4 Treatment and Prevention

Reading 2

An Ounce of Prevention is Worth a Pound of Treatment

In this reading students explore treatments and measures for preventing infectious diseases. Students should understand that while antibiotics can be effective for eliminating bacterial infections, no such treatments are available at present for viral diseases. At best, drugs can alleviate the symptoms, which may help the body’s immune system function more effectively to clear the infection. Students consider measures that can prevent disease and why prevention is more cost effective than treating a disease. Students are introduced to vaccines as a major preventative measure against infectious diseases.

Attributed to Benjamin Franklin, this quote actually reads “an ounce of prevention is worth a pound of cure.” Whether treating or curing, it is far more costly to treat a disease than to prevent it. Being sick can be financially draining due to expensive medicines and lost work time. Being sick can also be physically, psychologically and emotionally draining (recall the last time you had the flu or a stomach bug) and may result in long term physical disabilities or even death.

Treating the Disease

Morbidity (sickness) and mortality (death) caused by bacterial infections demonstrated a significant decline since the discovery of antibiotics. Antibiotics are chemical compounds that kill bacteria or inhibit their growth. Antibiotics are produced in nature by soil bacteria and fungi as a means of killing other microbes that compete for food, water, and other resources. In recent years many pathogenic (disease-causing) bacteria have become resistant to the most common antibiotics, but these drugs still remain the most effective treatment for bacterial infections.

Antibiotics are totally ineffective against virus. Although intensive research is underway to develop drugs that can treat and cure viral diseases, to date no effective antiviral drugs exist. Viruses replicate inside cells, using the host’s machinery to make its proteins and reproduce. Because they are “hidden” away within a cell, developing a drug to treat and cure viral diseases is difficult.

In the case of RNA viruses such as influenza, measles, and polio, the high rate of mutation makes drug design challenging because the proteins that serve as targets for a drug are constantly changing. At best, treatment primarily involves alleviating the symptoms of the disease and limiting but not eliminating the virus. These treatments range from bedrest and chicken soup to complex drug regimens for AIDS. Treatments that address the symptoms of the disease not only make you feel better, but can allow the immune system to function more effectively. You will learn about the role of the immune system in protecting against viral infections later in this module.

Preventing the Disease

Prevention of infectious diseases occurs at three levels: public health measures, personal hygiene, and vaccination programs.

Improvement in public water supplies and sanitation systems of cities and towns have led to declines in infectious diseases worldwide. Ensuring clean water for drinking and cooking, and having effective systems in place for waste disposal have reduced the incidences of water borne diseases such as cholera, amebiasis (caused by a parasitic amoeba), and other gastroenteritic (diarrhea-producing) diseases significantly.

Regulations monitoring food processing and preparation have protected consumers against food poisoning caused by Salmonella, E. coli, and norovirus, and infections by food borne parasites such as tapeworms. Animal and pest control have also contributed to the reduction of infectious diseases. Rabies vaccinations are required for dogs. Malaria was eliminated from the southern United States through government sponsored mosquito-control programs.

Epidemics of bubonic plague have been prevented through good hygiene, clean water, and effective rodent control. In some cases, such as the SARS epidemic (see Module 3 – Viruses Go “Viral”), quarantining infected individuals can protect the at-risk population

Hygiene

Personal hygiene plays a critical role in protecting each individual from infection. Everyday activities such as frequent hand washing, careful food preparation, thorough cleaning of kitchen areas and bathrooms, safe sex, and not sharing toothbrushes, drinking glasses, and eating utensils can provide simple but effective protection. Good eating habits can also bolster your immune system, your own personal defense system against infectious diseases. (You will learn more about the immune system in Reading 3 – On Guard). Staying at home when you are sick may not protect you (although it can speed your recovery) but will prevent the spread of whatever ails you to others as will covering your mouth when you cough or sneeze. Educating at-risk populations about how a disease is spread can go a long way in preventing the spread of infectious diseases. For example, once families understood the danger of direct contact with symptomatic Ebola patients, caretakers and family members altered their caretaking and burial practices to avoid contracting the disease.

Vaccines

Next to improvements in public water and sanitation systems, vaccines have had the most significant impact on reducing morbidity and mortality of infectious diseases, particularly in children. The World Health Organization estimates that vaccines for measles, bacterial meningitis, tetanus, diphtheria, polio, pertussis, and rotavirus have saved the lives of an estimated 7.5 million children over the last 10 years.

Problems to Solve

Despite all these advancements infectious diseases still kill over 17 million people a year; that’s nearly 50,000 men, women and children dying every day. Many low-income countries and countries torn by political unrest do not have effective infrastructures in place that provide clean water, adequate waste-disposal systems, and effective vector (mosquito, black fly, and other insects) control. Vaccination programs require coordinated programs that ensure consistent access to children and properly maintained supplies of vaccines and medical equipment, and trained healthcare workers.

Additional Resources for Module 4 Reading 2

New drug could cure nearly any viral infection, Medical Xpress

This article describes a drug being developed at the Massachusetts Institute of Technology that works by targeting a type of RNA produced only in cells that have been infected by viruses. The drug would identify cells that have been infected by any type of virus, and then kill those cells to terminate the infection. In theory it could be effective against a broad range of viruses since it targets the infected cell rather than the virus itself.

Ebola virus: Why isn’t there a cure?, livescience.com

This article discusses why it is difficult to develop a treatment for Ebola.

The Story of Ebola, IFRC

This moving animation describes how one village in Africa stopped the spread of Ebola by changing personal activities.