Thursday, September 30, 2010

Rat lungworm found on Canary Island of Tenerife

The Institute of Tropical Diseases of the Canary Islands has reported the discovery of the rat lungworm on the island of Tenerife. Though there has not been a complete identification of the lungworm, Angiostrongylus cantonensis is the likely suspect and the species most often seen in human infection.

It is likely the parasite was imported to the island, however it is not clear what product it was imported in.

What is angiostrongyliasis?

It is an infection caused by the rat lungworm, Angiostrongylus cantonensis. This is a parasitic infection in rats where it matures. Mollusks like snails and slugs pick up Angiostrongylus larvae by ingesting them in rat feces.

How do people get this parasite?

Infection is by accidentally or intentionally ingesting raw snails and slugs. Lettuce and other leafy vegetables may also be a source if contaminated by small mollusks. Eating raw or undercooked prawns and crabs that have ingested mollusks may also be a source of infection.

What are the symptoms and disease?

Angiostrongylus cantonensis infection is usually asymptomatic or mildly symptomatic. Symptoms usually appear in 1-3 weeks. The most serious disease is eosinophilic meningitis. The symptoms can include headache, stiff neck, tingling or painful feelings in the skin, low-grade fever, nausea, and vomiting. The spinal fluid exhibits eosinophilia of over 20%. Deaths are rarely reported.

Symptoms may last for weeks to months.

How is this infection diagnosed?

The presence of eosinophils in the spinal fluid and a history of eating raw snails suggest angiostrongyliasis. Finding the worms in spinal fluid or at autopsy is confirmation.

What about treatment?

Treatment is usually not necessary. The parasite dies over time since it can’t mature and complete its life cycle. Usually treatment of symptoms; headache medicine, steroids are all that is needed. Treatment with anti-parasitic drugs is generally ineffective against angiostrongyliasis.

How do you prevent getting angiostrongyliasis?

• Don't eat raw or undercooked snails or slugs.
• Cook crabs and prawns to kill the larvae.
• Thoroughly clean lettuce and other produce.

Wednesday, September 29, 2010

5 people diagnosed with pneumonic plague in Tibet

One person has died and another is in critical condition with the very dangerous form of the plague known as pneumonic plague. The 4 survivors are all had contact with the deceased person are currently under quarantine according to the Tibet health department.

The health department said the outbreak started at Latok village in Tibet's Nyingchi Prefecture. Health officials and disease control specialists have gone to the area in an effort to prevent further spread of the disease.

Probably the most serious form of plague and it’s 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 a rare form of plague accounting for about 1% of all plagues.

According to ProMed, primary plague pneumonia has a short incubation period of 1-3 days, after which there is sudden onset of flu-like symptoms including fever, chills, headache, generalized body pains, weakness, and chest discomfort.

A cough develops with sputum production, which may be bloody, and increasing chest pain and difficulty in breathing. As the disease progresses, hypoxia (low oxygen concentration in the blood) and hemoptysis (coughing up blood) are prominent. The disease is invariably fatal unless antimicrobial therapy commences within 24 hours of exposure.

Pneumonic plague is contagious and can be transmitted person to person. People with primary pneumonic plague generate large quantities of infectious aerosols that pose a significant risk to close contacts. It is highly communicable under appropriate climate conditions, overcrowding and cool temperatures. This is the form that is of concern in China and Tibet today.

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. In China and Tibet, the marmot has been implicated as a source of plague to humans.

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.

There are three forms of human plague; bubonic, septicemic and pneumonic.

In the U.S., there has not been a case of person to person transmitted plague since 1924.

Monday, September 27, 2010

8 arrested for selling counterfeit rabies vaccine

Eight people were arrested Sunday in China’s Guangxi Zhuang Autonomous Region for producing and selling fake rabies vaccine that had killed one and put over 1000 in danger.

Drug authorities in Laibin City say they found 1263 shots of the counterfeit vaccine and these were confiscated. Over 1200 doses had already been administered to unsuspecting patients. Reports disclose that the fake vaccine was produced in an underground workshop and sold for nearly $50,000.

The vaccine scandal came to light when a 4 year old died 3 weeks after being bitten by a dog. The family paid 700 yuan, or over $100 for the complete series of 6 vaccines. The child is the only confirmed victim of this very dangerous scam.

Health clinics in Laibin have located all patients involved and given them free vaccine.

Rabies is a huge problem in China with 2000 people dying annually from the disease.

Sunday, September 26, 2010

The Top 10 Notifiable Infectious Diseases in the United States

The Summary of Notifiable Diseases for the United States was released this summer in the Morbidity and Mortality Weekly (MMWR).

This 100 page document has enough information and data to boggle the mind at first look; however it breaks down reportable diseases data by age, sex, state, race and every other category under the sun into more digestible nuggets. In addition, it also includes data from previous years to use as a comparison.

What is a notifiable disease?

A notifiable disease is one for which regular, frequent, and timely information regarding individual cases is considered necessary for the prevention and control of the disease.

After going through the data, I extracted the following information. Here is the list of the Top 10 reported cases of Notifiable Infectious Diseases in the United States (2008 is the most recent data which was released this summer).

1.Chlamydia trachomatis 1,210,523

2.Gonorrhea 336,742

3.Salmonellosis 51,040

4.Syphilis (all stages) 46,277

5.AIDS 39,202

6.Lyme disease 35,918

7.Varicella (chickenpox) 30,386

8.Shigellosis 22,625

9.Giardiasis 18,908

10.Pertussis 13,278

Saturday, September 25, 2010

Invasion of black flies puts community at risk for river blindness

At least 70 percent of the population of 2500 in the farming community of Asuboi in Ghana has been infected by the parasite Onchocerca volvolus after the area was invaded by the vector, the black fly.

It is reported that the children in this township located in the middle of the Abofour Forest are suffering from skin disorders like rashes and lesions.

An additional problem is the difficulty of getting medical supplies and personnel in the area due to horrible roads leading to the town. The best and easiest way to get to Asuboi is via bicycle or motorcycle, however even these modes of transportation are incredibly dangerous.

The town itself lacks the facilities to perform proper examinations into the parasite.

Onchocerciasisis an infection caused by the parasite Onchocerca volvulus (worm), spread by the bite of an infected blackfly.

It is also called River Blindness because the transmission is most intense in remote African rural agricultural villages, located near rapidly flowing streams.

Persons with heavy infections will usually have one or more of the three conditions: dermatitis, eye lesions, and/or subcutaneous nodules. Superficial skin biopsies will identify the parasite microscopically.

According to the Global Network of Neglected Tropical Diseases, 37 million people are infected with onchocerciasis or river blindness worldwide, the vast majority of people infected living in Africa. 110 million people in 35 countries are at risk of infection. Half a million people are severely visually impaired from this disease, with 270,000 blind.

Friday, September 24, 2010

Schistosomiasis is still endemic in parts of the Philippines

Schistosomiasis was first recognized clinically in the Philippines in the early years of the 20th century. However, unlike some other Asian countries like Thailand and Japan who haven’t seen a new case of the parasite in decades, the Philippines still have many areas where the parasite is endemic.

The latest information from the National Center for Disease Prevention and Control show that schistosomiasis is endemic in 28 of the 79 provinces in the country, particularly among rice farmers and fishermen.

In the Philippines, schistosomiasis is third only to malaria and tuberculosis in terms of causes of morbidity.

There are five species of Schistosoma that cause schistosomiasis in humans; Schistosoma japonicum, S. mansoni, S. haemotobium, S. mekongi and S intercalatum. S. japonicum is the species found in the Philippines.

Schistosomiasis is an acute or chronic disease, produced by parasites called Schistosoma. It is not a single disease, but a disease complex.

The schistosomes are found in fresh water. This water gets contaminated by infected people working in the rice field, fisherman in the lake or children playing who indiscriminately defecate or urinate in the water.

Schistosomes have a very complicated life cycle. The eggs in the feces or urine hatch and the ciliated miracidia swim to the specific snail species where it penetrates and goes through a couple of stages in the snail. After a period, thousands of the infective stage are released and swim around looking for a human to infect.

The free-swimming cercariae are capable of penetrating the unbroken skin of the human host.

In the human the adult schistosomes eventually end up in the blood vessels of the intestines (S. mansoni and S. japonicum) or bladder (S. haemotobium). Here they produce eggs which are the cause of the disease.

The problems with schistosomiasis are many and can include; S. mansoni and S. japonicum: Katayama fever, hepatic perisinusoidal egg granulomas, Symmers’ pipe stem periportal fibrosis, portal hypertension, and occasional embolic egg granulomas in brain or spinal cord. People, especially children are characterized with a large distended abdomen

Distended abdomen is frequently seen in schistosomiasis due to enlarged liver and spleen.

Pathology of S. haematobium schistosomiasis includes: hematuria (blood in the urine), scarring, calcification, squamous cell carcinoma, and occasional embolic egg granulomas in brain or spinal cord.

Schistosomiasis can be diagnosed by identifying the characteristic eggs in stool samples, biopsy of tissue, rectal (all) or bladder (S. haemotobium only). If eggs cannot be found in stool samples, antibody detection tests are available.

The drug of choice is praziquantel for infections caused by all Schistosoma species.

There is not a vaccine or any other prophylaxis available for prevention of schistosomiasis.

Prevention is by:

•Avoiding swimming and other contact in fresh water in areas that are endemic

•Schistosomiasis can also be transmitted through drinking contaminated water. Boiling water for 1 minute will kill the parasite.

•Untreated piped water coming directly from canals, lakes, rivers, streams or springs may contain cercariae, but heating bathing water to 50° C (150° F) for 5 minutes or filtering water with fine-mesh filters can eliminate the risk of infection. In addition, allowing bath water to stand for 2 days is effective because cercariae rarely remain infective longer than 24 hours.

Thursday, September 23, 2010

Outbreak of pink eye in schoolchildren blamed on eye exercises | video

School districts in Xiamen, China have seen a large increase in the number of cases of conjunctivitis with some hospitals seeing up to 50 patients a day.

Some schools have canceled doing eye exercises since it is suspected that this can cause cross-infection among students especially during the fall which is peak “pink eye” incidence.

During eye exercises the eyes may be closed and massaged with circular movements of the fingers for 1-2 minutes, which provides an opportunity for infection of the eyes if hand washing has been neglected.

Conjunctivitis is a common eye condition worldwide. It causes inflammation (swelling) of the conjunctiva -- the thin layer that lines the inside of the eyelid and covers the white part of the eye. Conjunctivitis is often called "pink eye" or "red eye" because it can cause the white of the eye to take on a pink or red color. The most common causes of conjunctivitis are viruses, bacteria, and allergens.

Wednesday, September 22, 2010

Number of cases of anthrax in Bangladesh rises to nearly 600 in a month

According to Bangladesh’s Institute of Epidemiology, Disease Control and Research (IEDCR) the total number of cases of cutaneous anthrax has reached 589 since the first case appeared in Sirajganj on August 18.

In the past 24 hours alone, the IEDCR has reported 4 new cases in the Meherpur and Narayangonj districts.

Since the anthrax cases have occurred in 12 of the 64 districts in the country, the Bangladeshi government had announced a red alert in the country as is trying to coordinate anthrax prevention and treatment in all 64 districts.

Anthrax is caused by the bacterium, Bacillus anthracis. This spore forming bacteria can survive in the environment for years because of its ability to resist heat, cold, drying, etc. this is usually the infectious stage of anthrax.

Anthrax is a pathogen in livestock and wild animals. Some of the more common herbivores are cattle, sheep, goats, horses, camels and deers.

It infects humans primarily through occupational or incidental exposure with infected animals or their skins.

What is cutaneous anthrax?

This form of anthrax disease occurs when the spore (or possibly the bacterium) enters a cut or abrasion on the skin. It starts out as a raised bump that looks like an insect bite. It then develops into a blackened lesion called an eschar that may form a scab. Lymph glands in the area may swell plus edema may be present. This form of anthrax responds well to antibiotics. If untreated, deaths can occur if the infection goes systemic. 95% of cases of anthrax are cutaneous.

Other forms of anthrax include inhalation and gastrointestinal.

Diagnosis of anthrax is made on culture of the bacteria (see picture). There are also molecular and serological methods available. Chest X-ray can also help in the diagnosis of inhalation anthrax.

Anthrax can be treated with antibiotics with varying rates of success based on how quickly treatment starts and the type of anthrax. Ciprofloxacin, doxycycline and penicillin are antibiotics for the treatment of anthrax in adults and children.

Saturday, September 18, 2010

The four cardinal signs of inflammation

Yesterday a friend of the family asked me to look at something on her lower shin to get my opinion as to what it was. It was raise, red and slightly more than 1 inch in diameter. It felt warm especially in comparison to non-red areas of the shin. Certainly she had some localized type of infection. She should have a doctor look at it.

I guess what I find funny looking back on it is my mindset when checking her possible infection is that something I was taught years ago remains with me to this day like I heard it yesterday: the four cardinal signs of inflammation.

Early Greek and Roman physicians recognized these signs as:

•Dolor (pain)
•Calor (heat)
•Rubor (redness)
•Tumor (swelling)

Due to the release of certain chemical mediators we get calor and dolor; the result of increased blood flow with blood vessel congestion. Dolor and tumor are the result of increased permeability of blood vessels with blood and fluids escaping outside the vessels.

These signs are easily recognizable signs of a localized infection. The formation of pus in which neutrophils (white blood cells) are attracted to the area any also escape the blood vessels are another sign of localized infection.

How was this infection acquired? Not sure, but it could be the result of a number of things; a minute break in the skin (from shaving for example), ingrown hair, or an insect bite. The list is nearly endless.

I’ll always remember dolor, calor, rubor and tumor.

Friday, September 17, 2010

Soil amoeba blamed in the deaths of two organ transplant recipients

Two patients who received solid organ transplants in Arizona have died as a result of a parasite they got from the donated organs.

One man, a liver recipient and another who receive a kidney and pancreas died as a result of transplant-related encephalitis due to the microscopic amoeba, Balamuthia mandrillaris. Two other recipients of organs from the same donor, a heart and a kidney donor are alive and are not presenting with symptoms.

This is the second cluster of transplant-related encephalitis due to B. mandrillaris in less than a year. Last December there was another cluster in Mississippi where one kidney recipient died and another went into a coma and later recovered.

B. mandrillaris is a microscopic amoeba found in the environment in soil and has been isolated from humans and animals (horses, dogs and sheep) at autopsy.

The amoeba enters the respiratory system or through the skin and from there it can invade the central nervous system through the bloodstream causing granulomatous amebic encephalitis (GAE) in those with compromised immune systems.

It can be especially dangerous to people undergoing organ transplants, whose immune systems are purposely weakened so their bodies don't reject their new organs.

Human infections with this amoeba are extraordinarily rare with only 150 cases reported worldwide in the past two decades.

Balamuthia is one of several agents of severe or fatal encephalitis along with West Nile virus, and rabies that have been transmitted through organ transplantation in recent years

Organs for transplant are routinely tested for a variety of infectious diseases (HIV, hepatitis B and C among others) prior to transplantation. However, very rarely an unusual organism shows up that’s not tested for. Organ donors are screened through medical history, etc to identify infectious risks. However, creating standards that eliminate all risk for infectious disease transmission is not feasible.

Wednesday, September 15, 2010

Man returns from African hunting safari infected with sleeping sickness

A man who returned from a hunting safari in Zambia last month has been diagnosed and treated for African sleeping sickness.

Dr. Devon Hale of the Salt Lake City GeoSentinel Site reports that the man traveled to Zambia on a hunting safari at a reserve in the South Luangwa river valley in Eastern Zambia.

The individual was diagnosed with the parasite Trypanosoma brucei rhodesiense by examination of the peripheral blood. There was no central nervous system involvement. The patient was treated successfully with suramin and released.

Travelers returning from Zambia with sleeping sickness are quite rare. The last documented case was in 2000 of a British traveler who went on a game-viewing vacation. It’s been even longer since a returning US traveler from Zambia was found to be infected with the deadly disease.

One of the true tropical diseases, African sleeping sickness is endemic only in sub-Sahara Africa bounded by 15° North and South latitudes.

Two varieties of African sleeping sickness exist: one primarily in East Africa caused by the parasite Trypanosoma brucei rhodesiense. T.B. rhodesiense produces an acute infection that will usually cause severe illness and death in weeks to months.

The other species is Trypanosoma brucei gambiense. This parasite is found in West and Central Africa. However, the 2 species are showing some geographic overlap.

This infection progresses more slowly and may require months to years for disease to occur.

Both types of sleeping sickness are caused by the bite of a tse tse fly. These vicious little bugs depend on blood meals for its nutrients. It gets the blood from mammals including humans. The tse tse fly has a very painful bite and a traveler will certainly remember getting bit.

When taking a blood meal, the fly injects the parasite into the skin. From here the parasite is carried to the lymphatic system and eventually the bloodstream.

They go through stages in the body and eventually end up in the spinal fluid if appropriate, timely treatment is given. The treatment options for sleeping sickness depends on which stage the disease is in, blood stage or CNS stage. Treatment should begin as soon as possible.

Diagnosis of African sleeping sickness is based on finding the parasite in blood , spinal fluid or lymph node aspirates.

Tuesday, September 14, 2010

Microbiology 101: the Gram stain

The Gram stain: even many lay people have heard of this basic but incredibly important test that serves an integral role in the microbiology laboratory. Here I would like to give a brief overview over the basics of the Gram stain.

The staining procedure for bacteria was discovered over 100 years ago by Hans Christian Gram. Almost all clinically important bacteria can be detected using this stain. Exceptions are few and include intracellular bacteria like Chlamydia, bacteria that lack a cell wall such as mycoplasma and spirochetes like Treponema which due to their dimensions cannot be resolved by a light microscope.

The Gram stain divide bacteria into two major categories; gram positive, which takes up and retains the primary stain, and gram negative, which the primary stain can be washed out by a decolorizing acetone-alcohol.

How do you perform the procedure?

First you must fix the specimen to be examined (from a clinical source or from an agar plate) to the microscope slide either by heating the slide or by the use of methanol.

After the specimen is fixed, flood the slide with the primary stain, crystal violet (purple). Here the bacterial cells are filled with stain. Rinse the slide with water.

Next flood the slide with Gram’s iodine. A crystal violet/iodine complex is formed in the cell. Rinse the slide.

Wash the slide with an organic solvent (acetone-alcohol) decolorizer and finally stain with a counterstain, safranin (red).

How come some bacteria stain gram positive and others gram negative?

This is due to different cell wall composition with the two bacterial groups. A gram positive organism, e.g. Staphylococcus aureus will retain the crystal violet because of a thick peptidoglycan layer and teichoic acid cross-links (cells appear purple microscopically).

Gram negative bacteria, e.g. E.coli lack this cell wall and the crystal violet/iodine complex is leeched out of the bacterial cell during decolorization. The acetone-alcohol disrupts the outer membrane of the gram negative cell causing the decolorization. After decolorization of gram negative bacteria, the cells become colorless and are subsequently filled with safranin (red) giving it the gram negative appearance microscopically (pink-red).

A Gram stained smear is examined using the oil immersion objective (1000x). Not only do you report the Gram reaction (positive or negative) but also the bacterial morphology (cocci or bacilli) and any formations (clusters or chains for example).

How is the Gram stain useful with clinical samples?

Often times treatment decisions can be made based on the Gram stain result alone. One example is in a critical culture site like blood or CSF where time is of the essence, a gram stain of gram positive cocci in clusters can let the treating physician know the he/she is dealing with a staphylococcus species and an appropriate antibiotic for staph can be started while waiting for the culture result.

The Gram stain is one of the most important laboratory procedures in the clinical microbiology laboratory and may appear to be deceptively simple. Instead, a technologist who is very proficient at reading Gram stained smears typically has considerable experience and training.

Monday, September 13, 2010

Today is "Chlamydia Monday" in Sweden

In an effort to increase awareness of the sexually transmitted infection and to promote the Chlamydia free testing offered, the Swedish Institute for Infectious Disease Control (Smittskyddsinstitutet) has declared Monday, September 13, 2010 as Chlamydia Monday.

This initiative by the Swedish Institute for Infectious Disease Control come after the institute became responsible for combating sexually transmitted infections (STI) this past July.

In Sweden, four people per hour contract Chlamydia though according to statistics the numbers are dropping.

In the US, Chlamydia is the most commonly reported bacterial STI, approximately 3 times more reported than gonorrhea.

Chlamydia trachomatis, specifically types D through K are responsible for sexually acquired genital infections in adults and perinatally transmitted infections in newborns and infants. Chlamydia can be transmitted during oral, vaginal and anal sexual contact with an infected partner.

Sometimes Chlamydia is called the “silent disease” because so many people have it and don’t know it. Asymptomatic infection in men is as high as 25%, in women 70%! If symptoms do appear, it’s usually within 1-3 weeks.

When symptoms are present in men it’s sometimes difficult to distinguish from gonorrhea; urethral discharge, itching and burning during urination. In women, symptoms are also similar to gonorrhea with discharge and bleeding being most common.

Men or women who have receptive anal intercourse may acquire chlamydial infection in the rectum, which can cause rectal pain, discharge, or bleeding. Chlamydia can also be found in the throats of women and men having oral sex with an infected partner.

Pelvic inflammatory disease (PID) and epidyimitis, in women and men respectively, are the most common complications with untreated chlamydia.

Rarer complications include: Bartholinitis, proctitis and Fitz-Hugh-Curtis syndrome.

Tests are available for the detection of Chlamydia that use genital or urine samples. Chlamydia can be treated with the antibiotics Doxycycline (twice daily for 7 days) or Azithromycin in a single dose. Erythromycin is the drug of choice for infants and Azithromycin for pregnant women.

It is common practice to treat for gonorrhea also when diagnosed with chlamydia. Co-infections are relatively common.

Saturday, September 11, 2010

Cockroach brains to fight "superbugs"?

It’s not a typo, the title is correct, at least according to researchers at the University of Nottingham’s School of Veterinary Medicine.

Those filthy, disgusting creatures appear to have some antibacterial properties in their brain that could be a new source of life-saving antibiotics in the future.

The researchers found that the tissues of the brain and nervous system of cockroaches and locusts were able to kill more than 90 per cent of MRSA and pathogenic, drug-resistant Escherichia coli, without harming human cells.

This discovery seems to come when “superbugs” like multi-drug resistant bacteria like Acinetobacter, Pseudomonas and others are being seen with increasing frequency.

Simon Lee, a post-graduate researcher stated, “We hope that these molecules could eventually be developed into treatments for E. coli and MRSA infections that are increasingly resistant to current drugs. These new antibiotics could potentially provide alternatives to currently available drugs that may be effective but have serious and unwanted side effects.”

He goes on to say that it shouldn’t be surprising that creatures like the cockroach secrete antimicrobials, “Insects often live in unsanitary and unhygienic environments where they encounter many different types of bacteria. It is therefore logical that they have developed ways of protecting themselves against micro-organisms.”

Hundreds of Pakistani flood victims fall ill after eating rice: Bacillus cereus food poisoning?

In a report out of the Daily Times in Pakistan, more than 250 flood victims at a relief camp at Ibrahim Hyderi fell ill immediately after eating cooked rice provided to the relief camp.

The people sickened immediately started vomiting and at least 59 victims had to be hospitalized because their symptoms were so severe.

Cooked food was provided to the relief camp by a local philanthropist, which included rice. An officer in the Karachi government stated that by the time the food arrived at the camp, the rice had turned stale.

But since the rice was not rotting it was served to the flood victims. Almost immediately after ingesting the rice, victims started vomiting and a majority of the victims fell unconscious.

A foodborne illness associated with rice that has not been properly stored suggests that this outbreak is related to Bacillus cereus.

Bacillus cereus is an aerobic, spore-forming bacterium found in the soil and the environment worldwide. It commonly found in low levels in raw, dried and processed foods.

A well recognized and common cause of food poisoning worldwide, Bacillus cereus causes two types of toxins: a diarrheal type and a vomiting type.

The diarrheal type of this food poisoning is usually associated with meats, milk and vegetables. The onset for the disease is from 8-16 hours and it lasts 12 to 14 hours.

The vomiting type of this food poisoning is due to rice, grains, cereals and other starchy foods. The onset is quite rapid (30 minutes to 6 hours) and usually lasts a day or so. This type is frequently associated with outbreaks due to cooked rice held at room temperature.

This type of food poisoning is rarely fatal and cannot be transmitted from person to person.

Improper storage of food stuffs is the issue. Bacillus cereus spores can survive boiling and if the food, rice for example is stored at ambient temperature, the spores can germinate into toxin producing bacteria.

Then the person eats the rice contaminated with the pre-formed toxin that causes the illness.

The vomiting type of toxin is also heat resistant, much like the enterotoxin that causes Staphylococcus aureus food poisoning, and cooking will not destroy the toxin.

Wednesday, September 8, 2010

Loa loa: the African eye worm

This filarial parasite is indigenous to Central and Western Africa especially in rain forest areas. In the Congo River basin, it is estimated that up to 90 per cent of inhabitants in some villages are infected with the parasite.

Loa loa is transmitted to people through the bite of a deer fly of the genus Chrysops. The fly ingests microfilariae from the blood of an infected host and develops into the infective stage within 12 days. Here they migrate to the proboscis of the fly and are transmitted to another person through a bite.

Chrysops species feed only during the daytime and the bite is quite painful. Primates can be a reservoir host.

The symptoms of loasis usually don’t appear for years after getting infected but have occurred as early as several months. The microfilariae (larvae) typically appear in the peripheral blood within 6 months.

The adult worms may grow up to 70 mm and can live in the host for 17 years, all the time producing microfilariae.

This chronic disease in humans is characterized by the migration of the adult worm through the subcutaneous and deeper tissues. During this continuous migration, it can produce transient, painless calabar swellings which can grow to several centimeters in diameter. It has been suggested that the calabar swellings are a reaction to worm metabolites.

Worms can pass in front of the eyeball  or across the bridge of the nose causing pain, swelling and anxiety.

Diagnosis of Loa loa can be based on the presence of calabar swellings, worms passing the eyes, eosinophilia or identification of microfilariae in day blood.

Treatment can include diethylcarbamazine (DEC), ivermectin and surgical removal of the worm from the conjunctiva when feasible. The use of steroids and antihistamines may also be required.

Prevention is by preventing fly bite by repellents, screen houses and protective clothing. If you are a visitor to an endemic area where risk is high, a weekly dose of DEC is prophylactic.

Tuesday, September 7, 2010

Guinea worm disease down over 99% since late 1980s

To say the progress made has been “remarkable” is really putting it mildly. This parasitic disease, guinea worm disease, had plagued the continent of Africa to the tune of 3.5 million people just 24 years ago.

According to the Carter Center’s latest numbers the number of cases of dracunculiasis was a mere 3190 in 2009.

Certain countries showed great progress toward eradication, for example, Ghana had over 4000 cases in 2006, the first half of this year there were only 8.

Nigeria, which once had the greatest amount of cases (653,000 in 1988) had completely eliminated the parasite last year.

Several factors have led to this dramatic success; better funding, free treatment, better compliance by villagers and an improved water supply.

Villagers volunteering to improve their condition was another huge factor. Things like health education, cloth filters, and advocating for safe water were all a result of volunteers working to a common goal.

While most countries are on the doorstep of eradication, Sudan is the one country where there were a significant amount of cases. Of the 3120 cases in all Africa, 86% or 2733 cases were from Sudan.

So what is Guinea worm disease?

This is a parasitic disease of subcutaneous and deeper tissue. It is caused by the roundworm, Dracunculus medinensis.

Most countries where this disease is endemic are in Africa; Ghana, Mali, Niger, and Sudan. It has been eradicated from 20 formerly endemic countries through a vigorous eradication program.

How do people get this parasite?

The adult female worm in an infected person migrates to the skin’s surface and a blister is produced. Upon contact with water, the blister ruptures and the adult releases larvae into the water.

In the stagnant fresh water the larvae are ingested by copepods (a tiny crustacean). People later swallow the infected copepods from drinking water from infected step wells, ponds and other surface water.

From here the larvae migrates and penetrate the stomach and intestinal wall then they mature into adults. The female mates and grows to full maturity and subsequently migrates to the subcutaneous tissues (frequently the legs and feet) and the cycle continues.

The adults can grow up to one meter in length. The emerging worm is removed by rolling it on a stick a few centimeters each day.

Symptoms typically include burning and itching of the skin in the area of the lesion, and frequently fever, nausea, vomiting, hives accompany the blister formation.

Some of the more serious problems of guinea worm disease are after the blister ruptures, secondary bacterial infections can occur. Tetanus infections can also happen at the site of the lesion.

After a person gets infected with Dracunculus it takes about a year for disease to occur.Because there is no acquired immunity to the infection, people can get reinfected repeatedly.

So what methods are being used to eradicate this disease?

Most importantly is education. Teaching the population that guinea worm infection comes from drinking unsafe water, people with blisters should not enter any source of drinking water and drinking water should be filtered through fine mesh cloth to remove copepods.

In addition, abolish things like step wells and construct where possible protected wells for potable water. They also use the larvacide, temephos in ponds, reservoirs and step well to control copepod populations. High risk populations in endemic areas should be immunized against tetanus.

It’s been 30 years since smallpox was eradicated from humankind, guinea worm disease could be the next disease to join the list.

Monday, September 6, 2010

Thailand's Surin province plagued with dengue fever

Dengue fever, the mosquito-borne viral disease is spreading across Thailand and has infected at least 2300 in the Surin province alone.

The disease has been seen in at least 17 districts which to date has resulted in one death according to Thai health officials. Most of those infected are young children and teens ages 5 to 14.

Dengue fever is an infectious disease carried by mosquitoes and caused by any of four related dengue viruses. This disease used to be called “break-bone fever” because it sometimes causes severe joint and muscle pain that feels like bones are breaking.

Dengue fever of multiple types is found in most countries of the tropics and subtropics particularly during and after rainy season.

There are four types of dengue virus: DEN-1, DEN-2, DEN-3 and DEN-4.

People get the dengue virus from the bite of an infected Aedes mosquito. It is not contagious from person to person.

There are three types of dengue fever in order of less severe to most: the typical uncomplicated dengue fever, dengue hemorrhagic fever (DHS) and dengue shock syndrome (DSS).

The symptoms of classic dengue usually start within a week after being infected. They include very high fever, up to 105°F, severe headache, pain behind the eye, severe joint and muscle pain, nausea and vomiting and a rash.

Symptoms of DHF include all the symptoms of classic dengue plus severe damage to the blood vessels. Bleeding from the nose, gums or under the skin are common. This form of dengue can be fatal.

Symptoms of DSS include all of the above symptoms plus; fluid leaking outside of blood vessels, massive bleeding and shock. This form of the disease usually happens in children experiencing their second infection.

Two-third of all fatalities occurs among children.

There is no treatment for dengue, just treat the symptoms. Persons who think they have dengue should use analgesics (pain relievers) with acetaminophen and avoid those containing aspirin. They should also rest, drink plenty of fluids, and consult a physician.

The best preventive measure for residents living in areas infested with Aedes mosquito is to eliminate the places where the mosquito lays her eggs, primarily artificial containers that hold water.

Sunday, September 5, 2010

India: Mother attempts to kill daughter because she had leprosy

A woman has been booked for attempting to murder her 17 year old daughter in the woods on Nellore district.

Parveen Bee, the mother of three and relative Mahabub Peera allegedly took the girl from her home to the Porumamilla forests explaining they were taking her for treatment. Instead the alleged murder plot resulted in the girl being strangled with her own chunni and subsequently stoned resulting in injuries to the head and eyes.

The girl was presumed to be dead and the alleged murderers left, however to their surprise the girl regained consciousness and struggled to get to a road where travelers on the road found her and took her to authorities and the hospital.

What did this 17 year old girl do to deserve this, from her own mother no less? Allegedly the mother wanted her dead because the girl, who was afflicted with leprosy, had become an obstacle for marriage proposals for her other children!

Saturday, September 4, 2010

Tokyo-area hospital battling multi-drug resistant bacteria and legal issues

Nearly four dozen patients at Teikyo University Hospital in Tokyo has been infected with an extremely resistant bacteria known as Acinetobacter since last August.

Of the 46 patients infected with Acinetobacter, 27 patients have died with 9 deaths being directly attributed to the infection.

The nine patients who died as a result of the Acinetobacter infection, both men and women ages 53 to 89, had an immunodeficiency or other underlying condition like leukemia and kidney disease.

Of the 18 other deaths, 12 were unrelated to the infection while 6 are still being investigated.

And now the criticism has begun concerning this hospital’s infection control issues and the resulting deaths which began last year because they were not reported to health authorities until last Thursday.

And now the hospital and individual doctors are being questioned by the Metropolitan Police Department (MPD). The investigation will try to determine whether the facility properly handled such matters as disinfecting the hospital and treating infected patients.

The MPD will investigate whether it is possible to prosecute for personal negligence resulting in injury.

To make matters worse, another “superbug” has emerged in the hospital. At least three patients at the hospital have been reportedly infected with an multi-drug resistant Pseudomonas aeruginosa bacterium.

One patient who suffered from heart disease has died due to a blood infection with the bacteria.

What is Acinetobacter?

Acinetobacter species in general are found in soil and water. The bacterium in the hospital environment can thrive in wet or on dry surfaces. It is typically transmitted in the hospital environment by not following the strictest infection control practices.

Acinetobacter is classified as an opportunistic pathogen. Healthy people can carry the bacteria on their skin with no ill effects, also known as colonization.

But in newborns, the elderly, burn victims, patients with depressed immune systems, and those on ventilators, Acinetobacter infections can be fatal.

Friday, September 3, 2010

Goodbye smallpox, hello...monkeypox?

At least as far as the Democratic Republic of the Congo is concerned. This according to researchers led by Anne Rimoin of the UCLA School of Public Health in a study published in the Proceedings of the National Academy of Sciences.

Since the last doses of smallpox vaccine were given in 1980 and smallpox was officially eradicated, cases of monkeypox have increased 20-fold according to the study.

Much of this is likely due to the immunity that smallpox vaccine granted to related viruses like monkeypox. Most of the patients infected with monkeypox were born after the discontinuation of smallpox.

Unlike smallpox which is strictly a human disease, monkeypox not only spreads from animal to animal but also from animals to humans.

In areas like the Congo where monkeys and squirrels are everywhere and more and more people have contact with them; the spread of the virus to humans becomes more likely. This makes control of the disease difficult just as most zoonotic diseases are.

What does this mean in the United States? Monkeypox did rear its ugly head here in 2003 when dozens of people became ill. The virus arrived courtesy of imported African rodents who were infected which eventually spread among the prairie dog population in the Midwest. Some fear that US travelers could import the disease and establish the virus in the rodent population.