Global Health Threats Articles

Cheat Sheet / Updated 03-27-2016

Whenever something big hits the news, you can be sure that both facts and misinformation will be floating around. The Ebola outbreak of 2014 is no different, and it has everyone’s tongues wagging. The problem is that not all of the information that you hear is true, which just adds to the feelings of panic and concern you might already feel. Someone once said that people fear what they don’t know, and that knowledge is power. This is a quick and handy guide to some of the most important facts and information about Ebola.

Article / Updated 03-26-2016

Ebola virus disease (or Ebola hemorrhagic fever) was first found to infect humans in 1976. Because the deadly disease was discovered relatively recently, there is no cure or vaccine for Ebola, and treatment options are limited. Ebola is considered by the U.S. Centers for Disease Control (CDC) to be a highly infectious disease, yet not particularly contagious. The Ebola virus is infectious because exposure to a very small amount of it — perhaps as little as one virus particle — can cause a fatal infection. Ebola is not highly contagious because it spreads only by direct contact with secretions (blood, vomit, diarrhea) from a person or animal who has the disease. Read on for a timeline of the Ebola virus, from the first epidemic to 2014. (Note that the Democratic Republic of the Congo and the Republic of Congo are two separate countries.) 1976: The first recognition of the Ebola virus occurs in Zaire (now called the Democratic Republic of the Congo), resulting in 318 human cases and 280 deaths. Ebola got its name from the Ebola River, which was at the epicenter of the first epidemic. Almost simultaneously, an outbreak of a different strain of Ebola occurred in Sudan (now called South Sudan), resulting in 284 cases and 151 deaths. In Sudan, many of the infected were healthcare workers. In England, one person in a medical laboratory was infected after an accident with a contaminated needle; the patient survived. 1979: An outbreak of Ebola occurred in Sudan (now called South Sudan), resulting in 34 cases and 22 deaths. 1989: In a laboratory in Reston, VA (a suburb of Washington DC), macaque monkeys arrived from the Philippines for medical testing and were found to be infected with a new strain of Ebola (later named the Ebola-Reston virus*). No humans were infected, but the story led to the 1995 bestselling book, The Hot Zone, by Richard Preston. 1990: Ebola-Reston virus was discovered in laboratories in Virginia and Texas in monkeys imported from the Philippines. Four humans tested positive for Ebola antibodies but none got sick.* 1989-1990: Macaques died en mass at a primate facility that exports animals to the United States. Three workers in the facility tested positive for Ebola antibodies but none got sick.* 1992: Monkeys in a lab in Italy tested positive for Ebola-Reston virus. The monkeys came from the same Philippine export facility that was involved in the previous cases in the United States. No humans were infected. 1994: 52 people became sick and 31 died in gold mining camps in Gabon. The cause was originally thought to be yellow fever but was later identified as Ebola. A scientist contracted Ebola after conducting an autopsy on a chimpanzee in Ivory Coast. He was airlifted to Switzerland, where he recovered. 1995: An outbreak occurred in the Democratic Republic of the Congo (formerly Zaire), resulting in 315 cases and 250 deaths. The epidemic swept through hospitals and families. 1996: A small outbreak occurred in Gabon, resulting in 37 cases and 21 deaths, when a dead chimpanzee was discovered and eaten. 19 of the people involved in the butchering of the chimp became ill; the other cases were family members. A few months later, again in Gabon, another 60 cases resulted in 45 deaths. The source of the second wave of Ebola was also traced to the finding of a dead chimpanzee. A medical professional treating the Gabon cases became infected and was airlifted to South Africa. He recovered, but a nurse who treated him became ill and died. Infected monkeys were again discovered in Texas and the Philippines. 2000-2001: An Ebola outbreak in Uganda led to 425 cases and 224 deaths. This outbreak made it known that some African funeral practices can spread Ebola from the dead to the living. 2001-2002: An outbreak occurred at the border of Gabon and the Republic of Congo, which results in 122 cases and 96 deaths. 2002-2003: An outbreak occurred in the Republic of Congo, resulting in 143 cases and 128 deaths. Shortly after the epidemic in the same country, another 35 cases and 29 deaths were identified as from Ebola. 2004: An outbreak occurred in Sudan (now called South Sudan), resulting in 17 cases and 7 deaths. Sudan suffered an outbreak of measles simultaneously, which at first led to several cases of misidentification. 2007: An outbreak in the Democratic Republic of the Congo resulted in 264 cases and 187 deaths. An outbreak in Uganda resulted in 149 cases and 37 deaths and was identified as a new strain (the fourth) of the Ebola virus. 2008: The first known instances of pigs having Ebola-Reston are discovered at a farm in the Philippines. Six workers from the pig farm tested positive for Ebola, but none became ill.* An outbreak occurred in the Democratic Republic of the Congo, resulting in 32 cases and 15 deaths. 2011: One person in Uganda died of Ebola. 2012: Two outbreaks occurred in Uganda just months apart, resulting in 17 cases and 7 deaths. An outbreak occurred in the Democratic Republic of the Congo, resulting in 36 cases and 13 deaths. 2014: The largest outbreak of Ebola on record occurred in Guinea, Liberia, Sierra Leone, and Nigeria, resulting in 1528 cases and 844 deaths as of August, 2014. Two American doctors in Liberia contracted the virus and were airlifted to Atlanta, GA, where they recovered. An unrelated outbreak occurred in the Democratic Republic of the Congo, resulting in at least 2 deaths. Both of the 2014 epidemics are ongoing. *The Ebola-Reston virus has since been discovered to be the only one of the five strains of Ebola that is not contagious to humans.

Article / Updated 03-26-2016

Chagas is known as the kissing disease because the infection is usually transmitted from the bite of an insect called a Triatominae, also known as a kissing bug, which likes to feed on a warm blooded animal’s face while it is sleeping. (This includes more than 150 species of mammal — even humans — yikes!) Credit: ©iStockphoto.com/WebSubstance Chagas is actually caused by a sub-tropical protozoan parasite, Trypanosoma Cruzi (T. Cruzi.) This parasite enters the blood stream of its host and starts the duplication process, eventually infecting every cell of the host’s body with parasitic protozoa replicates. Often the host shows no signs of infection until between 10 and 30 years later when the chronic phase of the disease becomes apparent. Chagas disease was named after Dr. Carlos Chagas who discovered the blood parasite in 1909. The disease was not recognized or considered a health threat by the United States until the mid-1960s. Chagas disease is localized mainly in Mexico and Central and South America. The reports of infection outbreak in the United States and Europe are usually caught and treated in the early stages of development. Don't confuse Chagas with mononucleosis (mono), the "kissing disease" that plagues many high schools and is contracted by puckering up with your honey. The nature of the disease’s transmission can vary greatly. The method of Chagas transmission is listed here by percentage of people infected: 60% — Infected from bites from either an infected kissing bug or another infected mammal. 20% — Infected from parasite-contaminated blood transfusions or blood products. 13% — Infected from a mother to her unborn child (infection through the blood to the fetus.) 5% — Infected from eating food contaminated with the parasite, including breast milk. 1% — Infected from unprotected sex with an infected person in the chronic phase of Chagas (extremely rare.) 1% — Infected from parasite-infested organ transplants (parasite screening has been implemented in affected areas.) The symptoms of Chagas in humans The symptoms of Chagas change over time as the infection slowly spreads through the whole body. At the beginning of the infection (the acute phase), people usually show no signs or only mild symptoms of fever, sluggishness, headaches, swollen glands, loss of appetite, diarrhea, and redness/swelling at the site of entry to the body. For instance, if Chagas disease was contracted through a bite, the area around the bite will show signs of infection; if it was contracted orally through ingestion, then the signs of infections will be in the mouth and throat. After 2–3 months of being infected without treatment, someone with Chagas disease will enter the chronic phase. Some chronic symptoms include speech impairment, confusion, and loss of balance, which often occurs because of the severe brain swelling associated with Chagas disease. The risks of Chagas going untreated or undiagnosed People who enter the chronic phase of the disease without treatment will either become asymptomatic, never showing any signs of further symptoms, or they will develop devastating health issues decades after the initial symptoms occurred. These chronic health issues include severe inflammation in the esophagus, colon, lungs, glands, kidneys, brain, and heart. Other symptoms can occur as well, typically resulting in heart failure and eventually death! The chronic symptoms affect roughly only 30 percent of those who are infected with T. Cruzi. Essentially the disease can be compared to an allergic reaction, in which the parasitic protozoa that has infiltrated the infected person's body acts as the allergen. Treatment and recovery options available for those infected Since the symptoms of Chagas and the reproduction cycle is similar to that of HIV, the treatment is similar as well. Anti-parasitic drugs such as Benznidazole and DNA vaccine immunotherapies are most effective during the acute phase of the illness and lead to a cure in about 85 percent of those infected. During the chronic phase, however, immunotherapies and anti-parasitic drugs have shown to only slow the onset of the disease but not completely eradicate it from the infected person's body. Sadly, for many people that are already in the chronic stages of Chagas disease, there is no cure, and treatment involves managing all symptoms as they occur, such as organ transplantation surgery, stem cell therapy, and the use of immunosuppression drugs like Cyclosporin. The importance of preventing Chagas Since no vaccines have been developed to stop the spread of Chagas disease, roughly 8 million people worldwide are infected with the parasite, and about 13,000 deaths a year occur due to complications of the disease in its chronic state. Preventative measures have to be taken to ensure a lower risk of infection including decreasing the number of insects who carry the parasite as well as early blood screening tests for people who live or travel inside infected areas. If you are travelling in countries where the Triatominae (kissing bug) is known to live and bite, be sure to follow these steps to minimize your chances of contracting Chagas disease: Check with that country's local news outlets to see whether any current Chagas outbreaks are happening in the area you will be staying. Scope out the building/hotel room for any signs of Triatominae bugs. Look through your bedding thoroughly and use a mosquito net if available. Keep kitchens and bathrooms clean so no odors attract animals that the kissing bug likes to feed on. Be cautious of weird or unusual tasting food. Avoid sexual contact unless you are 100 percent sure your partner is not infected. Examine your body for bite marks daily. Have a simple blood test performed prior to returning home. Some promising vaccines are currently in development providing positive test results in other mammals infected with Chagas and are awaiting approval for human clinical trials.