Dear Doctor: Apparently Japan just approved a new drug that can get rid of the flu virus in one day. When can we get this drug in the United States? And if we can't, can we order it online?

Dear Reader: The prospect of a one-dose drug that kills the influenza virus in 24 hours would be remarkable. As the most severe influenza outbreak in the U.S. in over a decade draws to a close, the news is riveting.

The drug, known as baloxavir marboxil, will be sold under the name Xofluza. In patient trials conducted in Japan, it killed influenza viruses in one day in most patients. That's significantly faster than Tamiflu, which until now has been the most effective influenza drug. With 3 to 5 million people worldwide affected each year by influenza epidemics that result in between 250,000 and 500,000 deaths, it's no surprise that Japanese officials put Xofluza on the fast track for approval.

According to the drug manufacturer, the new therapy is effective against influenza A and B viruses, and also showed promise against the H5N1 and H7N9 strains. Because viral shedding was shown to be controlled within two days, researchers are optimistic that the drug will also play a role in reducing transmission of the flu.

Viruses are basically microscopic (and sub-microscopic) protein-covered packets of genetic material whose core function is to copy themselves. They can only do this within the living cells of a host. Whether it's a bacterium, fungus, plant or animal, the virus gains control of the host cell's replication process and forces it to churn out copies of the viral genome.

The reason this new Japanese antiviral works so quickly is that it interferes with the ability of the influenza virus to copy itself. Specifically, the drug blocks an enzyme the virus needs to crack open and hijack the host cell's replication mechanisms. By killing the influenza virus within 24 hours, it is now the fastest-acting flu drug available.

Flu sufferers who take the new drug will still experience their fair share of flu symptoms. But results from patient studies suggest they will be milder and of shorter duration. Those who received the drug in patient trials had 24 hours of fever, while fever in those who received a placebo lasted nearly twice as long. Patients taking Xofluza returned to pre-influenza health status a full 40 hours faster than did those who received the placebo. And unlike Tamiflu, which is a five-day regimen of two pills per day, Xofluza is a single-dose, one pill regimen.

According to news reports, Xofluza is expected to be available in Japan sometime this spring, when the national insurer sets a price. The company plans to file for approval in the U.S., but Xofluza is not expected to be available until 2019.

As for whether you can buy the drug online before it becomes available here, the short answer is no. According to the Food and Drug Administration, it is illegal to buy drugs from other countries that have not been approved by the FDA for use and sale in the U.S.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Our doctor is retiring, and my wife and I have been told we need to select a new physician within two months. But we read the bios of available doctors in our area who are accepted by our insurance, and their degrees are not from first-class facilities. How can we make a good selection and be assured of quality care?

Dear Reader: Finding a primary doctor is not an easy task. You and your wife probably had a very long and good relationship with your physician. Such a relationship is not simply about treating a disease, taking care of vaccinations or providing preventive care. It's a human relationship -- one with ups and downs, but also mutual trust and a sense of comfort. So trying to replace that relationship is understandably daunting.

But let's ask: What makes a good primary doctor? It's not simply the source of the medical degree or the institution with which a doctor is associated. Those might be factors, but they might not speak to a doctor's overall quality.

If the doctor is affiliated with an institution, consider standard markers of quality about the institution itself, such as the percentage of patients getting vaccinations, colon cancer screenings, Pap smears and mammograms. Some states make this publicly available; California's Office of the Patient Advocate website is one example. Other, non-governmental websites provide patients' ratings of a doctor's care. Although multiple poor reviews could reflect poor quality of care, positive reviews don't necessarily reflect uniformly good care. Some offices encourage patients to provide good reviews, and some offices actively manage sites -- both of which can skew the results.

Then there's word of mouth. Try asking your friends, family or the people you work with for a recommendation. They may be able to give you an idea not only of a doctor's ability to diagnose and treat illnesses but also the doctor's personality. For many people, that's an important aspect of the doctor-patient relationship. Primary care doctors can be great diagnosticians, but can have personality traits that create barriers to good communication. If someone you trust attests to a doctor's ability to both communicate and to treat, this can be a powerful endorsement of his or her quality.

Another difficulty, of course, is the relative shortage of primary care physicians. After the cost of schooling and the physical and mental toils of residency, many physicians choose more lucrative specialties instead of primary care, which generally nets less income. In addition, some primary care physicians have concierge practices, meaning they accept a limited number of patients but at a higher cost to the patient.

Sometimes simply making an appointment with a new primary care doctor -- and assessing how his or her office is run -- is the only way to know whether a particular doctor will be a good fit. This may require some patience on your part. There may be some aspects of the office that you like and others that you don't, so expect an adjustment period.

But over time, you can again develop a good rapport with a doctor and have another trusted relationship for many years.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Coconut oil has gotten to be really popular, but now there's a study that says it's just as bad for you as beef fat and butter. How is that possible? It has no animal fat whatsoever.

Dear Reader: Coconut oil is definitely having a moment. It has gone from being a specialty item in the health food store to sitting side-by-side with the rest of the cooking oils in major grocery stores. And you're correct -- coconut oil is definitely not an animal product. However, that doesn't prevent it from being a saturated fat.

Coconut oil turns out to have a significantly higher percentage of saturated fat than does butter, beef fat or lard. Coconut oil is between 80 and 90 percent saturated fat. Butter is about 65 percent saturated fat, while lard and beef fat each come in at 40 percent saturated fat. The reason this is an issue is because saturated fat in the diet is associated with a rise in blood levels of low-density lipoprotein, or LDL cholesterol, the so-called "bad" cholesterol. Blood levels of LDL are tied to heart attack risk and cardiovascular disease.

But coconut oil has a few surprises as well. At the same time that it acts like a traditional saturated fat by raising LDL levels, it also has a beneficial effect on blood levels of high-density lipoprotein, or HDL, the so-called "good" cholesterol. While LDL is associated with the buildup of fatty deposits, known as plaque, in the arteries, HDL is believed to help clear that plaque away. It may be this beneficial effect on HDL that helped coconut oil earn a reputation as a healthful fat.

That brings us to the new study you referenced, which is actually an advisory from the American Heart Association. With cardiovascular disease causing more than 17 million deaths per year, the AHA used the advisory to reiterate the health benefits of choosing unsaturated fats over those that are saturated. In the report, the AHA cites coconut and palm oils as saturated fats to avoid, along with the usual suspects -- butter, lard and beef fat. That's why the news stories had those "coconut oil will kill you" headlines.

We believe the subject deserves a bit more nuance. First, it's important to remember that although fats are notorious for high calorie counts and an association with weight gain and heart disease, they're also essential nutrients. They're needed for metabolic functions like helping with the absorption of fat-soluble vitamins and micronutrients, and are required for the synthesis of the steroid hormones testosterone, estrogen and progesterone. The message is not that fats should be cut from the diet, but that they should be chosen wisely. We're also very interested in the continuing research that suggests inflammation plays as much of a role in cardiovascular disease as do cholesterol counts.

But back to coconut oil. In our opinion, it's not a miracle food and it's not a poison. It's a saturated fat with nice flavor and some very interesting nutritional properties. Just like butter or lard, coconut oil can be safely used in moderation.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)