Bacteria are prokaryotic microorganisms that are ubiquitous i.e they are found everywhere. They exist in different shapes such as cocci (round shaped), bacillus (rod shaped), spirilla (spiral shaped) and vibro (coma shaped). Bacteria posesses different survival mechanisms. There are different temperature ranges at which bacteria survive, some can only survive at extreme cold temperature hence, they are called “psycophiles” ,the ones that survive at moderate temperature such as human body temperature are called “mesophiles” while those that can only thrive in hot temperature are called “thermophiles”. Some bacteria can only survive in the presence of oxygen hence they are called “aerobic bacteria” while those that thrive without the presence of oxygen are called “anearobic bacteria”.
Some bacteria are beneficial to human body while others are extremely harmful, dangerous and infectious. In today’s article we will be highlighting the different types of harmful and infectious bacteria that threatens human health.
What are pathogenic bacteria?
Pathogenic bacteria refer to harmful bacteria that are capable of causing infections. They can invade the body through different mediums and cause illnesses. Some bacteria can affect the surface of the body and cause skin infections while others can be foodborne or airborne bacteria. You can also get some bacterial infections through sexual contact, from mother to child through birth and through contact with contaminated surfaces.
Most harmful bacteria and known for their antibiotic resistance. They are not easily killed by taking antibiotics and in most cases it requires combination of several antibiotics to effectively eliminate them. Bacteria antibiotics resistance is a life-threatening condition and they are often caused by misuse of antibiotic drugs.
The 7 harmful and highly infectious bacteria that threatens human health include:
This is a non-motile rod shaped bacteria that causes the infection called tuberculosis. It is an acid-fast organism that do not retain gram stains but instead it can only be identified by using an acid-fast staining technique.
Tuberculosis is a life-threatening disease that affect the lungs and may spread to other part of the body such as brain, abdomen, urinary tract, bones and joint. Tuberculosis is an airborne disease and a person gets infected when he or she inhales a respiratory droplets that contains mycobacterium tuberculosis. People who are more likely to get infected with tuberculosis include public health workers, caregivers, prisoners, people with compromised immune system such as diabetes, HIV and cancer patients, drug abusers, infants, teens, adults and people who are malnourished.
Tuberculosis is one of the leading cause of death globally because of the horrible symptoms they bring up and their antibiotic resistance. However there is a vaccine called BCG (Bacille Almette- Guerine) that is used to prevent tuberculosis but it is not commonly used in United States. According to CDC BCG does not always protect people from getting infected with tuberculosis. Therefore, precautionary measures to prevent the transmission of tuberculosis such as wearing of masks, regular handwashing and correct usage of prescription drugs should be practiced.
This is a gram-negative non-motile rod shaped bacteria. They are commonly found in the intestine without causing infection. However, they can cause series of infections when they spread to other parts of the body. The infection they cause depend on their location in your body, they include:
- Skin infection: when klebsiella pneumonia invade the skin, they can cause skin infection or wound infection such as myositis and cellulitis.
- Meningitis: it occurs when klebsiella pneumonia affect the brain
- Urinary tract infection: you can get urinary tract infection when K. pneumonia enters and affect your urinary tract such as urethra, urether, bladder and kidney.
- Bacteremia: it occurs when K. pneumonia causes blood infection
- Pyogenic liver abscess: it happens when K. pneumonia attacks and causes inflammation to the liver.
Klebsiella pneumonia usually spread through human-to-human contact especially with an infected person. It can also be spread through contaminated medical equipment such as ventilators and catheter. People who are more likely to get K. pneumonia infections are those with weakened immune system such as those with diabetes, chronic liver disease, cancer and kidney failure, individuals that are addicted to alcohol and people that are hospitalized and kept on ventilators. Klebsiella pneumonia infections are very difficult to treat because of their high resistance to antibiotics.
It is a gram positive round shaped bacteria that is commonly found in the upper respiratory tract (nose) or on the skin. It can become a life-threatening disease when they invade other part of the body and cause infections. Depending on their location in the body they can cause the following infections:
- Bacteremia: Staph aureus can invade the bloodstream and cause serious infections to it
- Skin infections: when staph aureus affect the skin they can cause infection such as cellulitis, impettigo and boils.
- Infectious arthritis: Staph aurues can affect the joints in the body and cause inflammation, swelling and redness. They can affect the fingers, shoulder, knees and other joints in the body.
Staphylococcus aureus infections can be spread by coming in contact with an infected person or by direct contact with infected blood or other bodily fluids. This bacteria are mostly resistant to many antibiotics and extremely difficult to cure with treatment. The common example is methicillin-resistant staphylococcus aureus infection.
This is another harmful bacteria, it a gram-negative rod shaped bacteria that causes nosocomial infection. Nosocomial infections are diseases that are acquired in an hospital environment. Pseudomonas aeruginosa can affect different part of the body and cause infection. They can cause blood infection (bacteremia), skin infections (mostly wound infection), ear infections, lung infections (pneumonia), eye infections and osteomyelitis.
People who are mostly susceptible to Pseudomonas aeruginosa infections include immunocompromised patients such as those taking chemotherapy, HIV and AIDs patients, individuals with wounds, people who are hospitalized and kept on ventilators, people undergoing surgeries and those using catheter. Pseudomonas aeruginosa infection is a disease that threatens the continuity of life because of its high resistance to antibiotics and treatment may involve combinations of many antibiotics which may be too expensive to afford.
It is a gram-positive anaerobic rod shaped bacteria that causes a deadly infection called tetanus. Tetanus is a serious health condition that affect the nervous system thereby leading to jaw and muscle contractions. The common symptoms include spasm, jaw and muscle stiffness, extreme difficulty in breathing and swallowing, fever, irregular heartbeat and high blood pressure. Clostridium tetani are mostly found in the soil and can get into the body through wounds, cuts, punctures and burns. It is important to note that there is no known cure for tetanus infection, the best way to prevent this infection is by ensuring appropriate wound care and getting vacinated against the disease.
Shiga Toxin producing E. coli (STEC)
This is a kind of E. coli that targets, attacks and affects the gastrointestinal tract. It causes a severe foodborne illness and the common symptoms include nausea, vomiting, abdominal pains and bloody diarrhoea. You can get the infection by eating foods or drinking water contaminated with the bacteria, you can also get the infection through direct contact with an infected person. This disease can be treated and cured with antibiotics. STEC infections can be prevented by proper handling and cooking of foods, maintenance of personal hygiene, drinking of clean and treated water and regular hand-washing with soap and water.
It is a gram-negative rod shaped bacteria that causes sexually transmitted diseases. They can be spread through sexual contact such as oral, anal or vaginal sex with an infected person. They may also be spread from mother to child during child. They can affect the throat, eyes, anus, urethra , penis and female reproductive system such as vigina, cervix and uretus.
Neisseria gonorrhea can cause life-long damage to the body when they are left untreated. However, they can be treated and cured with quality antibiotics. The best way to prevent yourself from getting gonorrhea is by abstaining from sex or by practicing safe sex with the use of latex condom.