Book Review: Parasite Rex

I've been juggling a few books recently, so for my March-April-May book, I read Parasite Rex by Carl Zimmer. I borrowed this book from a co-worker who has a phD in biology. One day, we started talking about cats, and he mentioned toxoplasma gondii. He told me this tale about a parasite that gets on rats, makes the rat hang around cats, and the parasite gets onto the cat. This parasite is also found on humans who own cats, and it has connections with neurological disorders (schizophrenia) and other psychological effects. This tale was true, and I was intrigued, so he lent me this book.

I absolutely loved this book! I kept stopping to tell my boyfriend about parasites. I had my opinions about parasites change as I read the book.

When I started reading Parasite Rex, I realized how dangerous parasites can be. Zimmer explains how a simple parasite can cause sleeping sickness or river blindness, as he has seen in Africa. I even avoided pork for a short time while I was reading about tapeworms. I started looking at things in every day life, wondering, "How many parasites are on that?" I was a little sickened by the thought of no escape from parasites (delusional parasitosis).

I learned how advanced parasites really are (in my head, I had imagined stupid little worms with no clear goal in life). Zimmer explains the life cycle of some parasites, how they transform their shapes to something completely different, just to help it get to the next point in its life cycle (or move from one part of a body to another or arrive at its final host). Parasites fascinated me with their endurance. They could live on a toad for months (underground), wait for it to emerge, break free at the mating pond, and find a new host, all within a short window of time. Some parasites can live in the human body for 10+ years! While some parasites are ruthless, such as the parasitic wasps that inject their spawn into caterpillars (and basically give the host a slow, painful death), others are gentler. There is a parasite that can infect crabs, making them infertile, and take over the crab to live otherwise normally, just so it has a host to feed upon.

Zimmer discusses various diseases and sicknesses, and why some traits and disorders are useful to protect a being from parasites (sickle cell anemia and its resilience against malaria). He also points out how some parasites make their host look more attractive, so it can continue its life cycle or infect other hosts. Smart little buggers they are.

Near the end of the book, I saw how much we can learn from parasites, and how they are necessary to the world! Zimmer explains that Crohn's diseas and colitis may have come about with the eradication of intestinal worms in wealthy families (in fact, a study has been done showing remission with the addition of parasites to humans...parasite proteins in the future?).

Parasites have been used for biological control, helping save the African cassava crops from destruction. However, Zimmer makes it clear that bringing a parasite into a system must be carefully calculated and studied. Right now, there is the green crab on the west coast, eating all the cockles (a massive amount each day). It would be nice to get rid of these guys, but whatever we do, we must take into account how it will affect the rest of the ecosystem (we don't want to kill the other crabs too).

I love science, and I would be thrilled to read another book about parasites. I definitely recommend this book. I learned a lot, and the book was easy to read and understand.