The Deadliest and Most Horrible Diseases That Shock the World

You may have read on my previous articles on The most horrible diseases ever to tremble the world, The most horrible diseases ever to tremble the world 2 (or “weirdest and horrible diseases you never seen before”),  The most horrible diseases ever to tremble the world 3 (which presents you some bizarre, odd and unbelievable tumors), and The Most horrible diseases ever to tremble the world 4 (somewhat unusual: The Most Disturbing Deformations and Abnormalities in Human History) and now this article is the fifth series of these dreadful and horrible diseases. In this series, I’ll focus on some highly contagious viruses that cause deadliest and horrible diseases.

Viruses are microbes that are smaller than any bacteria. Typically, viruses are composed of a core of either RNA or DNA surrounded by a protein coat. Tobacco mosaic virus (TMV) for example, consists of one single long RNA molecule (6,000 nucleotides) surrounded by a cylindrical protein coat (2130 pieces of the same coat protein), while T4 bacteriophage consists of a DNA molecule which is tightly packed into one protein head.

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These viruses cause a number of diseases in humans, and they’re found to be a main culprit for diseases such as the common cold, rabies, Ebola, hanta fever, herpes, shingles, influenza, rabies, H1N1, AIDS, HPV, polio, smallpox, SARS and etc.

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Outside the host cells, they exist as capsid, a protein coat or sometimes enclosed within a membrane. They rely very much on the infected host cells to reproduce by inserting their genetic entities into the host. Simply put, they take over the host’s function by instructing the infected cells to produce more genetic material and viral protein. Some viruses are observed to embed their genomes into the DNA of the host cell and are replicated along with the host cell’s DNA or they may remain dormant inside host cells for longer periods without creating any significant change in the host cells (also known as the lysogenic phase), while in a stage of lytic phase, new viruses are created, and later, they burst out of the host cell to both kill and infect other surrounding cells.

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Since these viruses are good “genetic engineers”, they’re able to replicate by incorporating some genetic materials from their hosts, before transferring the genetic information to a new host via a stage called transduction.

HPV

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Human papillomavirus virus (HPV) is sexually transmitted via genital contact (such as anal and oral sex or rubbing through vaginal with a partner who already has HPV) or it may be passed on through skin-to-skin sexual contact. There are more than 100 strains of HPV with about 13 high-risk strains which include type 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68 and 69 that are linked closely with cervical cancer. Of all its strains, type 16 and 18 are reported to cause about 90% of cervical cancers in women worldwide and 200,000 deaths each year. Presently, there is no cure for HPV.

The genital warts  can form a cauliflower-like shape and may also be flat and are normally found on the inside and the outside of the vagina, particularly in a women’s cervix which can be precancerous and cancerous conditions of the cervix. The warts may also be seen in or around the urethra, anus and sometimes the mouth, lips, tongue and throat. In men, they usually appear on the penis, but they can also found on the scrotum or around the anus. Only in some rarely cases, growths are found in the mouth or the throat. If allow to grow, these warts can block the openings of the vagina, urethra, anus, interfering with urination, and they can cause sores, and bleeding (quoted from my previous article entitled why HPV is said to be more dangerous and threatening than SARs?)  Click here and here to see photos of two examples of HPV infections.

Influenza Flu

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In human history, Spanish flu was reported to kill 20 to 100 million lives worldwide. The Spanish flu is the worst killer plaque since it took away 50 million lives in several months and 25 million lives in as short as 25 weeks.

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When influenza viruses from different species infect poultry, two (or more) influenza viruses can undergo “genetic reassortment” (a process in which influenza viruses exchange genes during replication) to emerge as a new virus that is a mixture of two or more species of influenza viruses. These viruses were the basis for the outbreak of the human flu pandemics in 1957 (the “Asian” flu which caused about 2 million deaths) and 1968 (the “Hong Kong” flu which caused about 1 million deaths), which were a result of reassortment viruses with genes from both avian and human influenza viruses.  These pandemic viruses were responsible for tens of thousands of human deaths and million cases of human illnesses (quoted from my previous article entitled Three Scary Killer Flu Pandemics That Raged Fiercely Over the World).

AIDS/HIV

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HIV, or scientifically known as Human Immunodeficiency Virus, is a type of virus that attacks the cells of living organisms by making new copies from the original “codes” (means they make up the human body and replicate within those infected cells), weakening immune system (a natural defence against disease), while attacking a particular immune system cell called CD4 lymphocyte. When the immune system is weakened, it leads to chronic and progressive illness. The HIV then advances to a stage of illness called AIDS, or Acquired Immunodeficiency Syndrome, causing the infected individuals vulnerable towards other infections and illnesses. Some HIV-infected people may look like as ordinary people without showing any significant symptoms. The AIDS virus in their bodies will continue to damage the immune system causing relatively vulnerable defense ability towards diseases. This condition in turns may cause damage in the parts of brain, lungs, and gastrointestinal tracts. As AIDS is regarded as an opportunistic disease, it may also lead to death (quoted from my previous article entitled understanding AIDS/HIV: unveiling the hidden facts and little known facts about AIDS).

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AIDS is a silent killer which has taken million lives worldwide, and up to now, there’s still no cure for AIDS.

H1N1

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Swine flu (also called swine influenza, influenza A (H1N1), or flu) is an acute respiratory disease among the pig populations caused by a tiny spheroid virus that belongs to the Influenza A virus group (source).

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The current cases of swine flu involve the H1N1 strain of type A influenza virus. Its outbreak normally occurs in the colder weather months (late fall and winter) and sometimes with the introduction of new pigs into susceptible herds. Four main influenza type A virus subtypes of H1N1, H1N2, H3N2 and H3N1 have been isolated in pigs; however, the current isolated influenza viruses from swine have been identified as H1N1 viruses (quoted from my previous article entitled swine flu sweeps across the globe: will it be the seventh killer plaque in history?) To date, H1N1 viruses had claimed lives in Mexico, America, Europe and Asian countries.

MRSA

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MRSA (Methicillin-resistant Staphylococcus aureus) is a strain of staph caused by Staphylococcus aureus bacteria. People have a higher possibility to get infected with MRSA viruses at the hospitals or other health care settings (such as at the dialysis center, the nursing home) as well as via a medical procedure (such as surgery, dialysis or catheters) which normally cause soft tissue infections, skin infections (appear as red bumps that resemble spider bites, pimples or boils), severe infections (such as bloodstream infections, surgical wound infection), other body part infections (such as in heart valve, lungs, bone and bloodstream) and/or a severe stage of pneumonia. People with weakened immune systems are particularly at higher risk of MRSA (also called HA-MRSA, CA-MRSA or health care associated MRSA).

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More than 7,000 cases of MRSA bloodstream infections are recorded each year although specialists blame the bug for three times that number of serious infections, with at least 5,000 deaths (source). Read full story written by Triond’s writer, Judy Sheldon, which entitled more deadly than AIDS.

SARS

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SARS (Severe Acute Respiratory Syndrome) is a respiratory disease caused by the SARS coronavirus (SARS-CoV) and this flu pandemic appeared to first hit Guangdong Province, China in November 2002. In March 2003, CDC and WHO issued a global alert as SARS was observed to spread rapidly from China to Hong Kong and later to other countries around the world. The outbreak of SARS alarmed people’s fear towards the emergence of chronic pneumonia, which was reported to claim many lives. SARS generally portrays an initial flu-like symptom and may also include symptoms like myalgia, gastrointestinal symptoms, sore throat, fever (above 38 degree Celsius), lethargy, shortness of breath and other non-specific signs.

Ebola

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Ebola is a life-threatening disease caused by infection with Ebola virus, which was first identified in 1976 in the Ebola River of the Democratic Republic of the Congo (formerly Zaire) in Africa. Up to now, four species of Ebola viruses have been identified, with species of Ebola-Ivory Coast, Ebola-Sudan, and Ebola-Zaire cause diseases in humans, while Ebola-Reston can cause disease in non-human primates.

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Ebola is substantially fatal to humans as the virus invades human cells by causing severe internal bleeding and acute Ebola hemorrhagic fever (Ebola HF) which can kill the infected people. The Ebola virus can be transmitted easily either through contact with skin, mucous membrane, bodily fluids of infected persons or by airborne particles.

Smallpox

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For over 30 centuries, smallpox viruses had existed as fatal pathogens but today, the vaccination had completely eradicated this first global infectious disease. In the past, smallpox ravaged furiously with sporadic outbreaks occurred primarily in developing countries. Smallpox is believed to originate from India or Egypt over 3,000 years ago, and it’s one of the epidemics that have damaged human’s life. Smallpox virus is known to transmit by contaminated bedding and clothes of the infected persons and it can also be transmitted via direct contact with infected bodily fluids or prolonged face-to-face contact with the infected persons.

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Human cells which are infected with variola viruses (a member of the orthopoxvirus family) of smallpox are potentially fatal and highly contagious if vaccination is not given to defend against the smallpox viruses. In history, it was recorded that smallpox had killed King Louis XV (France), King Luis I (Spain), Emperor Joseph I (Spain), Queen Mary II (England), Queen Ulrika Elenora (Sweden), AND Tsar Peter II (Russia).

West Nile Virus

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The West Nile Virus (WNV) was first emerged in the Western Hemisphere in 1999. Since then, it swept across the 48 continental states of the North American continent. According to CDC, about 15,000 people in the Unites States had tested positive for WNV infection in 1999, in which this figure also included over 500 deaths. The virus is transmitted via the bite of an infected mosquito. Infected people may have shown mild, flu-like or no symptoms. Elderly people and those with lower immunity have higher risk of this disease. Significant symptoms generally appear within 2 to 14 days after the bite of an infected mosquito.

Avian Flu

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Avian flu (influenza) is influenza A virus which normally hits birds, and the virus rarely causes infection in humans. However, confirmed cases of human Avian flu infection had been reported since 1997.

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Human became deadly sick after having a direct contact with sick birds, ducks, turkeys, or chickens which are infected with H5N1 bird flu virus. Infected persons will have flu-like symptoms, which include coughing, fever, sore throat and muscle aches. The scary thing about this avian flu is that it can rapidly progress to acute lung problems, serious respiratory distress syndrome and pneumonia. The death of the infected people will only take a short length of time (9 to 10 days) from the start of the symptoms.

Polio

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Between 1930 and 1960, acute Polio (infantile paralysis or poliomyelitis) was reported to cause about 2,000 deaths, with its large epidemic outbreaks occurred in the late 1930s and early 1940s. From 1930 onwards, there’s been approximately 40,000 people reported being infected with paralytic polio in Australia. Its outbreak is particularly significant in areas with poor hygiene.

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Polio is a viral disease that is caused by enteroviruses, in which they’re observed to survive for a longer time outside of the intestinal environment. As compared to other viruses, the polio viruses are the most difficult viruses to be removed from the skin; even you wash your skin with soup and water. People get infected with polio viruses via the fecal-oral route, either via indirect or direct contact and it’s highly contagious during its acute stages as well as during the incubation periods. The disease may have mild or non-specific symptoms, with the common symptoms like back and neck stiffness, photophobia (sensitivity to light), headache, breathing, swallowing and/ or speech difficulties, and paralysis.

Now, you can gain more health knowledge by visiting my health blog entitled HealthAssist. More upcoming updates and latest health information are right on the way!