Why in News
A huge clam that was on the verge of extinction has made a comeback, with a surge in numbers in waters off Croatia.
The clam, known as the noble pen shell or pinna nobilis, started dying out as a deadly pathogen spread in parts of the Mediterranean around 2016.
Numbers plummeted across the region and, until recently, scientists in Croatia only knew of around 10 surviving in their corner of the Adriatic.
Pinna nobilis
Pinna nobilis, also known as the noble pen shell, is a large bivalve mollusc that is native to the Mediterranean Sea.
It is the largest bivalve mollusc in the Mediterranean, growing up to 1.2 meters (4 feet) in length.
The fan mussel is a filter feeder, and plays an important role in the marine ecosystem by filtering water and removing impurities.
Pinna nobilis is a critically endangered species, and is on the verge of extinction.
The main threat to the species is a disease caused by the parasite Haplosporidium pinnae.
This parasite was first identified in 2016, and has since spread rapidly throughout the Mediterranean Sea.
The parasite causes the fan mussel to suffocate and die.
Other threats to Pinna nobilis include habitat loss and degradation, pollution, and overfishing.
Habitat loss is caused by activities such as coastal development, dredging, and anchoring.
Pollution can weaken the fan mussel's immune system, making it more susceptible to disease.
BCG Vaccine
The BCG vaccine is a vaccine that protects against tuberculosis (TB) disease.
It is one of the oldest and most widely used vaccines in the world.
It is estimated to have saved millions of lives. The
BCG vaccine is made from a weakened strain of Mycobacterium bovis, which is a bacterium that causes tuberculosis in cattle.
The vaccine is typically given to infants and young children.
The full form of BCG is Bacillus Calmette-Guérin.
The vaccine was invented by Albert Calmette & Camille Guerin, two French bacteriologists.
COMMENTS