infectious disease


A Surprising New View Of Flu: Rethinking The 1918 Pandemic

Giving treatment to influenza patient at the U.S. Naval Hospital. New Orleans, Louisiana, Circa 1918. (Navy Medicine/Flickr)

Giving treatment to influenza patient at the U.S. Naval Hospital. New
Orleans, Louisiana, Circa 1918. (Navy Medicine/Flickr)

By Richard Knox
Guest Contributor

Ever since 1918, the world has wondered why a novel flu virus touched off an explosive pandemic that killed as many as 50 million people – most of them healthy young adults — and whether it could happen again.

Flu researchers today report some surprising news: They say the 1918 virus was no super-bug. Instead, its deadliness had to do with how very different it was from the flu viruses circulating 25 or 30 years before, when the young adults of 1918 were first exposed to the flu.

Indeed, the new study says it’s that first childhood exposure that determines how people will fight off – or fall prey to – every other flu virus they will encounter in a lifetime.

That’s a very different way of looking at flu, both pandemics and regular seasonal outbreaks.

Much of the current emphasis is on the virus itself. Scientists around the world are doing controversial “gain-of-function” experiments – adding and subtracting pieces of genes from flu strains to see what mutations make some viruses so virulent.

Instead of focusing on flu virus itself, authors of a paper published Monday in the Proceedings of the National Academy of Sciences say scientists and public health experts should pay attention to the vulnerabilities of different age groups to any new flu virus – and how those immune gaps might be filled in by targeted vaccine strategies.

“Childhood exposure seems to give kick-ass immunity to that kind of flu virus for many, many decades,” says evolutionary biologist Michael Worobey of the University of Arizona, the paper’s lead author. Continue reading

Flu Or Just Crud? Latest Wrinkle In Flu Tracking: Home Tests

The rapid home flu test distributed by GoViral (Courtesy GoViral)"

The rapid home flu test distributed by GoViral (Courtesy GoViral)

You’re aching, you’re shivering, you’re coughing. You’re definitely, miserably sick, but is this real, potentially serious flu or just some garden-variety winter crud?

Better find out. You pull your handy-dandy virus test kit from the shelf, insert the nasal swab gently into your nostril and twist it around three times to coat it with your (copious) mucus. You swish the swab in liquid and deposit drops of your germy mix on the four wells of the instant test. Ten minutes later — voila. Sure enough, you test positive for an influenza type A. You call your doctor to ask about anti-viral meds, and — as a good citizen of your disease-tracking community – you go online to report your diagnosis to Flu Near You. On its map, you see that you’re not alone: a dozen of your neighbors have the same bug.

Futuristic? Not if you live in the Boston area and are part of a new flu-tracking experiment funded by the National Science Foundation, called GoViral. Run by researchers at Boston Children’s Hospital, the three-year project is just getting under way now, as this year’s flu season takes on steam.

Flu is more than a nuisance. It’s a serious threat — infecting tens of millions of Americans a year and killing an average of 24,000 — and public health types try hard to track and understand it. The CDC monitors reports from doctors’ offices, including lab test results. Google Flu Trends watches online searches for telltale symptoms. Flu Near You, where GoViral is based, already brings together thousands of volunteer sentinels who report online when they have symptoms. Now, GoViral will take testing into the home, where many flu patients hole up rather than seeing the doctor.

“It’s never been done before, to give a lot of people in their homes these tests,” said Dr. Rumi Chunara, GoViral’s lead researcher. “This is the first time that we’re actually crowdsourcing diagnostic samples from people.”

The project breaks new ground in flu tracking, said Dr. Lyn Finelli, who leads flu surveillance and response at the National Center for Immunization and Respiratory Diseases at the CDC: “This is the first time that I know of that anybody has used what we call participatory surveillance,” she said, “where people indicate whether they’re well or ill, and participate in home testing and send the tests in. This is a very novel look at a surveillance system and home testing.”

Dr. Chunara plans to distribute several hundred free flu test kits to Boston-area members of the public who sign up (here) this winter, and expand to encompass more areas next year. The kits include the rapid test, which can only check for four common viruses but gives an instant answer, and also a saliva test that must be sent in to a laboratory and can reliably detect 20 common viruses (though you may be better by the time you get the result.) Continue reading

On New Bird Flu, From A Doctor Who’s Been There: We Need Time

A worker at Sanofi Pasteur, the world’s larges influenza vaccine manufacturer. Some researchers in the United States have published letters in the journals Nature and Science arguing to create a more virulent strain of the H7N9 avian flu to prepare for its possible spread in humans.  (Sanofi Pasteur/Flickr)

A worker at Sanofi Pasteur, the world’s larges influenza vaccine manufacturer. Some researchers in the United States have published letters in the journals Nature and Science arguing to create a more virulent strain of the H7N9 avian flu to prepare for its possible spread in humans. (Sanofi Pasteur/Flickr)

We wrote earlier this week about the latest avian flu news, concerning a new strain called H7N9 that has killed at least 43 people in Asia. Summary: A probable case of human-to-human transmission has been reported in China, and some flu researchers say they’re going to alter the H7N9 virus in the lab in ways that will make it more dangerous, in order to understand and defend against it better.

I was left a little confused about those highly controversial plans to modify the virus. Very scary. What if it got out? On the other hand, bird flu is scary too. Shouldn’t we do all we can to fight it?

I spoke with Dr. Michael V. Callahan, a Massachusetts General Hospital infectious disease and disaster medicine physician who deploys to large-scale disease outbreaks. He’s the director of a Department of Defense-funded project to predict and defend against dangerous virus mutations. He is also an expert on flu outbreaks and one of the few Americans to have treated H7N9 patients last March in China.

How, I asked, does he see the letters in Science and Nature announcing the researchers’ plans to modify the H7N9 virus?

Dr. Michael V. Callahan outside Harvard Medical School (Photo: Joseph Ferraro, Massachusetts General Hospital)

Dr. Michael V. Callahan at Mass. General Hospital (Photo: Joseph Ferraro, MGH)

“In the right environment, with peer review, these gains of function studies are revealing and will help us home in on those conserved, critical elements of influenza that we might someday be able to use to block [all strains of flu] with one vaccine,” he said.

So how about the suggestion in the letter that the research should begin quickly in hopes of producing something of value by this winter?

“Both unwise and impossible,” he answered. “DARPA [The Defense Advanced Research Projects Agency] has developed the world’s fastest pathogen-to-vaccine capability, capable of 100 million doses in three months. This is the only process that could deliver vaccine by November, the start of flu season.”

“Unfortunately, the vaccine capability is not fully approved by the FDA. The traditional cell and egg based vaccine systems require months to develop a ‘production strain,’ a hybrid of H7N9 and a ‘tame’ strain, which can be placed in cells and eggs. Continue reading

Déja-Vu On Avian Flu: Probable Human-Human Spread, Research Debate

A worker at Sanofi Pasteur, the world’s larges influenza vaccine manufacturer. Some researchers in the United States have published letters in the journals Nature and Science arguing to create a more virulent strain of the H7N9 avian flu to prepare for its possible spread in humans.  (Sanofi Pasteur/Flickr)

A worker at Sanofi Pasteur, the world’s larges influenza vaccine manufacturer. Some researchers in the United States have published letters in the journals Nature and Science arguing to create a more virulent strain of the H7N9 avian flu to prepare for its possible spread in humans. (Sanofi Pasteur/Flickr)

This is not my favorite topic, potential bird flu pandemics that could sweep humanity and kill hundreds of millions. But I also worry that a “cry wolf” phenomenon will set in, and then we won’t be prepared when the Big One hits. So let’s just consider, for a moment, the latest anxiety-producing avian flu news, about a strain called H7N9 that has killed at least 43 people in China.

Today brings two news items on this new strain: The BMJ medical journal reports the first case of probable human-to-human spread of H7N9, from a Chinese father who caught it from poultry to his daughter. And avian flu researchers publish a public letter in the prestigious journals Nature and Science saying they must produce “super-strains” of H7N9 — more easily transmitted, more resistant to attack — in order to understand the virus better and prepare to defend against it. (Science reports on some initial responses to the letter: Critics skeptical as flu scientists argue for controversial H7N9 studies.)

Science also offers this helpful round-up of the background, the reason why this all feels like flu déja vu. It’s that this is familiar ground from the last avian flu scare, with the virus H5N1: Continue reading

Worry About New ‘World Threat’ Virus? Specialist: We Just Don’t Know

You may have seen this headline last week: “World Health Organization says new virus may be ‘threat to entire world.‘” And if you’re like me, you may have been surprised by your own ho-hum reaction. Is this a crying-wolf situation? Have we been warned about too many potentially scary viruses over the last few years? Or are we just getting more used to living with viral uncertainty? Here, Dr. Paul Sax, clinical director of the Division of Infectious Diseases at Brigham and Women’s Hospital, writes about his own reaction to this latest outbreak in the face of insufficient information.

By Dr. Paul E. Sax
Guest contributor

From one of my close friends — a non-MD — comes this alarming video.

And here’s his email:

Concerned? Terrified? I bet your department is buzzing about this.

Um, not quite — especially since, among the 49 cases in the world (apparently there are five more than the WHO reported), exactly zero have occurred thus far in the United States. As of May 29, 2013, it hasn’t even cracked the front page of the CDC site.

Is MERS-CoV — short for Middle East Respiratory Syndrome Coronavirus – potentially of great concern? Of course. The WHO response seems right, especially with the parallels to SARS.

Coronoviruses (these are not the new Middle East virus) are a group of viruses that have a halo, or crown-like (corona) appearance when viewed under an electron microscope. (Wikimedia Commons)

Coronoviruses (this image is not of the new Middle East virus) are a group of viruses that have a halo, or crown-like (corona) appearance when viewed under an electron microscope. (Wikimedia Commons)

But do we garden-variety infectious disease specialists know how serious it will be on a global basis? Of course not. As with the first SARS cases, the first anthrax cases, the first West Nile cases, the first hantavirus cases, even the first AIDS cases — we really don’t have enough points on the graph yet to make any sort of confident predictions.

And from a practical perspective, the clinical unfamiliarity doesn’t help. If someone walked into our emergency room tomorrow with fever, cough, and respiratory symptoms, would we know how to distinguish MERS-CoV — from the hundreds (OK, thousands) of other causes of similar illnesses?

Initially, not a chance. The denominator of people with these complaints is just too gargantuan. It will probably take someone with a particularly severe respiratory illness, along with the appropriate exposure (“He just returned from a 10-day business trip to Riyadh”) for an astute clinician to make the connection.

So how should we infectious disease doctors, who are supposed to know everything, respond to these emails in the interim? Continue reading

Boston Biolab Clears State Hurdle For Max-Security Work

The National Emerging Infectious Diseases Laboratories, on the BU Medical Campus. Photo by Kalman Zabarsky, courtesy of BU)

The National Emerging Infectious Diseases Laboratories, on the BU Medical Campus. Photo by Kalman Zabarsky, courtesy of BU)

It’s widely referred to as the “needle” — as in NEIDL, the acronym for the National Emerging Infectious Disease Laboratory. It’s a futuristic, seven-story tower near Boston Medical Center in the South End, built to house high-level infectious-disease labs. And its fate has been mired in controversy for years, the kind of struggle you’d expect around a plan to research some of the world’s deadliest pathogens right near a densely populated neighborhood.

BU Today explains: “Construction on the $200 million facility was completed in September 2008, but controversy and litigation have kept much of the building’s 192,000 square feet of laboratory space closed.”

Now, BU Today reports that the NEIDL has just gained a key approval:

The Massachusetts Secretary of Energy and Environmental Affairs has given approval for the lab to conduct research at Biosafety Level 3 (BSL-3) and Biosafety Level 4 (BSL-4). The state agency issued a Massachusetts Environmental Policy Act (MEPA) certificate on Friday, clearing the way for the issuance of final state permits for the project.”

Some background:

As the Globe’s Stepehen Smith wrote in 2010: “South End and Roxbury residents have taken to the streets and the courts to protest the project. While state and federal judges allowed construction on the $200 million project to continue to completion — it includes both a high-security Biosafety Level-4 lab, as well as other research facilities — they mandated further safety reviews before it could open for research.”

WBUR’s Delores Handy took a press tour of the building last year, and officials told her that the NEIDL was probably the safest building in the city, and that the fence around it could stop truck bombs.

NECN’s Peter Howe described “foot-thick reinforced concrete walls, triple microscopic air filtration systems, intensely guarded entrances and exits, doors controlled by iris scanners to allow only authorized scientists and security personnel in to specific floors, and hundreds of surveillance cameras to prevent anyone from trying to sneak deadly biological samples out of the building to create terrorist weapons.”

Critics point out that the building is just off the Southeast Expressway in the densely populated South End. This, they say, is an issue of environmental justice.

But Boston Mayor Thomas Menino told reporters on the tour: “This is about the future. It’s about making sure that we have the tools in our city to do the research and the findings that we need to cure some of these diseases out there.” Continue reading

Could Climate Change Affect Flu?

flu shot

For filing in the folder labeled “Hmmmm,” as in “Interesting theory. Let’s see.”

In a helpful Q&A on this year’s flu season and flu in general, Mother Jones writes that one reason flu tends to spread in winter is that the virus is known to thrive in low humidity, a condition common in the winter cold. Mother Jones senior editor Kiera Butler has an “Aha” moment: “So that’s why the flu is so bad this year — the drought! So climate change actually made the flu worse, right?” But nothing is so simple…

Wouldn’t it be nice if epidemiology were that easy? Unfortunately, it’s not. If that were the case, you’d never see the flu in hot, humid places. But there’s just as much flu in Florida right now as there is in some parts of Canada. Other variables make it impossible to predict flu seasons based on weather alone.

It’s worth noting, though, that in a paper last year, [flu researcher Jeffrey] Shaman and his colleagues did document that each of the four flu pandemics of the 20th century were preceded by La Niña cycles, likely because birds mingled with each other differently during these unusual weather patterns. The flu strains that they were carrying probably hybridized and created a strain so new that humans had no immunity to it. Since, as we recently learned from this Climate Desk video, climate change does interact with El Niño/La Niña cycles, it’s not completely out of the question that global warming could affect flu transmission, at least indirectly.

Readers? Care to speculate?

Mass. General: ‘No Heroes!’ And Other Workplace Flu Protocol

Massachusetts General Hospital (Wikimedia Commons)

Massachusetts General Hospital (Wikimedia Commons)

No, we are not panicking, but yes, there’s a lot of flu about. Boston has just declared a flu-related health emergency, citing 700 confirmed cases thus far compared to 70 all last year.

In an alert to its staff, Massachusetts General Hospital reports that it’s seeing a flu season of “impressive intensity,” with an additional 40 to 80 patients with flu-like illness per day at the hospital’s health centers, outpatient clinics and emergency department.

“This has strained capacity to its limits. Likewise, many inpatient beds have been closed to isolate influenza patients, and hospital and practice staffing has been stressed by illness within their own ranks,” says the alert from Jeanette Ives Erickson, Mass. General’s senior vice president for patient care and chief nurse.

The memo lays out “best practices” for infection control that many a workplace may want to post and disseminate. To wit: (Slightly modified to remove some specifics, and still somewhat hospital-oriented)

• No Heroes! Staff with flu-like [illness] should leave the office and STAY HOME per the protocols of Occupational Health:
Do not come to work if you have a fever of 100.5°F or more and one or more of the following symptoms:
§ Runny nose or nasal congestion
§ Sore throat
§ Cough
§ Body aches
Continue reading

Doctor’s Dispatch: Three Unusual Aspects Of This Year’s Early Flu


The flu is hitting early and hard this year in Massachusetts and elsewhere.

We share the official data as it comes out. (See that rocketing red 2013 line in the CDC chart above.) But now for a fresh dispatch from the medical trenches — that is to say, in this case, the infectious diseases division of Mount Auburn Hospital. Dr. Robin Colgrove, a virologist by training, underscores that he’s passing along purely anecdotal reports — but they may provide early warning for both doctors and patients. We spoke today; his observations, lightly edited:

Clearly we’re seeing a lot more flu a lot earlier than we usually do. A few other things are unusual this year.

1. Despite the vaccine

It seems to us that we’re seeing more confirmed cases of influenza, using the rapid antigen test, in people who’ve been vaccinated than we would normally see. I was speaking about this at grand rounds the other day and among the primary care doctors in the audience, a number were saying the same thing.

Dr. Robin Colgrove

Dr. Robin Colgrove

Those cases have been mostly mild cases and it may be they have partial protection from the vaccine. (Flu vaccine efficacy has been controversial among researchers for quite some time. In ideal conditions with young healthy people, it may be 80-90 percent effective, but when epidemiologists look at the real world, the numbers have been much lower, maybe 50-60 percent efficacy.) Even in the best years, some people who get vaccinated also get influenza, but they are probably less likely to have severe and prolonged illness.

2. Atypical symptoms

A related point: There seem to be more people this year with atypical symptoms. Clinicians tend to be good at identifying flu: an abrupt high fever and severe malaise, and upper and lower respiratory symptoms. That pattern in the middle of a flu outbreak is almost always flu. Now we’re seeing people [who test positive for flu] with no high fever, maybe scratchy throats, possible gastro-intestinal symptoms. Continue reading

It’s Official: Flu Spikes Dramatically In Mass.


(Updated at 3:18)

I just checked the Massachusetts Department of Public Health weekly flu report, and the graph above made me say, “Yikes.” As in, all those anecdotes we’ve been hearing are not just anecdotes. This is really looking like an unusually early and heavy flu season in Massachusetts, and there are similar reports of early flu spikes from other states. (See our earlier post: Why Get A Flu Shot Now: Unusually Early Season, Already Here.)

As the DPH explains, the graph above measures reports of patients with “flu-like illness” — so they may have other viruses — from a network of “sentinel sites” believed to be representative of the population at large. The X axis represents weeks of the year, and the Y axis represents the percentage of patients seen at those practices who report flu-like symptoms. The DPH notes that the graph shows that flu-like illness “continued to increase and is much higher than what is typically seen at this time of year.”

But that dry public-health language does not capture the widespread misery of this nasty virus season. You may get a better sense of it in this excerpt of an email from a CommonHealth reader: “Just thought I’d report that there seems to be a huge spike in the flu – despite vaccinations – I can’t get over how many people seem to be coming down with severe symptoms.”

Some of those people had gotten the vaccine already — and apparently enough people have been wondering whether the vaccine really protects them that the DPH offers an explainer here: Can you still get the flu even if you have been vaccinated? 

Readers, what are you seeing?

Here’s WBUR’s latest on-air report: Continue reading