Other Harmful Microorganisms

In the past, it was believed that bacteria of the Bacillus type spoilt meat, but the specific type was unknown. Van Ermengem discovered that Clostridium botulinum, an anaerobic bacterium, is responsible for food poisoning. Ida Bengston obtained higher education in biochemistry at Chicago University. She conducted important research on the toxin responsible for gas gangrene and the antitoxin useful for treating it. While she was researching the dreaded disease called typhus, she herself contracted the infection. But she overcame it and continued her research. For this work, she was honoured with the ‘Typhus Medal’ in 1947.

Other harmful microorganisms, including bacteria, viruses, protozoa, and fungi, can cause various diseases in humans. These microorganisms are found in our surroundings and can enter the body through air, water, food, or physical contact.

• Viruses, for example, are even smaller than bacteria and have a unique characteristic: they can only grow and reproduce inside the living cells of other organisms. Once inside a host cell, viruses multiply quickly, often damaging or destroying the cell in the process. This can lead to diseases such as the common cold, flu, chickenpox, and more serious illnesses like COVID-19.
• Bacteria, fungi, and protozoa also pose significant risks. While some bacteria are beneficial, others cause infections like tuberculosis and food poisoning. Fungi can lead to skin infections, like ringworm, and protozoa can cause diseases like malaria and dysentery.

These microorganisms, although microscopic, have the potential to harm human health and spread rapidly if proper precautions are not taken. Therefore, maintaining hygiene and following preventive measures is essential to protect ourselves from such harmful microorganisms.

AIDS (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV). It spreads primarily through the blood and semen of an infected person, unprotected sexual contact, sharing contaminated needles, or from an infected mother to her child through breastfeeding or during childbirth. The virus weakens the immune system, making the body vulnerable to various infections and diseases. Preventive measures include practicing safe sexual contact by using protection, avoiding the reuse of needles and injections, ensuring safe blood transfusions, and regular HIV testing to detect infections early.

Hepatitis is caused by various viruses, with the most common being the hepatitis viruses classified as types A, B, C, D, and E. 

Measles is a highly contagious viral disease caused by the measles virus. It spreads through respiratory droplets when an infected person coughs or sneezes or by direct contact with their secretions. Symptoms include high fever, cough, runny nose, red eyes, and red rashes that start on the face and spread to the rest of the body. Preventive measures include vaccination with the MMR vaccine (measles, mumps, and rubella), avoiding contact with infected individuals, and maintaining good personal hygiene. Complications can include pneumonia, ear infections, and encephalitis, which makes early diagnosis and treatment essential.

Measles virus

6. Chickenpox

Chickenpox is caused by the Varicella-Zoster virus (VZV) and spreads through respiratory droplets or direct contact with the fluid from itchy, fluid-filled blisters. It primarily affects children and presents with symptoms like fever, fatigue, and a rash that progresses into blisters, which scab over time. Preventive measures include vaccination with the varicella vaccine, maintaining proper hygiene, isolating infected individuals, and avoiding contact with their belongings. Chickenpox can lead to complications like secondary bacterial skin infections or pneumonia, particularly in immunocompromised individuals, so early medical intervention and supportive care are crucial.

Leprosy, also known as Hansen's disease, is a chronic infectious disease caused by the bacterium Mycobacterium leprae. It primarily spreads through prolonged and repeated contact with an infected person, often via respiratory droplets from coughing or sneezing, though it does not spread easily. The disease affects the skin, peripheral nerves, eyes, and mucosal surfaces of the respiratory tract, leading to symptoms like discoloured skin patches, numbness, muscle weakness, and nerve damage if left untreated. Preventive measures include avoiding prolonged close contact with infected individuals and their personal belongings, practicing good personal hygiene, and raising awareness about early symptoms to reduce stigma. Early detection and treatment with Multidrug Therapy (MDT), provided for free by the World Health Organisation, can completely cure the disease and prevent transmission. Maintaining a healthy immune system through proper nutrition and hygiene can further reduce the risk of infection. 

Cholera is an acute diarrhoeal disease caused by the bacterium Vibrio cholerae, which spreads primarily through the consumption of contaminated food and water. Poor sanitation, unsafe drinking water, and improper food handling are major factors that contribute to its transmission, especially in areas with inadequate infrastructure or during natural disasters. Cholera causes severe watery diarrhoea, dehydration, and electrolyte imbalance, which, if untreated, can lead to death within hours. Preventive measures include consuming clean, safe water, eating properly cooked food, maintaining good hygiene practices such as regular handwashing with soap, and ensuring proper sanitation systems. Boiling water, using water purifiers, and avoiding raw or undercooked food are effective ways to prevent infection. Vaccination is also available for individuals at high risk, particularly in regions where cholera outbreaks are common. Prompt treatment with oral rehydration salts (ORS) and, in severe cases, intravenous fluids and antibiotics can save lives and prevent complications.

1. Dandruff

Dandruff is a common scalp condition caused by the overgrowth of fungi, particularly Malassezia, which feed on excess oil and dead skin cells. It can result in flaky, itchy, and irritated skin on the scalp. Though not contagious, poor personal hygiene, excessive oil production, dry skin, stress, and sensitivity to hair care products can worsen dandruff. Preventive measures include maintaining good personal hygiene, regularly washing the scalp with anti-dandruff shampoos containing ingredients like zinc pyrithione or ketoconazole, and keeping hair and scalp clean. A balanced diet and stress management can also help reduce dandruff.

Malassezia furfur

2. Ringworm

Ringworm, also known as Tinea, is a contagious fungal infection caused by dermatophytes like Trichophyton and Microsporum. It appears as circular, red, scaly patches on the skin, scalp, nails, or feet and spreads through direct contact with infected individuals, animals, soil, or contaminated objects like clothes, towels, or combs. The infection thrives in warm, moist environments. Preventive measures include practicing good personal hygiene, keeping skin dry, avoiding sharing personal items with infected individuals, and disinfecting commonly used objects. Wearing breathable fabrics and properly drying the body after bathing can also help prevent fungal infections.

Trichophyton

3. Scabies

Scabies is a highly contagious skin condition caused by the microscopic mite Sarcoptes scabiei. It spreads through prolonged skin-to-skin contact with an infected person or by sharing belongings such as clothes, towels, and bedding. The mites burrow into the skin, causing intense itching, rashes, and red bumps, particularly in warm areas of the body like between fingers, wrists, and waistlines. Preventive measures include maintaining proper personal hygiene, avoiding close contact with infected individuals, washing clothes and bedding in hot water, and disinfecting shared items.