Contemporary Global Issue: Greenhouse Gases

Greenhouse gases are gases that capture heat in the atmosphere and they include water vapor, carbon dioxide, methane, nitrous oxide, fluorinated gases, and ozone. Each of them can stay in the atmosphere from a few years to thousands of years. In the atmosphere, these gases combine and cause significant effects on human health around the world.

Human activities change and accelerate the effects of greenhouse gases through

•   Burning of natural gas, coal and oil, including gasoline for automobile engines, increases the level of carbon dioxide in the atmosphere.

•   Certain farming practices and changes in land operation increase the levels of methane and nitrous oxide.

•   Industrial gases that do not occur naturally significantly contribute to the greenhouse effect.

•   Deforestation leaves fewer trees to perform significant function.

•   Population growth due to increase people’s use of fossil fuels for heat, transportation, and manufacturing, all of which increase the level of greenhouse gases continues to increase. Increased farming to feed millions of people around the world result in emission of more greenhouse gases to the atmosphere.

                                             Global Greenhouse Gas Statistics

In 2012, the study indicated that the burning of fossil fuels and increased deforestation of native forests has resulted in a 40% increase in the atmospheric concentration of carbon dioxide.

Global Greenhouse Gas Emissions

                                            Global Greenhouse Gas Emissions by Source

Greenhouse Effects on Human Health

People with asthma and other lung problems are at risk from increasing ground-level ozone due to particulate air pollution that resulted from increase carbon dioxide. Also significantly affected by greenhouse gases are elderly persons who present with heart and lung problems, young children, and homeless people. At greatest immediate risk, the computer modeling study contended, are cities that are already experiencing a high degree of air pollution.

Greenhouse Gas Prevention Alternatives

§  Resort to using renewable energy.

§  Go green with technologies, including power plants and transportation.

§  Continue searching new options for electricity production.

§  Planting more trees.

References:

http://www.epa.gov/climatechange/ghgemissions/global.html

http://www.acs.org/content/acs/en/climatescience/greenhousegases.html

https://search.yahoo.com/search

http://environment.about.com/od/globalwarming/a/greenhouse.htm

http://en.wikipedia.org/wiki/Greenhouse_effect#mediaviewer/File:The_green_house_effect.svg

Virus: Human Immunodeficiency Virus (HIV)

HIV remains a persistent potential global problem, despite progression made throughout the years in preventing and treating HIV infections.

Identify statistics about its prevalence around the world

HIV disease continues to be a serious health concern throughout the world. Studies indicate there were approximately 2.3 million new cases of HIV in 2012 worldwide. The studies also show that about 35.3 million people around the world are living with HIV. In 2012, over 9.7 million people living with HIV in low and middle-income countries had access to antiretroviral therapy (ART). The studies also indicated that over 1.6 million people died from AIDS-related illnesses in 2012. Additionally, approximately 36 million people with AIDS have died around the world since the beginning of epidemic. Sub-Saharan Africa disproportionately experiences the burden of HIV/AIDS, with nearly 1 in 20 adults living with HIV. HIV/AIDS significantly affects other parts of the world, including Latin America, Caribbean, Eastern Europe, Central Asia, and South and Southeast Asia.

United States: About 50,000 people get infected with HIV annually.  In 2010, approximately 47,500 new HIV infections were reported in the United States. At the end of 2010, an estimated 1.1 million people in the United States were living with HIV. Of those people infected with HIV, approximately 16% of them do not know their status of HIV infection.

                                                 

                                                    Modes of the HIV Transmission

For HIV infection to occur, infected blood and semen or vaginal secretions must enter one’s body. A person cannot be infected with HIV through normal contact, including hugging, kissing, dancing or shaking hands with someone with HIV/AIDS. HIV cannot be transmitted through the air, water, and insect bites.

A person can become infected with HIV in many ways, including: sexual intercourse, blood transfusions, sharing needles, and during pregnancy or delivery or through breast-feeding.

Treatment Options

The classes of anti-HIV drugs include:

§  Non-nucleoside reverse transcriptase inhibitors (NNRTIs): These drugs disable a protein HIV requires to replicate or make copies of itself.

o Examples: favirenz (Sustiva), etravirine (Intelence) and nevirapine (Viramune).

§  Nucleoside reverse transcriptase inhibitors (NRTIs): These drugs are faulty versions of building blocks that HIV needs to make copies of itself.

o Examples: Abacavir (Ziagen), and the combination drugs emtricitabine and tenofovir (Truvada), and lamivudine and zidovudine (Combivir).

§  Protease inhibitors (PIs):  These drugs disable protease, another protein that HIV needs to make copies of itself.

o Examples: Atazanavir (Reyataz), darunavir (Prezista), fosamprenavir (Lexiva) and ritonavir (Norvir).

§  Entry or fusion inhibitors: These drugs block HIV's entry into CD4 cells.

o Examples: Enfuvirtide (Fuzeon) and maraviroc (Selzentry).

§  Integrase inhibitors: Raltegravir (Isentress) works by disabling integrase, a protein that HIV uses to insert its genetic material into CD4 cells.

HIV Prevention Methods

§ Use a new condom every time you have sex.

§ Consider the drug Truvada. In 2012, the US Food and Drug Administration approved the use of the combination drug emtricitabine-tenofovir (Truvada) to decrease the risk of sexually transmitted HIV infection in those who are at high risk. Truvada is also used as an HIV treatment along with other medications.

§ Tell your sexual partners if you have HIV.

§ Use a clean needle.

§ Get medical care right away if you are pregnant.

§ Consider male circumcision. There is evidence that male circumcision can help minimize a man’s risk of acquiring HIV.

References:

http://www.mayoclinic.org/diseases-conditions/hiv-aids/basics/causes/con-20013732

http://healthfavo.com/hiv-virus-life-cycle.html

http://www.cdc.gov/hiv/basics/statistics.html

https://images.search.yahoo.com/images/view

Parasite: Cryptosporidium

Cryptosporidium is a microscopic parasite that causes the diarrheal disease cryptosporidiosis. The parasite and the disease are known as "Crypto." There are several species of Cryptosporidium that infect both humans and animals. The Cryptosporidium has an outer shell that protects and allows the parasite to survive outside the body for long durations. The outer shell makes the parasite tolerant to chlorine disinfection.

The parasite can be transmitted in many ways. The most common modes of transmission include drinking water and recreational water in every region of the United States and throughout the world. The parasite typically comes from run off water from cattle farms.

Identify statistics about its prevalence around the world

United States: In  2009, 7656 confirmed and probable cases of cryptosporidiosis (2.5 per 100,000 population) were reported. In 2010, 8951 confirmed and probable cases (2.9 per 100,000 population) were reported. Cases were reported in children aged 1–9 years and adults aged 25–29 years.

Cryptosporidium Life Cycle

Cryptosporidium Treatment Options

§ Anti-parasitic drugs: E.g., nitazonide (Alinia) to reduce diarrhea by compromising metabolic processes of cryptosporidium organisms, azithromycin (Zithromax) in combination with one of these drugs for people with compromised immune system.

§ Anti-motility agents: E.g., loperamide and its derivatives (Imodium A-D) slow down movements of intestine and increase fluid absorption to alleviate diarrhea and restore normal stools.

§ Fluid replacement: Oral or intravenous replacement fluids and electrolytes, including sodium, potassium, and calcium, all maintain body fluid balance by keeping body hydrated.

§ Antiretroviral therapies: For those with HIV/AIDS, increasing active antiretroviral therapy (HAART) can decrease viral load in the body and boost immune response. Restoration of immune system to a certain level may resolve symptoms of cryptosporidiosis.

Cryptosporidium Means of Prevention

§ Practice good hygiene, including washing hands with soap and water after using the toilet and changing diapers, and before and after eating.

§ Thoroughly wash fruits and vegetables with uncontaminated water. Avoid eating foods suspected of contamination. Avoid uncooked foods when traveling in developing countries.

§ Purify drinking water if traveling in an area with a high risk of infection or having a weakened immune system.

§ Limit swimming activities in lakes, streams and public swimming pools, particularly if water is likely to be contaminated or if one has a compromised immune system.

§ Avoid fecal exposure during sexual activity.

§ Carefully handle newborn farm and domestic animals. Wash hands after handling these animals.

References:

http://www.cdc.gov/parasites/crypto/

http://www.mayoclinic.org/diseases-conditions/cryptosporidium/basics/definition/CON-20030375

http://www.cdc.gov/healthywater/swimming/rwi/illnesses/cryptosporidium.html

http://www.cdc.gov/parasites/crypto/biology.html

http://www.cdc.gov/mmwr/preview/mmwrhtml/ss6105a1.htm

https://images.search.yahoo.com/images/view