Infectious Disease Blog

Scientists drafted the first map of emerging infectious disease hot spots in the world, according to a study published last week in the journal Nature.

Unfortunately, the hot spots, designated in red, tend to have the least resources for infectious disease prevention.

Researchers from the U.S. and Britain assembled a database of 335 infectious diseases marked as a threat between 1940 and 2004. They then compared the frequency of unique outbreaks with possible environmental factors, such as population density and growth, geographic latitude and diversity of wildlife.

MedicineNet.com gives the following definition of an emerging infectious disease:

Emerging infectious disease: An infectious disease that has newly appeared in a population or that has been known for some time but is rapidly increasing in incidence or geographic range.

Examples of emerging infectious diseases include:

• Ebola virus (first outbreaks in 1976 and the discovery of the virus in 1977),

• HIV/AIDS (virus first isolated in 1983),

• Hepatitis C (first identified in 1989, now known to be the most common cause of post-transfusion hepatitis worldwide),

• Influenza A(H5N1) virus (well known pathogen in birds but first isolated from humans in 1997),

• Legionella pneumophila (first outbreak in 1976 as Legionnaire disease and since associated with similar outbreaks linked to poorly maintained air conditioning systems),

• E. coli O157:H7 (first detected in 1982, often transmitted through contaminated food, has caused outbreaks of hemolytic uremic syndrome), and

• Borrelia burgdorferi (first detected in 1982 and identified as the cause of Lyme disease).

According to Popular Science, the researchers discovered:

In the end, they discovered that emerging infections in developing nations tended to be novel pathogens, encountered as humans squeeze further into previously uninhabited regions and have more contact with the wildlife found there. Conversely, the emerging infections in the developed world were primarily drug-resistant pathogens, bred by widespread antibiotic use in the human and livestock populations.

An infectious disease expert discussed the possible implications of the study with Scientific American:

This study and others before it increasingly show “that there are patterns which can be used for the forecasting of novel pandemics,” says infectious disease specialist Nathan Wolfe of the University of California, Los Angeles, who was not part of the study. “It helps to inform the kind of monitoring that’ll have to be in place to take this to the next step, to really prevent the next pandemic.”

To read the abstract in Nature, click here.

To many, tuberculosis is a dead disease.

To be safe though, just about everyone in the U.S. gets tested for tuberculosis, or TB. Few of us really believe that we will get the disease.

But, in Toronto, Canada, there’s a growing chance of a tuberculosis outbreak. The current system would not be ready to handle an outbreak because it lacks a centralized system of TB clinics, according to United Press International. Ontario is the only Canadian province without a centralized TB system.

Toronto’s growing immigrant population is the reason some experts say there may be an increase in cases of deadly, contagious tuberculosis, according to the Toronto Star.

About one-fourth of Canada’s TB cases originate in Toronto, according to the Star. Of the 1,600 active cases of TB in Canada, 400 come from Toronto. Experts say that any country where TB is epidemic should expect to see a higher incidence of the disease as immigration rates rise in the country.

According to the article, Toronto will face tuberculosis problems as long as the city is an immigration center:

“It seemed like infectious diseases would disappear from the planet,” says Dr. Elizabeth Rea, an associate medical officer of health for Toronto Public Health’s TB prevention and control program. “They haven’t. Particularly for Toronto. Our rates are driven by what is happening outside the city … TB is not going to disappear from Toronto as long as we are an immigration centre. We need to plan for cases to continue to arrive here and to be able to deal with them at the highest level of care.”

Canada Immigration Blog writer Sergio R. Karas, a lawyer and certified specialist in Canadian citizenship and immigration, gave insight on allowing immigrants with TB into Canada:

I fail to see why potential immigrants with active TB should be admitted to Canada. Public safety demands that they should not be admitted. In my view, it is a “no-brainer”.

I was reading a book entitled “The Chicago ‘L’” when I stumbled upon a photo of a “fresh air car” from 1915. Chicago was doing its best to stave off an influenza outbreak, so the “L” would run one car with most of its windows opened to maximize air circulation. At the time, many people believed that fresh air from the lakefront would promote good health. The open-air car would only run on certain trains between Jackson Park and north suburban Evanston.

Advertisements inside the car read:

“Too much fresh air is just enough.”

“Get the fresh air habit; dress warm enough to enjoy it.”

“The Chicago ‘L’” by Greg Borzo details the history of the “L” with photographs. Check out the book on Amazon.

The Chicago History Museum houses the first passenger car to operate on the “L” back in 1892. The museum also gives four different “L” tours of the city on Sundays: Brown Line, Green Line south, Green Line west and Blue Line.

Today and on March 30, Greg Borzo, the author of the aforementioned book, will lead a tour of the Loop “L.” Information and tickets are available at the Chicago History Museum by clicking here.

San Diego County officials reported Friday that five more children have come down with measles, bringing the total number of cases to 11, according to San Diego TV station FOX 6.

Five of the cases are thought to be linked to an 8-year-old who may have got measles at a San Diego charter school. Three other cases may be connected to an infant who may have contracted the disease at a La Jolla children’s clinic.

According to the San Diego Union-Tribune,

All of the 11 confirmed patients, from 10 months to 9 years old, were not vaccinated either because they were younger than 1 – the minimum age for measles inoculation – or because their parents objected to having them vaccinated, county officials said.

The FOX 6 story includes links to three video interviews with Dr. Richard Halverson, all posted on YouTube. He covers the danger of measles, if the disease can be good for you and how it can be a killer disease in underdeveloped countries.

Thousands blockaded a highway near the capital of Paraguay this week, demanding vaccinations for yellow fever after the disease’s first appearance in the country after more than 30 years.

There were five confirmed cases of yellow fever in Paraguay this week, but there have been no deaths reported, according to MSNBC.

Following the outbreak, Brazil flew more and 50,000 doses of yellow fever vaccine to Paraguay, reported the Guardian. Also, Peru has promised to send 250,000 doses of the vaccine next week.

Yellow fever is transmitted to humans by infected mosquitoes. According to the CDC, there are two stages of symptoms: initial and toxic.

Initial phase symptoms include:

• Fever and chills
• Severe headache
• Back pain
• Aches
• Nausea
• Fatigue
• Weakness

The toxic phase begins when the fever returns. Toxic phase symptoms include:

• High fever
• Nausea and vomiting
• Headache
• Back pain
• Abdominal pain
• Fatigue
• Jaundice

The influenza pandemic of 1918 rocked the United States as it swept the country in three lethal waves. Hospitals were overwhelmed with patients and there was little doctors could do because of a lack of the proper drugs and vaccines.

Despite medical advances, there’s still a dose of uncertainty about the U.S.’s capacity to respond to an infectious disease emergency. This documentary suggests that we may be at more of a disadvantage now than the people who lived through the 1918 influenza pandemic.

The video was produced and underwritten by the Johns Hopkins Center for Civilian Biodefense Studies along with the U.S. Department of Health and Human Services.

What happens when not just one, but two outbreaks of infectious diseases strike a country? The people of Malta are in the midst of it.

After outbreaks of rubella and scarlet fever were confirmed in Malta this week, the country’s Health Promotion and Disease Prevention Department has told the public there is no reason to be alarmed.

What struck me about these outbreaks is that neither of these diseases is common in Malta. One expert even went as far to call them rare illnesses in Malta. How does an illness rarely found in a part of the world turn up there?

Searching a bit, I also found that there were four confirmed cases of rubella this month in Sydney, Australia.

In this day and age, rubella has become somewhat or a rarity, with most infants receiving the measles, mumps and rubella (MMR) vaccine. Children receive the first shot around the age of one and a booster dose at the age of 4 or 5. In the Australian cases, all four children were infants. Perhaps they had not yet received their MMR vaccines, which would explain their susceptibility to the disease. However, the three people who got rubella in Malta were in their 20s. It was confirmed that none of these three patients had the MMR vaccine.

Following up to my post on low immunization rates in American adults, maybe the U.S.’s National Foundation for Infectious Diseases has a point. Not enough people are getting vaccines. This problem spreads beyond the U.S. and to other countries in the world, such as Malta. Do I hear a global call for vaccination at hand?

A device made to help the environment is likely to be the cause of an outbreak of Legionnaires’ disease in Norway. Industrial air scrubbers, which are air pollution control devices that remove particulates and gases from exhaust streams, may have spread the disease to 56 people.

This is an example of an industrial air scrubber made by Monroe Environmental. Please note that the make and model of the air scrubber were not mentioned in the article. 

Legionnaires’ disease is a form of pneumonia caused by the bacterium Legionella. According to MedlinePlus:  

Legionnaires’ disease is a type of pneumonia caused by bacteria. You usually get it by breathing in mist from water that contains the bacteria. The mist may come from hot tubs, showers or air-conditioning units for large buildings. The bacteria don’t spread from person to person.

Out of the 56 people that were diagnosed with Legionnaires’ in May 2005, 10 of them died. Investigators found matching strains of bacteria in the air scrubbers and the infected patients.

This isn’t the first time the threat of Legionnaires’ has arisen from an air conduit. Less than a month ago in Auckland, New Zealand, high counts of Legionella were found in cooling towers in neighboring buildings. Legionnaires’ was also to blame for three deaths in Christchurch and one in Beachlands, New Zealand, in 2005.