Saturday, July 31, 2010

Reptile feed recalled due to Salmonella

The US Food and Drug Administration (FDA) have announced the recall of frozen reptile feed which includes mice, chicks and rats, because of the risk of Salmonella.

The recall by MiceDirect of Cleveland Georgia initiated the recall. The company distributes the reptile feed to pet stores and by mail order and direct delivery in every state except Hawaii.

According to the recall alert, human illnesses that may be related to the frozen reptile feed have been reported in 17 states.

The company will start irradiating the reptile feed beginning 07/24/2010. It will be irradiated in a similar manner as raw food for human consumption in order to address the Salmonella issue associated with these products.

The infected people could have acquired the infection directly from the food or indirectly from the reptile.
Rodents are not often thought about as sources of human salmonellosis but can be a reservoir for Salmonella.

It has been reported that an outbreak due to MiceDirect products began initially in Great Britain in 2008 where 400 people were stricken with salmonellosis.

Salmonella is an organism which can cause serious and sometimes fatal infections in young children, frail or elderly people, and others with weakened immune systems. Healthy persons infected with salmonella often experience fever, diarrhea (which may be bloody), nausea, vomiting and abdominal pain.

In rare circumstances, infection with salmonella can result in the organism getting into the bloodstream and producing more severe illnesses such as arterial infections (i.e., infected aneurysms), endocarditis and arthritis.

FDA Recall Alert


 

What is the latest on the hippo die-off in Uganda?

A story I initially reported on back in mid-June was about hippos in the Queen Elizabeth National Park in Uganda suddenly dying, at that time a total of 27 had perished to what authorities believed to be anthrax.

About a week later, laboratory testing had confirmed that the culprit was indeed Bacillus anthracis, the agent of the deadly disease anthrax.

So what do we know about this tragic situation a month and a half later?

The latest reports out of Uganda say that the number of hippos that have died as a result of anthrax is up to 82. In addition, nine buffaloes have also died from the bacterial infection.

There is some disagreement among the experts on why this is happening. One side believes that the widespread mortality may be a result of the communal scavenging or ‘cannibalism’ of carcasses of anthrax-killed hippos by other hippos.

But others look to the over-crowding of hippos in the park as the cause of this outbreak. Over-population leads to fights over resources and anthrax can be spread via battle wounds is the argument.

I will continue to keep an eye on new developments in this story.

Thursday, July 29, 2010

Legionella outbreak at Michigan Air National Guard Base

What is the source of a legionella outbreak at a Michigan Air National Guard (ANG) Base? Well that’s what officials at Selfridge ANG Base are trying to determine.

According to a report in thetimesherald.com, at least 31 people have been sickened by the bacteria with at least two people coming down with the severe respiratory disease, legionnaire’s disease.

The two people diagnosed with legionnaire’s disease were a member of the Michigan ANG and a civilian employee from TACOM Life Cycle Management Command based out of Warren, Michigan.

Six people have been hospitalized and released. Legionnaire’s disease is caused by the bacterium, Legionella pneumophila and can be treated with antibiotics.

So what do the other ill people have if not legionnaire’s disease? They likely have Pontiac Fever. Pontiac fever is a self limiting flu-like illness that does not progress to pneumonia or death. Diagnosis is usually made by typical symptoms in an outbreak setting.

The symptoms of Pontiac Fever include fever, malaise and muscle aches. Symptoms resolve in 2-5 days without antibiotic treatment.

Legionnaires’ disease gained national notoriety in 1976 when the Centers for Disease Control and Prevention (CDC) discovered it during an epidemic of pneumonia among American legion members at a convention in Philadelphia.

The primary place in nature it’s found is water sources particularly at warmer temperatures; lakes, rivers and moist soil.

It is also found in man-made facilities (frequently the source of outbreaks) such as air-conditioning ducts and cooling towers, humidifiers, whirlpools and hospital equipment.

People get exposed through inhaling infectious aerosols from these water sources. There is no transmission from person to person.

Legionnaires’ disease is the cause of pneumonia where a non productive cough is typical. Fatality rates of this form of the infection are around 15 % even with improvements in treatment.

Diagnosis of Legionnaires’ disease depends on identifying the bacteria in microbiological culture, detecting the antigen in urine samples or a fourfold increase in antibody titer.

Certain health conditions make you more susceptible to legionnaire’s disease to include increasing age, smoking, chronic lung disease, malignancy and diabetes mellitus, while there are no pre-disposing factors for contracting Pontiac Fever.

Currently on the Air Base, two building are closed for sanitizing and water and air tests are pending.

 

Tuesday, July 27, 2010

Malaria epidemic in the Bicol Region of the Philippines

According to the web site ReliefWeb.int, the Department of Health in Bicol has declared a malaria epidemic in Camarines Norte. Reports say that 182 people have been stricken by the mosquito borne parasitic disease.

Most cases have occurred in the town of Jose Panganiban, however in an effort to prevent the spread of disease, the entire province has been declared an epidemic.

DOH officials report that the majority of victims of malaria were children and the elderly. Approximately 20 percent of those infected were members of a tribal community.

The report did not specify what type of malaria is the cause of the epidemic.

Malaria is a serious parasitic disease transmitted my mosquito bites.

 

Monday, July 26, 2010

New device for detection of serious molds available for homeowners

Homeowners are increasingly more aware of the dangers of certain species of mold that can grow and produce serious toxins. This is especially true in areas where high humidity or in homes that have water damage where mold can thrive.

Some of the more serious molds that are concerns for homeowners are Stachybotrys, Penicillium and Aspergillus. Each of these molds can produce serious toxins that can be a health hazard to people and make the house uninhabitable for people.

Universal Detection Technology of Beverly Hills, a company known for developing early warning technologies for detecting agents of bioterrorism, has developed a consumer ready hand held mold detection device that can detect the three types of molds above.

It detects only the molds of most serious concern to homeowners; Aspergillus, Penicillium and Stachybotrys such as Stachybotrys chlorohalonata, Stachybotrys microspora, Stachybotrys echinata and Stachybotrys chartarum, in addition to certain Aspergillus and Penicillium sub-species.

According to a press release the device contains a technology that is known as immunochromatographic assays.

Specific features of the mold detection device include:

• Separate detection of Aspergillus / Penicillium from Stachybotrys
• Accurate results in as little as 15 minutes.
• Detection below 105 or 100,000 spores per ml.
• No cross-reactivity to 100s of near neighbor strains.

Saturday, July 24, 2010

Increases in babesiosis seen in New York according to DOH


A relatively rare tick borne parasitic infection is being reported with increased frequency in New York’s Lower Hudson Valley according to the New York State Department of Health and infectious disease physicians in the area.

This includes the counties of Westchester, Putnam, Orange, Dutchess, Ulster, Sullivan and Rockland.
According to Dr. Gary Wormser, Chief of Infectious Diseases at Westchester Medical Center, “The number of cases reported annually in just this area has increased from around 5 in 2001 to nearly 120 in 2008."

Like Lyme disease, babesia is transmitted via the bite of a deer tick. The diseases are occasionally seen as co-infections. Babesia can also be transmitted through blood transfusions.

This parasitic disease of the red blood cells (like malaria) can be found worldwide, however most documented cases have been found in the United States. Most human infections are attributed to the species, Babesia microti, while other species are less often seen in zoonotic infections.

It is seen most frequently in the Northeast (Connecticut, Massachusetts, New Jersey, New York and Rhode Island) and to a lesser extent in the upper Midwest (Minnesota and Wisconsin).

The parasite is typically transmitted through a tick bite, Ixodes scapularis in the U.S., from late spring to early fall.

Depending on host factors (people without a spleen, immunocompromised) the disease can range from asymptomatic to life threatening.

Symptoms if present typically appear as non-specific flu like symptoms, fever, chills, body aches, and hemolytic anemia.

Laboratory diagnosis of acute cases is by identifying the parasite within red blood cells microscopically. It is sometime difficult to differentiate from the malaria parasite (Plasmodium falciparum).

If you live in Babesia endemic areas, prevention is through rodent control (deer mice and other small mammals) and the use of tick repellent.

TB breathalyzer shows promise in field test


Tuberculosis, the highly infectious disease that is spread from person to person by infected aerosols is believed to be responsible for more adult deaths than any other infectious disease.

One company has come up with a novel approach for early detection of shedding of M. tuberculosis in cough.

According to a study published in BMC Infectious Diseases, researchers from the Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine field tested the TB Breathalyzer, (Rapid Biosensor Systems of Cambridge, England), in the outpatient clinic of Adama Hospital, Ethiopia.

Sixty individuals were each subjected to a breathalyzer test. The procedure was well tolerated and for each patient the testing was completed in less than 10 min. Positive breath test results were recorded for 29 (48%) patients. Of 31 patients with a diagnosis of tuberculosis 23 (74%) were found positive for antigen in their breath and 20 (64%) were smear positive for acid fast bacilli in their sputum. Six patients provided apparent false positive breathalyzer results that did not correlate with a diagnosis of tuberculosis.

How does the TB Breathalyzer work?

According to Rapid Biosensor Systems web site:

The TB Breathalyser is in integrated system comprising a single-use disposable sample collection tube (measuring 10cm in length and 3.5cm in width) and a multi-use reader. After being nebulised (if necessary) using a 0.9% saline solution, the patient then coughs into the collection tube, at the bottom of which is a glass bio-sensor coated with a patented bio-chemical coating formulated to react with the TB bacilli. A simple push-and-twist action automatically seals the aerosol sample in the tube and deposits it on the bio-sensor. The tube is then inserted into the reader and twisted to switch on the unit.

The TB Breathalyser analyses the patient’s sample by performing a displacement assay employing evanescent wave technology, an established biochemical process that is proven and fast. The reader unit incorporates a diode laser that interrogates the bio-chemical coating carrying the sample. The coating contains analogues that are coated with a fluorescent material. In the displacement assay process, the TB antigen displaces fluorescently-coated analogues and bonds more strongly to antibodies, causing a reduction in the fluorescent signal after excitation by the laser. The laser detects this signal change and the unit returns a positive result. Reading and analysis of the sample takes approximately two minutes, and from start to finish, the entire screening process takes just a few minutes. After use, the sample tube is destroyed.

According to the researchers, the Breathalyzer test shows considerable promise as a tool to investigate shedding of M. tuberculosis in cough. Further study is required to determine the sensitivity and specificity of the test and the relationship of excreted Ag85B with smear positivity. These preliminary findings suggest that although this novel testing device cannot replace sputum microscopy it might assist in the early identification of TB cases that cannot expectorate sputum for examination. Further study should be undertaken to assess its value in populations with restricted access to healthcare and where screening for early tuberculosis disease using conventional tools is not currently possible.

Wednesday, July 21, 2010

Doctor, med student contract pneumonic plague from patient

Doctors in Trujillo, Peru are attempting to save the lives of 3 people including a resident doctor, a medical student and the patient they had contact with.

The patient, a woman from a town north of Trujillo, was brought to the Regional Teaching hospital by her family.

She presented with severe pneumonia, fever and other symptoms and was treated for pneumonia and H1N1 with antibiotics and antivirals respectively.

However, even after treatment there was no improvement. An unspecified “rapid test” for pneumonic plague was negative.

The resident doctor who intubated and treated her came down with the same symptoms. He has been treated and is in critical condition with multi-organ failure.

In addition, a 4th year medical student who also had contact with the patient with similar symptoms came up positive for a test (same rapid test?) for pneumonic plague.

The Regional Manager of Health, Victor Peralta Chavez said that this patient’s condition is “delicate”.

Pneumonic plague is probably the most serious form of plague and it occurs when the bacteria infect the lungs and cause pneumonia. It is contracted when the bacteria is inhaled (primary) or develops when bubonic or septicemic plague spreads to the lungs.

Pneumonic plague is contagious and can be transmitted person to person. It is highly communicable under appropriate climate conditions, overcrowding and cool temperatures. Untreated pneumonic plague is frequently fatal.

 

Tuesday, July 20, 2010

It’s International Group B Strep Awareness Month: What are the complications of Group B Strep

Group B beta-hemolytic streptococci, or Streptococcus agalactiae, are normal flora of the lower intestinal tract and female genital tract in up to 35 percent of women. Colonization of the vagina with group B streptococci typically is an indication of contamination from the rectum. In the woman, vaginal colonization with group B streptococci is usually asymptomatic. However, the presence of the bacterium in the female genital tract during the time of childbirth can lead to infection of the newborn.

Early-onset Disease
The bacterium that is colonized in the vagina at the time of birth can result in severe neonatal disease. The organism is acquired by the neonate in utero before delivery either through ruptured fetal membranes, or during passage through the colonized birth canal. Early-onset disease usually happens during the first week of life, with many infants becoming ill within 24 hours after birth. The disease presentation in the newborn with early-onset disease is characterized by signs and symptoms of bacteremia (bacteria in the blood) and pneumonia. Though all infants are susceptible, the attack rate and death rate is higher in preterm than in full-term infants.

Late-onset Disease
Late-onset disease from group B streptococci in the newborn usually becomes evident between one week and several months after birth, with an average time of about a month. More than half of infected newborns get infected from the birth canal of infected mothers; some cases are acquired from the mother or other caregiver. Meningitis is the predominate clinical disease associated with late-onset disease. Many children with late-onset meningitis end up with neurological complications. Other complications from group B streptococci in the newborn child include hearing loss, vision loss and mental retardation.

In the Mother
Group B streptococcal infections may also happen to the mother. Among the more serious complications are postpartum endometritis, post-cesarean wound infections and bacteremia, pre-term labor and sepsis.

Prevention
Given the severity of group B streptococcal infections in newborns, the Centers for Disease Control and Prevention--in conjunction with the American Academy of Pediatrics and the American College of Obstetrics and Gynecology--issued a protocol of antibiotic administration during labor and delivery. The use of penicillin during labor reduces the risk of neonatal infection by removing the colonized group B streptococci. In addition, a microbiological culture protocol was established testing the mother's vagina and rectum at Weeks 35 and 37 of gestation. These protocols have decreased group B streptococcal infections in newborns dramatically.

Group B Strep International
 

Monday, July 19, 2010

With summer comes swimming and the risk of swimmer’s itch

It doesn’t matter if you are at an ocean beach or swimming in a fresh water lake, if there are infected birds or mammals and the suitable snail there could be parasitic larva in the water that could burrow in your skin.

Swimmer’s itch is caused by the larvae of a parasite called schistosomes. A number of birds like ducks and gulls and some mammals like beavers can be infected with the parasite in their blood.

*These schistosomes are not the same as the ones that cause schistosomiasis in many parts of the world.

So how do these parasites get into the water that I swim in? If the feces of these infected critters find there way to water, the parasite’s eggs found in the feces will hatch releasing free-swimming larvae which in turn search for a specific species of snail.

If the right snail species is present in the water and the larvae find it, the larvae penetrate the snail to continue its life cycle. Swimmer’s itch is also called cercarial dermatidis because the next stage of the parasite, the cercariae, is released from the snail looking for its final host (bird or mammal mentioned above) to complete its life cycle.

However, sometimes the cercariae instead penetrate the skin of a human and cause a rash and an allergic reaction.

Because humans are not the appropriate final host for the development of the parasite, the cercariae will die in about a week without further disease.

The symptoms of swimmer’s itch may include tingling or itching of the skin, blisters or small pimples. These symptoms typically last about a week and gradually go away.

Scratching the affected skin should be avoided since it can result in secondary bacterial infections.

The following recommendations will help reduce your chance of getting swimmer’s itch:

1. Do not swim in areas where swimmer's itch is a known problem.
2. Do not swim near or wade in marshy areas where snails are commonly found.
3. Towel dry or shower immediately after leaving the water.
4. Do not attract birds (e.g. by feeding them) to areas where people are swimming.

Swimmer’s itch rarely requires medical attention and the itch can be relieved by using Calamine lotion, cool compresses, bathing in Epson salts and the use corticosteroid creams.

 

Sunday, July 18, 2010

More than 100 sick after taking malaria drugs in China: an issue of tainted drugs?

It has been reported by Xinhuanet.com that one child has died and more than 100 people are sick after taking malaria medication in the Sichuan province of southwest China.

According to the report, 143 people took two malaria drugs, chloroquine and primaquine and soon after complained of exhaustion and nausea. 98 people were hospitalized for the illness.

The medication was provided by the Chinese CDC and a local hospital.

So the question remains, what caused the majority of people taking these drugs to get sick?

As the experts at Promed have said, G6PD deficiency is endemic in SW China and the malarial drug primaquine can cause hemolysis in people with this condition. However the number of sick people is to extreme to be explained away by G6PD deficiency.


 

Saturday, July 17, 2010

Cebu DOH cautions citizens of diarrheal diseases with the arrival of rainy season

Diarrheal diseases through contaminated water are an issue during heavy rainfalls especially where wells and similar water sources are the supplier of drinking water.

The latest incident in Barangay Calmante in Tudela, Cebu, Philippines where in the course of one week, 55 people have been stricken with waterborne diarrheal diseases has caused Department of Health Environmental Health Program Coordinator Engr. Evangeline Canoneo to issue some warning and recommendations to the public.

As far as collecting and storing water from artesian wells, Canoneo explains, “to first boil the water for three to five minutes and store the water in a clean container.”

She also advised on basic elements of hygiene like handwashing before and after eating and after using the toilet is vital to prevent the risk of infection.

For people who get their water from a refilling station, she tells the public to check whether the bacteriological test certificate is updated as this is done on a monthly basis. You want to ensure the water has been tested and are free of fecal coliforms.

Fecal coliforms are bacteria like E.coli, which may not be directly harmful to people, however it may indicate that the water has been contaminated by either human or animal waste and could contain intestinal pathogens.

Common waterborne diseases that could cause diarrhea include but are not limited to; typhoid, cholera and amoebiasis.

 

Friday, July 16, 2010

Vet warns that summer is the season for tularemia, especially in cats

This is according to Kansas State University veterinarian Brad DeBay who says that the summer months are when they see increases in the deadly bacterial diseases tularemia in animals but especially in cats.

This is also an issue for humans as tularemia is a zoonotic disease and people can also get infected.

According to DeBay, "Most cases I know of where it has been transmitted to humans have been through a bite wound."

Cats usually get infected with tularemia through eating infected rabbits or through the tick bite from infected fleas.

Clinical signs in cats with tularemia include lethargy, anorexia and fever. It also is possible for a clinically healthy cat to transmit the disease if the organism is present in its mouth, even if the cat hasn't yet developed symptoms, DeBey said.

Also known as rabbit fever and deer fly fever, this disease of the Northern hemisphere most often occurs during the summer months and mid-winter and correspond with vectors and hunting season respectively.

The disease tularemia is caused by the bacterium Francisella tularensis. This bacterium is found in nature in rabbits, rodents, beavers, squirrels and several domestic and farm animals.

In humans, it is typically an occupational disease (farmers, veterinarians, sheep herders and shearers) and of hunters.

There have been cases where people got infected from a domestic cat. It is believed that cats get the organism from contaminated prey and their mouth and claws become infected.

The disease in people depends on how it’s acquired. After infection, incubation can be a couple of days to weeks, with non-specific symptoms like fever, chills, headache, sore throat and diarrhea.
The way the organism enters the body frequently dictates the disease and degree of systemic involvement. The infection tularemia can be divided into six syndromes:


• Ulceroglandular
This the most common form of tularemia which is characterized by ulcers at the site of the tick bite.
• Glandular
No skin lesions in this infection. Enlarged lymph nodes are present and may require surgical drainage.
• Oculoglandular
This is an infection of the conjunctiva usually by splashes or aerosols.
• Oropharyngeal
The lesion is found in the throat because of ingestion of contaminated water or food.
• Typhoidal
This infection is also due to ingestion of contaminated food and water. This is the only form of tularemia where diarrhea is a prominent characteristic.
• Pneumonic
With a high mortality in this syndrome, this type is most frequently seen in animal associated occupations.
Tularemia is treatable with antibiotics (streptomycin and gentamicin).


DeBey said the best way to prevent cats from contracting the disease is simple: keep them indoors.

He goes on to say, "For people who have cats but don't want to keep them indoors, the next best thing is to control ticks. Unfortunately, there's no way to control a cat from hunting rabbits since that's in their nature, but it's the risk you'll have to take with a cat being outdoors.
 

Thursday, July 15, 2010

Smallpox vaccine for immunocompromised people delivered to the Strategic National Stockpile

The Danish company Bavarian Nordic has delivered the first one million doses of Imvamune, a third generation smallpox vaccine which is safe and effective on people with weakened immune systems.

In the case of a bioterror event providing this vaccine is mandated under the Pandemic and all-Hazards Preparedness Act (PAHPA) to protect this special population of patient.

Bavarian Nordic is contracted to manufacture and deliver 20 million doses through 2013. This is the result of the 2004 Project Bioshield Act which calls for the government to purchase and stockpile vaccines and drugs to fight anthrax, smallpox and other potential agents of bioterror.

Imvamune has been shown to be safe and well tolerated in people with compromised immune systems. It has also been shown to induce a comparable efficacy as ACAM2000, the licensed second-generation smallpox vaccine in the US. However, the CDC points out that people with suppressed immune systems should not take the older vaccine due to the specific risks.

The Strategic National Stockpile (SNS) is the United States' national repository of antibiotics, vaccines, chemical antidotes, antitoxins and other critical medical equipment and supplies. In the event of a national emergency involving bioterrorism or a natural pandemic, the SNS has the capability to supplement and re-supply local health authorities that may be overwhelmed by the crisis, with response time as little as 12 hours.

Tuesday, July 13, 2010

New molecular method for detecting Anisakis in raw fish developed

Raw or undercooked fish used for sushi, sashimi and related foods have always carried some risk for parasites like Anisakis, Pseudoterranova, Contracaecum and Hysterothylacium.

Historically, examination of the fish for these parasitic larvae includes visual examination, transillumination and digestion by artificial gastric juice. But these methods do not allow users to analyse very large species, or be applied to processed products.

Now a team of researchers at the Area of Molecular Biology and Biotechnology of the National Association of Manufacturers of Canned Fish and Shellfish (ANFACO-CECOPESCA) developed a fast and efficient molecular method to detect the parasite Anisakis in all fisheries resources according to a study in the journal Food Control.

According to Montserrat EspiƱeira, co-author of the paper, the method is highly specific and sensitive for the above parasites.

The larvae of Anisakis are found in the muscle and viscera of a number of fish; cod, hake, mackerel, sardines, anchovies, salmon, herring, tuna, whiting, turbot, halibut and haddock plus squid. A number of these fish are used in the preparation of raw sushi and sashimi.

Human infection with anisakiasis can be a painful, gastrointestinal disease with the pain resembling appendicitis.

Monday, July 12, 2010

Woman contracts vaccinia virus through sexual contact with military boyfriend

A Washington State woman became infected with the vaccinia virus after having unprotected sex with her military boyfriend who recently been vaccinated against smallpox. Vaccinia virus (VACV) is the live viral component of smallpox vaccine.

The woman in her 20s sought medical care after the appearance of painful, ring-shaped lesions on her labia. Wisely she told the physician that her boyfriend was in the military and was vaccinated for smallpox and suspected that could be the cause.

However, the urgent care doctor did not consider that in the diagnosis and ran a series of tests for sexually transmitted infections (gonorrhea, Chlamydia and herpes) and was treated for them.

After 3 days of increasing pain and new vaginal sores she sought another opinion from another clinic where samples were collected for herpes and vaccinia virus. A referral to an infectious disease specialist for examination was also provided.

The lesion sample was tested by the Washington State Public Health Laboratory for testing using PCR technology which was positive for orthopoxvirus and nonvariola orthopoxvirus. The CDC Poxvirus program confirmed the presence of vaccinia virus.

 

Sunday, July 11, 2010

A couple of “plague” stories

The plague has been making the news lately coming from a wide array of geographic locations. Here are two such stories.

Out of Myanmar (Burma), according to the paper The Irrawaddy, an unspecified number of Rangoon (Yangon) residents have been diagnosed with the plague.

According to an anonymous source from the Burmese Ministry of Health (MOH), all the infected people were treated with antibiotics and survived the infection.

This is the first time in decades that the plague has been seen in the region.

Some however are concerned about the Burmese governments “cover-up” of the diagnosis of this very important health issue and fear the lack of public information could lead to increased dangers to Burmese residents.

According to an official from the Rangoon Municipal Committee said it had formed special task forces for rat eradication and has killed tens of thousands of rats on a daily basis. However, rat eradication with spraying for the infected fleas could potentially cause increased amount of plague cases as the fleas may then seek out humans to feed on.




And out of Los Angeles County, the US Forest Service has closed the Los Alamos Campground in the Angeles National Forest after a California ground squirrel capture a couple of weeks ago tested positive for the plague.

The park is expected to remain closed for 10 days as squirrel burrows are being dusted for fleas and more testing is being performed.

According to Jonathan Fielding, the county's public health director, visitors to Los Alamos Campground are advised to avoid squirrels and chipmunks and stay clear of animal burrows, which can be hot spots for fleas. "Protection with an insect repellant containing DEET is also recommended for persons visiting the Angeles National Forest and engaging in outside recreational activities in other areas of L.A. County."



Plague is an infectious disease caused by the bacterium, Yersinia pestis. It is found in animals throughout the world, most commonly rats but other rodents like ground squirrels, prairie dogs, chipmunks, rabbits and voles. Fleas typically serve as the vector of plague. Human cases have been linked to the domestic cats and dogs that brought infected fleas into the house.

People can also get infected through direct contact with an infected animal, through inhalation and in the case of pneumonic plague, person to person.

Yersinia pestis is treatable with antibiotics if started early enough.

Bubonic plague is the most common form of plague. In this form the bacteria typically enter the body through the bite of an infected flea or rodent. Here the bacteria infect the lymphatic system. After a few days to week, the person will experience fever, chills, weakness, and swollen lymph glands. These are called buboes.

The other forms of plague are pneumonic and septicemic.
 

Saturday, July 10, 2010

Millions of Venezuelans at risk for contracting Chagas disease

Some experts believe that up 6 million people in Venezuela are at risk of contracting the parasitic infection, Chagas disease because the main vector, the chipo, is found so widespread in the country’s geography.

The chipo, or Rhodnius prolixus, is the primary vector of the parasite and experts believe that over 100,000 square kilometers of Venezuela is common habitat for the chipo. This even includes dozens of populated municipalities.

Chagas disease is traditionally more of a rural disease where people live in poorly constructed homes with cracks and crevices in the walls where the bugs can get through or those with thatch roofs. They can also be found in palm trees and the fronds.

In addition, according to the Venezuelan paper, El Universal, in less than two and a half years, the metropolitan area of Caracas has been affected by three massive outbreaks. A fruit juice was the contamination factor both in the municipality of Chacao and in the town of Chichiriviche de la Costa.

Chagas disease, caused by the protozoan Trypanosoma cruzi, is responsible for a greater disease burden than any other parasitic disease in the New World. Infection occurs when the triatomine vector defecates during its blood meal and fecal material containing the parasite is inoculated through the bite wound or mucous membranes.

The oral mode of transmission of Chaga’s disease is being increasingly recognized in the region. It is associated with the contamination of fresh food or beverages with intestinal contents of triatomid (kissing) bugs.


Thursday, July 8, 2010

Are we one step closer to an HIV vaccine? New discoveries point in that direction

According to research team led by the National Institute of Allergy and Infectious Diseases (NIAID), they have made a major discovery that could impact the prevention or treatment of HIV infection.

The scientists discovered two powerful human antibodies, called VRC01 and VRC02 that has shown the ability to stop more 90 percent of known global HIV strains from infecting human cells in the laboratory.

Another major discovery is the scientists have determined the atomic-level structure of the VRC01 antibody when it attaches to HIV. This allows scientists to define how the antibody works and to precisely locate where it attaches to the virus. This information is crucial in the design of a vaccine.

According to NIAID Vaccine Research Center director, Dr. Gary Nabel, “We have used our knowledge of the structure of a virus—in this case, the outer surface of HIV—to refine molecular tools that pinpoint the vulnerable spot on the virus and guide us to antibodies that attach to this spot, blocking the virus from infecting cells.”

Because of the ever changing mutations of the HIV surface proteins, the virus has shown great ability to evade antibody that can neutralize the virus. The result is many HIV variants worldwide.

However, according to the researchers they have identified a few areas on HIV’s surface that remain nearly constant across all variants. One such area, located on the surface spikes used by HIV to attach to immune system cells and infect them, is called the CD4 binding site. VRC01 and VRC02 block HIV infection by attaching to the CD4 binding site, preventing the virus from latching onto immune cells.

These discoveries out of the NIAID are certainly a step in the right direction for producing a vaccine for HIV and other infectious diseases.

National Institute of Allergy and Infectious Diseases Press Release