Archive for World Health Organization

Ask a Scientist : “So What’s a Parasite Anyway?” Lecture Jim McKerrow Cont.

Posted in Science with tags , , , , , , , , , , , on April 20, 2013 by neandergal
Ascaris


Ascaris

Parasites, parasites of the intestinal walls! Which is the most gross of them all? The most gross parasite title has to go to the most common of helminths, Ascaris lumbricoides.

According to the World Health Organization, Ascaris Lumbricoides infects approximately 30% of the world’s population. Infections for the most part, are in the rural areas of developing countries that use untreated human waste for fertilizer and irrigation. Without access to clean water and expensive fertilizer, farmers are left with little else to use, but human waste to grow their produce. A 2008 report in National Graphic news on the use of Human Waste cites that 200 million farmers world wide use human waste for fertilizer. The eggs from human feces used as fertilizer end up in the soil where they can stay fertilized for up to 10 years.

The eggs find their way into the human food chain via contaminated unwashed hands during food preparation, unwashed fruit and, or undercooked vegetables or fruit. When fertilized eggs are ingested, the eggs hatch in the upper intestinal tract where the larvae then penetrate the wall and move into the portal and systemic circulatory system. Once in the circulatory system, the larvae enter the lungs. In the lungs, the larvae penetrate aveoli walls and make their way up the bronchial tree to the throat. The larvae is swallowed by the host and ingested. In the lower intestines, the larvae attaches to the mucosa of the wall and feeds off the host’s partly digested food and grows to an adult. Adult Ascaris lays up to 200,000 eggs per day. The eggs are then excreted in feces. The infected feces returns to the land as fertilizer and the life-cycle of A lumbricoides repeats.

The Ascaris worm grows to approximately 30cm and about 2-4mm in diameter. The females are a little thicker and longer with their vulva making up a third of the length of the body. Gulp!

Sources:
Introduction to Microbiology, 9th Edition, Tortora, Gerard.J, Funke, Berdall R., Christine L. Case. Publisher: Pearson Benjamin Cummings. 2007 print.
Center for Disease Control – Ascariasis page
National Geographic 2008 report on use of human waste as fertilizer.
Ask a Scientist website
Dr. J. McKerrow UCSF page.

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Foreskins are not Clitorises

Posted in Religion, Science with tags , , , , , , , on June 1, 2010 by neandergal

“I was genitally mutilated at the age of ten. When the operation began, I put up a big fight. The pain was terrible and unbearable… I was badly cut and lost blood… I was genitally mutilated with a blunt penknife. After the operation, no one was allowed to aid me to walk… Sometimes I had to force myself not to urinate for fear of the terrible pain. I was not given any anesthetic in the operation to reduce my pain, nor any antibiotics to fight against infection. Afterwards, I hemorrhaged and became anemic. This was attributed to witchcraft. I suffered for a long time from acute vaginal infections.” -Hannah Koroma, Sierra Leone (Amnesty International Website)

        Recently, the American Academy of Pediatrics suggested the nicking (cutting) of the clitoris as a compromise to help prevent more serious grades of female genital mutilation. The suggestion was met with outrage and the AAP subsequently withdrew their statement. Female genital mutilation (FGM) is the ritual practiced by some Muslim communities that often entails complete removal of the clitoris and labia and stitching up of the raw wound allowing a small hole for menstrual flow and urination. According to the World Health Organization (WHO) surveys, prevalence of the practice varies widely. The prevalence is 85% in seven of the 28 countries identified by the WHO. As usual, whenever the subject of female genital mutilation comes up, the anti-male-circumcision brigade rear their ugly heads (pun intended) and claim, “it’s all mutilation!” Those who draw parallels between male circumcision (MC) and FGM tend to fall into two groups; the moral relativists who contend that both FGM and medical circumcision is genital mutilation and the anti-circumcision deniers who deny any evidence that medical neonatal male circumcision has health benefits. Those against medical male circumcision claim the procedure is barbaric, forced upon children and is mutilation of the genitalia. One would never think it necessary to state an obvious fact that foreskins are not clitorises, but alas, there is a proliferation of misinformation and view points that suggest a warrant for a full explanation. There are no parallels to be drawn between medical male circumcision and female genital mutilation.

        It is impossible to argue with moral relativists who claim that referring to FGM as “dehumanizing” is a valued judgement. We cannot pass judgement because there are no universal rights or wrongs. This is the usual wishy-washy mantra of the moral relativist. Fortunately, we do pass valued judgements which is why the WHO published in 2008, Eliminating Female Genital Mutilation: an interagency statement. The practice of FGM violates numerous international human rights treaties listed in the statement. FGM is dehumanizing, because it violates the rights of a child. According to the WHO statement, “One of the guiding principles of the Convention on the Rights of the Child is the primary consideration of ‘the best interests of the child’.” FGM hardly serves a child’s best interests, which is protection from harm that inevitably has dire and irreversible physical and mental health consequences. FGM interferes with a woman’s body in a way that causes extreme pain, denial of sexual pleasure, serious health risks some of which include, recurring urinary tract infections and child birth complications that endanger a mother and her baby’s life (this is assuming she reaches child bearing age.) Another problem arises when the moral relativists refer to male circumcision as “mutilation.”

        Male circumcision as part of a non-religious medical procedure is not mutilation. Removal of the foreskin does not interfere with a man’s physical or mental health. The clitoris is analogous to the glans penis or head; not the foreskin. When we start lobbing the heads off penises, then we will have the equivalent to FGM in the male. We do not lob heads off penises for solely religious practices. We do not lob heads off penises at all. We remove foreskins. Foreskins are not clitorises. Unlike FGM, there is strong evidence of health benefits to MC.

        According to the Center of Disease Control, male circumcision has numerous health benefits including lowered risk for penile cancer, and less risk of infection from STIs and growing evidence that circumcision may reduce the risk of HIV infection by 60% in heterosexual men. The evidence of health benefits is overwhelming. This has spurned an increased effort by the WHO and its agencies to increase male circumcision rates in countries (mainly African nations) where there is a high prevalence of and greater risk of disease. However, evidence is not required for the belief system of the deniers.

        Anti-circumcisers deny or refute the evidence of health benefits. They follow the same format as the anti-vaccination, anti-climate change, holocaust deniers, anti-evolutionists and so on by denying or refuting evidence that comes their way. Anti-evolutionists deny the fossil record, the anti-vaccination crowd claim “big pharma” conspiracies, holocaust deniers claim a Jewish conspiracy to set up the state of Israel and so on. Deniers generate their own facts from opinion and seek not truth, but misinformation that confirms their bias. In psychology this thought process is called, conformation bias. It is true that scientists can have the same problems with confirmation bias. Hence the need, for double blind studies and a peer-review process. Examining evidence would negate and therefore dismantle the deniers’ belief systems. Instead of accepting evidence that disproves their views, they systematically resort to straw man arguments or draw upon over-generalizations like equating medical MC with FGM which is false. Equating the two procedure is false because the evidence refutes any suggestion of equality between the two procedures.

        Medical male circumcision is a procedure with the intent to provide added health benefits in as painless and humane way as possible. It does not marginalize a male in anyway whatsoever. FGM is exclusively a religious ritual that has no health benefits. FGM continues solely because of its cultural significance in some Muslim communities. Amnesty International state that, “It is a human rights abuse that functions as an instrument for socializing girls into prescribed gender roles within the family and community.” Such an abuse does not in anyway compare to MC.

        The road to behavior and changes in attitude within these cultures is a long one. Political correctness in the form of moral and cultural relativism will delay progress and expose more young girls to abuse. It is quite rightly considered by the world as a form of child abuse. To draw parallels with any form of Female Genital Mutilation and Medical Male Circumcision is nothing short of being ignorant of the facts and misogynistic.