Pandemic influenza

The flu can be an unpredictable threat.

There are actually three types of influenza viruses (A, B and C) that cause the flu. These types are further classed into “subtypes”, like the A/H1N1 swine flu or A/H5N1 avian flu.

Each year, healthcare professionals predict which strains of the flu virus will be most common and mass-manufacture a vaccine targeting those strains.

This changes the makeup of the flu shot you get year to year. However, because it’s based on a prediction, it’s more effective some years than in others.

Vaccines generally work by giving the body a practice run for when a real infection occurs: this is a threat, destroy it if you see it. For many viruses and bacteria that don’t change a lot this works just fine, but the flu is sneaky and it often changes the way it looks.

Vaccines are also strain-specific (they teach your immune system to recognize the outside part of the virus), so when the flu changes the “old” vaccine is no longer effective against the “new” virus.

We’re working on a new type of vaccine that exploits parts of the influenza virus that don’t change as much as the rest of the virus as it evolves.

In collaboration with Trevor Douglas’ group from Indiana University, we’re developing and engineering a universal flu vaccine that would be protective against many (if not all) influenza strains.

It will teach the body to mount a protective and non-damaging immune response to the conserved parts of influenza viruses.

This research will take the guesswork out of influenza vaccines and could revolutionize the way we prevent flu infections.

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Q Fever

Q fever. Ever heard of it?

It doesn’t currently affect many people in developed countries, but infection rates have risen rapidly in the last decade. It’s highly infectious, can be deadly, and is found everywhere except Antarctica.

Q fever is an infection cause by a bacterium Coxiella burnetii, which humans get from animals. Domesticated herd animals like dairy cattle can carry the bacteria and entire herds can experience significant reproductive problems as a result.

Humans can get Q fever after contact with an infected animal’s bodily fluids, so veterinarians, farmers, and sheep shearers are among those most at risk of infection. People can also get Q fever from tick bites and ingestion of unpasteurized milk and dairy products.

Human infection takes 2 forms: acute and chronic. The acute form causes flu-like symptoms and can result in life-threatening pneumonia. Chronic Q fever is usually fatal if untreated, but mortality drops to just 10% with proper treatment.

Even though this disease was discovered more than 80 years ago, there is still not a good vaccine for it. Even worse: the best vaccine available can cause severe negative reactions if it’s administered to people who were exposed to this bacterium before (even if they didn’t actually get sick).

The NIH is sponsoring our efforts to develop a safer and more effective Q fever vaccine. Previous work pinpointed which type of cell response is best for defeating Q fever without damaging the body.

Now, we are using empty virus capsids (shells) to deliver Q fever vaccine candidates, and to manipulate the immune response for induction of only the protective mechanisms.