Influenza 101: This year’s flu and the next big concern

25th Sep 2015 Diseases, Viruses

It has been widely reported that this year’s flu vaccine is very ineffective. In fact, the CDC has now reported the vaccine effectiveness to be a dismal 18%. The reason for this is that the main virus that has been circulating, H3N2, is not included in this year’s vaccine. A universal vaccine is currently in clinical trials, but its effectiveness and release are currently unknown.

In review, there are three types of influenza or “flu” that affect humans (Type A, B, C). As we all know, the flu can cause symptoms that range from mild to severe including fever, sore throat, muscle pains, coughing, headaches, nausea, vomiting and lethargy. Type A influenza has been known to be associated with the worst outbreaks and cause the most severe disease. Wild birds are the natural host for this type of flu. While similar to the influenza virus, the avian form of influenza is from a different subspecies. All influenza that has occurred in birds is from the Type A subspecies. The avian flu has historically been lethal and has caused many deaths worldwide.

The ‘H’ in H3N2 refers to hemagglutin which is a glycoprotein that binds the virus to the host cell. ‘N’ refers to neuraminidase which is an enzyme found on the surface of the influenza virus that enables the virus to be released from the host cell. The numbers that accompany H and N refer to subtypes of the virus.

There have been several strains that have been associated with pandemics. H1N1, H2N2 and H3N2 subtypes were avian based. Newer subtypes of H1N1 include the swine flu.

In 2013, the emergence of H7N9 in China has raised concern for another worldwide pandemic. H7N9 is an avian based subtype but it has been reported that transmission from person to person may have occurred. There is a much larger mortality rate associated with H7N9 than with other subtypes. In fact, nearly one third of those infected during a 2013 outbreak died from complications associated with the disease. Some infectious disease specialists and researchers have laid claim that N7N9 could cause a worldwide pandemic, similar to the last one seen in 1918 which caused over 100 million deaths.

The first case of H7N9 in North America was reported earlier this year. A Canadian citizen tested positive for the disease upon returning home from Hong Kong in late January.

The underlying source for H7N9 appears to be from infected chickens that has spread rapidly among several provinces in China. There has been very limited reports of human to human transmission. The World Health Organization (WHO) is calling H7N9 one of the most lethal viruses seen. A vaccine is currently in clinical trials.


Measles in Florida

03rd Mar 2015 Medical News, Viruses

One of the major health headlines in 2015 has been a measles outbreak. The current outbreak is believed to have begun in Disneyland and Disney California Adventure Park in late December 2014. Since that time, well over 115 cases of measles have been reported in multiple states. In Florida, 4 cases have been reported at the time of this writing. Based on information from the Florida Department of Health (DOH), the four individuals identified, traveled to Florida, including Tampa and are not state residents. Two of the individuals are U.S. citizens while two are international visitors. None of the four were vaccinated against the disease. The DOH and local health departments has been aggressive about monitoring individuals who were potentially exposed to the four travelers.

This recent identification of measles in the Sunshine state comes after a prior outbreak in the Orlando area. Case information from the Center for Disease Control and Prevention (CDC) identified a 10 year unvaccinated resident of Orange County as the index case last year. Subsequently, her 3 siblings all contracted measles within a week of the diagnosis. The parents of the children claimed religious exception to vaccination. Nasal specimens that were collected from all of the children by the Florida Department of Health and Bureau of Public Health Laboratories, did test positive for the measles virus RNA. An additional case of confirmed measles was identified by the DOH in Miami-Dade County. This case was identified nearly one month after the Orlando cases. A Brazilian citizen, without evidence of vaccination, reported having visited a theme park in the Orlando area. Genomic sequencing of the Brazilian patient was identical to the cases reported in Orange County. It is believed that this exposure likely came from the same Orlando based theme park where the index patient’s family had visited one month prior.

Measles is a highly contagious disease with an estimated incidence of more than 20 million cases worldwide. Complications occur in about 30% of cases in which over 164,000 deaths occur worldwide yearly. Cases in the U.S. tend to be sporadic and commonly occur from unvaccinated international visitors and from U.S. citizens traveling abroad.

The MMR vaccine has been shown to be highly effective at preventing the spread of measles, however, its use is under scrutiny by subsets of the population that contest that vaccines are harmful and can cause autism. Florida State Surgeon General and State Secretary of Health, Dr. John Armstrong has reported that approximately 93% of kindergartners in Florida have received vaccination for measles, mumps, and rubella (MMR vaccine).


The Lone Star Tick in Florida

24th Feb 2015 Medical News, Viruses

Amblyomma Americanum, also known as the Lone Star tick, has been identified throughout the southeastern U.S. including central Florida.   In fact, this is the most common human biting tick in Florida (Clark KL, Leydet B, Hartman S.  International Journal of Medical Sciences 2013). The ticks are commonly found in wooded and animal resting areas.

The Heartland Virus, also known as Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV), was first discovered in the U.S., in northwestern Missouri, in June 2009.  The virus results from a tick-borne illness from the Phlebovirus genus.   The U.S. Center for Disease Control and Prevention (CDC) has traced the virus to the Lone Star Tick. Current investigations are looking at whether the virus can be transmitted by other vectors including mosquitos and flies.

Most of the cases of the Heartland virus identified so far occurred between 2012 and 2014 and have included two deaths.  All patients who became ill had been bitten by a ticks within the previous 14 days between May and September. Reported symptoms included fever in excess of 100.4 F, headaches, lethargy, and diarrhea, loss of appetite, nausea, and joint pains.  Additionally, low white blood cell counts and low platelets (thrombocytopenia) also were seen in these cases. The diagnosis was made after exclusion of other causes of infectious disease and also through antibody titers.

At present, there is no specific treatment for the Heartland virus. Antibiotics are not effect against the virus. Supportive care to include IV fluids and analgesics are recommended.   Recommendations for prevention includes the use of appropriate clothing such as long sleeve shirts and pants. The use of insect repellents including ones that contain DEET are recommended, however, this is not always effective.

Interestingly, it has been reported that a bite from a Lone Star tick can trigger an immune system response leading to a meat allergy. Dr. Scott Commins and Dr. Thomas Platts-Mills from the University of Virginia, identified the Lone Star tick as the culprit to causing this unusual allergy in 2011 (Current Allergy and Asthma Reports  Feb 2013 13(1): 72-77).  The number of cases have continued to be seen with increasing frequency.  As many of the reactions are often delayed, making the correct diagnosis has been challenging. It is unknown why only some develop the meat allergy.

Some have experienced long term symptoms associated with the Heartland virus from Lone Star tick bites.  It is unknown if the development of a meat allergy from this same tick species is a permanent one.

Craiglist and HIV: Back to Basics

12th Feb 2015 Diseases, Medical News, Viruses

With the recent study released by the University of Minnesota linking Craigslist personals with an increase in reported HIV cases, it may be a good time to review this disease that has, in a way, fallen under the radar for many individuals. What is HIV? Where does it come from? How can you protect yourself? These are all questions that everyone should know how to answer.

What is HIV?

HIV is the initialism for human immunodeficiency virus. This virus is a type of retrovirus that causes AIDS, or acquired immunodeficiency syndrome. This disease causes progressive loss of immune system function, which can result in infections and cancers.

How does HIV damage the immune system?

HIV attacks certain immune system cells and directly or indirectly causes their death. When the number of these cells gets too low the individual loses cell-mediated immunity, which is a part of the immune response that does not use antibodies.  Without cell-mediated immunity opportunistic infections can take hold.

What are the symptoms of HIV?

Many people with HIV aren’t even aware they have the virus. Symptoms generally appear about a month or two after infection, but they can be so mild that they go unnoticed. These symptoms include: fever, fatigue, diarrhea, coughing, weight loss, shortness of breath, and swollen lymph nodes. The swollen lymph nodes are often the first signs of HIV infection. Some people describe it as “the worst flu ever.”

Without treatment HIV will progress and symptoms may include shaking chills, fever, night sweats, lesions of the tongue and mouth, blurred vision, and skin rashes. Over time cancers and opportunistic infections will develop and will be the cause of death if untreated.

How does someone contract HIV?

HIV can be spread through unprotected sexual intercourse (oral, anal, or vaginal), through blood transfusions (US hospitals screen for HIV to prevent this), sharing contaminated needles, and through pregnancy or breast-feeding. The virus is present in blood, semen, vaginal fluid, pre-ejaculate, and breast milk.

When does HIV become classified as AIDS?

The current standard for diagnosing AIDS is: a positive HIV test along with a CD4 cell count below 200, AND the presence of an AIDS-defining complication. This complication can be a disease like pneumocystosis, tuberculosis, toxoplasmosis, or many others.

How is HIV treated?

There is no cure for HIV or AIDS, but many drugs can be used to manage symptoms. Physicians usually prescribe multiple different types of medication to avoid developing HIV strains that are immune to single drugs. Treatment involves taking multiple pills at certain times every day for the rest of the patient’s life. These drugs can in turn cause their own side effects and if other health issues are present they may interfere with the individual’s ability to tolerate treatment.

Treatment can help a person life a normal life span, but without treatment life-expectancy is only 3 years.

How can I protect myself from HIV?

There is no vaccine available for HIV, but there are other methods you can use to protect yourself. The biggest way you can protect yourself is to use a new condom every time you have sexual intercourse (either vaginal or anal) and use a dental dam during oral sex. There is a drug called Truvada that MAY reduce the risk of sexually transmitted HIV if you are a high-risk individual (have unprotected sex, use IV drugs, are an uncircumcised male, or have another sexually transmitted disease.)

You should also use a new, clean needle every time if you are injecting drugs. There are needle-exchange programs available in many communities that you can use. Even better – seek help for your drug use.

If you are HIV-positive be sure to inform your sexual partners. If you become pregnant you need to speak to your doctor immediately about treatment to reduce the chance of passing the disease on to your baby.

Hospital-acquired Infections

03rd Feb 2015 Diseases, News and Events, Viruses

Hospital-acquired infections have once again found a place in the news. Thirty-two individuals are reported to have been infected by a number of different drug-resistant strains of bacteria through contaminated endoscopes.  Eleven of these patients have died, but due to their prior severe illnesses it is unclear whether or not the new infections played any role. The endoscopes in question are called duodenoscopes and are used to treat liver and pancreas illnesses. They are professionally sterilized to high standards between patients, which has unfortunately turned out to no longer be adequate.

The disinfection procedures that the manufacturers recommended were approved by the U.S. Food and Drug Administration (FDA), but after the hospital was able to identify the sterilized scopes as the source of infection they had to switch to a method that exceeded the national standards. The FDA is working with the endoscope suppliers and medical centers to develop new solutions, but this is not the first time scopes have been identified as a source of nosocomial infections. Pittsburgh in 2012 and Chicago in 2014 both saw hospital-acquired infections due to contaminated endoscopes, but luckily there were no fatalities.

The most well-known hospital-acquired infection is Methicillin-resistant Staphylococcus aureus, or MRSA. MRSA originated in the hospital setting, but has expanded to locker rooms, livestock, prisons, military barracks, and homeless shelters. Since many of the individuals infected have weakened immune systems they are already at a greater risk of nosocomial infections. In addition, MRSA’s resistance to certain antibiotics (like penicillins and cephalosporins) make it very difficult to treat.

One of the drug resistant strains of bacteria responsible for the infections in Seattle include Carbapenem-resistant enterobacteriaceae (CRE). Two examples of CRE include Klebsiella species and Escherichia coli (E. coli). While these are normal human gut bacteria, they can cause infection in those undergoing invasive treatments due to illness (like the endoscopes) or those that are taking long courses of antibiotics. Many strains of CRE have become resistant to most of the available antibiotics, making them especially deadly.

How can you protect yourself from hospital-acquired infections, like MRSA and CRE? Most of the prevention is done by the hospital – sterilizing equipment, using appropriate isolation procedures, washing hands, wearing gloves, sanitizing surfaces, wearing aprons while treating patients, and even using antimicrobial surfaces like copper bedrails. For patients that want to protect themselves there is a list of questions you can ask your healthcare provider that is provided by the Centers for Disease Control and Prevention:

Saint Louis Encephalitis

31st Oct 2014 Diseases, Medical News, Viruses

Over the summer there have been mentions of Saint Louis encephalitis virus (SLEV) in regards to Pinellas County. This virus is a flavivirus – a group that includes West Nile – and has the potential to cause severe illness or death in older adults. The name of this disease comes from a particularly extensive outbreak that occurred in St. Louis, Missouri and the surrounding St. Louis County in 1933. Due to the high number of cases NIH was able to investigate and isolate this previously unknown virus. It is thought to have originated in northern Mexico and have been carried north by birds. Pinellas County Mosquito Control uses sentinel chickens to monitor for Saint Louis encephalitis and other arboviruses, since birds are usually the source of infection for mosquitos. Blood is drawn from the chickens weekly and tested for antibodies to the viruses of concern. Fortunately for the chickens they do not develop any symptoms, although once they test positive they have to be removed from the program since they will always carry the antibodies. Sentinel chickens from Pinellas County have tested positive for Saint Louis encephalitis in late July as well as August and into September. Regions with confirmed SLEV include Cross Bayou, Walsingham Park, Sawgrass Lake Park, and Lake Maggiore. While it is more common during hot and humid months, Saint Louis encephalitis can occur year round. Most individuals that are infected have no symptoms, but in rare cases it can manifest with such signs as fever, headache, nausea, vomiting, and fatigue. Severe infections can result in high fever, neck stiffness, disorientation, confusion, tremors, coma, and sometimes convulsion, spastic paralysis, and death. Older adults are at a greater risk for fatal disease. Since there is no cure for Saint Louis encephalitis the only treatment available is supportive care. If you or anyone you know shows symptoms of this disease be sure to talk to your health care provider for proper diagnosis. Since this virus is spread by mosquitos you should take the appropriate precautions. Wear insect repellent and protective clothing and be sure to avoid areas with high mosquito populations. Drain standing water, change pets’ water dishes and birdbaths regularly, and maintain your pool’s water balance to prevent mosquitos from breeding. If you use rain barrels be sure to cover them with fine mesh. Ornamental ponds can be stocked with fish that eat the mosquito larvae and any ornamental bromeliads should be flushed with fresh water regularly and treated with a larvicide. Mosquito Control field technicians can respond to concerns by use of the Mosquito Control Request form found on the Pinellas County website.

The Ebola Virus and the Case for Modern Medicine

07th Aug 2014 Ebola, Viruses

Newspapers throughout the world have been carrying news of the recent outbreak of Ebola. According to the World Health Organization 932 people have been killed thus far, the majority of them in Africa. This disease has taken the lives of at least 100 health care workers trying diligently to bring health back to the infected. These efforts have not been in vain as over 1,700 people have been infected since the outbreak began with around 54 percent of these cases resulting in death.

What you need to know about the Ebola virus.

Ebola primarily occurs in Central and West Africa near the rainforest. Outbreaks generally start when an animal infects a human. This could be in the form of a bite, their feces, secretions, bodily fluids, etc. Fruit bats are notorious for carrying the disease. Once it comes in contact with humans, it is passed person to person. This is not an airborne disease so it cannot spread by simply coughing around another person. There must be some type of fluid exchange for the disease to spread. This can happen via direct or indirect contact with bodily fluids, blood, treating people that are infected, and handling dead bodies.

By understanding how the disease is transmitted, it is easier to avoid becoming infected if you are in an area where an outbreak is occurring. Unfortunately, many of these smaller villages do not have access to this information or basics like clean water which would allow them to live in more sanitary conditions where the risk of infection is reduced.

Once a person becomes sick there are several signs that it could be Ebola. They start to run a high fever, feel weak, headache, muscle pain, and sore throat. These symptoms are very similar to the flu which makes it even harder to identify. Unfortunately, the symptoms do not manifest right away. It can take two to 21 days before a person knows that they are sick. The disease can live inside of a person for 61 days after becoming contaminated, creating additional risk for mass exposure. Very often, people go about their lives not knowing that they could be spreading a deadly disease.

Modern Medicine

As a doctor and humanitarian, Dr. Dean has traveled the world providing the gift of hearing to those in need. This is one of the many ways that he is using modern medicine to transform lives of individuals and their community. The Ebola virus demands a similar approach. Modern medical care can prevent many people from dying from the disease. Access to basic solutions like IV fluids in a contained hospital wing can save lives and prevent the disease from spreading.

Dr. Dean is also keenly aware of the need to prevent outbreaks in the first place by training local community leaders on how to identify the disease and ensure that infected individuals are quarantined and treated right away. People in West Africa and throughout the world can benefit from receiving education on how to avoid coming in contact with the disease, then understanding what to do when symptoms develop. Humanitarians, like Dr. Dean, can play a critical role in stopping this disease by developing educational and treatment programs then training local leaders. For those fortunate enough to live in the United States, focusing on good hygiene is an easy way to avoid disease like this since they require a person coming in direct or indirect contact with an infected persons bodily fluids.