Are human beings privileged to be on planet Earth? Are we ready for the worst? Can we always find a new defense mechanism against new diseases?
We need to live in the reality of each day:
If we feel privileged to be on “Planet Earth”, we need to review a little the statistics. The probability in having us alive on this planet is in the millions, billions or even trillions. There is a need to enjoy every second.
A minute contains 60 seconds while 60 minutes bring an hour. There are 24 hours in a day, 365 days in a year and if we rely on the lifetime expectancy of the human being reaching 74, then we will expect to be able to live at least two and a quarter trillions of seconds.
On a medical point of view, we have learned of the existence of 78 organs in the body with 12 major organ systems. Each human body is composed of about 15 trillion of cells reproducing self each 7 year and being vulnerable to 30000 known diseases. Only 1/3 of these diseases can find treatment.
We know of the existence of 320000 viruses which have caused infectious diseases. Some are very well known like the one responsible of common cold, HIV/AIDS, Influenza, Measles, Rubella, Measles, Chicken Pox, Mumps, Polio, Mononucleosis, Ebola, West Nile Fever, Chickenpox, Hepatitis, Meningitis, Encephalitis, Pneumonia, SARS etc.
It is not always easy to destroy those viruses without damaging or destroying the healthy living cells of a human body.
The same is encountered when a bacterium is found in our body. There are an estimated 750 species of bacteria living in the human gut only and ten times more in the remaining human body enjoying a “peaceful symbiosis”, relatively harmless. Those bacteria can become out of control generating diseases, weakening the immune system or attacking other parts of the body where they are not welcome.
Bacteria have the richest evolutionary history on earth and have been found in fossils old of 4.5 billion years. They have learned how to adapt and survive to new situations, and it becomes at time so difficult to get rid of them, once the body is under a bacterial attack.
Once a person gets ill from a viral or a bacterial infection, those pathogens try to reproduce at our expense. Some will wait passively prior to be ingested and once ingested, they will start replicating furiously. In the respiratory system, they will force the host to sneeze or cough into the atmosphere projecting their progeny. This is the way, Influenza, the common cold or even the whooping cold are transmitted to others.
Other pathogens prefer the digestive system: The cholera bacteria, once ingested, duplicates so rapidly, in a such way that the bowels of a patient suffering from this infestation, will produce near 3 gallons of rice water in less than 24 hours and imposing a massive dehydration and surely death if untreated.
Other microbes will modify their hosts: Genital warts, Syphilis, Smallpox cause sores to break out the skin and to propagate after direct contact.
The virus of Rabies is so invasive that it will cause inflammation of the brain in human and other mammals with intense confusion, fear of water and surely death in the next 3 months after being bitten by a rabid animal (dogs, foxes, bats etc.). In humans the disease can be transmitted through any mucosal contact, and typically, the salivary glands will get infected and the patient will develop profuse foaming, with aquaphobia and soon will die.
Parasites and blood born micro-organisms such as in Typhus, Malaria, Yellow Fever invade the lymphatic system or the blood stream to attack the body’s natural defenses and lead to multiple organs failure.
Malaria is carried by the mosquito Aedes Genus “Anopheles” and the infectious plasmodium may hide into the host kidney, remaining asymptomatic for a while and suddenly, rebounding into the bloodstream.
The bubonic plague comes from a dormant bacterium found in the dry feces of rodents. The spores can be inhaled, moving to the lymphatic system leading to buboes which engorge until they burst out into the lungs. The bacteria can also penetrate the lung’s wall and infiltrate the lungs allowing the bacteria to be transmitted through coughing and sneezing with a 98% mortality rate in a matter of hours.
Recently, in 2014, an epidemy of Ebola placed the world on alert. A resurgence of a deadly virus known to be found in humans and primates, pigs and fruit bats, can be transmitted through the direct contact of an animal or a human, dead or alive, caring the disease. Semen, blood, flesh or mucus can carry the Ebola virus.
Newer viruses are invading the world in which we are living in. The Zika, virus, unknown to most people, is spreading explosively, worldwide. The surprise in this problem it is a familiar mosquito-vector, Aedes Genus, Anopheles, well known to us, which is now caring this new disease, alarming the population.
In fact, women from Senegal to Cambodia and Brazil to the Caribbean in passing by the French Polynesia, who contacted the disease while pregnant, started delivering babies with congenital malformations of the brain like microsomia, neurologic disorders like Guillain-Barre syndrome with auto-immune deficiency. This virus was given the name of its place of discovery, deep in Uganda, Africa, in the forest of Zika. The disease has affected the same monkeys on which studies were performed to eradicate Yellow fever in 1947 and now found to be transmitted by the same mosquito. Amniotic fluids of at least 2 mothers who delivered, were found to be positive for the Zika virus.
The world remains anxious because even if the WHO (World Health Organization) and the CDC Center for Disease Control and Prevention) consider those diseases as public health emergencies, it will take time to convince others on the importance for a coordinate effort to face the menace of propagation in the world.
We are evolving around Bacteria, Viruses, Microbes, Parasites, Funguses etc. and we need to understand as human being that those fine microscopic machines have resisted and adapted to the test of Time, coming out stronger and stronger from each battle. We will need a more efficacious international response prior to declare victory over any new “mutation” of these same micro-organisms.
Maxime Coles MD
References and Sources:
Centers for Disease Control and Prevention (CDC)
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
Division of High-Consequence Pathogens and Pathology (DHCPP)
Viral Special Pathogens Branch (VSPB)