Where are new pathogens coming from?

Question

Can anyone explain where new pathogens come from, and why old pathogens are re-emerging?

Answer 1

Pathogens are species of microorganisms, and species evolve over time. Because microorganisms reproduce in great numbers over a very short period of time, their evolution is faster than, for example, a human that only has a small number of offspring per generation. These evolutionary changes are from the "survival of the fittest" in which mutations that lead to better adaptations to the environment are favored, and those that are less successful are rejected.
Organsisms are constantly at war with pathogens. The line of defense is the immune system, but it is always being attacked by pathogens. For most of these attacks, the pathogen is unsuccessful because the immune system is very good at what it does. When it recognizes a pathogen that it has seen before and survived, it has antibodies that quickly retaliate. However, even common pathogens can be a threat when the immune system is compromised (for example, AIDS, immunosuppressing drugs). Another problem is the overuse of antibiotics. The antibiotics tend to kill off the weaker microbes, but may leave behind less susceptible microbes. These susceptibles are then resistant to the antibiotic.
Pathogens that are very aggressive (virulent) tend to be less favored, because they make their host too sick before they have a chance to be passed on. When these very virulent types of pathogens are able to reach the general population, those individuals that are particularly vulnerable (susceptible) to the pathogen tend to die, while the survivors with greater resistance (immunity) tend to live on, and ultimately reproduce.
This explanation only touches on some of the issues, but I think it's a really fascinating topic.

Answer 2

There is a balancing harmony in the nature among all the living organisms so that if one is changed for any reason by any form, it causes some other changes to some other organisms and natural systems. New pathogens emerge basically for 3 reasons:

1. When one balancing (known/ unknown) pathogen is suppressed or boosted by anyway, the roles of this pathogen on other pathogens and the system are changed that eventually, some dormant pathogens emerge out. For an example, many scientists believe that eradicating the small pox virus from the environment may play a role in molding some dormant viruses to be as HIV.

2. Man made viruses and pathogens may emerge as new ones while those are secretly tested among different sections of human. Some also believe that the HIV may be such a human engineered virus tested on the African people and apes.

2. Auto changes of the organisms as a natural evolutionary process that may select emerging and re-emerging a new pathogen to make some natural balance (Not necessarily we know those all).

Answer 3

Pathogens usually come from nature...They change their code so that they are not recognised...Old pathogens re-emerge because they can change their code therefore antibodies cannot recognise them so they cannot destroy them..I dont know if i completely understood ur question

Answer 4

They don't hurt at all. The time second time is nothing compared to the first time you get your lobes pierced. Lobes don't hurt. You should be fine.

Answer 5

People are rooting around in the jungle, eating monkeys and gorillas.

Answer 6

they really exist ,but was undetected by men.some arises due to mutation.when drugs are take imcompletely.