections in the most efficient manner.
List of Bacterial Diseases
- Typhoid / Enteric fever
- Pneumonia
- Cholera / Haiza
- Tuberculosis
- Tetanus / Lock Jaw
- Plaque
- Pertusis (kali khansi)/ Whooping cough
- Leprosy / Kustha rog
- Anthrax
- Meningitis
- Diptheria / galghotu
Typhoid Disease: Causes, Symptoms, and Treatment
Typhoid is a bacterial disease caused by the bacterium Salmonella typhi. It is also known as enteric fever or intestinal fever. This disease is associated with the story of Mary Mallon, who worked as a cook for the family in New York. She spread the disease to many people and unfortunately, some people even died of the disease. After investigation, it was found out that Mary Mallon was responsible for spreading the disease in families where she worked as a cook.
Mary Mallon was the carrier of the typhoid bacteria, which is why she did not exhibit any signs or symptoms of the disease. However, being a carrier, she had the potential to spread the disease through the food she prepared at the restaurant. Consequently, she was advised against working as a chef in any restaurant or family due to this concern. Mary Mallon is commonly known as Typhoid Mary.
How the Disease is spread?
The typhoid causing bacteria enter the human body by the fecal-oral route through undercooked food, contaminated water, and fomites of infected patients. It is more common in overcrowded areas with poor sanitation. Transmission occurs from one infected person to another. Humans are the only host of this disease.
Signs and Symptoms of Typhoid
- High fever with low pulse rate
- Patients experience abdominal pain and pass frequent stools
- In certain cases, there could be intestinal perforation, which results in bleeding
Test / Treatment
- Incubation period could be between 1 and 3 weeks
- Confirmation of the disease is done by Widal test
- Typhoid vaccine is available
- Patient is treated with antibiotics such as Terramycin and Chloromycetin
Pneumonia: Causes, Signs and Symptoms, and Treatment
Pneumonia is a bacterial disease that infects the lungs or respiratory tract. The causative agent of pneumonia could be Streptococcus pneumoniae and Haemophilus influenzae. The word ‘pneumonia’ has its origin from the Greek word “pneumon,” which means lung and thus the word pneumonia becomes lung disease. Though pneumonia could be caused by bacteria, viruses, fungi and parasites, but this article focuses on bacterial pneumonia only.
Causes of Pneumonia
It is caused by the inflammation of the lungs parenchyma. The lower respiratory tract of the lungs is not sterile rather it is exposed to environmental pathogens. If the pneumonia causing bacteria invade and propagate into lung parenchyma at the alveolar level, it causes bacterial pneumonia. This hampers the gas-exchange between alveolar wall and the blood capillary surrounding it.
Mode of Transmission
- The disease spreads by sputum of the infected patient
- Incubation period is 1 to 3 days
Signs and Symptoms
- Lymph, mucus and dead WBC’s collect in the alveoli and bronchioles
- Exchange of gases does not take place in the alveoli and sometimes leads to cyanosis (skin turns bluish)
Cholera / Haiza — Symptoms and Causes
Cholera is a bacterial disease caused by Vibrio cholera. It is also known as Haiza in Hindi. Robert Koch discovered cholera for the first time. However, John Snow was the first to demonstrate that cholera is transmitted by contaminated water. Incubation period varies between 1 and 3 days.
Signs and Symptoms
- Frequent stools are passed by patients in the form of white like rice water plus repeated vomiting is seen.
- Diagnosis is performed by microscopic examination of the stool or the vomit where the typical comma-shaped vibrios can be seen.
- ORS (Oral Rehydration Solution) is given to balance the fluid loss from the body
- Drugs such as tetracycline and chloramphenicol are used for the treatment of cholera.
Tuberculosis (TB) — Causes, symptoms and treatment
Tuberculosis is a bacterial disease caused by Mycobacterium tuberculosis. It is also called as Koch’s disease. The bacteria release a toxin called tuberculin in the tissues, which produces the disease. It affects the lungs, lymph nodes, bones and joints. Incubation period is quite variable for this bacterial infection.
Mode of infection
- Transmits through inhalation of droplets expelled by TB patients
- Through consumption of contaminated food or drinks including milk from a TB animal
Symptoms of Pulmonary tuberculosis
- Fever
- Cough
- Blood containing sputum
- Pain in the chest
- Loss of weight
- Hoarseness of throat
- Night sweating and rapid pulse
Prevention and Treatment
- Diagnosis of TB is done by MANTOUX TEST
- BCG (Bacillus Calmette – Guerin) is a vaccine against TB
- While coughing, patients should cover the mouth with a handkerchief
- Tuberculosis is curable
- DOTS (Directly Observed Treatment Short Course) is strategy designed by WHO to ensure cure of the disease
- Streptomycin, and Rifampicin drugs are used for the treatment of TB
Tetanus disease — Symptoms and causes
- It is a bacterial disease caused by Clostridium tetani.
- Tetanus is also called as Lock Jaw disease or Dhanustamba in Hindi
- Pathogens live in the intestine of many domestic animals including horses (without posing any harm) and its spores come out with the excreta of the host
- Spores are highly resistant and can survive for many years
Mode of Infection
- Spores can enter the body through wounds and cuts
- Spores release active bacteria inside the body and later multiply rapidly and secrete exotoxin known as TETANOSPASMIN
Signs and Symptoms
- Headache, irritability followed by back pain, stiff neck and jaw spasm. Ultimately, there is lock jaw, spasm of chest, abdomen and spine
- Death occurs due to suffocation and heart failure
Treatment
- Injection of ATS (Anti Tetanus Serum) gives passive immunity (antibodies are injected) and Tetanus toxoid (inactive toxin) provides active immunity
Plague — Symptoms and causes
- It is a bacterial disease caused by Pasturella pestis / Yersinia pestis
- It is also called as Black Death
- Plague is a disease of rodents, humans get infected by chance
- Wild rat Tatera indica is the reservoir
- It is spread by rat flea Xenopsylla cheopis (from one rat to another). However, when rat dies, the flea leaves the body of the dead rat and if any man come across, it bites and inject the plague bacteria
- Plague is a nature’s way of controlling the population of rats
- The bubonic type of plague (infects lymph nodes) is not transmitted from one man to another but always from a rat to one or more men.
Signs and symptoms
- Swelling of lymph nodes
- Fever
- Headache
- Chills
- Extreme tiredness
Treatment
- Antibiotics such as tetracycline, streptomycin are given
Pertussis — Whooping Cough
- It is also called as Whooping cough or Kaali Khansi in Hindi
- It is caused by Bordetella pertussis
- It is an infection of the upper respiratory tract
- When a person coughs, he or she produces sound like barking of a dog (sometimes called Kutta Khanshi)
- There is cough, fever, vomiting, cyanosis (skin turns bluish)and even bleeding from nose occurs
- Vaccine is available in the form of D.P.T (Diptheria, Petussis, Tetanus) — triple vaccine
Diptheria — Symptoms and causes
- It is also called as Galghotu in Hindi
- It is caused by Cyanobacterium diptheriae
- This disease is found in children up to five years of age
- There is a formation of a pseudo-membrane in the throat which blocks the throat
- Bacteria produces a powerful toxin called diptherotoxin which ruptures mitochondrial membrane of macrophages
- Death occurs within few days
- Life of the patient can be saved if diphtheria antitoxin is given within 48 hours
Meningitis — Symptoms and causes
- It is a bacterial disease caused by Neisseria meningitidis or haemophilus influenza
- There is inflammation of meninges of the brain
- Symptoms include headache, stiffness of neck and vomiting
Leprosy (kustha rog) — Symptoms and treatment
- It is a bacterial disease caused by Mycobacterium leprae.
- This disease was first discovered by Hansen and thus also called as Hansen’s disease
Symptoms:
- Appearance of light colored patches on the skin.\
- Thickening of the nerves
- Partial or total loss of sensation in the affected parts of the body
Mode of infection
- The bacilli leave the body through nasal discharge, from the throat during coughing, and sneezing
Treatment
- The patient is treated with DDS (diamino diphenyl sulphone)
Anthrax — Symptoms and causes
- It is a bacterial disease caused by Bacillus anthracis
- It occurs naturally in soil and commonly affects domestic and wild animals around the world
- People get infected if they get in touch with the infected animals
- Infection occurs through spores and once they reach inside the body, spores form bacteria that multiply rapidly, spread and produce toxins that cause illness.
Human Health and Disease: Bacterial diseases by Dr. Sachin Kapur Sir